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Data Acknowledgement if single node is used #1

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brodnev opened this issue Jun 21, 2018 · 1 comment
Closed

Data Acknowledgement if single node is used #1

brodnev opened this issue Jun 21, 2018 · 1 comment

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@brodnev
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brodnev commented Jun 21, 2018

The MPTCP uses Data Acknowledgement in order to retransmit data if one of the nodes fails permanently. Whatever, if there is only one (single) node between mptcp capable sender and mptcp capable receiver, does the Data Acknowledgement is still operating?

@mjmartineau
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@brodnev, for protocol questions like this I recommend either the multipath-tcp.org mailing list (https://listes-2.sipr.ucl.ac.be/sympa/info/mptcp-dev) for questions about the current Linux MPTCP implementation, or the Linux MPTCP upstreaming list at https://lists.01.org/mailman/listinfo/mptcp regarding the work-in-progress implementation in this github repo.

mjmartineau pushed a commit that referenced this issue Aug 10, 2018
Running the following:

 # cd /sys/kernel/debug/tracing
 # echo 500000 > buffer_size_kb
[ Or some other number that takes up most of memory ]
 # echo snapshot > events/sched/sched_switch/trigger

Triggers the following bug:

 ------------[ cut here ]------------
 kernel BUG at mm/slub.c:296!
 invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC PTI
 CPU: 6 PID: 6878 Comm: bash Not tainted 4.18.0-rc6-test+ #1066
 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03 07/14/2016
 RIP: 0010:kfree+0x16c/0x180
 Code: 05 41 0f b6 72 51 5b 5d 41 5c 4c 89 d7 e9 ac b3 f8 ff 48 89 d9 48 89 da 41 b8 01 00 00 00 5b 5d 41 5c 4c 89 d6 e9 f4 f3 ff ff <0f> 0b 0f 0b 48 8b 3d d9 d8 f9 00 e9 c1 fe ff ff 0f 1f 40 00 0f 1f
 RSP: 0018:ffffb654436d3d88 EFLAGS: 00010246
 RAX: ffff91a9d50f3d80 RBX: ffff91a9d50f3d80 RCX: ffff91a9d50f3d80
 RDX: 00000000000006a4 RSI: ffff91a9de5a60e0 RDI: ffff91a9d9803500
 RBP: ffffffff8d267c80 R08: 00000000000260e0 R09: ffffffff8c1a56be
 R10: fffff0d404543cc0 R11: 0000000000000389 R12: ffffffff8c1a56be
 R13: ffff91a9d9930e18 R14: ffff91a98c0c2890 R15: ffffffff8d267d00
 FS:  00007f363ea64700(0000) GS:ffff91a9de580000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 000055c1cacc8e10 CR3: 00000000d9b46003 CR4: 00000000001606e0
 Call Trace:
  event_trigger_callback+0xee/0x1d0
  event_trigger_write+0xfc/0x1a0
  __vfs_write+0x33/0x190
  ? handle_mm_fault+0x115/0x230
  ? _cond_resched+0x16/0x40
  vfs_write+0xb0/0x190
  ksys_write+0x52/0xc0
  do_syscall_64+0x5a/0x160
  entry_SYSCALL_64_after_hwframe+0x49/0xbe
 RIP: 0033:0x7f363e16ab50
 Code: 73 01 c3 48 8b 0d 38 83 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 79 db 2c 00 00 75 10 b8 01 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 1e e3 01 00 48 89 04 24
 RSP: 002b:00007fff9a4c6378 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
 RAX: ffffffffffffffda RBX: 0000000000000009 RCX: 00007f363e16ab50
 RDX: 0000000000000009 RSI: 000055c1cacc8e10 RDI: 0000000000000001
 RBP: 000055c1cacc8e10 R08: 00007f363e435740 R09: 00007f363ea64700
 R10: 0000000000000073 R11: 0000000000000246 R12: 0000000000000009
 R13: 0000000000000001 R14: 00007f363e4345e0 R15: 00007f363e4303c0
 Modules linked in: ip6table_filter ip6_tables snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic snd_hda_intel snd_hda_codec snd_hwdep snd_hda_core snd_seq snd_seq_device i915 snd_pcm snd_timer i2c_i801 snd soundcore i2c_algo_bit drm_kms_helper
86_pkg_temp_thermal video kvm_intel kvm irqbypass wmi e1000e
 ---[ end trace d301afa879ddfa25 ]---

The cause is because the register_snapshot_trigger() call failed to
allocate the snapshot buffer, and then called unregister_trigger()
which freed the data that was passed to it. Then on return to the
function that called register_snapshot_trigger(), as it sees it
failed to register, it frees the trigger_data again and causes
a double free.

By calling event_trigger_init() on the trigger_data (which only ups
the reference counter for it), and then event_trigger_free() afterward,
the trigger_data would not get freed by the registering trigger function
as it would only up and lower the ref count for it. If the register
trigger function fails, then the event_trigger_free() called after it
will free the trigger data normally.

Link: http://lkml.kernel.org/r/20180724191331.738eb819@gandalf.local.home

Cc: stable@vger.kerne.org
Fixes: 93e31ff ("tracing: Add 'snapshot' event trigger command")
Reported-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
mjmartineau pushed a commit that referenced this issue Aug 10, 2018
The number of eRPs that can be used by a single A-TCAM region is limited
to 16. When more eRPs are needed, an ordinary circuit TCAM (C-TCAM) can
be used to hold the extra eRPs.

Unlike the A-TCAM, only a single (last) lookup is performed in the
C-TCAM and not a lookup per-eRP. However, modeling the C-TCAM as extra
eRPs will allow us to easily introduce support for pruning in a
follow-up patch set and is also logically correct.

The following diagram depicts the relation between both TCAMs:
                                                                 C-TCAM
+-------------------+               +--------------------+    +-----------+
|                   |               |                    |    |           |
|  eRP #1 (A-TCAM)  +----> ... +----+  eRP #16 (A-TCAM)  +----+  eRP #17  |
|                   |               |                    |    |    ...    |
+-------------------+               +--------------------+    |  eRP #N   |
                                                              |           |
                                                              +-----------+
Lookup order is from left to right.

Extend the eRP core APIs with a C-TCAM parameter which indicates whether
the requested eRP is to be used with the C-TCAM or not.

Since the C-TCAM is only meant to absorb rules that can't fit in the
A-TCAM due to exceeded number of eRPs or key collision, an error is
returned when a C-TCAM eRP needs to be created when the eRP state
machine is in its initial state (i.e., 'no masks'). This should only
happen in the face of very unlikely errors when trying to push rules
into the A-TCAM.

In order not to perform unnecessary lookups, the eRP core will only
enable a C-TCAM lookup for a given region if it knows there are C-TCAM
eRPs present.

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
mjmartineau pushed a commit that referenced this issue Aug 10, 2018
Registration of a memory region(MR) through FRMR/fastreg(unlike FMR)
needs a connection/qp. With a proxy qp, this dependency on connection
will be removed, but that needs more infrastructure patches, which is a
work in progress.

As an intermediate fix, the get_mr returns EOPNOTSUPP when connection
details are not populated. The MR registration through sendmsg() will
continue to work even with fast registration, since connection in this
case is formed upfront.

This patch fixes the following crash:
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
Modules linked in:
CPU: 1 PID: 4244 Comm: syzkaller468044 Not tainted 4.16.0-rc6+ #361
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
RIP: 0010:rds_ib_get_mr+0x5c/0x230 net/rds/ib_rdma.c:544
RSP: 0018:ffff8801b059f890 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff8801b07e1300 RCX: ffffffff8562d96e
RDX: 000000000000000d RSI: 0000000000000001 RDI: 0000000000000068
RBP: ffff8801b059f8b8 R08: ffffed0036274244 R09: ffff8801b13a1200
R10: 0000000000000004 R11: ffffed0036274243 R12: ffff8801b13a1200
R13: 0000000000000001 R14: ffff8801ca09fa9c R15: 0000000000000000
FS:  00007f4d050af700(0000) GS:ffff8801db300000(0000)
knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4d050aee78 CR3: 00000001b0d9b006 CR4: 00000000001606e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __rds_rdma_map+0x710/0x1050 net/rds/rdma.c:271
 rds_get_mr_for_dest+0x1d4/0x2c0 net/rds/rdma.c:357
 rds_setsockopt+0x6cc/0x980 net/rds/af_rds.c:347
 SYSC_setsockopt net/socket.c:1849 [inline]
 SyS_setsockopt+0x189/0x360 net/socket.c:1828
 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x4456d9
RSP: 002b:00007f4d050aedb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 00000000006dac3c RCX: 00000000004456d9
RDX: 0000000000000007 RSI: 0000000000000114 RDI: 0000000000000004
RBP: 00000000006dac38 R08: 00000000000000a0 R09: 0000000000000000
R10: 0000000020000380 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fffbfb36d6f R14: 00007f4d050af9c0 R15: 0000000000000005
Code: fa 48 c1 ea 03 80 3c 02 00 0f 85 cc 01 00 00 4c 8b bb 80 04 00 00
48
b8 00 00 00 00 00 fc ff df 49 8d 7f 68 48 89 fa 48 c1 ea 03 <80> 3c 02
00 0f
85 9c 01 00 00 4d 8b 7f 68 48 b8 00 00 00 00 00
RIP: rds_ib_get_mr+0x5c/0x230 net/rds/ib_rdma.c:544 RSP:
ffff8801b059f890
---[ end trace 7e1cea13b85473b0 ]---

Reported-by: syzbot+b51c77ef956678a65834@syzkaller.appspotmail.com
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: Avinash Repaka <avinash.repaka@oracle.com>

Signed-off-by: David S. Miller <davem@davemloft.net>
mjmartineau pushed a commit that referenced this issue Aug 10, 2018
…ilure

While forking, if delayacct init fails due to memory shortage, it
continues expecting all delayacct users to check task->delays pointer
against NULL before dereferencing it, which all of them used to do.

Commit c96f547 ("delayacct: Account blkio completion on the correct
task"), while updating delayacct_blkio_end() to take the target task
instead of always using %current, made the function test NULL on
%current->delays and then continue to operated on @p->delays.  If
%current succeeded init while @p didn't, it leads to the following
crash.

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000004
 IP: __delayacct_blkio_end+0xc/0x40
 PGD 8000001fd07e1067 P4D 8000001fd07e1067 PUD 1fcffbb067 PMD 0
 Oops: 0000 [#1] SMP PTI
 CPU: 4 PID: 25774 Comm: QIOThread0 Not tainted 4.16.0-9_fbk1_rc2_1180_g6b593215b4d7 #9
 RIP: 0010:__delayacct_blkio_end+0xc/0x40
 Call Trace:
  try_to_wake_up+0x2c0/0x600
  autoremove_wake_function+0xe/0x30
  __wake_up_common+0x74/0x120
  wake_up_page_bit+0x9c/0xe0
  mpage_end_io+0x27/0x70
  blk_update_request+0x78/0x2c0
  scsi_end_request+0x2c/0x1e0
  scsi_io_completion+0x20b/0x5f0
  blk_mq_complete_request+0xa2/0x100
  ata_scsi_qc_complete+0x79/0x400
  ata_qc_complete_multiple+0x86/0xd0
  ahci_handle_port_interrupt+0xc9/0x5c0
  ahci_handle_port_intr+0x54/0xb0
  ahci_single_level_irq_intr+0x3b/0x60
  __handle_irq_event_percpu+0x43/0x190
  handle_irq_event_percpu+0x20/0x50
  handle_irq_event+0x2a/0x50
  handle_edge_irq+0x80/0x1c0
  handle_irq+0xaf/0x120
  do_IRQ+0x41/0xc0
  common_interrupt+0xf/0xf

Fix it by updating delayacct_blkio_end() check @p->delays instead.

Link: http://lkml.kernel.org/r/20180724175542.GP1934745@devbig577.frc2.facebook.com
Fixes: c96f547 ("delayacct: Account blkio completion on the correct task")
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Dave Jones <dsj@fb.com>
Debugged-by: Dave Jones <dsj@fb.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Josh Snyder <joshs@netflix.com>
Cc: <stable@vger.kernel.org>	[4.15+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mjmartineau pushed a commit that referenced this issue Aug 10, 2018
vma_is_anonymous() relies on ->vm_ops being NULL to detect anonymous
VMA.  This is unreliable as ->mmap may not set ->vm_ops.

False-positive vma_is_anonymous() may lead to crashes:

	next ffff8801ce5e7040 prev ffff8801d20eca50 mm ffff88019c1e13c0
	prot 27 anon_vma ffff88019680cdd8 vm_ops 0000000000000000
	pgoff 0 file ffff8801b2ec2d00 private_data 0000000000000000
	flags: 0xff(read|write|exec|shared|mayread|maywrite|mayexec|mayshare)
	------------[ cut here ]------------
	kernel BUG at mm/memory.c:1422!
	invalid opcode: 0000 [#1] SMP KASAN
	CPU: 0 PID: 18486 Comm: syz-executor3 Not tainted 4.18.0-rc3+ #136
	Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google
	01/01/2011
	RIP: 0010:zap_pmd_range mm/memory.c:1421 [inline]
	RIP: 0010:zap_pud_range mm/memory.c:1466 [inline]
	RIP: 0010:zap_p4d_range mm/memory.c:1487 [inline]
	RIP: 0010:unmap_page_range+0x1c18/0x2220 mm/memory.c:1508
	Call Trace:
	 unmap_single_vma+0x1a0/0x310 mm/memory.c:1553
	 zap_page_range_single+0x3cc/0x580 mm/memory.c:1644
	 unmap_mapping_range_vma mm/memory.c:2792 [inline]
	 unmap_mapping_range_tree mm/memory.c:2813 [inline]
	 unmap_mapping_pages+0x3a7/0x5b0 mm/memory.c:2845
	 unmap_mapping_range+0x48/0x60 mm/memory.c:2880
	 truncate_pagecache+0x54/0x90 mm/truncate.c:800
	 truncate_setsize+0x70/0xb0 mm/truncate.c:826
	 simple_setattr+0xe9/0x110 fs/libfs.c:409
	 notify_change+0xf13/0x10f0 fs/attr.c:335
	 do_truncate+0x1ac/0x2b0 fs/open.c:63
	 do_sys_ftruncate+0x492/0x560 fs/open.c:205
	 __do_sys_ftruncate fs/open.c:215 [inline]
	 __se_sys_ftruncate fs/open.c:213 [inline]
	 __x64_sys_ftruncate+0x59/0x80 fs/open.c:213
	 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
	 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Reproducer:

	#include <stdio.h>
	#include <stddef.h>
	#include <stdint.h>
	#include <stdlib.h>
	#include <string.h>
	#include <sys/types.h>
	#include <sys/stat.h>
	#include <sys/ioctl.h>
	#include <sys/mman.h>
	#include <unistd.h>
	#include <fcntl.h>

	#define KCOV_INIT_TRACE			_IOR('c', 1, unsigned long)
	#define KCOV_ENABLE			_IO('c', 100)
	#define KCOV_DISABLE			_IO('c', 101)
	#define COVER_SIZE			(1024<<10)

	#define KCOV_TRACE_PC  0
	#define KCOV_TRACE_CMP 1

	int main(int argc, char **argv)
	{
		int fd;
		unsigned long *cover;

		system("mount -t debugfs none /sys/kernel/debug");
		fd = open("/sys/kernel/debug/kcov", O_RDWR);
		ioctl(fd, KCOV_INIT_TRACE, COVER_SIZE);
		cover = mmap(NULL, COVER_SIZE * sizeof(unsigned long),
				PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
		munmap(cover, COVER_SIZE * sizeof(unsigned long));
		cover = mmap(NULL, COVER_SIZE * sizeof(unsigned long),
				PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
		memset(cover, 0, COVER_SIZE * sizeof(unsigned long));
		ftruncate(fd, 3UL << 20);
		return 0;
	}

This can be fixed by assigning anonymous VMAs own vm_ops and not relying
on it being NULL.

If ->mmap() failed to set ->vm_ops, mmap_region() will set it to
dummy_vm_ops.  This way we will have non-NULL ->vm_ops for all VMAs.

Link: http://lkml.kernel.org/r/20180724121139.62570-4-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: syzbot+3f84280d52be9b7083cc@syzkaller.appspotmail.com
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mjmartineau pushed a commit that referenced this issue Aug 10, 2018
Ido Schimmel says:

====================
mlxsw: Support DSCP prioritization and rewrite

Petr says:

On ingress, a network device such as a switch assigns to packets
priority based on various criteria. Common options include interpreting
PCP and DSCP fields according to user configuration. When a packet
egresses the switch, a reverse process may rewrite PCP and/or DSCP
headers according to packet priority.

So far, mlxsw has supported prioritization based on PCP (802.1p priority
tag). This patch set introduces support for prioritization based on
DSCP, and DSCP rewrite.

To configure the DSCP-to-priority maps, the user is expected to invoke
ieee_setapp and ieee_delapp DCBNL ops, e.g. by using lldptool:

To decide whether or not to pay attention to DSCP values, the Spectrum
switch recognize a per-port configuration of trust level. Until the
first APP rule is added for a given port, this port's trust level stays
at PCP, meaning that PCP is used for packet prioritization. With the
first DSCP APP rule, the port is configured to trust DSCP instead, and
it stays there until all DSCP APP rules are removed again.

Besides the DSCP (value 5) selector, another selector that plays into
packet prioritization is Ethernet type (value 1) with PID of 0. Such APP
entries denote default priority[1]:

With this patch set, mlxsw uses these values to configure priority for
DSCP values not explicitly specified in DSCP APP map. In the future we
expect to also use this to configure default port priority for untagged
packets.

Access to DSCP-to-priority map, priority-to-DSCP map, and default
priority for a port is exposed through three new DCB helpers. Like the
already-existing dcb_ieee_getapp_mask() helper, these helpers operate in
terms of bitmaps, to support the arbitrary M:N mapping that the APP
rules allow. Such interface presents all the relevant information from
the APP database without necessitating exposition of iterators, locking
or other complex primitives. It is up to the driver to then digest the
mapping in a way that the device supports. In this patch set, mlxsw
resolves conflicts by favoring higher-numbered DSCP values and
priorities.

In this patchset:

- Patch #1 fixes a bug in DCB APP database management.
- Patch #2 adds the getters described above.
- Patches #3-#6 add Spectrum configuration registers.
- Patch #7 adds the mlxsw logic that configures the device according to
  APP rules.
- Patch #8 adds a self-test. The test is added to the subdirectory
  drivers/net/mlxsw. Even though it's not particularly specific to
  mlxsw, it's not suitable for running on soft devices (which don't
  support the ieee_getapp et.al.), and thus isn't a good fit for the
  general net/forwarding directory.

[1] 802.1Q-2014, Table D-9
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
mjmartineau pushed a commit that referenced this issue Aug 10, 2018
bpf_parse_prog() is protected by rcu_read_lock().
so that GFP_KERNEL is not allowed in the bpf_parse_prog().

[51015.579396] =============================
[51015.579418] WARNING: suspicious RCU usage
[51015.579444] 4.18.0-rc6+ #208 Not tainted
[51015.579464] -----------------------------
[51015.579488] ./include/linux/rcupdate.h:303 Illegal context switch in RCU read-side critical section!
[51015.579510] other info that might help us debug this:
[51015.579532] rcu_scheduler_active = 2, debug_locks = 1
[51015.579556] 2 locks held by ip/1861:
[51015.579577]  #0: 00000000a8c12fd1 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x2e0/0x910
[51015.579711]  #1: 00000000bf815f8e (rcu_read_lock){....}, at: lwtunnel_build_state+0x96/0x390
[51015.579842] stack backtrace:
[51015.579869] CPU: 0 PID: 1861 Comm: ip Not tainted 4.18.0-rc6+ #208
[51015.579891] Hardware name: To be filled by O.E.M. To be filled by O.E.M./Aptio CRB, BIOS 5.6.5 07/08/2015
[51015.579911] Call Trace:
[51015.579950]  dump_stack+0x74/0xbb
[51015.580000]  ___might_sleep+0x16b/0x3a0
[51015.580047]  __kmalloc_track_caller+0x220/0x380
[51015.580077]  kmemdup+0x1c/0x40
[51015.580077]  bpf_parse_prog+0x10e/0x230
[51015.580164]  ? kasan_kmalloc+0xa0/0xd0
[51015.580164]  ? bpf_destroy_state+0x30/0x30
[51015.580164]  ? bpf_build_state+0xe2/0x3e0
[51015.580164]  bpf_build_state+0x1bb/0x3e0
[51015.580164]  ? bpf_parse_prog+0x230/0x230
[51015.580164]  ? lock_is_held_type+0x123/0x1a0
[51015.580164]  lwtunnel_build_state+0x1aa/0x390
[51015.580164]  fib_create_info+0x1579/0x33d0
[51015.580164]  ? sched_clock_local+0xe2/0x150
[51015.580164]  ? fib_info_update_nh_saddr+0x1f0/0x1f0
[51015.580164]  ? sched_clock_local+0xe2/0x150
[51015.580164]  fib_table_insert+0x201/0x1990
[51015.580164]  ? lock_downgrade+0x610/0x610
[51015.580164]  ? fib_table_lookup+0x1920/0x1920
[51015.580164]  ? lwtunnel_valid_encap_type.part.6+0xcb/0x3a0
[51015.580164]  ? rtm_to_fib_config+0x637/0xbd0
[51015.580164]  inet_rtm_newroute+0xed/0x1b0
[51015.580164]  ? rtm_to_fib_config+0xbd0/0xbd0
[51015.580164]  rtnetlink_rcv_msg+0x331/0x910
[ ... ]

Fixes: 3a0af8f ("bpf: BPF for lightweight tunnel infrastructure")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
mjmartineau pushed a commit that referenced this issue Aug 10, 2018
Kernel panic when with high memory pressure, calltrace looks like,

PID: 21439 TASK: ffff881be3afedd0 CPU: 16 COMMAND: "java"
 #0 [ffff881ec7ed7630] machine_kexec at ffffffff81059beb
 #1 [ffff881ec7ed7690] __crash_kexec at ffffffff81105942
 #2 [ffff881ec7ed7760] crash_kexec at ffffffff81105a30
 #3 [ffff881ec7ed7778] oops_end at ffffffff816902c8
 #4 [ffff881ec7ed77a0] no_context at ffffffff8167ff46
 #5 [ffff881ec7ed77f0] __bad_area_nosemaphore at ffffffff8167ffdc
 #6 [ffff881ec7ed7838] __node_set at ffffffff81680300
 #7 [ffff881ec7ed7860] __do_page_fault at ffffffff8169320f
 #8 [ffff881ec7ed78c0] do_page_fault at ffffffff816932b5
 #9 [ffff881ec7ed78f0] page_fault at ffffffff8168f4c8
    [exception RIP: _raw_spin_lock_irqsave+47]
    RIP: ffffffff8168edef RSP: ffff881ec7ed79a8 RFLAGS: 00010046
    RAX: 0000000000000246 RBX: ffffea0019740d00 RCX: ffff881ec7ed7fd8
    RDX: 0000000000020000 RSI: 0000000000000016 RDI: 0000000000000008
    RBP: ffff881ec7ed79a8 R8: 0000000000000246 R9: 000000000001a098
    R10: ffff88107ffda000 R11: 0000000000000000 R12: 0000000000000000
    R13: 0000000000000008 R14: ffff881ec7ed7a80 R15: ffff881be3afedd0
    ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018

It happens in the pagefault and results in double pagefault
during compacting pages when memory allocation fails.

Analysed the vmcore, the page leads to second pagefault is corrupted
with _mapcount=-256, but private=0.

It's caused by the race between migration and ballooning, and lock
missing in virtballoon_migratepage() of virtio_balloon driver.
This patch fix the bug.

Fixes: e225042 ("virtio_balloon: introduce migration primitives to balloon pages")
Cc: stable@vger.kernel.org
Signed-off-by: Jiang Biao <jiang.biao2@zte.com.cn>
Signed-off-by: Huang Chong <huang.chong@zte.com.cn>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
mjmartineau pushed a commit that referenced this issue Aug 10, 2018
Petr Machata says:

====================
A test for mirror-to-gretap with team in UL packet path

This patchset adds a test for "tc action mirred mirror" where the
mirrored-to device is a gretap, and underlay path contains a team
device.

In patch #1 require_command() is added, which should henceforth be used
to declare dependence on a certain tool.

In patch #2, two new functions, team_create() and team_destroy(), are
added to lib.sh.

The newly-added test uses arping, which isn't necessarily available.
Therefore patch #3 introduces $ARPING, and a preexisting test is fixed
to require_command $ARPING.

In patches #4 and #5, two new tests are added. In both cases, a team
device is on egress path of a mirrored packet in a mirror-to-gretap
scenario. In the first one, the team device is in loadbalance mode, in
the second one it's in lacp mode. (The difference in modes necessitates
a different testing strategy, hence two test cases instead of just
parameterizing one.)
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
mjmartineau pushed a commit that referenced this issue Aug 10, 2018
syzbot found that the following sequence produces a LOCKDEP splat [1]

ip link add bond10 type bond
ip link add bond11 type bond
ip link set bond11 master bond10

To fix this, we can use the already provided nest_level.

This patch also provides correct nesting for dev->addr_list_lock

[1]
WARNING: possible recursive locking detected
4.18.0-rc6+ #167 Not tainted
--------------------------------------------
syz-executor751/4439 is trying to acquire lock:
(____ptrval____) (&(&bond->stats_lock)->rlock){+.+.}, at: spin_lock include/linux/spinlock.h:310 [inline]
(____ptrval____) (&(&bond->stats_lock)->rlock){+.+.}, at: bond_get_stats+0xb4/0x560 drivers/net/bonding/bond_main.c:3426

but task is already holding lock:
(____ptrval____) (&(&bond->stats_lock)->rlock){+.+.}, at: spin_lock include/linux/spinlock.h:310 [inline]
(____ptrval____) (&(&bond->stats_lock)->rlock){+.+.}, at: bond_get_stats+0xb4/0x560 drivers/net/bonding/bond_main.c:3426

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&(&bond->stats_lock)->rlock);
  lock(&(&bond->stats_lock)->rlock);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

3 locks held by syz-executor751/4439:
 #0: (____ptrval____) (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:77
 #1: (____ptrval____) (&(&bond->stats_lock)->rlock){+.+.}, at: spin_lock include/linux/spinlock.h:310 [inline]
 #1: (____ptrval____) (&(&bond->stats_lock)->rlock){+.+.}, at: bond_get_stats+0xb4/0x560 drivers/net/bonding/bond_main.c:3426
 #2: (____ptrval____) (rcu_read_lock){....}, at: bond_get_stats+0x0/0x560 include/linux/compiler.h:215

stack backtrace:
CPU: 0 PID: 4439 Comm: syz-executor751 Not tainted 4.18.0-rc6+ #167
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c9/0x2b4 lib/dump_stack.c:113
 print_deadlock_bug kernel/locking/lockdep.c:1765 [inline]
 check_deadlock kernel/locking/lockdep.c:1809 [inline]
 validate_chain kernel/locking/lockdep.c:2405 [inline]
 __lock_acquire.cold.64+0x1fb/0x486 kernel/locking/lockdep.c:3435
 lock_acquire+0x1e4/0x540 kernel/locking/lockdep.c:3924
 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:144
 spin_lock include/linux/spinlock.h:310 [inline]
 bond_get_stats+0xb4/0x560 drivers/net/bonding/bond_main.c:3426
 dev_get_stats+0x10f/0x470 net/core/dev.c:8316
 bond_get_stats+0x232/0x560 drivers/net/bonding/bond_main.c:3432
 dev_get_stats+0x10f/0x470 net/core/dev.c:8316
 rtnl_fill_stats+0x4d/0xac0 net/core/rtnetlink.c:1169
 rtnl_fill_ifinfo+0x1aa6/0x3fb0 net/core/rtnetlink.c:1611
 rtmsg_ifinfo_build_skb+0xc8/0x190 net/core/rtnetlink.c:3268
 rtmsg_ifinfo_event.part.30+0x45/0xe0 net/core/rtnetlink.c:3300
 rtmsg_ifinfo_event net/core/rtnetlink.c:3297 [inline]
 rtnetlink_event+0x144/0x170 net/core/rtnetlink.c:4716
 notifier_call_chain+0x180/0x390 kernel/notifier.c:93
 __raw_notifier_call_chain kernel/notifier.c:394 [inline]
 raw_notifier_call_chain+0x2d/0x40 kernel/notifier.c:401
 call_netdevice_notifiers_info+0x3f/0x90 net/core/dev.c:1735
 call_netdevice_notifiers net/core/dev.c:1753 [inline]
 netdev_features_change net/core/dev.c:1321 [inline]
 netdev_change_features+0xb3/0x110 net/core/dev.c:7759
 bond_compute_features.isra.47+0x585/0xa50 drivers/net/bonding/bond_main.c:1120
 bond_enslave+0x1b25/0x5da0 drivers/net/bonding/bond_main.c:1755
 bond_do_ioctl+0x7cb/0xae0 drivers/net/bonding/bond_main.c:3528
 dev_ifsioc+0x43c/0xb30 net/core/dev_ioctl.c:327
 dev_ioctl+0x1b5/0xcc0 net/core/dev_ioctl.c:493
 sock_do_ioctl+0x1d3/0x3e0 net/socket.c:992
 sock_ioctl+0x30d/0x680 net/socket.c:1093
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x1de/0x1720 fs/ioctl.c:684
 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:701
 __do_sys_ioctl fs/ioctl.c:708 [inline]
 __se_sys_ioctl fs/ioctl.c:706 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:706
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x440859
Code: e8 2c af 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 3b 10 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffc51a92878 EFLAGS: 00000213 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000440859
RDX: 0000000020000040 RSI: 0000000000008990 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00000000004002c8 R09: 00000000004002c8
R10: 00000000022d5880 R11: 0000000000000213 R12: 0000000000007390
R13: 0000000000401db0 R14: 0000000000000000 R15: 0000000000000000

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Jay Vosburgh <j.vosburgh@gmail.com>
Cc: Veaceslav Falico <vfalico@gmail.com>
Cc: Andy Gospodarek <andy@greyhouse.net>

Signed-off-by: David S. Miller <davem@davemloft.net>
mjmartineau pushed a commit that referenced this issue Aug 10, 2018
Petr Machata says:

====================
ipv4: Control SKB reprioritization after forwarding

After IPv4 packets are forwarded, the priority of the corresponding SKB
is updated according to the TOS field of IPv4 header. This overrides any
prioritization done earlier by e.g. an skbedit action or ingress-qos-map
defined at a vlan device.

Such overriding may not always be desirable. Even if the packet ends up
being routed, which implies this is an L3 network node, an administrator
may wish to preserve whatever prioritization was done earlier on in the
pipeline.

Therefore this patch set introduces a sysctl that controls this
behavior, net.ipv4.ip_forward_update_priority. It's value is 1 by
default to preserve the current behavior.

All of the above is implemented in patch #1.

Value changes prompt a new NETEVENT_IPV4_FWD_UPDATE_PRIORITY_UPDATE
notification, so that the drivers can hook up whatever logic may depend
on this value. That is implemented in patch #2.

In patches #3 and #4, mlxsw is adapted to recognize the sysctl. On
initialization, the RGCR register that handles router configuration is
set in accordance with the sysctl. The new notification is listened to
and RGCR is reconfigured as necessary.

In patches #5 to #7, a selftest is added to verify that mlxsw reflects
the sysctl value as necessary. The test is expressed in terms of the
recently-introduced ieee_setapp support, and works by observing how DSCP
value gets rewritten depending on packet priority. For this reason, the
test is added to the subdirectory drivers/net/mlxsw. Even though it's
not particularly specific to mlxsw, it's not suitable for running on
soft devices (which don't support the ieee_setapp et.al.).

Changes from v1 to v2:

- In patch #1, init sysctl_ip_fwd_update_priority to 1 instead of true.

Changes from RFC to v1:

- Fix wrong sysctl name in ip-sysctl.txt
- Add notifications
- Add mlxsw support
- Add self test
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
mjmartineau pushed a commit that referenced this issue Aug 10, 2018
Amit Pundir and Youling in parallel reported crashes with recent
mainline kernels running Android:

  F DEBUG   : *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***
  F DEBUG   : Build fingerprint: 'Android/db410c32_only/db410c32_only:Q/OC-MR1/102:userdebug/test-key
  F DEBUG   : Revision: '0'
  F DEBUG   : ABI: 'arm'
  F DEBUG   : pid: 2261, tid: 2261, name: zygote  >>> zygote <<<
  F DEBUG   : signal 7 (SIGBUS), code 2 (BUS_ADRERR), fault addr 0xec00008
  ... <snip> ...
  F DEBUG   : backtrace:
  F DEBUG   :     #00 pc 00001c04  /system/lib/libc.so (memset+48)
  F DEBUG   :     #1 pc 0010c513  /system/lib/libart.so (create_mspace_with_base+82)
  F DEBUG   :     #2 pc 0015c601  /system/lib/libart.so (art::gc::space::DlMallocSpace::CreateMspace(void*, unsigned int, unsigned int)+40)
  F DEBUG   :     #3 pc 0015c3ed  /system/lib/libart.so (art::gc::space::DlMallocSpace::CreateFromMemMap(art::MemMap*, std::__1::basic_string<char, std::__ 1::char_traits<char>, std::__1::allocator<char>> const&, unsigned int, unsigned int, unsigned int, unsigned int, bool)+36)
  ...

This was bisected back to commit bfd40ea ("mm: fix
vma_is_anonymous() false-positives").

create_mspace_with_base() in the trace above, utilizes ashmem, and with
ashmem, for shared mappings we use shmem_zero_setup(), which sets the
vma->vm_ops to &shmem_vm_ops.  But for private ashmem mappings nothing
sets the vma->vm_ops.

Looking at the problematic patch, it seems to add a requirement that one
call vma_set_anonymous() on a vma, otherwise the dummy_vm_ops will be
used.  Using the dummy_vm_ops seem to triggger SIGBUS when traversing
unmapped pages.

Thus, this patch adds a call to vma_set_anonymous() for ashmem private
mappings and seems to avoid the reported problem.

Fixes: bfd40ea ("mm: fix vma_is_anonymous() false-positives")
Cc: Kirill Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Colin Cross <ccross@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Reported-by: Amit Pundir <amit.pundir@linaro.org>
Reported-by: Youling 257 <youling257@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mjmartineau pushed a commit that referenced this issue Aug 10, 2018
Add the following verifier tests to cover the cgroup storage
functionality:
1) valid access to the cgroup storage
2) invalid access: use regular hashmap instead of cgroup storage map
3) invalid access: use invalid map fd
4) invalid access: try access memory after the cgroup storage
5) invalid access: try access memory before the cgroup storage
6) invalid access: call get_local_storage() with non-zero flags

For tests 2)-6) check returned error strings.

Expected output:
  $ ./test_verifier
  #0/u add+sub+mul OK
  #0/p add+sub+mul OK
  #1/u DIV32 by 0, zero check 1 OK
  ...
  #280/p valid cgroup storage access OK
  #281/p invalid cgroup storage access 1 OK
  #282/p invalid cgroup storage access 2 OK
  #283/p invalid per-cgroup storage access 3 OK
  #284/p invalid cgroup storage access 4 OK
  #285/p invalid cgroup storage access 5 OK
  ...
  #649/p pass modified ctx pointer to helper, 2 OK
  #650/p pass modified ctx pointer to helper, 3 OK
  Summary: 901 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: Roman Gushchin <guro@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
mjmartineau pushed a commit that referenced this issue Aug 10, 2018
Guillaume Nault says:

====================
l2tp: sanitise MTU handling on sessions

Most of the code handling sessions' MTU has no effect. The ->mtu field
in struct l2tp_session might be used at session creation time, but
neither PPP nor Ethernet pseudo-wires take updates into account.

L2TP sessions don't have a concept of MTU, which is the reason why
->mtu is mostly ignored. MTU should remain a network device thing.
Therefore this patch set does not try to propagate/update ->mtu to/from
the device. That would complicate the code unnecessarily. Instead this
field and the associated ioctl commands and netlink attributes are
removed.

Patch #1 defines l2tp_tunnel_dst_mtu() in order to simplify the
following patches. Then patches #2 and #3 remove MTU handling from PPP
and Ethernet pseudo-wires respectively.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
mjmartineau pushed a commit that referenced this issue Aug 10, 2018
Ido Schimmel says:

====================
mlxsw: Enable MC-aware mode for mlxsw ports

Petr says:

Due to an issue in Spectrum chips, when unicast traffic shares the same
queue as BUM traffic, and there is a congestion, the BUM traffic is
admitted to the queue anyway, thus pushing out all UC traffic. In order
to give unicast traffic precedence over BUM traffic, configure
multicast-aware mode on all ports.

Under multicast-aware regime, when assigning traffic class to a packet,
the switch doesn't merely take the value prescribed by the QTCT
register. For BUM traffic, it instead assigns that value plus 8. That
limits the number of available TCs, but since mlxsw currently only uses
the lower eight anyway, it is no real loss.

The two TCs (UC and MC one) are then mapped to the same subgroup and
strictly prioritized so that UC traffic is preferred in case of
congestion.

In patch #1, introduce a new register, QTCTM, which enables the
multicast-aware mode.

In patch #2, fix a typo in related code.

In patch #3, set up TCs and QTCTM to enable multicast-aware mode.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
mjmartineau pushed a commit that referenced this issue Aug 10, 2018
The shift of 'cwnd' with '(now - hc->tx_lsndtime) / hc->tx_rto' value
can lead to undefined behavior [1].

In order to fix this use a gradual shift of the window with a 'while'
loop, similar to what tcp_cwnd_restart() is doing.

When comparing delta and RTO there is a minor difference between TCP
and DCCP, the last one also invokes dccp_cwnd_restart() and reduces
'cwnd' if delta equals RTO. That case is preserved in this change.

[1]:
[40850.963623] UBSAN: Undefined behaviour in net/dccp/ccids/ccid2.c:237:7
[40851.043858] shift exponent 67 is too large for 32-bit type 'unsigned int'
[40851.127163] CPU: 3 PID: 15940 Comm: netstress Tainted: G        W   E     4.18.0-rc7.x86_64 #1
...
[40851.377176] Call Trace:
[40851.408503]  dump_stack+0xf1/0x17b
[40851.451331]  ? show_regs_print_info+0x5/0x5
[40851.503555]  ubsan_epilogue+0x9/0x7c
[40851.548363]  __ubsan_handle_shift_out_of_bounds+0x25b/0x2b4
[40851.617109]  ? __ubsan_handle_load_invalid_value+0x18f/0x18f
[40851.686796]  ? xfrm4_output_finish+0x80/0x80
[40851.739827]  ? lock_downgrade+0x6d0/0x6d0
[40851.789744]  ? xfrm4_prepare_output+0x160/0x160
[40851.845912]  ? ip_queue_xmit+0x810/0x1db0
[40851.895845]  ? ccid2_hc_tx_packet_sent+0xd36/0x10a0 [dccp]
[40851.963530]  ccid2_hc_tx_packet_sent+0xd36/0x10a0 [dccp]
[40852.029063]  dccp_xmit_packet+0x1d3/0x720 [dccp]
[40852.086254]  dccp_write_xmit+0x116/0x1d0 [dccp]
[40852.142412]  dccp_sendmsg+0x428/0xb20 [dccp]
[40852.195454]  ? inet_dccp_listen+0x200/0x200 [dccp]
[40852.254833]  ? sched_clock+0x5/0x10
[40852.298508]  ? sched_clock+0x5/0x10
[40852.342194]  ? inet_create+0xdf0/0xdf0
[40852.388988]  sock_sendmsg+0xd9/0x160
...

Fixes: 113ced1 ("dccp ccid-2: Perform congestion-window validation")
Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
mjmartineau pushed a commit that referenced this issue Aug 10, 2018
The definition of static_key_slow_inc() has cpus_read_lock in place. In the
virtio_net driver, XPS queues are initialized after setting the queue:cpu
affinity in virtnet_set_affinity() which is already protected within
cpus_read_lock. Lockdep prints a warning when we are trying to acquire
cpus_read_lock when it is already held.

This patch adds an ability to call __netif_set_xps_queue under
cpus_read_lock().
Acked-by: Jason Wang <jasowang@redhat.com>

============================================
WARNING: possible recursive locking detected
4.18.0-rc3-next-20180703+ #1 Not tainted
--------------------------------------------
swapper/0/1 is trying to acquire lock:
00000000cf973d46 (cpu_hotplug_lock.rw_sem){++++}, at: static_key_slow_inc+0xe/0x20

but task is already holding lock:
00000000cf973d46 (cpu_hotplug_lock.rw_sem){++++}, at: init_vqs+0x513/0x5a0

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(cpu_hotplug_lock.rw_sem);
  lock(cpu_hotplug_lock.rw_sem);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

3 locks held by swapper/0/1:
 #0: 00000000244bc7da (&dev->mutex){....}, at: __driver_attach+0x5a/0x110
 #1: 00000000cf973d46 (cpu_hotplug_lock.rw_sem){++++}, at: init_vqs+0x513/0x5a0
 #2: 000000005cd8463f (xps_map_mutex){+.+.}, at: __netif_set_xps_queue+0x8d/0xc60

v2: move cpus_read_lock() out of __netif_set_xps_queue()

Cc: "Nambiar, Amritha" <amritha.nambiar@intel.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Fixes: 8af2c06 ("net-sysfs: Add interface for Rx queue(s) map per Tx queue")

Signed-off-by: Andrei Vagin <avagin@gmail.com>

Signed-off-by: David S. Miller <davem@davemloft.net>
mjmartineau pushed a commit that referenced this issue Sep 12, 2018
…_read

Subflows can get removed from under our feet, thus we might be iterating
on garbage here.

That can panic like:

[52899.160112] BUG: unable to handle kernel NULL pointer dereference at           (null)
[52899.160157] IP: tcp_splice_read+0x225/0x330
[52899.160166] PGD 8000000164ff8067 P4D 8000000164ff8067 PUD 163d67067 PMD 0
[52899.160189] Oops: 0000 [#1] SMP PTI
[52899.160198] Modules linked in: binfmt_misc xt_REDIRECT nf_nat_redirect xt_statistic xt_mark ipt_MASQUERADE nf_nat_masquerade_ipv4 xt_connmark xt_nat xt_comment xt_geoip(O) xt_conntrack iptable_mangle iptable_nat nf_nat_ipv4 nf_nat iptable_filter sch_fq_codel nf_conntrack_tftp nf_conntrack_ipv4 nf_defrag_ipv4 nf_conntrack_proto_gre nf_conntrack_irc nf_conntrack_ftp nf_conntrack pcspkr tun it87 hwmon_vid vfat fat x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm irqbypass crct10dif_pclmul crc32_pclmul ghash_clmulni_intel pcbc aesni_intel crypto_simd glue_helper cryptd iTCO_wdt i2c_designware_platform iTCO_vendor_support i2c_designware_core intel_cstate intel_rapl_perf idma64 i2c_i801 sg virt_dma pinctrl_sunrisepoint wmi pinctrl_intel acpi_pad intel_lpss_pci intel_lpss mei_me pcc_cpufreq
[52899.160410]  mfd_core intel_pch_thermal mei shpchp ip_tables xfs libcrc32c sd_mod crc32c_intel igb ptp sdhci_pci pps_core sdhci dca i915 ahci i2c_algo_bit mmc_core libahci drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops libata drm video [last unloaded: pcspkr]
[52899.160495] CPU: 0 PID: 21938 Comm: redsocks Tainted: G           O    4.14.64+ #1
[52899.160506] Hardware name: Default string Default string/Default string, BIOS 5.12 07/01/2018
[52899.160518] task: ffff880164d45e00 task.stack: ffffc90002824000
[52899.160536] RIP: 0010:tcp_splice_read+0x225/0x330
[52899.160546] RSP: 0018:ffffc90002827dd8 EFLAGS: 00010286
[52899.160558] RAX: 0000000000000000 RBX: ffff88015b965280 RCX: 0000000000100000
[52899.160569] RDX: ffff88015ba30180 RSI: ffffc90002827ee8 RDI: ffff8801164d82c0
[52899.160579] RBP: ffffc90002827e50 R08: 00000000ffffffff R09: 0000000000000000
[52899.160589] R10: ffff880163940f00 R11: ffff88015ba30180 R12: ffff8801164d82c0
[52899.160599] R13: ffff88015ba30180 R14: ffffc90002827ee8 R15: 0000000000000003
[52899.160611] FS:  00007fae07922740(0000) GS:ffff88016ec00000(0000) knlGS:0000000000000000
[52899.160624] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[52899.160634] CR2: 0000000000000000 CR3: 0000000164c9a006 CR4: 00000000003606f0
[52899.160646] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[52899.160656] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[52899.160664] Call Trace:
[52899.160684]  ? kmem_cache_free+0x1aa/0x1c0
[52899.160702]  sock_splice_read+0x25/0x30
[52899.160719]  do_splice_to+0x76/0x90
[52899.160735]  SyS_splice+0x6fd/0x750
[52899.160750]  ? syscall_trace_enter+0x1cd/0x2b0
[52899.160766]  do_syscall_64+0x79/0x1b0
[52899.160784]  entry_SYSCALL_64_after_hwframe+0x3d/0xa2
[52899.160795] RIP: 0033:0x7fae07213493
[52899.160804] RSP: 002b:00007fff48ffdfe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000113
[52899.160819] RAX: ffffffffffffffda RBX: 00007fff48ffe040 RCX: 00007fae07213493
[52899.160829] RDX: 000000000000008b RSI: 0000000000000000 RDI: 0000000000000081
[52899.160839] RBP: 0000000000000081 R08: 0000000000100000 R09: 0000000000000003
[52899.160849] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000002214d40
[52899.160859] R13: 0000000000000081 R14: 0000000000000002 R15: 00000000022124f0
[52899.160870] Code: ff ff 48 8b 83 d0 07 00 00 48 8b 00 48 85 c0 0f 84 33 fe ff ff 44 8b 05 7a eb d3 00 41 f7 d0 0f 1f 44 00 00 48 8b 80 e8 07 00 00 <48> 8b 00 48 85 c0 75 ec e9 10 fe ff ff 0f b6 43 12 3c 01 0f 85
[52899.161029] RIP: tcp_splice_read+0x225/0x330 RSP: ffffc90002827dd8
[52899.161038] CR2: 0000000000000000

Github-issue: multipath-tcp/mptcp#279

Fixes: ee4f8f6 ("Support tcp_read_sock")
Reported-by: https://github.com/wapsi
Signed-off-by: Christoph Paasch <cpaasch@apple.com>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
(cherry picked from commit 80671d2)
Signed-off-by: Christoph Paasch <cpaasch@apple.com>
mjmartineau pushed a commit that referenced this issue Sep 28, 2018
A kernel crash occurrs when defragmented packet is fragmented
in ip_do_fragment().
In defragment routine, skb_orphan() is called and
skb->ip_defrag_offset is set. but skb->sk and
skb->ip_defrag_offset are same union member. so that
frag->sk is not NULL.
Hence crash occurrs in skb->sk check routine in ip_do_fragment() when
defragmented packet is fragmented.

test commands:
   %iptables -t nat -I POSTROUTING -j MASQUERADE
   %hping3 192.168.4.2 -s 1000 -p 2000 -d 60000

splat looks like:
[  261.069429] kernel BUG at net/ipv4/ip_output.c:636!
[  261.075753] invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI
[  261.083854] CPU: 1 PID: 1349 Comm: hping3 Not tainted 4.19.0-rc2+ #3
[  261.100977] RIP: 0010:ip_do_fragment+0x1613/0x2600
[  261.106945] Code: e8 e2 38 e3 fe 4c 8b 44 24 18 48 8b 74 24 08 e9 92 f6 ff ff 80 3c 02 00 0f 85 da 07 00 00 48 8b b5 d0 00 00 00 e9 25 f6 ff ff <0f> 0b 0f 0b 44 8b 54 24 58 4c 8b 4c 24 18 4c 8b 5c 24 60 4c 8b 6c
[  261.127015] RSP: 0018:ffff8801031cf2c0 EFLAGS: 00010202
[  261.134156] RAX: 1ffff1002297537b RBX: ffffed0020639e6e RCX: 0000000000000004
[  261.142156] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff880114ba9bd8
[  261.150157] RBP: ffff880114ba8a40 R08: ffffed0022975395 R09: ffffed0022975395
[  261.158157] R10: 0000000000000001 R11: ffffed0022975394 R12: ffff880114ba9ca4
[  261.166159] R13: 0000000000000010 R14: ffff880114ba9bc0 R15: dffffc0000000000
[  261.174169] FS:  00007fbae2199700(0000) GS:ffff88011b400000(0000) knlGS:0000000000000000
[  261.183012] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  261.189013] CR2: 00005579244fe000 CR3: 0000000119bf4000 CR4: 00000000001006e0
[  261.198158] Call Trace:
[  261.199018]  ? dst_output+0x180/0x180
[  261.205011]  ? save_trace+0x300/0x300
[  261.209018]  ? ip_copy_metadata+0xb00/0xb00
[  261.213034]  ? sched_clock_local+0xd4/0x140
[  261.218158]  ? kill_l4proto+0x120/0x120 [nf_conntrack]
[  261.223014]  ? rt_cpu_seq_stop+0x10/0x10
[  261.227014]  ? find_held_lock+0x39/0x1c0
[  261.233008]  ip_finish_output+0x51d/0xb50
[  261.237006]  ? ip_fragment.constprop.56+0x220/0x220
[  261.243011]  ? nf_ct_l4proto_register_one+0x5b0/0x5b0 [nf_conntrack]
[  261.250152]  ? rcu_is_watching+0x77/0x120
[  261.255010]  ? nf_nat_ipv4_out+0x1e/0x2b0 [nf_nat_ipv4]
[  261.261033]  ? nf_hook_slow+0xb1/0x160
[  261.265007]  ip_output+0x1c7/0x710
[  261.269005]  ? ip_mc_output+0x13f0/0x13f0
[  261.273002]  ? __local_bh_enable_ip+0xe9/0x1b0
[  261.278152]  ? ip_fragment.constprop.56+0x220/0x220
[  261.282996]  ? nf_hook_slow+0xb1/0x160
[  261.287007]  raw_sendmsg+0x21f9/0x4420
[  261.291008]  ? dst_output+0x180/0x180
[  261.297003]  ? sched_clock_cpu+0x126/0x170
[  261.301003]  ? find_held_lock+0x39/0x1c0
[  261.306155]  ? stop_critical_timings+0x420/0x420
[  261.311004]  ? check_flags.part.36+0x450/0x450
[  261.315005]  ? _raw_spin_unlock_irq+0x29/0x40
[  261.320995]  ? _raw_spin_unlock_irq+0x29/0x40
[  261.326142]  ? cyc2ns_read_end+0x10/0x10
[  261.330139]  ? raw_bind+0x280/0x280
[  261.334138]  ? sched_clock_cpu+0x126/0x170
[  261.338995]  ? check_flags.part.36+0x450/0x450
[  261.342991]  ? __lock_acquire+0x4500/0x4500
[  261.348994]  ? inet_sendmsg+0x11c/0x500
[  261.352989]  ? dst_output+0x180/0x180
[  261.357012]  inet_sendmsg+0x11c/0x500
[ ... ]

v2:
 - clear skb->sk at reassembly routine.(Eric Dumarzet)

Fixes: fa0f527 ("ip: use rb trees for IP frag queue.")
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
mjmartineau pushed a commit that referenced this issue Sep 28, 2018
The following lockdep report can be triggered by writing to /sys/kernel/debug/sched_features:

  ======================================================
  WARNING: possible circular locking dependency detected
  4.18.0-rc6-00152-gcd3f77d74ac3-dirty #18 Not tainted
  ------------------------------------------------------
  sh/3358 is trying to acquire lock:
  000000004ad3989d (cpu_hotplug_lock.rw_sem){++++}, at: static_key_enable+0x14/0x30
  but task is already holding lock:
  00000000c1b31a88 (&sb->s_type->i_mutex_key#3){+.+.}, at: sched_feat_write+0x160/0x428
  which lock already depends on the new lock.
  the existing dependency chain (in reverse order) is:
  -> #3 (&sb->s_type->i_mutex_key#3){+.+.}:
         lock_acquire+0xb8/0x148
         down_write+0xac/0x140
         start_creating+0x5c/0x168
         debugfs_create_dir+0x18/0x220
         opp_debug_register+0x8c/0x120
         _add_opp_dev+0x104/0x1f8
         dev_pm_opp_get_opp_table+0x174/0x340
         _of_add_opp_table_v2+0x110/0x760
         dev_pm_opp_of_add_table+0x5c/0x240
         dev_pm_opp_of_cpumask_add_table+0x5c/0x100
         cpufreq_init+0x160/0x430
         cpufreq_online+0x1cc/0xe30
         cpufreq_add_dev+0x78/0x198
         subsys_interface_register+0x168/0x270
         cpufreq_register_driver+0x1c8/0x278
         dt_cpufreq_probe+0xdc/0x1b8
         platform_drv_probe+0xb4/0x168
         driver_probe_device+0x318/0x4b0
         __device_attach_driver+0xfc/0x1f0
         bus_for_each_drv+0xf8/0x180
         __device_attach+0x164/0x200
         device_initial_probe+0x10/0x18
         bus_probe_device+0x110/0x178
         device_add+0x6d8/0x908
         platform_device_add+0x138/0x3d8
         platform_device_register_full+0x1cc/0x1f8
         cpufreq_dt_platdev_init+0x174/0x1bc
         do_one_initcall+0xb8/0x310
         kernel_init_freeable+0x4b8/0x56c
         kernel_init+0x10/0x138
         ret_from_fork+0x10/0x18
  -> #2 (opp_table_lock){+.+.}:
         lock_acquire+0xb8/0x148
         __mutex_lock+0x104/0xf50
         mutex_lock_nested+0x1c/0x28
         _of_add_opp_table_v2+0xb4/0x760
         dev_pm_opp_of_add_table+0x5c/0x240
         dev_pm_opp_of_cpumask_add_table+0x5c/0x100
         cpufreq_init+0x160/0x430
         cpufreq_online+0x1cc/0xe30
         cpufreq_add_dev+0x78/0x198
         subsys_interface_register+0x168/0x270
         cpufreq_register_driver+0x1c8/0x278
         dt_cpufreq_probe+0xdc/0x1b8
         platform_drv_probe+0xb4/0x168
         driver_probe_device+0x318/0x4b0
         __device_attach_driver+0xfc/0x1f0
         bus_for_each_drv+0xf8/0x180
         __device_attach+0x164/0x200
         device_initial_probe+0x10/0x18
         bus_probe_device+0x110/0x178
         device_add+0x6d8/0x908
         platform_device_add+0x138/0x3d8
         platform_device_register_full+0x1cc/0x1f8
         cpufreq_dt_platdev_init+0x174/0x1bc
         do_one_initcall+0xb8/0x310
         kernel_init_freeable+0x4b8/0x56c
         kernel_init+0x10/0x138
         ret_from_fork+0x10/0x18
  -> #1 (subsys mutex#6){+.+.}:
         lock_acquire+0xb8/0x148
         __mutex_lock+0x104/0xf50
         mutex_lock_nested+0x1c/0x28
         subsys_interface_register+0xd8/0x270
         cpufreq_register_driver+0x1c8/0x278
         dt_cpufreq_probe+0xdc/0x1b8
         platform_drv_probe+0xb4/0x168
         driver_probe_device+0x318/0x4b0
         __device_attach_driver+0xfc/0x1f0
         bus_for_each_drv+0xf8/0x180
         __device_attach+0x164/0x200
         device_initial_probe+0x10/0x18
         bus_probe_device+0x110/0x178
         device_add+0x6d8/0x908
         platform_device_add+0x138/0x3d8
         platform_device_register_full+0x1cc/0x1f8
         cpufreq_dt_platdev_init+0x174/0x1bc
         do_one_initcall+0xb8/0x310
         kernel_init_freeable+0x4b8/0x56c
         kernel_init+0x10/0x138
         ret_from_fork+0x10/0x18
  -> #0 (cpu_hotplug_lock.rw_sem){++++}:
         __lock_acquire+0x203c/0x21d0
         lock_acquire+0xb8/0x148
         cpus_read_lock+0x58/0x1c8
         static_key_enable+0x14/0x30
         sched_feat_write+0x314/0x428
         full_proxy_write+0xa0/0x138
         __vfs_write+0xd8/0x388
         vfs_write+0xdc/0x318
         ksys_write+0xb4/0x138
         sys_write+0xc/0x18
         __sys_trace_return+0x0/0x4
  other info that might help us debug this:
  Chain exists of:
    cpu_hotplug_lock.rw_sem --> opp_table_lock --> &sb->s_type->i_mutex_key#3
   Possible unsafe locking scenario:
         CPU0                    CPU1
         ----                    ----
    lock(&sb->s_type->i_mutex_key#3);
                                 lock(opp_table_lock);
                                 lock(&sb->s_type->i_mutex_key#3);
    lock(cpu_hotplug_lock.rw_sem);
   *** DEADLOCK ***
  2 locks held by sh/3358:
   #0: 00000000a8c4b363 (sb_writers#10){.+.+}, at: vfs_write+0x238/0x318
   #1: 00000000c1b31a88 (&sb->s_type->i_mutex_key#3){+.+.}, at: sched_feat_write+0x160/0x428
  stack backtrace:
  CPU: 5 PID: 3358 Comm: sh Not tainted 4.18.0-rc6-00152-gcd3f77d74ac3-dirty #18
  Hardware name: Renesas H3ULCB Kingfisher board based on r8a7795 ES2.0+ (DT)
  Call trace:
   dump_backtrace+0x0/0x288
   show_stack+0x14/0x20
   dump_stack+0x13c/0x1ac
   print_circular_bug.isra.10+0x270/0x438
   check_prev_add.constprop.16+0x4dc/0xb98
   __lock_acquire+0x203c/0x21d0
   lock_acquire+0xb8/0x148
   cpus_read_lock+0x58/0x1c8
   static_key_enable+0x14/0x30
   sched_feat_write+0x314/0x428
   full_proxy_write+0xa0/0x138
   __vfs_write+0xd8/0x388
   vfs_write+0xdc/0x318
   ksys_write+0xb4/0x138
   sys_write+0xc/0x18
   __sys_trace_return+0x0/0x4

This is because when loading the cpufreq_dt module we first acquire
cpu_hotplug_lock.rw_sem lock, then in cpufreq_init(), we are taking
the &sb->s_type->i_mutex_key lock.

But when writing to /sys/kernel/debug/sched_features, the
cpu_hotplug_lock.rw_sem lock depends on the &sb->s_type->i_mutex_key lock.

To fix this bug, reverse the lock acquisition order when writing to
sched_features, this way cpu_hotplug_lock.rw_sem no longer depends on
&sb->s_type->i_mutex_key.

Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Eugeniu Rosca <erosca@de.adit-jv.com>
Cc: George G. Davis <george_davis@mentor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180731121222.26195-1-jiada_wang@mentor.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
mjmartineau pushed a commit that referenced this issue Sep 28, 2018
In case local OOB data was generated and other device initiated pairing
claiming that it has got OOB data, following crash occurred:

[  222.847853] general protection fault: 0000 [#1] SMP PTI
[  222.848025] CPU: 1 PID: 42 Comm: kworker/u5:0 Tainted: G         C        4.18.0-custom #4
[  222.848158] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[  222.848307] Workqueue: hci0 hci_rx_work [bluetooth]
[  222.848416] RIP: 0010:compute_ecdh_secret+0x5a/0x270 [bluetooth]
[  222.848540] Code: 0c af f5 48 8b 3d 46 de f0 f6 ba 40 00 00 00 be c0 00 60 00 e8 b7 7b c5 f5 48 85 c0 0f 84 ea 01 00 00 48 89 c3 e8 16 0c af f5 <49> 8b 47 38 be c0 00 60 00 8b 78 f8 48 83 c7 48 e8 51 84 c5 f5 48
[  222.848914] RSP: 0018:ffffb1664087fbc0 EFLAGS: 00010293
[  222.849021] RAX: ffff8a5750d7dc00 RBX: ffff8a5671096780 RCX: ffffffffc08bc32a
[  222.849111] RDX: 0000000000000000 RSI: 00000000006000c0 RDI: ffff8a5752003800
[  222.849192] RBP: ffffb1664087fc60 R08: ffff8a57525280a0 R09: ffff8a5752003800
[  222.849269] R10: ffffb1664087fc70 R11: 0000000000000093 R12: ffff8a5674396e00
[  222.849350] R13: ffff8a574c2e79aa R14: ffff8a574c2e796a R15: 020e0e100d010101
[  222.849429] FS:  0000000000000000(0000) GS:ffff8a5752500000(0000) knlGS:0000000000000000
[  222.849518] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  222.849586] CR2: 000055856016a038 CR3: 0000000110d2c005 CR4: 00000000000606e0
[  222.849671] Call Trace:
[  222.849745]  ? sc_send_public_key+0x110/0x2a0 [bluetooth]
[  222.849825]  ? sc_send_public_key+0x115/0x2a0 [bluetooth]
[  222.849925]  smp_recv_cb+0x959/0x2490 [bluetooth]
[  222.850023]  ? _cond_resched+0x19/0x40
[  222.850105]  ? mutex_lock+0x12/0x40
[  222.850202]  l2cap_recv_frame+0x109d/0x3420 [bluetooth]
[  222.850315]  ? l2cap_recv_frame+0x109d/0x3420 [bluetooth]
[  222.850426]  ? __switch_to_asm+0x34/0x70
[  222.850515]  ? __switch_to_asm+0x40/0x70
[  222.850625]  ? __switch_to_asm+0x34/0x70
[  222.850724]  ? __switch_to_asm+0x40/0x70
[  222.850786]  ? __switch_to_asm+0x34/0x70
[  222.850846]  ? __switch_to_asm+0x40/0x70
[  222.852581]  ? __switch_to_asm+0x34/0x70
[  222.854976]  ? __switch_to_asm+0x40/0x70
[  222.857475]  ? __switch_to_asm+0x40/0x70
[  222.859775]  ? __switch_to_asm+0x34/0x70
[  222.861218]  ? __switch_to_asm+0x40/0x70
[  222.862327]  ? __switch_to_asm+0x34/0x70
[  222.863758]  l2cap_recv_acldata+0x266/0x3c0 [bluetooth]
[  222.865122]  hci_rx_work+0x1c9/0x430 [bluetooth]
[  222.867144]  process_one_work+0x210/0x4c0
[  222.868248]  worker_thread+0x41/0x4d0
[  222.869420]  kthread+0x141/0x160
[  222.870694]  ? process_one_work+0x4c0/0x4c0
[  222.871668]  ? kthread_create_worker_on_cpu+0x90/0x90
[  222.872896]  ret_from_fork+0x35/0x40
[  222.874132] Modules linked in: algif_hash algif_skcipher af_alg rfcomm bnep btusb btrtl btbcm btintel snd_intel8x0 cmac intel_rapl_perf vboxvideo(C) snd_ac97_codec bluetooth ac97_bus joydev ttm snd_pcm ecdh_generic drm_kms_helper snd_timer snd input_leds drm serio_raw fb_sys_fops soundcore syscopyarea sysfillrect sysimgblt mac_hid sch_fq_codel ib_iser rdma_cm iw_cm ib_cm ib_core iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi ip_tables x_tables autofs4 btrfs zstd_compress raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c raid1 raid0 multipath linear hid_generic usbhid hid crct10dif_pclmul crc32_pclmul ghash_clmulni_intel pcbc aesni_intel aes_x86_64 crypto_simd cryptd glue_helper ahci psmouse libahci i2c_piix4 video e1000 pata_acpi
[  222.883153] fbcon_switch: detected unhandled fb_set_par error, error code -16
[  222.886774] fbcon_switch: detected unhandled fb_set_par error, error code -16
[  222.890503] ---[ end trace 6504aa7a777b5316 ]---
[  222.890541] RIP: 0010:compute_ecdh_secret+0x5a/0x270 [bluetooth]
[  222.890551] Code: 0c af f5 48 8b 3d 46 de f0 f6 ba 40 00 00 00 be c0 00 60 00 e8 b7 7b c5 f5 48 85 c0 0f 84 ea 01 00 00 48 89 c3 e8 16 0c af f5 <49> 8b 47 38 be c0 00 60 00 8b 78 f8 48 83 c7 48 e8 51 84 c5 f5 48
[  222.890555] RSP: 0018:ffffb1664087fbc0 EFLAGS: 00010293
[  222.890561] RAX: ffff8a5750d7dc00 RBX: ffff8a5671096780 RCX: ffffffffc08bc32a
[  222.890565] RDX: 0000000000000000 RSI: 00000000006000c0 RDI: ffff8a5752003800
[  222.890571] RBP: ffffb1664087fc60 R08: ffff8a57525280a0 R09: ffff8a5752003800
[  222.890576] R10: ffffb1664087fc70 R11: 0000000000000093 R12: ffff8a5674396e00
[  222.890581] R13: ffff8a574c2e79aa R14: ffff8a574c2e796a R15: 020e0e100d010101
[  222.890586] FS:  0000000000000000(0000) GS:ffff8a5752500000(0000) knlGS:0000000000000000
[  222.890591] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  222.890594] CR2: 000055856016a038 CR3: 0000000110d2c005 CR4: 00000000000606e0

This commit fixes a bug where invalid pointer to crypto tfm was used for
SMP SC ECDH calculation when OOB was in use. Solution is to use same
crypto tfm than when generating OOB material on generate_oob() function.

This bug was introduced in commit c0153b0 ("Bluetooth: let the crypto
subsystem generate the ecc privkey"). Bug was found by fuzzing kernel SMP
implementation using Synopsys Defensics.

Signed-off-by: Matias Karhumaa <matias.karhumaa@gmail.com>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
mjmartineau pushed a commit that referenced this issue Sep 28, 2018
Yonghong Song says:

====================
The support to dump program array and map_in_map maps
for bpffs and bpftool is added. Patch #1 added bpffs support
and Patch #2 added bpftool support. Please see
individual patches for example output.
====================

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
mjmartineau pushed a commit that referenced this issue Sep 28, 2018
There is RaceFuzzer report like below because we have no lock to close
below the race between binder_mmap and binder_alloc_new_buf_locked.
To close the race, let's use memory barrier so that if someone see
alloc->vma is not NULL, alloc->vma_vm_mm should be never NULL.

(I didn't add stable mark intentionallybecause standard android
userspace libraries that interact with binder (libbinder & libhwbinder)
prevent the mmap/ioctl race. - from Todd)

"
Thread interleaving:
CPU0 (binder_alloc_mmap_handler)              CPU1 (binder_alloc_new_buf_locked)
=====                                         =====
// drivers/android/binder_alloc.c
// #L718 (v4.18-rc3)
alloc->vma = vma;
                                              // drivers/android/binder_alloc.c
                                              // #L346 (v4.18-rc3)
                                              if (alloc->vma == NULL) {
                                                  ...
                                                  // alloc->vma is not NULL at this point
                                                  return ERR_PTR(-ESRCH);
                                              }
                                              ...
                                              // #L438
                                              binder_update_page_range(alloc, 0,
                                                      (void *)PAGE_ALIGN((uintptr_t)buffer->data),
                                                      end_page_addr);

                                              // In binder_update_page_range() #L218
                                              // But still alloc->vma_vm_mm is NULL here
                                              if (need_mm && mmget_not_zero(alloc->vma_vm_mm))
alloc->vma_vm_mm = vma->vm_mm;

Crash Log:
==================================================================
BUG: KASAN: null-ptr-deref in __atomic_add_unless include/asm-generic/atomic-instrumented.h:89 [inline]
BUG: KASAN: null-ptr-deref in atomic_add_unless include/linux/atomic.h:533 [inline]
BUG: KASAN: null-ptr-deref in mmget_not_zero include/linux/sched/mm.h:75 [inline]
BUG: KASAN: null-ptr-deref in binder_update_page_range+0xece/0x18e0 drivers/android/binder_alloc.c:218
Write of size 4 at addr 0000000000000058 by task syz-executor0/11184

CPU: 1 PID: 11184 Comm: syz-executor0 Not tainted 4.18.0-rc3 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.8.2-0-g33fbe13 by qemu-project.org 04/01/2014
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x16e/0x22c lib/dump_stack.c:113
 kasan_report_error mm/kasan/report.c:352 [inline]
 kasan_report+0x163/0x380 mm/kasan/report.c:412
 check_memory_region_inline mm/kasan/kasan.c:260 [inline]
 check_memory_region+0x140/0x1a0 mm/kasan/kasan.c:267
 kasan_check_write+0x14/0x20 mm/kasan/kasan.c:278
 __atomic_add_unless include/asm-generic/atomic-instrumented.h:89 [inline]
 atomic_add_unless include/linux/atomic.h:533 [inline]
 mmget_not_zero include/linux/sched/mm.h:75 [inline]
 binder_update_page_range+0xece/0x18e0 drivers/android/binder_alloc.c:218
 binder_alloc_new_buf_locked drivers/android/binder_alloc.c:443 [inline]
 binder_alloc_new_buf+0x467/0xc30 drivers/android/binder_alloc.c:513
 binder_transaction+0x125b/0x4fb0 drivers/android/binder.c:2957
 binder_thread_write+0xc08/0x2770 drivers/android/binder.c:3528
 binder_ioctl_write_read.isra.39+0x24f/0x8e0 drivers/android/binder.c:4456
 binder_ioctl+0xa86/0xf34 drivers/android/binder.c:4596
 vfs_ioctl fs/ioctl.c:46 [inline]
 do_vfs_ioctl+0x154/0xd40 fs/ioctl.c:686
 ksys_ioctl+0x94/0xb0 fs/ioctl.c:701
 __do_sys_ioctl fs/ioctl.c:708 [inline]
 __se_sys_ioctl fs/ioctl.c:706 [inline]
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:706
 do_syscall_64+0x167/0x4b0 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
"

Signed-off-by: Todd Kjos <tkjos@google.com>
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: Martijn Coenen <maco@android.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mjmartineau pushed a commit that referenced this issue Sep 28, 2018
This reverts commit 12eeeb4.

The patch doesn't fix accessing memory with null pointer in
skl_interrupt().

There are two problems: 1) skl_init_chip() is called twice, before
and after dma buffer is allocate. The first call sets bus->chip_init
which prevents the second from initializing bus->corb.buf and
rirb.buf from bus->rb.area. 2) snd_hdac_bus_init_chip() enables
interrupt before snd_hdac_bus_init_cmd_io() initializing dma buffers.
There is a small window which skl_interrupt() can be called if irq
has been acquired. If so, it crashes when using null dma buffer
pointers.

Will fix the problems in the following patches. Also attaching the
crash for future reference.

[   16.949148] general protection fault: 0000 [#1] PREEMPT SMP KASAN PTI
<snipped>
[   16.950903] Call Trace:
[   16.950906]  <IRQ>
[   16.950918]  skl_interrupt+0x19e/0x2d6 [snd_soc_skl]
[   16.950926]  ? dma_supported+0xb5/0xb5 [snd_soc_skl]
[   16.950933]  __handle_irq_event_percpu+0x27a/0x6c8
[   16.950937]  ? __irq_wake_thread+0x1d1/0x1d1
[   16.950942]  ? __do_softirq+0x57a/0x69e
[   16.950944]  handle_irq_event_percpu+0x95/0x1ba
[   16.950948]  ? _raw_spin_unlock+0x65/0xdc
[   16.950951]  ? __handle_irq_event_percpu+0x6c8/0x6c8
[   16.950953]  ? _raw_spin_unlock+0x65/0xdc
[   16.950957]  ? time_cpufreq_notifier+0x483/0x483
[   16.950959]  handle_irq_event+0x89/0x123
[   16.950962]  handle_fasteoi_irq+0x16f/0x425
[   16.950965]  handle_irq+0x1fe/0x28e
[   16.950969]  do_IRQ+0x6e/0x12e
[   16.950972]  common_interrupt+0x7a/0x7a
[   16.950974]  </IRQ>
<snipped>
[   16.951031] RIP: snd_hdac_bus_update_rirb+0x19b/0x4cf [snd_hda_core] RSP: ffff88015c807c08
[   16.951036] ---[ end trace 58bf9ece1775bc92 ]---

Fixes: 2eeeb4f4733b ("ASoC: Intel: Skylake: Acquire irq after RIRB allocation")
Signed-off-by: Yu Zhao <yuzhao@google.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
mjmartineau pushed a commit that referenced this issue Sep 28, 2018
When netvsc device is removed it can call reschedule in RCU context.
This happens because canceling the subchannel setup work could (in theory)
cause a reschedule when manipulating the timer.

To reproduce, run with lockdep enabled kernel and unbind
a network device from hv_netvsc (via sysfs).

[  160.682011] WARNING: suspicious RCU usage
[  160.707466] 4.19.0-rc3-uio+ #2 Not tainted
[  160.709937] -----------------------------
[  160.712352] ./include/linux/rcupdate.h:302 Illegal context switch in RCU read-side critical section!
[  160.723691]
[  160.723691] other info that might help us debug this:
[  160.723691]
[  160.730955]
[  160.730955] rcu_scheduler_active = 2, debug_locks = 1
[  160.762813] 5 locks held by rebind-eth.sh/1812:
[  160.766851]  #0: 000000008befa37a (sb_writers#6){.+.+}, at: vfs_write+0x184/0x1b0
[  160.773416]  #1: 00000000b097f236 (&of->mutex){+.+.}, at: kernfs_fop_write+0xe2/0x1a0
[  160.783766]  #2: 0000000041ee6889 (kn->count#3){++++}, at: kernfs_fop_write+0xeb/0x1a0
[  160.787465]  #3: 0000000056d92a74 (&dev->mutex){....}, at: device_release_driver_internal+0x39/0x250
[  160.816987]  #4: 0000000030f6031e (rcu_read_lock){....}, at: netvsc_remove+0x1e/0x250 [hv_netvsc]
[  160.828629]
[  160.828629] stack backtrace:
[  160.831966] CPU: 1 PID: 1812 Comm: rebind-eth.sh Not tainted 4.19.0-rc3-uio+ #2
[  160.832952] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v1.0 11/26/2012
[  160.832952] Call Trace:
[  160.832952]  dump_stack+0x85/0xcb
[  160.832952]  ___might_sleep+0x1a3/0x240
[  160.832952]  __flush_work+0x57/0x2e0
[  160.832952]  ? __mutex_lock+0x83/0x990
[  160.832952]  ? __kernfs_remove+0x24f/0x2e0
[  160.832952]  ? __kernfs_remove+0x1b2/0x2e0
[  160.832952]  ? mark_held_locks+0x50/0x80
[  160.832952]  ? get_work_pool+0x90/0x90
[  160.832952]  __cancel_work_timer+0x13c/0x1e0
[  160.832952]  ? netvsc_remove+0x1e/0x250 [hv_netvsc]
[  160.832952]  ? __lock_is_held+0x55/0x90
[  160.832952]  netvsc_remove+0x9a/0x250 [hv_netvsc]
[  160.832952]  vmbus_remove+0x26/0x30
[  160.832952]  device_release_driver_internal+0x18a/0x250
[  160.832952]  unbind_store+0xb4/0x180
[  160.832952]  kernfs_fop_write+0x113/0x1a0
[  160.832952]  __vfs_write+0x36/0x1a0
[  160.832952]  ? rcu_read_lock_sched_held+0x6b/0x80
[  160.832952]  ? rcu_sync_lockdep_assert+0x2e/0x60
[  160.832952]  ? __sb_start_write+0x141/0x1a0
[  160.832952]  ? vfs_write+0x184/0x1b0
[  160.832952]  vfs_write+0xbe/0x1b0
[  160.832952]  ksys_write+0x55/0xc0
[  160.832952]  do_syscall_64+0x60/0x1b0
[  160.832952]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
[  160.832952] RIP: 0033:0x7fe48f4c8154

Resolve this by getting RTNL earlier. This is safe because the subchannel
work queue does trylock on RTNL and will detect the race.

Fixes: 7b2ee50 ("hv_netvsc: common detach logic")
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
mjmartineau pushed a commit that referenced this issue Sep 28, 2018
The command 'xl vcpu-set 0 0', issued in dom0, will crash dom0:

BUG: unable to handle kernel NULL pointer dereference at 00000000000002d8
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP NOPTI
CPU: 7 PID: 65 Comm: xenwatch Not tainted 4.19.0-rc2-1.ga9462db-default #1 openSUSE Tumbleweed (unreleased)
Hardware name: Intel Corporation S5520UR/S5520UR, BIOS S5500.86B.01.00.0050.050620101605 05/06/2010
RIP: e030:device_offline+0x9/0xb0
Code: 77 24 00 e9 ce fe ff ff 48 8b 13 e9 68 ff ff ff 48 8b 13 e9 29 ff ff ff 48 8b 13 e9 ea fe ff ff 90 66 66 66 66 90 41 54 55 53 <f6> 87 d8 02 00 00 01 0f 85 88 00 00 00 48 c7 c2 20 09 60 81 31 f6
RSP: e02b:ffffc90040f27e80 EFLAGS: 00010203
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffff8801f3800000 RSI: ffffc90040f27e70 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffff820e47b3 R09: 0000000000000000
R10: 0000000000007ff0 R11: 0000000000000000 R12: ffffffff822e6d30
R13: dead000000000200 R14: dead000000000100 R15: ffffffff8158b4e0
FS:  00007ffa595158c0(0000) GS:ffff8801f39c0000(0000) knlGS:0000000000000000
CS:  e033 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000000002d8 CR3: 00000001d9602000 CR4: 0000000000002660
Call Trace:
 handle_vcpu_hotplug_event+0xb5/0xc0
 xenwatch_thread+0x80/0x140
 ? wait_woken+0x80/0x80
 kthread+0x112/0x130
 ? kthread_create_worker_on_cpu+0x40/0x40
 ret_from_fork+0x3a/0x50

This happens because handle_vcpu_hotplug_event is called twice. In the
first iteration cpu_present is still true, in the second iteration
cpu_present is false which causes get_cpu_device to return NULL.
In case of cpu#0, cpu_online is apparently always true.

Fix this crash by checking if the cpu can be hotplugged, which is false
for a cpu that was just removed.

Also check if the cpu was actually offlined by device_remove, otherwise
leave the cpu_present state as it is.

Rearrange to code to do all work with device_hotplug_lock held.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
mjmartineau pushed a commit that referenced this issue Sep 28, 2018
…inux-nfs

Pull NFS client bugfixes from Anna Schumaker:
 "These are a handful of fixes for problems that Trond found. Patch #1
  and #3 have the same name, a second issue was found after applying the
  first patch.

  Stable bugfixes:
   - v4.17+: Fix tracepoint Oops in initiate_file_draining()
   - v4.11+: Fix an infinite loop on I/O

  Other fixes:
   - Return errors if a waiting layoutget is killed
   - Don't open code clearing of delegation state"

* tag 'nfs-for-4.19-2' of git://git.linux-nfs.org/projects/anna/linux-nfs:
  NFS: Don't open code clearing of delegation state
  NFSv4.1 fix infinite loop on I/O.
  NFSv4: Fix a tracepoint Oops in initiate_file_draining()
  pNFS: Ensure we return the error if someone kills a waiting layoutget
  NFSv4: Fix a tracepoint Oops in initiate_file_draining()
mjmartineau pushed a commit that referenced this issue Sep 28, 2018
Chen Yu reported a divide-by-zero error when accessing the 'size'
resctrl file when a MBA resource is enabled.

divide error: 0000 [#1] SMP PTI
CPU: 93 PID: 1929 Comm: cat Not tainted 4.19.0-rc2-debug-rdt+ #25
RIP: 0010:rdtgroup_cbm_to_size+0x7e/0xa0
Call Trace:
rdtgroup_size_show+0x11a/0x1d0
seq_read+0xd8/0x3b0

Quoting Chen Yu's report: This is because for MB resource, the
r->cache.cbm_len is zero, thus calculating size in rdtgroup_cbm_to_size()
will trigger the exception.

Fix this issue in the 'size' file by getting correct memory bandwidth value
which is in MBps when MBA software controller is enabled or in percentage
when MBA software controller is disabled.

Fixes: d9b48c8 ("x86/intel_rdt: Display resource groups' allocations in bytes")
Reported-by: Chen Yu <yu.c.chen@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Chen Yu <yu.c.chen@intel.com>
Cc: "H Peter Anvin" <hpa@zytor.com>
Cc: "Tony Luck" <tony.luck@intel.com>
Cc: "Xiaochen Shen" <xiaochen.shen@intel.com>
Link: https://lkml.kernel.org/r/20180904174614.26682-1-yu.c.chen@intel.com
Link: https://lkml.kernel.org/r/1537048707-76280-3-git-send-email-fenghua.yu@intel.com
matttbe pushed a commit that referenced this issue Aug 30, 2024
Ethtool callbacks can be executed while reset is in progress and try to
access deleted resources, e.g. getting coalesce settings can result in a
NULL pointer dereference seen below.

Reproduction steps:
Once the driver is fully initialized, trigger reset:
	# echo 1 > /sys/class/net/<interface>/device/reset
when reset is in progress try to get coalesce settings using ethtool:
	# ethtool -c <interface>

BUG: kernel NULL pointer dereference, address: 0000000000000020
PGD 0 P4D 0
Oops: Oops: 0000 [#1] PREEMPT SMP PTI
CPU: 11 PID: 19713 Comm: ethtool Tainted: G S                 6.10.0-rc7+ #7
RIP: 0010:ice_get_q_coalesce+0x2e/0xa0 [ice]
RSP: 0018:ffffbab1e9bcf6a8 EFLAGS: 00010206
RAX: 000000000000000c RBX: ffff94512305b028 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff9451c3f2e588 RDI: ffff9451c3f2e588
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: ffff9451c3f2e580 R11: 000000000000001f R12: ffff945121fa9000
R13: ffffbab1e9bcf760 R14: 0000000000000013 R15: ffffffff9e65dd40
FS:  00007faee5fbe740(0000) GS:ffff94546fd80000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000020 CR3: 0000000106c2e005 CR4: 00000000001706f0
Call Trace:
<TASK>
ice_get_coalesce+0x17/0x30 [ice]
coalesce_prepare_data+0x61/0x80
ethnl_default_doit+0xde/0x340
genl_family_rcv_msg_doit+0xf2/0x150
genl_rcv_msg+0x1b3/0x2c0
netlink_rcv_skb+0x5b/0x110
genl_rcv+0x28/0x40
netlink_unicast+0x19c/0x290
netlink_sendmsg+0x222/0x490
__sys_sendto+0x1df/0x1f0
__x64_sys_sendto+0x24/0x30
do_syscall_64+0x82/0x160
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7faee60d8e27

Calling netif_device_detach() before reset makes the net core not call
the driver when ethtool command is issued, the attempt to execute an
ethtool command during reset will result in the following message:

    netlink error: No such device

instead of NULL pointer dereference. Once reset is done and
ice_rebuild() is executing, the netif_device_attach() is called to allow
for ethtool operations to occur again in a safe manner.

Fixes: fcea6f3 ("ice: Add stats and ethtool support")
Suggested-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Igor Bagnucki <igor.bagnucki@intel.com>
Signed-off-by: Dawid Osuchowski <dawid.osuchowski@linux.intel.com>
Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@intel.com> (A Contingent worker at Intel)
Reviewed-by: Michal Schmidt <mschmidt@redhat.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
matttbe pushed a commit that referenced this issue Sep 2, 2024
When we cork messages in psock->cork, the last message triggers the
flushing will result in sending a sk_msg larger than the current
message size. In this case, in tcp_bpf_send_verdict(), 'copied' becomes
negative at least in the following case:

468         case __SK_DROP:
469         default:
470                 sk_msg_free_partial(sk, msg, tosend);
471                 sk_msg_apply_bytes(psock, tosend);
472                 *copied -= (tosend + delta); // <==== HERE
473                 return -EACCES;

Therefore, it could lead to the following BUG with a proper value of
'copied' (thanks to syzbot). We should not use negative 'copied' as a
return value here.

  ------------[ cut here ]------------
  kernel BUG at net/socket.c:733!
  Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
  Modules linked in:
  CPU: 0 UID: 0 PID: 3265 Comm: syz-executor510 Not tainted 6.11.0-rc3-syzkaller-00060-gd07b43284ab3 #0
  Hardware name: linux,dummy-virt (DT)
  pstate: 61400009 (nZCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--)
  pc : sock_sendmsg_nosec net/socket.c:733 [inline]
  pc : sock_sendmsg_nosec net/socket.c:728 [inline]
  pc : __sock_sendmsg+0x5c/0x60 net/socket.c:745
  lr : sock_sendmsg_nosec net/socket.c:730 [inline]
  lr : __sock_sendmsg+0x54/0x60 net/socket.c:745
  sp : ffff800088ea3b30
  x29: ffff800088ea3b30 x28: fbf00000062bc900 x27: 0000000000000000
  x26: ffff800088ea3bc0 x25: ffff800088ea3bc0 x24: 0000000000000000
  x23: f9f00000048dc000 x22: 0000000000000000 x21: ffff800088ea3d90
  x20: f9f00000048dc000 x19: ffff800088ea3d90 x18: 0000000000000001
  x17: 0000000000000000 x16: 0000000000000000 x15: 000000002002ffaf
  x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000
  x11: 0000000000000000 x10: ffff8000815849c0 x9 : ffff8000815b49c0
  x8 : 0000000000000000 x7 : 000000000000003f x6 : 0000000000000000
  x5 : 00000000000007e0 x4 : fff07ffffd239000 x3 : fbf00000062bc900
  x2 : 0000000000000000 x1 : 0000000000000000 x0 : 00000000fffffdef
  Call trace:
   sock_sendmsg_nosec net/socket.c:733 [inline]
   __sock_sendmsg+0x5c/0x60 net/socket.c:745
   ____sys_sendmsg+0x274/0x2ac net/socket.c:2597
   ___sys_sendmsg+0xac/0x100 net/socket.c:2651
   __sys_sendmsg+0x84/0xe0 net/socket.c:2680
   __do_sys_sendmsg net/socket.c:2689 [inline]
   __se_sys_sendmsg net/socket.c:2687 [inline]
   __arm64_sys_sendmsg+0x24/0x30 net/socket.c:2687
   __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
   invoke_syscall+0x48/0x110 arch/arm64/kernel/syscall.c:49
   el0_svc_common.constprop.0+0x40/0xe0 arch/arm64/kernel/syscall.c:132
   do_el0_svc+0x1c/0x28 arch/arm64/kernel/syscall.c:151
   el0_svc+0x34/0xec arch/arm64/kernel/entry-common.c:712
   el0t_64_sync_handler+0x100/0x12c arch/arm64/kernel/entry-common.c:730
   el0t_64_sync+0x19c/0x1a0 arch/arm64/kernel/entry.S:598
  Code: f9404463 d63f0060 3108441f 54fffe81 (d4210000)
  ---[ end trace 0000000000000000 ]---

Fixes: 4f738ad ("bpf: create tcp_bpf_ulp allowing BPF to monitor socket TX/RX data")
Reported-by: syzbot+58c03971700330ce14d8@syzkaller.appspotmail.com
Cc: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://patch.msgid.link/20240821030744.320934-1-xiyou.wangcong@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
matttbe pushed a commit that referenced this issue Sep 2, 2024
Ido Schimmel says:

====================
Unmask upper DSCP bits - part 2

tl;dr - This patchset continues to unmask the upper DSCP bits in the
IPv4 flow key in preparation for allowing IPv4 FIB rules to match on
DSCP. No functional changes are expected. Part 1 was merged in commit
("Merge branch 'unmask-upper-dscp-bits-part-1'").

The TOS field in the IPv4 flow key ('flowi4_tos') is used during FIB
lookup to match against the TOS selector in FIB rules and routes.

It is currently impossible for user space to configure FIB rules that
match on the DSCP value as the upper DSCP bits are either masked in the
various call sites that initialize the IPv4 flow key or along the path
to the FIB core.

In preparation for adding a DSCP selector to IPv4 and IPv6 FIB rules, we
need to make sure the entire DSCP value is present in the IPv4 flow key.
This patchset continues to unmask the upper DSCP bits, but this time in
the output route path.

Patches #1-#3 unmask the upper DSCP bits in the various places that
invoke the core output route lookup functions directly.

Patches #4-#6 do the same in three helpers that are widely used in the
output path to initialize the TOS field in the IPv4 flow key.

The rest of the patches continue to unmask these bits in call sites that
invoke the following wrappers around the core lookup functions:

Patch #7 - __ip_route_output_key()
Patches #8-#12 - ip_route_output_flow()

The next patchset will handle the callers of ip_route_output_ports() and
ip_route_output_key().

No functional changes are expected as commit 1fa3314 ("ipv4:
Centralize TOS matching") moved the masking of the upper DSCP bits to
the core where 'flowi4_tos' is matched against the TOS selector.

Changes since v1 [1]:

* Remove IPTOS_RT_MASK in patch #7 instead of in patch #6

[1] https://lore.kernel.org/netdev/20240827111813.2115285-1-idosch@nvidia.com/
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
matttbe pushed a commit that referenced this issue Sep 4, 2024
Daniel Machon says:

====================
net: microchip: add FDMA library and use it for Sparx5

This patch series is the first of a 2-part series, that adds a new
common FDMA library for Microchip switch chips Sparx5 and lan966x. These
chips share the same FDMA engine, and as such will benefit from a
common library with a common implementation.  This also has the benefit
of removing a lot open-coded bookkeeping and duplicate code for the two
drivers.

Additionally, upstreaming efforts for a third chip, lan969x, will begin
in the near future. This chip will use the new library too.

In this first series, the FDMA library is introduced and used by the
Sparx5 switch driver.

 ###################
 # Example of use: #
 ###################

- Initialize the rx and tx fdma structs with values for: number of
  DCB's, number of DB's, channel ID, DB size (data buffer size), and
  total size of the requested memory. Also provide two callbacks:
  nextptr_cb() and dataptr_cb() for getting the nextptr and dataptr.

- Allocate memory using fdma_alloc_phys() or fdma_alloc_coherent().

- Initialize the DCB's with fdma_dcb_init().

- Add new DCB's with fdma_dcb_add().

- Free memory with fdma_free_phys() or fdma_free_coherent().

 #####################
 # Patch  breakdown: #
 #####################

Patch #1:  introduces library and selects it for Sparx5.

Patch #2:  includes the fdma_api.h header and removes old symbols.

Patch #3:  replaces old rx and tx variables with equivalent ones from the
           fdma struct. Only the variables that can be changed without
           breaking traffic is changed in this patch.

Patch #4:  uses the library for allocation of rx buffers. This requires
           quite a bit of refactoring in this single patch.

Patch #5:  uses the library for adding DCB's in the rx path.

Patch #6:  uses the library for freeing rx buffers.

Patch #7:  uses the library helpers in the rx path.

Patch #8:  uses the library for allocation of tx buffers. This requires
           quite a bit of refactoring in this single patch.

Patch #9:  uses the library for adding DCB's in the tx path.

Patch #10: uses the library helpers in the tx path.

Patch #11: ditches the existing linked list for storing buffer addresses,
           and instead uses offsets into contiguous memory.

Patch #12: modifies existing rx and tx functions to be direction
           independent.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
matttbe pushed a commit that referenced this issue Sep 5, 2024
If SER L2 occurs during the WoWLAN resume flow, the add interface flow
is triggered by ieee80211_reconfig(). However, due to
rtw89_wow_resume() return failure, it will cause the add interface flow
to be executed again, resulting in a double add list and causing a kernel
panic. Therefore, we have added a check to prevent double adding of the
list.

list_add double add: new=ffff99d6992e2010, prev=ffff99d6992e2010, next=ffff99d695302628.
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:37!
invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
CPU: 0 PID: 9 Comm: kworker/0:1 Tainted: G        W  O       6.6.30-02659-gc18865c4dfbd #1 770df2933251a0e3c888ba69d1053a817a6376a7
Hardware name: HP Grunt/Grunt, BIOS Google_Grunt.11031.169.0 06/24/2021
Workqueue: events_freezable ieee80211_restart_work [mac80211]
RIP: 0010:__list_add_valid_or_report+0x5e/0xb0
Code: c7 74 18 48 39 ce 74 13 b0 01 59 5a 5e 5f 41 58 41 59 41 5a 5d e9 e2 d6 03 00 cc 48 c7 c7 8d 4f 17 83 48 89 c2 e8 02 c0 00 00 <0f> 0b 48 c7 c7 aa 8c 1c 83 e8 f4 bf 00 00 0f 0b 48 c7 c7 c8 bc 12
RSP: 0018:ffffa91b8007bc50 EFLAGS: 00010246
RAX: 0000000000000058 RBX: ffff99d6992e0900 RCX: a014d76c70ef3900
RDX: ffffa91b8007bae8 RSI: 00000000ffffdfff RDI: 0000000000000001
RBP: ffffa91b8007bc88 R08: 0000000000000000 R09: ffffa91b8007bae0
R10: 00000000ffffdfff R11: ffffffff83a79800 R12: ffff99d695302060
R13: ffff99d695300900 R14: ffff99d6992e1be0 R15: ffff99d6992e2010
FS:  0000000000000000(0000) GS:ffff99d6aac00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000078fbdba43480 CR3: 000000010e464000 CR4: 00000000001506f0
Call Trace:
 <TASK>
 ? __die_body+0x1f/0x70
 ? die+0x3d/0x60
 ? do_trap+0xa4/0x110
 ? __list_add_valid_or_report+0x5e/0xb0
 ? do_error_trap+0x6d/0x90
 ? __list_add_valid_or_report+0x5e/0xb0
 ? handle_invalid_op+0x30/0x40
 ? __list_add_valid_or_report+0x5e/0xb0
 ? exc_invalid_op+0x3c/0x50
 ? asm_exc_invalid_op+0x16/0x20
 ? __list_add_valid_or_report+0x5e/0xb0
 rtw89_ops_add_interface+0x309/0x310 [rtw89_core 7c32b1ee6854761c0321027c8a58c5160e41f48f]
 drv_add_interface+0x5c/0x130 [mac80211 83e989e6e616bd5b4b8a2b0a9f9352a2c385a3bc]
 ieee80211_reconfig+0x241/0x13d0 [mac80211 83e989e6e616bd5b4b8a2b0a9f9352a2c385a3bc]
 ? finish_wait+0x3e/0x90
 ? synchronize_rcu_expedited+0x174/0x260
 ? sync_rcu_exp_done_unlocked+0x50/0x50
 ? wake_bit_function+0x40/0x40
 ieee80211_restart_work+0xf0/0x140 [mac80211 83e989e6e616bd5b4b8a2b0a9f9352a2c385a3bc]
 process_scheduled_works+0x1e5/0x480
 worker_thread+0xea/0x1e0
 kthread+0xdb/0x110
 ? move_linked_works+0x90/0x90
 ? kthread_associate_blkcg+0xa0/0xa0
 ret_from_fork+0x3b/0x50
 ? kthread_associate_blkcg+0xa0/0xa0
 ret_from_fork_asm+0x11/0x20
 </TASK>
Modules linked in: dm_integrity async_xor xor async_tx lz4 lz4_compress zstd zstd_compress zram zsmalloc rfcomm cmac uinput algif_hash algif_skcipher af_alg btusb btrtl iio_trig_hrtimer industrialio_sw_trigger btmtk industrialio_configfs btbcm btintel uvcvideo videobuf2_vmalloc iio_trig_sysfs videobuf2_memops videobuf2_v4l2 videobuf2_common uvc snd_hda_codec_hdmi veth snd_hda_intel snd_intel_dspcfg acpi_als snd_hda_codec industrialio_triggered_buffer kfifo_buf snd_hwdep industrialio i2c_piix4 snd_hda_core designware_i2s ip6table_nat snd_soc_max98357a xt_MASQUERADE xt_cgroup snd_soc_acp_rt5682_mach fuse rtw89_8922ae(O) rtw89_8922a(O) rtw89_pci(O) rtw89_core(O) 8021q mac80211(O) bluetooth ecdh_generic ecc cfg80211 r8152 mii joydev
gsmi: Log Shutdown Reason 0x03
---[ end trace 0000000000000000 ]---

Signed-off-by: Chih-Kang Chang <gary.chang@realtek.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Link: https://patch.msgid.link/20240731070506.46100-4-pkshih@realtek.com
matttbe pushed a commit that referenced this issue Sep 5, 2024
The main threat to data consistency in ice_xdp() is a possible asynchronous
PF reset. It can be triggered by a user or by TX timeout handler.

XDP setup and PF reset code access the same resources in the following
sections:
* ice_vsi_close() in ice_prepare_for_reset() - already rtnl-locked
* ice_vsi_rebuild() for the PF VSI - not protected
* ice_vsi_open() - already rtnl-locked

With an unfortunate timing, such accesses can result in a crash such as the
one below:

[ +1.999878] ice 0000:b1:00.0: Registered XDP mem model MEM_TYPE_XSK_BUFF_POOL on Rx ring 14
[ +2.002992] ice 0000:b1:00.0: Registered XDP mem model MEM_TYPE_XSK_BUFF_POOL on Rx ring 18
[Mar15 18:17] ice 0000:b1:00.0 ens801f0np0: NETDEV WATCHDOG: CPU: 38: transmit queue 14 timed out 80692736 ms
[ +0.000093] ice 0000:b1:00.0 ens801f0np0: tx_timeout: VSI_num: 6, Q 14, NTC: 0x0, HW_HEAD: 0x0, NTU: 0x0, INT: 0x4000001
[ +0.000012] ice 0000:b1:00.0 ens801f0np0: tx_timeout recovery level 1, txqueue 14
[ +0.394718] ice 0000:b1:00.0: PTP reset successful
[ +0.006184] BUG: kernel NULL pointer dereference, address: 0000000000000098
[ +0.000045] #PF: supervisor read access in kernel mode
[ +0.000023] #PF: error_code(0x0000) - not-present page
[ +0.000023] PGD 0 P4D 0
[ +0.000018] Oops: 0000 [#1] PREEMPT SMP NOPTI
[ +0.000023] CPU: 38 PID: 7540 Comm: kworker/38:1 Not tainted 6.8.0-rc7 #1
[ +0.000031] Hardware name: Intel Corporation S2600WFT/S2600WFT, BIOS SE5C620.86B.02.01.0014.082620210524 08/26/2021
[ +0.000036] Workqueue: ice ice_service_task [ice]
[ +0.000183] RIP: 0010:ice_clean_tx_ring+0xa/0xd0 [ice]
[...]
[ +0.000013] Call Trace:
[ +0.000016] <TASK>
[ +0.000014] ? __die+0x1f/0x70
[ +0.000029] ? page_fault_oops+0x171/0x4f0
[ +0.000029] ? schedule+0x3b/0xd0
[ +0.000027] ? exc_page_fault+0x7b/0x180
[ +0.000022] ? asm_exc_page_fault+0x22/0x30
[ +0.000031] ? ice_clean_tx_ring+0xa/0xd0 [ice]
[ +0.000194] ice_free_tx_ring+0xe/0x60 [ice]
[ +0.000186] ice_destroy_xdp_rings+0x157/0x310 [ice]
[ +0.000151] ice_vsi_decfg+0x53/0xe0 [ice]
[ +0.000180] ice_vsi_rebuild+0x239/0x540 [ice]
[ +0.000186] ice_vsi_rebuild_by_type+0x76/0x180 [ice]
[ +0.000145] ice_rebuild+0x18c/0x840 [ice]
[ +0.000145] ? delay_tsc+0x4a/0xc0
[ +0.000022] ? delay_tsc+0x92/0xc0
[ +0.000020] ice_do_reset+0x140/0x180 [ice]
[ +0.000886] ice_service_task+0x404/0x1030 [ice]
[ +0.000824] process_one_work+0x171/0x340
[ +0.000685] worker_thread+0x277/0x3a0
[ +0.000675] ? preempt_count_add+0x6a/0xa0
[ +0.000677] ? _raw_spin_lock_irqsave+0x23/0x50
[ +0.000679] ? __pfx_worker_thread+0x10/0x10
[ +0.000653] kthread+0xf0/0x120
[ +0.000635] ? __pfx_kthread+0x10/0x10
[ +0.000616] ret_from_fork+0x2d/0x50
[ +0.000612] ? __pfx_kthread+0x10/0x10
[ +0.000604] ret_from_fork_asm+0x1b/0x30
[ +0.000604] </TASK>

The previous way of handling this through returning -EBUSY is not viable,
particularly when destroying AF_XDP socket, because the kernel proceeds
with removal anyway.

There is plenty of code between those calls and there is no need to create
a large critical section that covers all of them, same as there is no need
to protect ice_vsi_rebuild() with rtnl_lock().

Add xdp_state_lock mutex to protect ice_vsi_rebuild() and ice_xdp().

Leaving unprotected sections in between would result in two states that
have to be considered:
1. when the VSI is closed, but not yet rebuild
2. when VSI is already rebuild, but not yet open

The latter case is actually already handled through !netif_running() case,
we just need to adjust flag checking a little. The former one is not as
trivial, because between ice_vsi_close() and ice_vsi_rebuild(), a lot of
hardware interaction happens, this can make adding/deleting rings exit
with an error. Luckily, VSI rebuild is pending and can apply new
configuration for us in a managed fashion.

Therefore, add an additional VSI state flag ICE_VSI_REBUILD_PENDING to
indicate that ice_xdp() can just hot-swap the program.

Also, as ice_vsi_rebuild() flow is touched in this patch, make it more
consistent by deconfiguring VSI when coalesce allocation fails.

Fixes: 2d4238f ("ice: Add support for AF_XDP")
Fixes: efc2214 ("ice: Add support for XDP")
Reviewed-by: Wojciech Drewek <wojciech.drewek@intel.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Chandan Kumar Rout <chandanx.rout@intel.com>
Signed-off-by: Larysa Zaremba <larysa.zaremba@intel.com>
Reviewed-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
matttbe pushed a commit that referenced this issue Sep 5, 2024
We observed a null-ptr-deref in fou_gro_receive() while shutting down
a host.  [0]

The NULL pointer is sk->sk_user_data, and the offset 8 is of protocol
in struct fou.

When fou_release() is called due to netns dismantle or explicit tunnel
teardown, udp_tunnel_sock_release() sets NULL to sk->sk_user_data.
Then, the tunnel socket is destroyed after a single RCU grace period.

So, in-flight udp4_gro_receive() could find the socket and execute the
FOU GRO handler, where sk->sk_user_data could be NULL.

Let's use rcu_dereference_sk_user_data() in fou_from_sock() and add NULL
checks in FOU GRO handlers.

[0]:
BUG: kernel NULL pointer dereference, address: 0000000000000008
 PF: supervisor read access in kernel mode
 PF: error_code(0x0000) - not-present page
PGD 80000001032f4067 P4D 80000001032f4067 PUD 103240067 PMD 0
SMP PTI
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.10.216-204.855.amzn2.x86_64 #1
Hardware name: Amazon EC2 c5.large/, BIOS 1.0 10/16/2017
RIP: 0010:fou_gro_receive (net/ipv4/fou.c:233) [fou]
Code: 41 5f c3 cc cc cc cc e8 e7 2e 69 f4 0f 1f 80 00 00 00 00 0f 1f 44 00 00 49 89 f8 41 54 48 89 f7 48 89 d6 49 8b 80 88 02 00 00 <0f> b6 48 08 0f b7 42 4a 66 25 fd fd 80 cc 02 66 89 42 4a 0f b6 42
RSP: 0018:ffffa330c0003d08 EFLAGS: 00010297
RAX: 0000000000000000 RBX: ffff93d9e3a6b900 RCX: 0000000000000010
RDX: ffff93d9e3a6b900 RSI: ffff93d9e3a6b900 RDI: ffff93dac2e24d08
RBP: ffff93d9e3a6b900 R08: ffff93dacbce6400 R09: 0000000000000002
R10: 0000000000000000 R11: ffffffffb5f369b0 R12: ffff93dacbce6400
R13: ffff93dac2e24d08 R14: 0000000000000000 R15: ffffffffb4edd1c0
FS:  0000000000000000(0000) GS:ffff93daee800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000008 CR3: 0000000102140001 CR4: 00000000007706f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
 <IRQ>
 ? show_trace_log_lvl (arch/x86/kernel/dumpstack.c:259)
 ? __die_body.cold (arch/x86/kernel/dumpstack.c:478 arch/x86/kernel/dumpstack.c:420)
 ? no_context (arch/x86/mm/fault.c:752)
 ? exc_page_fault (arch/x86/include/asm/irqflags.h:49 arch/x86/include/asm/irqflags.h:89 arch/x86/mm/fault.c:1435 arch/x86/mm/fault.c:1483)
 ? asm_exc_page_fault (arch/x86/include/asm/idtentry.h:571)
 ? fou_gro_receive (net/ipv4/fou.c:233) [fou]
 udp_gro_receive (include/linux/netdevice.h:2552 net/ipv4/udp_offload.c:559)
 udp4_gro_receive (net/ipv4/udp_offload.c:604)
 inet_gro_receive (net/ipv4/af_inet.c:1549 (discriminator 7))
 dev_gro_receive (net/core/dev.c:6035 (discriminator 4))
 napi_gro_receive (net/core/dev.c:6170)
 ena_clean_rx_irq (drivers/amazon/net/ena/ena_netdev.c:1558) [ena]
 ena_io_poll (drivers/amazon/net/ena/ena_netdev.c:1742) [ena]
 napi_poll (net/core/dev.c:6847)
 net_rx_action (net/core/dev.c:6917)
 __do_softirq (arch/x86/include/asm/jump_label.h:25 include/linux/jump_label.h:200 include/trace/events/irq.h:142 kernel/softirq.c:299)
 asm_call_irq_on_stack (arch/x86/entry/entry_64.S:809)
</IRQ>
 do_softirq_own_stack (arch/x86/include/asm/irq_stack.h:27 arch/x86/include/asm/irq_stack.h:77 arch/x86/kernel/irq_64.c:77)
 irq_exit_rcu (kernel/softirq.c:393 kernel/softirq.c:423 kernel/softirq.c:435)
 common_interrupt (arch/x86/kernel/irq.c:239)
 asm_common_interrupt (arch/x86/include/asm/idtentry.h:626)
RIP: 0010:acpi_idle_do_entry (arch/x86/include/asm/irqflags.h:49 arch/x86/include/asm/irqflags.h:89 drivers/acpi/processor_idle.c:114 drivers/acpi/processor_idle.c:575)
Code: 8b 15 d1 3c c4 02 ed c3 cc cc cc cc 65 48 8b 04 25 40 ef 01 00 48 8b 00 a8 08 75 eb 0f 1f 44 00 00 0f 00 2d d5 09 55 00 fb f4 <fa> c3 cc cc cc cc e9 be fc ff ff 66 66 2e 0f 1f 84 00 00 00 00 00
RSP: 0018:ffffffffb5603e58 EFLAGS: 00000246
RAX: 0000000000004000 RBX: ffff93dac0929c00 RCX: ffff93daee833900
RDX: ffff93daee800000 RSI: ffff93daee87dc00 RDI: ffff93daee87dc64
RBP: 0000000000000001 R08: ffffffffb5e7b6c0 R09: 0000000000000044
R10: ffff93daee831b04 R11: 00000000000001cd R12: 0000000000000001
R13: ffffffffb5e7b740 R14: 0000000000000001 R15: 0000000000000000
 ? sched_clock_cpu (kernel/sched/clock.c:371)
 acpi_idle_enter (drivers/acpi/processor_idle.c:712 (discriminator 3))
 cpuidle_enter_state (drivers/cpuidle/cpuidle.c:237)
 cpuidle_enter (drivers/cpuidle/cpuidle.c:353)
 cpuidle_idle_call (kernel/sched/idle.c:158 kernel/sched/idle.c:239)
 do_idle (kernel/sched/idle.c:302)
 cpu_startup_entry (kernel/sched/idle.c:395 (discriminator 1))
 start_kernel (init/main.c:1048)
 secondary_startup_64_no_verify (arch/x86/kernel/head_64.S:310)
Modules linked in: udp_diag tcp_diag inet_diag nft_nat ipip tunnel4 dummy fou ip_tunnel nft_masq nft_chain_nat nf_nat wireguard nft_ct curve25519_x86_64 libcurve25519_generic nf_conntrack libchacha20poly1305 nf_defrag_ipv6 nf_defrag_ipv4 nft_objref chacha_x86_64 nft_counter nf_tables nfnetlink poly1305_x86_64 ip6_udp_tunnel udp_tunnel libchacha crc32_pclmul ghash_clmulni_intel aesni_intel crypto_simd cryptd glue_helper mousedev psmouse button ena ptp pps_core crc32c_intel
CR2: 0000000000000008

Fixes: d92283e ("fou: change to use UDP socket GRO")
Reported-by: Alphonse Kurian <alkurian@amazon.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20240902173927.62706-1-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
matttbe pushed a commit that referenced this issue Sep 6, 2024
Steve French reported null pointer dereference error from sha256 lib.
cifs.ko can send session setup requests on reused connection.
If reused connection is used for binding session, conn->binding can
still remain true and generate_preauth_hash() will not set
sess->Preauth_HashValue and it will be NULL.
It is used as a material to create an encryption key in
ksmbd_gen_smb311_encryptionkey. ->Preauth_HashValue cause null pointer
dereference error from crypto_shash_update().

BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP PTI
CPU: 8 PID: 429254 Comm: kworker/8:39
Hardware name: LENOVO 20MAS08500/20MAS08500, BIOS N2CET69W (1.52 )
Workqueue: ksmbd-io handle_ksmbd_work [ksmbd]
RIP: 0010:lib_sha256_base_do_update.isra.0+0x11e/0x1d0 [sha256_ssse3]
<TASK>
? show_regs+0x6d/0x80
? __die+0x24/0x80
? page_fault_oops+0x99/0x1b0
? do_user_addr_fault+0x2ee/0x6b0
? exc_page_fault+0x83/0x1b0
? asm_exc_page_fault+0x27/0x30
? __pfx_sha256_transform_rorx+0x10/0x10 [sha256_ssse3]
? lib_sha256_base_do_update.isra.0+0x11e/0x1d0 [sha256_ssse3]
? __pfx_sha256_transform_rorx+0x10/0x10 [sha256_ssse3]
? __pfx_sha256_transform_rorx+0x10/0x10 [sha256_ssse3]
_sha256_update+0x77/0xa0 [sha256_ssse3]
sha256_avx2_update+0x15/0x30 [sha256_ssse3]
crypto_shash_update+0x1e/0x40
hmac_update+0x12/0x20
crypto_shash_update+0x1e/0x40
generate_key+0x234/0x380 [ksmbd]
generate_smb3encryptionkey+0x40/0x1c0 [ksmbd]
ksmbd_gen_smb311_encryptionkey+0x72/0xa0 [ksmbd]
ntlm_authenticate.isra.0+0x423/0x5d0 [ksmbd]
smb2_sess_setup+0x952/0xaa0 [ksmbd]
__process_request+0xa3/0x1d0 [ksmbd]
__handle_ksmbd_work+0x1c4/0x2f0 [ksmbd]
handle_ksmbd_work+0x2d/0xa0 [ksmbd]
process_one_work+0x16c/0x350
worker_thread+0x306/0x440
? __pfx_worker_thread+0x10/0x10
kthread+0xef/0x120
? __pfx_kthread+0x10/0x10
ret_from_fork+0x44/0x70
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1b/0x30
</TASK>

Fixes: f5a544e ("ksmbd: add support for SMB3 multichannel")
Cc: stable@vger.kernel.org # v5.15+
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
matttbe pushed a commit that referenced this issue Sep 6, 2024
The fscache_cookie_lru_timer is initialized when the fscache module
is inserted, but is not deleted when the fscache module is removed.
If timer_reduce() is called before removing the fscache module,
the fscache_cookie_lru_timer will be added to the timer list of
the current cpu. Afterwards, a use-after-free will be triggered
in the softIRQ after removing the fscache module, as follows:

==================================================================
BUG: unable to handle page fault for address: fffffbfff803c9e9
 PF: supervisor read access in kernel mode
 PF: error_code(0x0000) - not-present page
PGD 21ffea067 P4D 21ffea067 PUD 21ffe6067 PMD 110a7c067 PTE 0
Oops: Oops: 0000 [#1] PREEMPT SMP KASAN PTI
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Tainted: G W 6.11.0-rc3 #855
Tainted: [W]=WARN
RIP: 0010:__run_timer_base.part.0+0x254/0x8a0
Call Trace:
 <IRQ>
 tmigr_handle_remote_up+0x627/0x810
 __walk_groups.isra.0+0x47/0x140
 tmigr_handle_remote+0x1fa/0x2f0
 handle_softirqs+0x180/0x590
 irq_exit_rcu+0x84/0xb0
 sysvec_apic_timer_interrupt+0x6e/0x90
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:default_idle+0xf/0x20
 default_idle_call+0x38/0x60
 do_idle+0x2b5/0x300
 cpu_startup_entry+0x54/0x60
 start_secondary+0x20d/0x280
 common_startup_64+0x13e/0x148
 </TASK>
Modules linked in: [last unloaded: netfs]
==================================================================

Therefore delete fscache_cookie_lru_timer when removing the fscahe module.

Fixes: 12bb21a ("fscache: Implement cookie user counting and resource pinning")
Cc: stable@kernel.org
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Link: https://lore.kernel.org/r/20240826112056.2458299-1-libaokun@huaweicloud.com
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
matttbe pushed a commit that referenced this issue Sep 6, 2024
Commit 8c61291 ("mm: fix incorrect vbq reference in
purge_fragmented_block") extended the 'vmap_block' structure to contain a
'cpu' field which is set at allocation time to the id of the initialising
CPU.

When a new 'vmap_block' is being instantiated by new_vmap_block(), the
partially initialised structure is added to the local 'vmap_block_queue'
xarray before the 'cpu' field has been initialised.  If another CPU is
concurrently walking the xarray (e.g.  via vm_unmap_aliases()), then it
may perform an out-of-bounds access to the remote queue thanks to an
uninitialised index.

This has been observed as UBSAN errors in Android:

 | Internal error: UBSAN: array index out of bounds: 00000000f2005512 [#1] PREEMPT SMP
 |
 | Call trace:
 |  purge_fragmented_block+0x204/0x21c
 |  _vm_unmap_aliases+0x170/0x378
 |  vm_unmap_aliases+0x1c/0x28
 |  change_memory_common+0x1dc/0x26c
 |  set_memory_ro+0x18/0x24
 |  module_enable_ro+0x98/0x238
 |  do_init_module+0x1b0/0x310

Move the initialisation of 'vb->cpu' in new_vmap_block() ahead of the
addition to the xarray.

Link: https://lkml.kernel.org/r/20240812171606.17486-1-will@kernel.org
Fixes: 8c61291 ("mm: fix incorrect vbq reference in purge_fragmented_block")
Signed-off-by: Will Deacon <will@kernel.org>
Reviewed-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Zhaoyang Huang <zhaoyang.huang@unisoc.com>
Cc: Hailong.Liu <hailong.liu@oppo.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
matttbe pushed a commit that referenced this issue Sep 6, 2024
When enable CONFIG_MEMCG & CONFIG_KFENCE & CONFIG_KMEMLEAK, the following
warning always occurs,This is because the following call stack occurred:
mem_pool_alloc
    kmem_cache_alloc_noprof
        slab_alloc_node
            kfence_alloc

Once the kfence allocation is successful,slab->obj_exts will not be empty,
because it has already been assigned a value in kfence_init_pool.

Since in the prepare_slab_obj_exts_hook function,we perform a check for
s->flags & (SLAB_NO_OBJ_EXT | SLAB_NOLEAKTRACE),the alloc_tag_add function
will not be called as a result.Therefore,ref->ct remains NULL.

However,when we call mem_pool_free,since obj_ext is not empty, it
eventually leads to the alloc_tag_sub scenario being invoked.  This is
where the warning occurs.

So we should add corresponding checks in the alloc_tagging_slab_free_hook.
For __GFP_NO_OBJ_EXT case,I didn't see the specific case where it's using
kfence,so I won't add the corresponding check in
alloc_tagging_slab_free_hook for now.

[    3.734349] ------------[ cut here ]------------
[    3.734807] alloc_tag was not set
[    3.735129] WARNING: CPU: 4 PID: 40 at ./include/linux/alloc_tag.h:130 kmem_cache_free+0x444/0x574
[    3.735866] Modules linked in: autofs4
[    3.736211] CPU: 4 UID: 0 PID: 40 Comm: ksoftirqd/4 Tainted: G        W          6.11.0-rc3-dirty #1
[    3.736969] Tainted: [W]=WARN
[    3.737258] Hardware name: QEMU KVM Virtual Machine, BIOS unknown 2/2/2022
[    3.737875] pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[    3.738501] pc : kmem_cache_free+0x444/0x574
[    3.738951] lr : kmem_cache_free+0x444/0x574
[    3.739361] sp : ffff80008357bb60
[    3.739693] x29: ffff80008357bb70 x28: 0000000000000000 x27: 0000000000000000
[    3.740338] x26: ffff80008207f000 x25: ffff000b2eb2fd60 x24: ffff0000c0005700
[    3.740982] x23: ffff8000804229e4 x22: ffff800082080000 x21: ffff800081756000
[    3.741630] x20: fffffd7ff8253360 x19: 00000000000000a8 x18: ffffffffffffffff
[    3.742274] x17: ffff800ab327f000 x16: ffff800083398000 x15: ffff800081756df0
[    3.742919] x14: 0000000000000000 x13: 205d344320202020 x12: 5b5d373038343337
[    3.743560] x11: ffff80008357b650 x10: 000000000000005d x9 : 00000000ffffffd0
[    3.744231] x8 : 7f7f7f7f7f7f7f7f x7 : ffff80008237bad0 x6 : c0000000ffff7fff
[    3.744907] x5 : ffff80008237ba78 x4 : ffff8000820bbad0 x3 : 0000000000000001
[    3.745580] x2 : 68d66547c09f7800 x1 : 68d66547c09f7800 x0 : 0000000000000000
[    3.746255] Call trace:
[    3.746530]  kmem_cache_free+0x444/0x574
[    3.746931]  mem_pool_free+0x44/0xf4
[    3.747306]  free_object_rcu+0xc8/0xdc
[    3.747693]  rcu_do_batch+0x234/0x8a4
[    3.748075]  rcu_core+0x230/0x3e4
[    3.748424]  rcu_core_si+0x14/0x1c
[    3.748780]  handle_softirqs+0x134/0x378
[    3.749189]  run_ksoftirqd+0x70/0x9c
[    3.749560]  smpboot_thread_fn+0x148/0x22c
[    3.749978]  kthread+0x10c/0x118
[    3.750323]  ret_from_fork+0x10/0x20
[    3.750696] ---[ end trace 0000000000000000 ]---

Link: https://lkml.kernel.org/r/20240816013336.17505-1-hao.ge@linux.dev
Fixes: 4b87369 ("mm/slab: add allocation accounting into slab allocation and free paths")
Signed-off-by: Hao Ge <gehao@kylinos.cn>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Kees Cook <kees@kernel.org>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
matttbe pushed a commit that referenced this issue Sep 6, 2024
If we have 2 threads that are using the same file descriptor and one of
them is doing direct IO writes while the other is doing fsync, we have a
race where we can end up either:

1) Attempt a fsync without holding the inode's lock, triggering an
   assertion failures when assertions are enabled;

2) Do an invalid memory access from the fsync task because the file private
   points to memory allocated on stack by the direct IO task and it may be
   used by the fsync task after the stack was destroyed.

The race happens like this:

1) A user space program opens a file descriptor with O_DIRECT;

2) The program spawns 2 threads using libpthread for example;

3) One of the threads uses the file descriptor to do direct IO writes,
   while the other calls fsync using the same file descriptor.

4) Call task A the thread doing direct IO writes and task B the thread
   doing fsyncs;

5) Task A does a direct IO write, and at btrfs_direct_write() sets the
   file's private to an on stack allocated private with the member
   'fsync_skip_inode_lock' set to true;

6) Task B enters btrfs_sync_file() and sees that there's a private
   structure associated to the file which has 'fsync_skip_inode_lock' set
   to true, so it skips locking the inode's VFS lock;

7) Task A completes the direct IO write, and resets the file's private to
   NULL since it had no prior private and our private was stack allocated.
   Then it unlocks the inode's VFS lock;

8) Task B enters btrfs_get_ordered_extents_for_logging(), then the
   assertion that checks the inode's VFS lock is held fails, since task B
   never locked it and task A has already unlocked it.

The stack trace produced is the following:

   assertion failed: inode_is_locked(&inode->vfs_inode), in fs/btrfs/ordered-data.c:983
   ------------[ cut here ]------------
   kernel BUG at fs/btrfs/ordered-data.c:983!
   Oops: invalid opcode: 0000 [#1] PREEMPT SMP PTI
   CPU: 9 PID: 5072 Comm: worker Tainted: G     U     OE      6.10.5-1-default #1 openSUSE Tumbleweed 69f48d427608e1c09e60ea24c6c55e2ca1b049e8
   Hardware name: Acer Predator PH315-52/Covini_CFS, BIOS V1.12 07/28/2020
   RIP: 0010:btrfs_get_ordered_extents_for_logging.cold+0x1f/0x42 [btrfs]
   Code: 50 d6 86 c0 e8 (...)
   RSP: 0018:ffff9e4a03dcfc78 EFLAGS: 00010246
   RAX: 0000000000000054 RBX: ffff9078a9868e98 RCX: 0000000000000000
   RDX: 0000000000000000 RSI: ffff907dce4a7800 RDI: ffff907dce4a7800
   RBP: ffff907805518800 R08: 0000000000000000 R09: ffff9e4a03dcfb38
   R10: ffff9e4a03dcfb30 R11: 0000000000000003 R12: ffff907684ae7800
   R13: 0000000000000001 R14: ffff90774646b600 R15: 0000000000000000
   FS:  00007f04b96006c0(0000) GS:ffff907dce480000(0000) knlGS:0000000000000000
   CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
   CR2: 00007f32acbfc000 CR3: 00000001fd4fa005 CR4: 00000000003726f0
   Call Trace:
    <TASK>
    ? __die_body.cold+0x14/0x24
    ? die+0x2e/0x50
    ? do_trap+0xca/0x110
    ? do_error_trap+0x6a/0x90
    ? btrfs_get_ordered_extents_for_logging.cold+0x1f/0x42 [btrfs bb26272d49b4cdc847cf3f7faadd459b62caee9a]
    ? exc_invalid_op+0x50/0x70
    ? btrfs_get_ordered_extents_for_logging.cold+0x1f/0x42 [btrfs bb26272d49b4cdc847cf3f7faadd459b62caee9a]
    ? asm_exc_invalid_op+0x1a/0x20
    ? btrfs_get_ordered_extents_for_logging.cold+0x1f/0x42 [btrfs bb26272d49b4cdc847cf3f7faadd459b62caee9a]
    ? btrfs_get_ordered_extents_for_logging.cold+0x1f/0x42 [btrfs bb26272d49b4cdc847cf3f7faadd459b62caee9a]
    btrfs_sync_file+0x21a/0x4d0 [btrfs bb26272d49b4cdc847cf3f7faadd459b62caee9a]
    ? __seccomp_filter+0x31d/0x4f0
    __x64_sys_fdatasync+0x4f/0x90
    do_syscall_64+0x82/0x160
    ? do_futex+0xcb/0x190
    ? __x64_sys_futex+0x10e/0x1d0
    ? switch_fpu_return+0x4f/0xd0
    ? syscall_exit_to_user_mode+0x72/0x220
    ? do_syscall_64+0x8e/0x160
    ? syscall_exit_to_user_mode+0x72/0x220
    ? do_syscall_64+0x8e/0x160
    ? syscall_exit_to_user_mode+0x72/0x220
    ? do_syscall_64+0x8e/0x160
    ? syscall_exit_to_user_mode+0x72/0x220
    ? do_syscall_64+0x8e/0x160
    entry_SYSCALL_64_after_hwframe+0x76/0x7e

Another problem here is if task B grabs the private pointer and then uses
it after task A has finished, since the private was allocated in the stack
of task A, it results in some invalid memory access with a hard to predict
result.

This issue, triggering the assertion, was observed with QEMU workloads by
two users in the Link tags below.

Fix this by not relying on a file's private to pass information to fsync
that it should skip locking the inode and instead pass this information
through a special value stored in current->journal_info. This is safe
because in the relevant section of the direct IO write path we are not
holding a transaction handle, so current->journal_info is NULL.

The following C program triggers the issue:

   $ cat repro.c
   /* Get the O_DIRECT definition. */
   #ifndef _GNU_SOURCE
   #define _GNU_SOURCE
   #endif

   #include <stdio.h>
   #include <stdlib.h>
   #include <unistd.h>
   #include <stdint.h>
   #include <fcntl.h>
   #include <errno.h>
   #include <string.h>
   #include <pthread.h>

   static int fd;

   static ssize_t do_write(int fd, const void *buf, size_t count, off_t offset)
   {
       while (count > 0) {
           ssize_t ret;

           ret = pwrite(fd, buf, count, offset);
           if (ret < 0) {
               if (errno == EINTR)
                   continue;
               return ret;
           }
           count -= ret;
           buf += ret;
       }
       return 0;
   }

   static void *fsync_loop(void *arg)
   {
       while (1) {
           int ret;

           ret = fsync(fd);
           if (ret != 0) {
               perror("Fsync failed");
               exit(6);
           }
       }
   }

   int main(int argc, char *argv[])
   {
       long pagesize;
       void *write_buf;
       pthread_t fsyncer;
       int ret;

       if (argc != 2) {
           fprintf(stderr, "Use: %s <file path>\n", argv[0]);
           return 1;
       }

       fd = open(argv[1], O_WRONLY | O_CREAT | O_TRUNC | O_DIRECT, 0666);
       if (fd == -1) {
           perror("Failed to open/create file");
           return 1;
       }

       pagesize = sysconf(_SC_PAGE_SIZE);
       if (pagesize == -1) {
           perror("Failed to get page size");
           return 2;
       }

       ret = posix_memalign(&write_buf, pagesize, pagesize);
       if (ret) {
           perror("Failed to allocate buffer");
           return 3;
       }

       ret = pthread_create(&fsyncer, NULL, fsync_loop, NULL);
       if (ret != 0) {
           fprintf(stderr, "Failed to create writer thread: %d\n", ret);
           return 4;
       }

       while (1) {
           ret = do_write(fd, write_buf, pagesize, 0);
           if (ret != 0) {
               perror("Write failed");
               exit(5);
           }
       }

       return 0;
   }

   $ mkfs.btrfs -f /dev/sdi
   $ mount /dev/sdi /mnt/sdi
   $ timeout 10 ./repro /mnt/sdi/foo

Usually the race is triggered within less than 1 second. A test case for
fstests will follow soon.

Reported-by: Paulo Dias <paulo.miguel.dias@gmail.com>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=219187
Reported-by: Andreas Jahn <jahn-andi@web.de>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=219199
Reported-by: syzbot+4704b3cc972bd76024f1@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-btrfs/00000000000044ff540620d7dee2@google.com/
Fixes: 939b656 ("btrfs: fix corruption after buffer fault in during direct IO append write")
CC: stable@vger.kernel.org # 5.15+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
matttbe pushed a commit that referenced this issue Sep 6, 2024
Chi Zhiling reported:

  We found a null pointer accessing in tracefs[1], the reason is that the
  variable 'ei_child' is set to LIST_POISON1, that means the list was
  removed in eventfs_remove_rec. so when access the ei_child->is_freed, the
  panic triggered.

  by the way, the following script can reproduce this panic

  loop1 (){
      while true
      do
          echo "p:kp submit_bio" > /sys/kernel/debug/tracing/kprobe_events
          echo "" > /sys/kernel/debug/tracing/kprobe_events
      done
  }
  loop2 (){
      while true
      do
          tree /sys/kernel/debug/tracing/events/kprobes/
      done
  }
  loop1 &
  loop2

  [1]:
  [ 1147.959632][T17331] Unable to handle kernel paging request at virtual address dead000000000150
  [ 1147.968239][T17331] Mem abort info:
  [ 1147.971739][T17331]   ESR = 0x0000000096000004
  [ 1147.976172][T17331]   EC = 0x25: DABT (current EL), IL = 32 bits
  [ 1147.982171][T17331]   SET = 0, FnV = 0
  [ 1147.985906][T17331]   EA = 0, S1PTW = 0
  [ 1147.989734][T17331]   FSC = 0x04: level 0 translation fault
  [ 1147.995292][T17331] Data abort info:
  [ 1147.998858][T17331]   ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000
  [ 1148.005023][T17331]   CM = 0, WnR = 0, TnD = 0, TagAccess = 0
  [ 1148.010759][T17331]   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
  [ 1148.016752][T17331] [dead000000000150] address between user and kernel address ranges
  [ 1148.024571][T17331] Internal error: Oops: 0000000096000004 [#1] SMP
  [ 1148.030825][T17331] Modules linked in: team_mode_loadbalance team nlmon act_gact cls_flower sch_ingress bonding tls macvlan dummy ib_core bridge stp llc veth amdgpu amdxcp mfd_core gpu_sched drm_exec drm_buddy radeon crct10dif_ce video drm_suballoc_helper ghash_ce drm_ttm_helper sha2_ce ttm sha256_arm64 i2c_algo_bit sha1_ce sbsa_gwdt cp210x drm_display_helper cec sr_mod cdrom drm_kms_helper binfmt_misc sg loop fuse drm dm_mod nfnetlink ip_tables autofs4 [last unloaded: tls]
  [ 1148.072808][T17331] CPU: 3 PID: 17331 Comm: ls Tainted: G        W         ------- ----  6.6.43 #2
  [ 1148.081751][T17331] Source Version: 21b3b386e948bedd29369af66f3e98ab01b1c650
  [ 1148.088783][T17331] Hardware name: Greatwall GW-001M1A-FTF/GW-001M1A-FTF, BIOS KunLun BIOS V4.0 07/16/2020
  [ 1148.098419][T17331] pstate: 20000005 (nzCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
  [ 1148.106060][T17331] pc : eventfs_iterate+0x2c0/0x398
  [ 1148.111017][T17331] lr : eventfs_iterate+0x2fc/0x398
  [ 1148.115969][T17331] sp : ffff80008d56bbd0
  [ 1148.119964][T17331] x29: ffff80008d56bbf0 x28: ffff001ff5be2600 x27: 0000000000000000
  [ 1148.127781][T17331] x26: ffff001ff52ca4e0 x25: 0000000000009977 x24: dead000000000100
  [ 1148.135598][T17331] x23: 0000000000000000 x22: 000000000000000b x21: ffff800082645f10
  [ 1148.143415][T17331] x20: ffff001fddf87c70 x19: ffff80008d56bc90 x18: 0000000000000000
  [ 1148.151231][T17331] x17: 0000000000000000 x16: 0000000000000000 x15: ffff001ff52ca4e0
  [ 1148.159048][T17331] x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000
  [ 1148.166864][T17331] x11: 0000000000000000 x10: 0000000000000000 x9 : ffff8000804391d0
  [ 1148.174680][T17331] x8 : 0000000180000000 x7 : 0000000000000018 x6 : 0000aaab04b92862
  [ 1148.182498][T17331] x5 : 0000aaab04b92862 x4 : 0000000080000000 x3 : 0000000000000068
  [ 1148.190314][T17331] x2 : 000000000000000f x1 : 0000000000007ea8 x0 : 0000000000000001
  [ 1148.198131][T17331] Call trace:
  [ 1148.201259][T17331]  eventfs_iterate+0x2c0/0x398
  [ 1148.205864][T17331]  iterate_dir+0x98/0x188
  [ 1148.210036][T17331]  __arm64_sys_getdents64+0x78/0x160
  [ 1148.215161][T17331]  invoke_syscall+0x78/0x108
  [ 1148.219593][T17331]  el0_svc_common.constprop.0+0x48/0xf0
  [ 1148.224977][T17331]  do_el0_svc+0x24/0x38
  [ 1148.228974][T17331]  el0_svc+0x40/0x168
  [ 1148.232798][T17331]  el0t_64_sync_handler+0x120/0x130
  [ 1148.237836][T17331]  el0t_64_sync+0x1a4/0x1a8
  [ 1148.242182][T17331] Code: 54ffff6c f9400676 910006d6 f9000676 (b9405300)
  [ 1148.248955][T17331] ---[ end trace 0000000000000000 ]---

The issue is that list_del() is used on an SRCU protected list variable
before the synchronization occurs. This can poison the list pointers while
there is a reader iterating the list.

This is simply fixed by using list_del_rcu() that is specifically made for
this purpose.

Link: https://lore.kernel.org/linux-trace-kernel/20240829085025.3600021-1-chizhiling@163.com/

Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20240904131605.640d42b1@gandalf.local.home
Fixes: 43aa6f9 ("eventfs: Get rid of dentry pointers without refcounts")
Reported-by: Chi Zhiling <chizhiling@kylinos.cn>
Tested-by: Chi Zhiling <chizhiling@kylinos.cn>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
matttbe pushed a commit that referenced this issue Sep 6, 2024
The start_kthread() and stop_thread() code was not always called with the
interface_lock held. This means that the kthread variable could be
unexpectedly changed causing the kthread_stop() to be called on it when it
should not have been, leading to:

 while true; do
   rtla timerlat top -u -q & PID=$!;
   sleep 5;
   kill -INT $PID;
   sleep 0.001;
   kill -TERM $PID;
   wait $PID;
  done

Causing the following OOPS:

 Oops: general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] PREEMPT SMP KASAN PTI
 KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017]
 CPU: 5 UID: 0 PID: 885 Comm: timerlatu/5 Not tainted 6.11.0-rc4-test-00002-gbc754cc76d1b-dirty #125 a533010b71dab205ad2f507188ce8c82203b0254
 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
 RIP: 0010:hrtimer_active+0x58/0x300
 Code: 48 c1 ee 03 41 54 48 01 d1 48 01 d6 55 53 48 83 ec 20 80 39 00 0f 85 30 02 00 00 49 8b 6f 30 4c 8d 75 10 4c 89 f0 48 c1 e8 03 <0f> b6 3c 10 4c 89 f0 83 e0 07 83 c0 03 40 38 f8 7c 09 40 84 ff 0f
 RSP: 0018:ffff88811d97f940 EFLAGS: 00010202
 RAX: 0000000000000002 RBX: ffff88823c6b5b28 RCX: ffffed10478d6b6b
 RDX: dffffc0000000000 RSI: ffffed10478d6b6c RDI: ffff88823c6b5b28
 RBP: 0000000000000000 R08: ffff88823c6b5b58 R09: ffff88823c6b5b60
 R10: ffff88811d97f957 R11: 0000000000000010 R12: 00000000000a801d
 R13: ffff88810d8b35d8 R14: 0000000000000010 R15: ffff88823c6b5b28
 FS:  0000000000000000(0000) GS:ffff88823c680000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000561858ad7258 CR3: 000000007729e001 CR4: 0000000000170ef0
 Call Trace:
  <TASK>
  ? die_addr+0x40/0xa0
  ? exc_general_protection+0x154/0x230
  ? asm_exc_general_protection+0x26/0x30
  ? hrtimer_active+0x58/0x300
  ? __pfx_mutex_lock+0x10/0x10
  ? __pfx_locks_remove_file+0x10/0x10
  hrtimer_cancel+0x15/0x40
  timerlat_fd_release+0x8e/0x1f0
  ? security_file_release+0x43/0x80
  __fput+0x372/0xb10
  task_work_run+0x11e/0x1f0
  ? _raw_spin_lock+0x85/0xe0
  ? __pfx_task_work_run+0x10/0x10
  ? poison_slab_object+0x109/0x170
  ? do_exit+0x7a0/0x24b0
  do_exit+0x7bd/0x24b0
  ? __pfx_migrate_enable+0x10/0x10
  ? __pfx_do_exit+0x10/0x10
  ? __pfx_read_tsc+0x10/0x10
  ? ktime_get+0x64/0x140
  ? _raw_spin_lock_irq+0x86/0xe0
  do_group_exit+0xb0/0x220
  get_signal+0x17ba/0x1b50
  ? vfs_read+0x179/0xa40
  ? timerlat_fd_read+0x30b/0x9d0
  ? __pfx_get_signal+0x10/0x10
  ? __pfx_timerlat_fd_read+0x10/0x10
  arch_do_signal_or_restart+0x8c/0x570
  ? __pfx_arch_do_signal_or_restart+0x10/0x10
  ? vfs_read+0x179/0xa40
  ? ksys_read+0xfe/0x1d0
  ? __pfx_ksys_read+0x10/0x10
  syscall_exit_to_user_mode+0xbc/0x130
  do_syscall_64+0x74/0x110
  ? __pfx___rseq_handle_notify_resume+0x10/0x10
  ? __pfx_ksys_read+0x10/0x10
  ? fpregs_restore_userregs+0xdb/0x1e0
  ? fpregs_restore_userregs+0xdb/0x1e0
  ? syscall_exit_to_user_mode+0x116/0x130
  ? do_syscall_64+0x74/0x110
  ? do_syscall_64+0x74/0x110
  ? do_syscall_64+0x74/0x110
  entry_SYSCALL_64_after_hwframe+0x71/0x79
 RIP: 0033:0x7ff0070eca9c
 Code: Unable to access opcode bytes at 0x7ff0070eca72.
 RSP: 002b:00007ff006dff8c0 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
 RAX: 0000000000000000 RBX: 0000000000000005 RCX: 00007ff0070eca9c
 RDX: 0000000000000400 RSI: 00007ff006dff9a0 RDI: 0000000000000003
 RBP: 00007ff006dffde0 R08: 0000000000000000 R09: 00007ff000000ba0
 R10: 00007ff007004b08 R11: 0000000000000246 R12: 0000000000000003
 R13: 00007ff006dff9a0 R14: 0000000000000007 R15: 0000000000000008
  </TASK>
 Modules linked in: snd_hda_intel snd_intel_dspcfg snd_intel_sdw_acpi snd_hda_codec snd_hwdep snd_hda_core
 ---[ end trace 0000000000000000 ]---

This is because it would mistakenly call kthread_stop() on a user space
thread making it "exit" before it actually exits.

Since kthreads are created based on global behavior, use a cpumask to know
when kthreads are running and that they need to be shutdown before
proceeding to do new work.

Link: https://lore.kernel.org/all/20240820130001.124768-1-tglozar@redhat.com/

This was debugged by using the persistent ring buffer:

Link: https://lore.kernel.org/all/20240823013902.135036960@goodmis.org/

Note, locking was originally used to fix this, but that proved to cause too
many deadlocks to work around:

  https://lore.kernel.org/linux-trace-kernel/20240823102816.5e55753b@gandalf.local.home/

Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: "Luis Claudio R. Goncalves" <lgoncalv@redhat.com>
Link: https://lore.kernel.org/20240904103428.08efdf4c@gandalf.local.home
Fixes: e88ed22 ("tracing/timerlat: Add user-space interface")
Reported-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
matttbe pushed a commit that referenced this issue Sep 9, 2024
…rnel/git/netfilter/nf-next

Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

The following patchset contains Netfilter updates for net-next:

Patch #1 adds ctnetlink support for kernel side filtering for
	 deletions, from Changliang Wu.

Patch #2 updates nft_counter support to Use u64_stats_t,
	 from Sebastian Andrzej Siewior.

Patch #3 uses kmemdup_array() in all xtables frontends,
	 from Yan Zhen.

Patch #4 is a oneliner to use ERR_CAST() in nf_conntrack instead
	 opencoded casting, from Shen Lichuan.

Patch #5 removes unused argument in nftables .validate interface,
	 from Florian Westphal.

Patch #6 is a oneliner to correct a typo in nftables kdoc,
	 from Simon Horman.

Patch #7 fixes missing kdoc in nftables, also from Simon.

Patch #8 updates nftables to handle timeout less than CONFIG_HZ.

Patch #9 rejects element expiration if timeout is zero,
	 otherwise it is silently ignored.

Patch #10 disallows element expiration larger than timeout.

Patch #11 removes unnecessary READ_ONCE annotation while mutex is held.

Patch #12 adds missing READ_ONCE/WRITE_ONCE annotation in dynset.

Patch #13 annotates data-races around element expiration.

Patch #14 allocates timeout and expiration in one single set element
	  extension, they are tighly couple, no reason to keep them
	  separated anymore.

Patch #15 updates nftables to interpret zero timeout element as never
	  times out. Note that it is already possible to declare sets
	  with elements that never time out but this generalizes to all
	  kind of set with timeouts.

Patch #16 supports for element timeout and expiration updates.

* tag 'nf-next-24-09-06' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next:
  netfilter: nf_tables: set element timeout update support
  netfilter: nf_tables: zero timeout means element never times out
  netfilter: nf_tables: consolidate timeout extension for elements
  netfilter: nf_tables: annotate data-races around element expiration
  netfilter: nft_dynset: annotate data-races around set timeout
  netfilter: nf_tables: remove annotation to access set timeout while holding lock
  netfilter: nf_tables: reject expiration higher than timeout
  netfilter: nf_tables: reject element expiration with no timeout
  netfilter: nf_tables: elements with timeout below CONFIG_HZ never expire
  netfilter: nf_tables: Add missing Kernel doc
  netfilter: nf_tables: Correct spelling in nf_tables.h
  netfilter: nf_tables: drop unused 3rd argument from validate callback ops
  netfilter: conntrack: Convert to use ERR_CAST()
  netfilter: Use kmemdup_array instead of kmemdup for multiple allocation
  netfilter: nft_counter: Use u64_stats_t for statistic.
  netfilter: ctnetlink: support CTA_FILTER for flush
====================

Link: https://patch.msgid.link/20240905232920.5481-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
matttbe pushed a commit that referenced this issue Sep 11, 2024
Daniel Machon says:

====================
net: lan966x: use the newly introduced FDMA library

This patch series is the second of a 2-part series [1], that adds a new
common FDMA library for Microchip switch chips Sparx5 and lan966x. These
chips share the same FDMA engine, and as such will benefit from a common
library with a common implementation.  This also has the benefit of
removing a lot of open-coded bookkeeping and duplicate code for the two
drivers.

In this second series, the FDMA library will be taken into use by the
lan966x switch driver.

 ###################
 # Example of use: #
 ###################

- Initialize the rx and tx fdma structs with values for: number of
  DCB's, number of DB's, channel ID, DB size (data buffer size), and
  total size of the requested memory. Also provide two callbacks:
  nextptr_cb() and dataptr_cb() for getting the nextptr and dataptr.

- Allocate memory using fdma_alloc_phys() or fdma_alloc_coherent().

- Initialize the DCB's with fdma_dcb_init().

- Add new DCB's with fdma_dcb_add().

- Free memory with fdma_free_phys() or fdma_free_coherent().

 #####################
 # Patch  breakdown: #
 #####################

Patch #1:  select FDMA library for lan966x.

Patch #2:  includes the fdma_api.h header and removes old symbols.

Patch #3:  replaces old rx and tx variables with equivalent ones from the
           fdma struct. Only the variables that can be changed without
           breaking traffic is changed in this patch.

Patch #4:  uses the library for allocation of rx buffers. This requires
           quite a bit of refactoring in this single patch.

Patch #5:  uses the library for adding DCB's in the rx path.

Patch #6:  uses the library for freeing rx buffers.

Patch #7:  uses the library for allocation of tx buffers. This requires
           quite a bit of refactoring in this single patch.

Patch #8:  uses the library for adding DCB's in the tx path.

Patch #9:  uses the library helpers in the tx path.

Patch #10: ditch last_in_use variable and use library instead.

Patch #11: uses library helpers throughout.

Patch #12: refactor lan966x_fdma_reload() function.

[1] https://lore.kernel.org/netdev/20240902-fdma-sparx5-v1-0-1e7d5e5a9f34@microchip.com/

Signed-off-by: Daniel Machon <daniel.machon@microchip.com>
====================

Link: https://patch.msgid.link/20240905-fdma-lan966x-v1-0-e083f8620165@microchip.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
matttbe pushed a commit that referenced this issue Sep 12, 2024
mt7915_band_config() sets band_idx = 1 on the main phy for mt7986
with MT7975_ONE_ADIE or MT7976_ONE_ADIE.

Commit 0335c03 ("wifi: mt76: fix race condition related to
checking tx queue fill status") introduced a dereference of the
phys array indirectly indexed by band_idx via wcid->phy_idx in
mt76_wcid_cleanup(). This caused the following Oops on affected
mt7986 devices:

 Unable to handle kernel read from unreadable memory at virtual address 0000000000000024
 Mem abort info:
   ESR = 0x0000000096000005
   EC = 0x25: DABT (current EL), IL = 32 bits
   SET = 0, FnV = 0
   EA = 0, S1PTW = 0
   FSC = 0x05: level 1 translation fault
 Data abort info:
   ISV = 0, ISS = 0x00000005
   CM = 0, WnR = 0
 user pgtable: 4k pages, 39-bit VAs, pgdp=0000000042545000
 [0000000000000024] pgd=0000000000000000, p4d=0000000000000000, pud=0000000000000000
 Internal error: Oops: 0000000096000005 [#1] SMP
 Modules linked in: ... mt7915e mt76_connac_lib mt76 mac80211 cfg80211 ...
 CPU: 2 PID: 1631 Comm: hostapd Not tainted 5.15.150 #0
 Hardware name: ZyXEL EX5700 (Telenor) (DT)
 pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
 pc : mt76_wcid_cleanup+0x84/0x22c [mt76]
 lr : mt76_wcid_cleanup+0x64/0x22c [mt76]
 sp : ffffffc00a803700
 x29: ffffffc00a803700 x28: ffffff80008f7300 x27: ffffff80003f3c00
 x26: ffffff80000a7880 x25: ffffffc008c26e00 x24: 0000000000000001
 x23: ffffffc000a68114 x22: 0000000000000000 x21: ffffff8004172cc8
 x20: ffffffc00a803748 x19: ffffff8004152020 x18: 0000000000000000
 x17: 00000000000017c0 x16: ffffffc008ef5000 x15: 0000000000000be0
 x14: ffffff8004172e28 x13: ffffff8004172e28 x12: 0000000000000000
 x11: 0000000000000000 x10: ffffff8004172e30 x9 : ffffff8004172e28
 x8 : 0000000000000000 x7 : ffffff8004156020 x6 : 0000000000000000
 x5 : 0000000000000031 x4 : 0000000000000000 x3 : 0000000000000001
 x2 : 0000000000000000 x1 : ffffff80008f7300 x0 : 0000000000000024
 Call trace:
  mt76_wcid_cleanup+0x84/0x22c [mt76]
  __mt76_sta_remove+0x70/0xbc [mt76]
  mt76_sta_state+0x8c/0x1a4 [mt76]
  mt7915_eeprom_get_power_delta+0x11e4/0x23a0 [mt7915e]
  drv_sta_state+0x144/0x274 [mac80211]
  sta_info_move_state+0x1cc/0x2a4 [mac80211]
  sta_set_sinfo+0xaf8/0xc24 [mac80211]
  sta_info_destroy_addr_bss+0x4c/0x6c [mac80211]

  ieee80211_color_change_finish+0x1c08/0x1e70 [mac80211]
  cfg80211_check_station_change+0x1360/0x4710 [cfg80211]
  genl_family_rcv_msg_doit+0xb4/0x110
  genl_rcv_msg+0xd0/0x1bc
  netlink_rcv_skb+0x58/0x120
  genl_rcv+0x34/0x50
  netlink_unicast+0x1f0/0x2ec
  netlink_sendmsg+0x198/0x3d0
  ____sys_sendmsg+0x1b0/0x210
  ___sys_sendmsg+0x80/0xf0
  __sys_sendmsg+0x44/0xa0
  __arm64_sys_sendmsg+0x20/0x30
  invoke_syscall.constprop.0+0x4c/0xe0
  do_el0_svc+0x40/0xd0
  el0_svc+0x14/0x4c
  el0t_64_sync_handler+0x100/0x110
  el0t_64_sync+0x15c/0x160
 Code: d2800002 910092c0 52800023 f9800011 (885f7c01)
 ---[ end trace 7e42dd9a39ed2281 ]---

Fix by using mt76_dev_phy() which will map band_idx to the correct phy
for all hardware combinations.

Fixes: 0335c03 ("wifi: mt76: fix race condition related to checking tx queue fill status")
Link: openwrt/openwrt#14548
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Link: https://patch.msgid.link/20240713130010.516037-1-bjorn@mork.no
Signed-off-by: Felix Fietkau <nbd@nbd.name>
matttbe pushed a commit that referenced this issue Sep 12, 2024
Mina Almasry says:

====================
Device Memory TCP

Device memory TCP (devmem TCP) is a proposal for transferring data
to and/or from device memory efficiently, without bouncing the data
to a host memory buffer.

* Problem:

A large amount of data transfers have device memory as the source
and/or destination. Accelerators drastically increased the volume
of such transfers. Some examples include:

- ML accelerators transferring large amounts of training data from storage
  into GPU/TPU memory. In some cases ML training setup time can be as long
  as 50% of TPU compute time, improving data transfer throughput &
  efficiency can help improving GPU/TPU utilization.

- Distributed training, where ML accelerators, such as GPUs on different
  hosts, exchange data among them.

- Distributed raw block storage applications transfer large amounts of
  data with remote SSDs, much of this data does not require host
  processing.

Today, the majority of the Device-to-Device data transfers the network
are implemented as the following low level operations: Device-to-Host
copy, Host-to-Host network transfer, and Host-to-Device copy.

The implementation is suboptimal, especially for bulk data transfers,
and can put significant strains on system resources, such as host memory
bandwidth, PCIe bandwidth, etc. One important reason behind the current
state is the kernel’s lack of semantics to express device to network
transfers.

* Proposal:

In this patch series we attempt to optimize this use case by implementing
socket APIs that enable the user to:

1. send device memory across the network directly, and
2. receive incoming network packets directly into device memory.

Packet _payloads_ go directly from the NIC to device memory for receive
and from device memory to NIC for transmit.
Packet _headers_ go to/from host memory and are processed by the TCP/IP
stack normally. The NIC _must_ support header split to achieve this.

Advantages:

- Alleviate host memory bandwidth pressure, compared to existing
 network-transfer + device-copy semantics.

- Alleviate PCIe BW pressure, by limiting data transfer to the lowest level
  of the PCIe tree, compared to traditional path which sends data through
  the root complex.

* Patch overview:

** Part 1: netlink API

Gives user ability to bind dma-buf to an RX queue.

** Part 2: scatterlist support

Currently the standard for device memory sharing is DMABUF, which doesn't
generate struct pages. On the other hand, networking stack (skbs, drivers,
and page pool) operate on pages. We have 2 options:

1. Generate struct pages for dmabuf device memory, or,
2. Modify the networking stack to process scatterlist.

Approach #1 was attempted in RFC v1. RFC v2 implements approach #2.

** part 3: page pool support

We piggy back on page pool memory providers proposal:
https://github.com/kuba-moo/linux/tree/pp-providers

It allows the page pool to define a memory provider that provides the
page allocation and freeing. It helps abstract most of the device memory
TCP changes from the driver.

** part 4: support for unreadable skb frags

Page pool iovs are not accessible by the host; we implement changes
throughput the networking stack to correctly handle skbs with unreadable
frags.

** Part 5: recvmsg() APIs

We define user APIs for the user to send and receive device memory.

Not included with this series is the GVE devmem TCP support, just to
simplify the review. Code available here if desired:
https://github.com/mina/linux/tree/tcpdevmem

This series is built on top of net-next with Jakub's pp-providers changes
cherry-picked.

* NIC dependencies:

1. (strict) Devmem TCP require the NIC to support header split, i.e. the
   capability to split incoming packets into a header + payload and to put
   each into a separate buffer. Devmem TCP works by using device memory
   for the packet payload, and host memory for the packet headers.

2. (optional) Devmem TCP works better with flow steering support & RSS
   support, i.e. the NIC's ability to steer flows into certain rx queues.
   This allows the sysadmin to enable devmem TCP on a subset of the rx
   queues, and steer devmem TCP traffic onto these queues and non devmem
   TCP elsewhere.

The NIC I have access to with these properties is the GVE with DQO support
running in Google Cloud, but any NIC that supports these features would
suffice. I may be able to help reviewers bring up devmem TCP on their NICs.

* Testing:

The series includes a udmabuf kselftest that show a simple use case of
devmem TCP and validates the entire data path end to end without
a dependency on a specific dmabuf provider.

** Test Setup

Kernel: net-next with this series and memory provider API cherry-picked
locally.

Hardware: Google Cloud A3 VMs.

NIC: GVE with header split & RSS & flow steering support.
====================

Link: https://patch.msgid.link/20240910171458.219195-1-almasrymina@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
matttbe pushed a commit that referenced this issue Sep 13, 2024
Error out if kvm_mmu_reload() fails when pre-faulting memory, as trying to
fault-in SPTEs will fail miserably due to root.hpa pointing at garbage.

Note, kvm_mmu_reload() can return -EIO and thus trigger the WARN on -EIO
in kvm_vcpu_pre_fault_memory(), but all such paths also WARN, i.e. the
WARN isn't user-triggerable and won't run afoul of warn-on-panic because
the kernel would already be panicking.

  BUG: unable to handle page fault for address: 000029ffffffffe8
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  PGD 0 P4D 0
  Oops: Oops: 0000 [#1] PREEMPT SMP
  CPU: 22 PID: 1069 Comm: pre_fault_memor Not tainted 6.10.0-rc7-332d2c1d713e-next-vm #548
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
  RIP: 0010:is_page_fault_stale+0x3e/0xe0 [kvm]
  RSP: 0018:ffffc9000114bd48 EFLAGS: 00010206
  RAX: 00003fffffffffc0 RBX: ffff88810a07c080 RCX: ffffc9000114bd78
  RDX: ffff88810a07c080 RSI: ffffea0000000000 RDI: ffff88810a07c080
  RBP: ffffc9000114bd78 R08: 00007fa3c8c00000 R09: 8000000000000225
  R10: ffffea00043d7d80 R11: 0000000000000000 R12: ffff88810a07c080
  R13: 0000000100000000 R14: ffffc9000114be58 R15: 0000000000000000
  FS:  00007fa3c9da0740(0000) GS:ffff888277d80000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 000029ffffffffe8 CR3: 000000011d698000 CR4: 0000000000352eb0
  Call Trace:
   <TASK>
   kvm_tdp_page_fault+0xcc/0x160 [kvm]
   kvm_mmu_do_page_fault+0xfb/0x1f0 [kvm]
   kvm_arch_vcpu_pre_fault_memory+0xd0/0x1a0 [kvm]
   kvm_vcpu_ioctl+0x761/0x8c0 [kvm]
   __x64_sys_ioctl+0x82/0xb0
   do_syscall_64+0x5b/0x160
   entry_SYSCALL_64_after_hwframe+0x4b/0x53
   </TASK>
  Modules linked in: kvm_intel kvm
  CR2: 000029ffffffffe8
  ---[ end trace 0000000000000000 ]---

Fixes: 6e01b76 ("KVM: x86: Implement kvm_arch_vcpu_pre_fault_memory()")
Reported-by: syzbot+23786faffb695f17edaa@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/0000000000002b84dc061dd73544@google.com
Reviewed-by: Kai Huang <kai.huang@intel.com>
Tested-by: xingwei lee <xrivendell7@gmail.com>
Tested-by: yuxin wang <wang1315768607@163.com>
Link: https://lore.kernel.org/r/20240723000211.3352304-1-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
matttbe pushed a commit that referenced this issue Sep 13, 2024
Binder objects are processed and copied individually into the target
buffer during transactions. Any raw data in-between these objects is
copied as well. However, this raw data copy lacks an out-of-bounds
check. If the raw data exceeds the data section size then the copy
overwrites the offsets section. This eventually triggers an error that
attempts to unwind the processed objects. However, at this point the
offsets used to index these objects are now corrupted.

Unwinding with corrupted offsets can result in decrements of arbitrary
nodes and lead to their premature release. Other users of such nodes are
left with a dangling pointer triggering a use-after-free. This issue is
made evident by the following KASAN report (trimmed):

  ==================================================================
  BUG: KASAN: slab-use-after-free in _raw_spin_lock+0xe4/0x19c
  Write of size 4 at addr ffff47fc91598f04 by task binder-util/743

  CPU: 9 UID: 0 PID: 743 Comm: binder-util Not tainted 6.11.0-rc4 #1
  Hardware name: linux,dummy-virt (DT)
  Call trace:
   _raw_spin_lock+0xe4/0x19c
   binder_free_buf+0x128/0x434
   binder_thread_write+0x8a4/0x3260
   binder_ioctl+0x18f0/0x258c
  [...]

  Allocated by task 743:
   __kmalloc_cache_noprof+0x110/0x270
   binder_new_node+0x50/0x700
   binder_transaction+0x413c/0x6da8
   binder_thread_write+0x978/0x3260
   binder_ioctl+0x18f0/0x258c
  [...]

  Freed by task 745:
   kfree+0xbc/0x208
   binder_thread_read+0x1c5c/0x37d4
   binder_ioctl+0x16d8/0x258c
  [...]
  ==================================================================

To avoid this issue, let's check that the raw data copy is within the
boundaries of the data section.

Fixes: 6d98eb9 ("binder: avoid potential data leakage when copying txn")
Cc: Todd Kjos <tkjos@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Carlos Llamas <cmllamas@google.com>
Link: https://lore.kernel.org/r/20240822182353.2129600-1-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
matttbe pushed a commit that referenced this issue Sep 13, 2024
Fix circular locking dependency on runtime suspend.

<4> [74.952215] ======================================================
<4> [74.952217] WARNING: possible circular locking dependency detected
<4> [74.952219] 6.10.0-rc7-xe #1 Not tainted
<4> [74.952221] ------------------------------------------------------
<4> [74.952223] kworker/7:1/82 is trying to acquire lock:
<4> [74.952226] ffff888120548488 (&dev->mode_config.mutex){+.+.}-{3:3}, at: drm_modeset_lock_all+0x40/0x1e0 [drm]
<4> [74.952260]
but task is already holding lock:
<4> [74.952262] ffffffffa0ae59c0 (xe_pm_runtime_lockdep_map){+.+.}-{0:0}, at: xe_pm_runtime_suspend+0x2f/0x340 [xe]
<4> [74.952322]
which lock already depends on the new lock.

The commit 'b1d90a86 ("drm/xe: Use the encoder suspend helper also used
by the i915 driver")' didn't do anything wrong. It actually fixed a
critical bug, because the encoder_suspend was never getting actually
called because it was returning if (has_display(xe)) instead of
if (!has_display(xe)). However, this ended up introducing the encoder
suspend calls in the runtime routines as well, causing the circular
locking dependency.

Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/2304
Fixes: b1d90a8 ("drm/xe: Use the encoder suspend helper also used by the i915 driver")
Cc: Imre Deak <imre.deak@intel.com>
Reviewed-by: Jonathan Cavitt <jonathan.cavitt@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240830183507.298351-2-rodrigo.vivi@intel.com
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
(cherry picked from commit 8da19441d0a02b53e362df81843bb20db3a8006a)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
matttbe pushed a commit that referenced this issue Sep 13, 2024
…git/netfilter/nf

Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following batch contains two fixes from Florian Westphal:

Patch #1 fixes a sk refcount leak in nft_socket on mismatch.

Patch #2 fixes cgroupsv2 matching from containers due to incorrect
	 level in subtree.

netfilter pull request 24-09-12

* tag 'nf-24-09-12' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
  netfilter: nft_socket: make cgroupsv2 matching work with namespaces
  netfilter: nft_socket: fix sk refcount leaks
====================

Link: https://patch.msgid.link/20240911222520.3606-1-pablo@netfilter.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
matttbe pushed a commit that referenced this issue Sep 13, 2024
…_module_init()

Move nf flowtable bpf initialization in nf_flow_table module load
routine since nf_flow_table_bpf is part of nf_flow_table module and not
nf_flow_table_inet one. This patch allows to avoid the following kernel
warning running the reproducer below:

$modprobe nf_flow_table_inet
$rmmod nf_flow_table_inet
$modprobe nf_flow_table_inet
modprobe: ERROR: could not insert 'nf_flow_table_inet': Invalid argument

[  184.081501] ------------[ cut here ]------------
[  184.081527] WARNING: CPU: 0 PID: 1362 at kernel/bpf/btf.c:8206 btf_populate_kfunc_set+0x23c/0x330
[  184.081550] CPU: 0 UID: 0 PID: 1362 Comm: modprobe Kdump: loaded Not tainted 6.11.0-0.rc5.22.el10.x86_64 #1
[  184.081553] Hardware name: Red Hat OpenStack Compute, BIOS 1.14.0-1.module+el8.4.0+8855+a9e237a9 04/01/2014
[  184.081554] RIP: 0010:btf_populate_kfunc_set+0x23c/0x330
[  184.081558] RSP: 0018:ff22cfb38071fc90 EFLAGS: 00010202
[  184.081559] RAX: 0000000000000001 RBX: 0000000000000001 RCX: 0000000000000000
[  184.081560] RDX: 000000000000006e RSI: ffffffff95c00000 RDI: ff13805543436350
[  184.081561] RBP: ffffffffc0e22180 R08: ff13805543410808 R09: 000000000001ec00
[  184.081562] R10: ff13805541c8113c R11: 0000000000000010 R12: ff13805541b83c00
[  184.081563] R13: ff13805543410800 R14: 0000000000000001 R15: ffffffffc0e2259a
[  184.081564] FS:  00007fa436c46740(0000) GS:ff1380557ba00000(0000) knlGS:0000000000000000
[  184.081569] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  184.081570] CR2: 000055e7b3187000 CR3: 0000000100c48003 CR4: 0000000000771ef0
[  184.081571] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  184.081572] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  184.081572] PKRU: 55555554
[  184.081574] Call Trace:
[  184.081575]  <TASK>
[  184.081578]  ? show_trace_log_lvl+0x1b0/0x2f0
[  184.081580]  ? show_trace_log_lvl+0x1b0/0x2f0
[  184.081582]  ? __register_btf_kfunc_id_set+0x199/0x200
[  184.081585]  ? btf_populate_kfunc_set+0x23c/0x330
[  184.081586]  ? __warn.cold+0x93/0xed
[  184.081590]  ? btf_populate_kfunc_set+0x23c/0x330
[  184.081592]  ? report_bug+0xff/0x140
[  184.081594]  ? handle_bug+0x3a/0x70
[  184.081596]  ? exc_invalid_op+0x17/0x70
[  184.081597]  ? asm_exc_invalid_op+0x1a/0x20
[  184.081601]  ? btf_populate_kfunc_set+0x23c/0x330
[  184.081602]  __register_btf_kfunc_id_set+0x199/0x200
[  184.081605]  ? __pfx_nf_flow_inet_module_init+0x10/0x10 [nf_flow_table_inet]
[  184.081607]  do_one_initcall+0x58/0x300
[  184.081611]  do_init_module+0x60/0x230
[  184.081614]  __do_sys_init_module+0x17a/0x1b0
[  184.081617]  do_syscall_64+0x7d/0x160
[  184.081620]  ? __count_memcg_events+0x58/0xf0
[  184.081623]  ? handle_mm_fault+0x234/0x350
[  184.081626]  ? do_user_addr_fault+0x347/0x640
[  184.081630]  ? clear_bhb_loop+0x25/0x80
[  184.081633]  ? clear_bhb_loop+0x25/0x80
[  184.081634]  ? clear_bhb_loop+0x25/0x80
[  184.081637]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
[  184.081639] RIP: 0033:0x7fa43652e4ce
[  184.081647] RSP: 002b:00007ffe8213be18 EFLAGS: 00000246 ORIG_RAX: 00000000000000af
[  184.081649] RAX: ffffffffffffffda RBX: 000055e7b3176c20 RCX: 00007fa43652e4ce
[  184.081650] RDX: 000055e7737fde79 RSI: 0000000000003990 RDI: 000055e7b3185380
[  184.081651] RBP: 000055e7737fde79 R08: 0000000000000007 R09: 000055e7b3179bd0
[  184.081651] R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000040000
[  184.081652] R13: 000055e7b3176fa0 R14: 0000000000000000 R15: 000055e7b3179b80

Fixes: 391bb65 ("netfilter: Add bpf_xdp_flow_lookup kfunc")
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Acked-by: Florian Westphal <fw@strlen.de>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Link: https://patch.msgid.link/20240911-nf-flowtable-bpf-modprob-fix-v1-1-f9fc075aafc3@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
matttbe pushed a commit that referenced this issue Sep 16, 2024
Blamed commit accidentally removed a check for rt->rt6i_idev being NULL,
as spotted by syzbot:

Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 1 UID: 0 PID: 10998 Comm: syz-executor Not tainted 6.11.0-rc6-syzkaller-00208-g625403177711 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
 RIP: 0010:rt6_uncached_list_flush_dev net/ipv6/route.c:177 [inline]
 RIP: 0010:rt6_disable_ip+0x33e/0x7e0 net/ipv6/route.c:4914
Code: 41 80 3c 04 00 74 0a e8 90 d0 9b f7 48 8b 7c 24 08 48 8b 07 48 89 44 24 10 4c 89 f0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 4c 89 f7 e8 64 d0 9b f7 48 8b 44 24 18 49 39 06
RSP: 0018:ffffc900047374e0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 1ffff1100fdf8f33 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff88807efc78c0
RBP: ffffc900047375d0 R08: 0000000000000003 R09: fffff520008e6e8c
R10: dffffc0000000000 R11: fffff520008e6e8c R12: 1ffff1100fdf8f18
R13: ffff88807efc7998 R14: 0000000000000000 R15: ffff88807efc7930
FS:  0000000000000000(0000) GS:ffff8880b8900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020002a80 CR3: 0000000022f62000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
  addrconf_ifdown+0x15d/0x1bd0 net/ipv6/addrconf.c:3856
 addrconf_notify+0x3cb/0x1020
  notifier_call_chain+0x19f/0x3e0 kernel/notifier.c:93
  call_netdevice_notifiers_extack net/core/dev.c:2032 [inline]
  call_netdevice_notifiers net/core/dev.c:2046 [inline]
  unregister_netdevice_many_notify+0xd81/0x1c40 net/core/dev.c:11352
  unregister_netdevice_many net/core/dev.c:11414 [inline]
  unregister_netdevice_queue+0x303/0x370 net/core/dev.c:11289
  unregister_netdevice include/linux/netdevice.h:3129 [inline]
  __tun_detach+0x6b9/0x1600 drivers/net/tun.c:685
  tun_detach drivers/net/tun.c:701 [inline]
  tun_chr_close+0x108/0x1b0 drivers/net/tun.c:3510
  __fput+0x24a/0x8a0 fs/file_table.c:422
  task_work_run+0x24f/0x310 kernel/task_work.c:228
  exit_task_work include/linux/task_work.h:40 [inline]
  do_exit+0xa2f/0x27f0 kernel/exit.c:882
  do_group_exit+0x207/0x2c0 kernel/exit.c:1031
  __do_sys_exit_group kernel/exit.c:1042 [inline]
  __se_sys_exit_group kernel/exit.c:1040 [inline]
  __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1040
  x64_sys_call+0x2634/0x2640 arch/x86/include/generated/asm/syscalls_64.h:232
  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
  do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1acc77def9
Code: Unable to access opcode bytes at 0x7f1acc77decf.
RSP: 002b:00007ffeb26fa738 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f1acc77def9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000043
RBP: 00007f1acc7dd508 R08: 00007ffeb26f84d7 R09: 0000000000000003
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 0000000000000003 R14: 00000000ffffffff R15: 00007ffeb26fa8e0
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
 RIP: 0010:rt6_uncached_list_flush_dev net/ipv6/route.c:177 [inline]
 RIP: 0010:rt6_disable_ip+0x33e/0x7e0 net/ipv6/route.c:4914
Code: 41 80 3c 04 00 74 0a e8 90 d0 9b f7 48 8b 7c 24 08 48 8b 07 48 89 44 24 10 4c 89 f0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 4c 89 f7 e8 64 d0 9b f7 48 8b 44 24 18 49 39 06
RSP: 0018:ffffc900047374e0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 1ffff1100fdf8f33 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff88807efc78c0
RBP: ffffc900047375d0 R08: 0000000000000003 R09: fffff520008e6e8c
R10: dffffc0000000000 R11: fffff520008e6e8c R12: 1ffff1100fdf8f18
R13: ffff88807efc7998 R14: 0000000000000000 R15: ffff88807efc7930
FS:  0000000000000000(0000) GS:ffff8880b8900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020002a80 CR3: 0000000022f62000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Fixes: e332bc6 ("ipv6: Don't call with rt6_uncached_list_flush_dev")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: David Ahern <dsahern@kernel.org>
Acked-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://patch.msgid.link/20240913083147.3095442-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
matttbe pushed a commit that referenced this issue Sep 16, 2024
Ido Schimmel says:

====================
net: fib_rules: Add DSCP selector support

Currently, the kernel rejects IPv4 FIB rules that try to match on the
upper three DSCP bits:

 # ip -4 rule add tos 0x1c table 100
 # ip -4 rule add tos 0x3c table 100
 Error: Invalid tos.

The reason for that is that historically users of the FIB lookup API
only populated the lower three DSCP bits in the TOS field of the IPv4
flow key ('flowi4_tos'), which fits the TOS definition from the initial
IPv4 specification (RFC 791).

This is not very useful nowadays and instead some users want to be able
to match on the six bits DSCP field, which replaced the TOS and IP
precedence fields over 25 years ago (RFC 2474). In addition, the current
behavior differs between IPv4 and IPv6 which does allow users to match
on the entire DSCP field using the TOS selector.

Recent patchsets made sure that callers of the FIB lookup API now
populate the entire DSCP field in the IPv4 flow key. Therefore, it is
now possible to extend FIB rules to match on DSCP.

This is done by adding a new DSCP attribute which is implemented for
both IPv4 and IPv6 to provide user space programs a consistent behavior
between both address families.

The behavior of the old TOS selector is unchanged and IPv4 FIB rules
using it will only match on the lower three DSCP bits. The kernel will
reject rules that try to use both selectors.

Patch #1 adds the new DSCP attribute but rejects its usage.

Patches #2-#3 implement IPv4 and IPv6 support.

Patch #4 allows user space to use the new attribute.

Patches #5-#6 add selftests.
====================

Link: https://patch.msgid.link/20240911093748.3662015-1-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
matttbe pushed a commit that referenced this issue Sep 16, 2024
Nelson Escobar says:

====================
enic: Report per queue stats

Patch #1: Use a macro instead of static const variables for array sizes.  I
          didn't want to add more static const variables in the next patch
          so clean up the existing ones first.

Patch #2: Collect per queue statistics

Patch #3: Report per queue stats in netdev qstats

Patch #4: Report some per queue stats in ethtool

 # NETIF="eno6" tools/testing/selftests/drivers/net/stats.py
KTAP version 1
1..5
ok 1 stats.check_pause # XFAIL pause not supported by the device
ok 2 stats.check_fec # XFAIL FEC not supported by the device
ok 3 stats.pkt_byte_sum
ok 4 stats.qstat_by_ifindex
ok 5 stats.check_down

 # tools/net/ynl/cli.py --spec Documentation/netlink/specs/netdev.yaml \
     --dump qstats-get --json '{"ifindex": "34"}'
[{'ifindex': 34,
  'rx-bytes': 66762680,
  'rx-csum-unnecessary': 1009345,
  'rx-hw-drop-overruns': 0,
  'rx-hw-drops': 0,
  'rx-packets': 1009673,
  'tx-bytes': 137936674899,
  'tx-csum-none': 125,
  'tx-hw-gso-packets': 2408712,
  'tx-needs-csum': 2431531,
  'tx-packets': 15475466,
  'tx-stop': 0,
  'tx-wake': 0}]

v2: https://lore.kernel.org/20240905010900.24152-1-neescoba@cisco.com
v1: https://lore.kernel.org/20240823235401.29996-1-neescoba@cisco.com
====================

Link: https://patch.msgid.link/20240912005039.10797-1-neescoba@cisco.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
matttbe pushed a commit that referenced this issue Sep 17, 2024
Buffer 'card->dai_link' is reallocated in 'meson_card_reallocate_links()',
so move 'pad' pointer initialization after this function when memory is
already reallocated.

Kasan bug report:

==================================================================
BUG: KASAN: slab-use-after-free in axg_card_add_link+0x76c/0x9bc
Read of size 8 at addr ffff000000e8b260 by task modprobe/356

CPU: 0 PID: 356 Comm: modprobe Tainted: G O 6.9.12-sdkernel #1
Call trace:
 dump_backtrace+0x94/0xec
 show_stack+0x18/0x24
 dump_stack_lvl+0x78/0x90
 print_report+0xfc/0x5c0
 kasan_report+0xb8/0xfc
 __asan_load8+0x9c/0xb8
 axg_card_add_link+0x76c/0x9bc [snd_soc_meson_axg_sound_card]
 meson_card_probe+0x344/0x3b8 [snd_soc_meson_card_utils]
 platform_probe+0x8c/0xf4
 really_probe+0x110/0x39c
 __driver_probe_device+0xb8/0x18c
 driver_probe_device+0x108/0x1d8
 __driver_attach+0xd0/0x25c
 bus_for_each_dev+0xe0/0x154
 driver_attach+0x34/0x44
 bus_add_driver+0x134/0x294
 driver_register+0xa8/0x1e8
 __platform_driver_register+0x44/0x54
 axg_card_pdrv_init+0x20/0x1000 [snd_soc_meson_axg_sound_card]
 do_one_initcall+0xdc/0x25c
 do_init_module+0x10c/0x334
 load_module+0x24c4/0x26cc
 init_module_from_file+0xd4/0x128
 __arm64_sys_finit_module+0x1f4/0x41c
 invoke_syscall+0x60/0x188
 el0_svc_common.constprop.0+0x78/0x13c
 do_el0_svc+0x30/0x40
 el0_svc+0x38/0x78
 el0t_64_sync_handler+0x100/0x12c
 el0t_64_sync+0x190/0x194

Fixes: 7864a79 ("ASoC: meson: add axg sound card support")
Cc: Stable@vger.kernel.org
Signed-off-by: Arseniy Krasnov <avkrasnov@salutedevices.com>
Reviewed-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://patch.msgid.link/20240911142425.598631-1-avkrasnov@salutedevices.com
Signed-off-by: Mark Brown <broonie@kernel.org>
matttbe pushed a commit that referenced this issue Sep 17, 2024
Marc Hartmayer reported:
        [   23.133876] Unable to handle kernel pointer dereference in virtual kernel address space
        [   23.133950] Failing address: 0000000000000000 TEID: 0000000000000483
        [   23.133954] Fault in home space mode while using kernel ASCE.
        [   23.133957] AS:000000001b8f0007 R3:0000000056cf4007 S:0000000056cf3800 P:000000000000003d
        [   23.134207] Oops: 0004 ilc:2 [#1] SMP
	(snip)
        [   23.134516] Call Trace:
        [   23.134520]  [<0000024e326caf28>] worker_thread+0x48/0x430
        [   23.134525] ([<0000024e326caf18>] worker_thread+0x38/0x430)
        [   23.134528]  [<0000024e326d3a3e>] kthread+0x11e/0x130
        [   23.134533]  [<0000024e3264b0dc>] __ret_from_fork+0x3c/0x60
        [   23.134536]  [<0000024e333fb37a>] ret_from_fork+0xa/0x38
        [   23.134552] Last Breaking-Event-Address:
        [   23.134553]  [<0000024e333f4c04>] mutex_unlock+0x24/0x30
        [   23.134562] Kernel panic - not syncing: Fatal exception: panic_on_oops

With debuging and analysis, worker_thread() accesses to the nullified
worker->pool when the newly created worker is destroyed before being
waken-up, in which case worker_thread() can see the result detach_worker()
reseting worker->pool to NULL at the begining.

Move the code "worker->pool = NULL;" out from detach_worker() to fix the
problem.

worker->pool had been designed to be constant for regular workers and
changeable for rescuer. To share attaching/detaching code for regular
and rescuer workers and to avoid worker->pool being accessed inadvertently
when the worker has been detached, worker->pool is reset to NULL when
detached no matter the worker is rescuer or not.

To maintain worker->pool being reset after detached, move the code
"worker->pool = NULL;" in the worker thread context after detached.

It is either be in the regular worker thread context after PF_WQ_WORKER
is cleared or in rescuer worker thread context with wq_pool_attach_mutex
held. So it is safe to do so.

Cc: Marc Hartmayer <mhartmay@linux.ibm.com>
Link: https://lore.kernel.org/lkml/87wmjj971b.fsf@linux.ibm.com/
Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Fixes: f4b7b53 ("workqueue: Detach workers directly in idle_cull_fn()")
Cc: stable@vger.kernel.org # v6.11+
Signed-off-by: Lai Jiangshan <jiangshan.ljs@antgroup.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
matttbe pushed a commit that referenced this issue Sep 24, 2024
We have some machines running stock Ubuntu 20.04.6 which is their 5.4.0-174-generic
kernel that are running ceph and recently hit a null ptr dereference in
tcp_rearm_rto(). Initially hitting it from the TLP path, but then later we also
saw it getting hit from the RACK case as well. Here are examples of the oops
messages we saw in each of those cases:

Jul 26 15:05:02 rx [11061395.780353] BUG: kernel NULL pointer dereference, address: 0000000000000020
Jul 26 15:05:02 rx [11061395.787572] #PF: supervisor read access in kernel mode
Jul 26 15:05:02 rx [11061395.792971] #PF: error_code(0x0000) - not-present page
Jul 26 15:05:02 rx [11061395.798362] PGD 0 P4D 0
Jul 26 15:05:02 rx [11061395.801164] Oops: 0000 [#1] SMP NOPTI
Jul 26 15:05:02 rx [11061395.805091] CPU: 0 PID: 9180 Comm: msgr-worker-1 Tainted: G W 5.4.0-174-generic #193-Ubuntu
Jul 26 15:05:02 rx [11061395.814996] Hardware name: Supermicro SMC 2x26 os-gen8 64C NVME-Y 256G/H12SSW-NTR, BIOS 2.5.V1.2U.NVMe.UEFI 05/09/2023
Jul 26 15:05:02 rx [11061395.825952] RIP: 0010:tcp_rearm_rto+0xe4/0x160
Jul 26 15:05:02 rx [11061395.830656] Code: 87 ca 04 00 00 00 5b 41 5c 41 5d 5d c3 c3 49 8b bc 24 40 06 00 00 eb 8d 48 bb cf f7 53 e3 a5 9b c4 20 4c 89 ef e8 0c fe 0e 00 <48> 8b 78 20 48 c1 ef 03 48 89 f8 41 8b bc 24 80 04 00 00 48 f7 e3
Jul 26 15:05:02 rx [11061395.849665] RSP: 0018:ffffb75d40003e08 EFLAGS: 00010246
Jul 26 15:05:02 rx [11061395.855149] RAX: 0000000000000000 RBX: 20c49ba5e353f7cf RCX: 0000000000000000
Jul 26 15:05:02 rx [11061395.862542] RDX: 0000000062177c30 RSI: 000000000000231c RDI: ffff9874ad283a60
Jul 26 15:05:02 rx [11061395.869933] RBP: ffffb75d40003e20 R08: 0000000000000000 R09: ffff987605e20aa8
Jul 26 15:05:02 rx [11061395.877318] R10: ffffb75d40003f00 R11: ffffb75d4460f740 R12: ffff9874ad283900
Jul 26 15:05:02 rx [11061395.884710] R13: ffff9874ad283a60 R14: ffff9874ad283980 R15: ffff9874ad283d30
Jul 26 15:05:02 rx [11061395.892095] FS: 00007f1ef4a2e700(0000) GS:ffff987605e00000(0000) knlGS:0000000000000000
Jul 26 15:05:02 rx [11061395.900438] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
Jul 26 15:05:02 rx [11061395.906435] CR2: 0000000000000020 CR3: 0000003e450ba003 CR4: 0000000000760ef0
Jul 26 15:05:02 rx [11061395.913822] PKRU: 55555554
Jul 26 15:05:02 rx [11061395.916786] Call Trace:
Jul 26 15:05:02 rx [11061395.919488]
Jul 26 15:05:02 rx [11061395.921765] ? show_regs.cold+0x1a/0x1f
Jul 26 15:05:02 rx [11061395.925859] ? __die+0x90/0xd9
Jul 26 15:05:02 rx [11061395.929169] ? no_context+0x196/0x380
Jul 26 15:05:02 rx [11061395.933088] ? ip6_protocol_deliver_rcu+0x4e0/0x4e0
Jul 26 15:05:02 rx [11061395.938216] ? ip6_sublist_rcv_finish+0x3d/0x50
Jul 26 15:05:02 rx [11061395.943000] ? __bad_area_nosemaphore+0x50/0x1a0
Jul 26 15:05:02 rx [11061395.947873] ? bad_area_nosemaphore+0x16/0x20
Jul 26 15:05:02 rx [11061395.952486] ? do_user_addr_fault+0x267/0x450
Jul 26 15:05:02 rx [11061395.957104] ? ipv6_list_rcv+0x112/0x140
Jul 26 15:05:02 rx [11061395.961279] ? __do_page_fault+0x58/0x90
Jul 26 15:05:02 rx [11061395.965458] ? do_page_fault+0x2c/0xe0
Jul 26 15:05:02 rx [11061395.969465] ? page_fault+0x34/0x40
Jul 26 15:05:02 rx [11061395.973217] ? tcp_rearm_rto+0xe4/0x160
Jul 26 15:05:02 rx [11061395.977313] ? tcp_rearm_rto+0xe4/0x160
Jul 26 15:05:02 rx [11061395.981408] tcp_send_loss_probe+0x10b/0x220
Jul 26 15:05:02 rx [11061395.985937] tcp_write_timer_handler+0x1b4/0x240
Jul 26 15:05:02 rx [11061395.990809] tcp_write_timer+0x9e/0xe0
Jul 26 15:05:02 rx [11061395.994814] ? tcp_write_timer_handler+0x240/0x240
Jul 26 15:05:02 rx [11061395.999866] call_timer_fn+0x32/0x130
Jul 26 15:05:02 rx [11061396.003782] __run_timers.part.0+0x180/0x280
Jul 26 15:05:02 rx [11061396.008309] ? recalibrate_cpu_khz+0x10/0x10
Jul 26 15:05:02 rx [11061396.012841] ? native_x2apic_icr_write+0x30/0x30
Jul 26 15:05:02 rx [11061396.017718] ? lapic_next_event+0x21/0x30
Jul 26 15:05:02 rx [11061396.021984] ? clockevents_program_event+0x8f/0xe0
Jul 26 15:05:02 rx [11061396.027035] run_timer_softirq+0x2a/0x50
Jul 26 15:05:02 rx [11061396.031212] __do_softirq+0xd1/0x2c1
Jul 26 15:05:02 rx [11061396.035044] do_softirq_own_stack+0x2a/0x40
Jul 26 15:05:02 rx [11061396.039480]
Jul 26 15:05:02 rx [11061396.041840] do_softirq.part.0+0x46/0x50
Jul 26 15:05:02 rx [11061396.046022] __local_bh_enable_ip+0x50/0x60
Jul 26 15:05:02 rx [11061396.050460] _raw_spin_unlock_bh+0x1e/0x20
Jul 26 15:05:02 rx [11061396.054817] nf_conntrack_tcp_packet+0x29e/0xbe0 [nf_conntrack]
Jul 26 15:05:02 rx [11061396.060994] ? get_l4proto+0xe7/0x190 [nf_conntrack]
Jul 26 15:05:02 rx [11061396.066220] nf_conntrack_in+0xe9/0x670 [nf_conntrack]
Jul 26 15:05:02 rx [11061396.071618] ipv6_conntrack_local+0x14/0x20 [nf_conntrack]
Jul 26 15:05:02 rx [11061396.077356] nf_hook_slow+0x45/0xb0
Jul 26 15:05:02 rx [11061396.081098] ip6_xmit+0x3f0/0x5d0
Jul 26 15:05:02 rx [11061396.084670] ? ipv6_anycast_cleanup+0x50/0x50
Jul 26 15:05:02 rx [11061396.089282] ? __sk_dst_check+0x38/0x70
Jul 26 15:05:02 rx [11061396.093381] ? inet6_csk_route_socket+0x13b/0x200
Jul 26 15:05:02 rx [11061396.098346] inet6_csk_xmit+0xa7/0xf0
Jul 26 15:05:02 rx [11061396.102263] __tcp_transmit_skb+0x550/0xb30
Jul 26 15:05:02 rx [11061396.106701] tcp_write_xmit+0x3c6/0xc20
Jul 26 15:05:02 rx [11061396.110792] ? __alloc_skb+0x98/0x1d0
Jul 26 15:05:02 rx [11061396.114708] __tcp_push_pending_frames+0x37/0x100
Jul 26 15:05:02 rx [11061396.119667] tcp_push+0xfd/0x100
Jul 26 15:05:02 rx [11061396.123150] tcp_sendmsg_locked+0xc70/0xdd0
Jul 26 15:05:02 rx [11061396.127588] tcp_sendmsg+0x2d/0x50
Jul 26 15:05:02 rx [11061396.131245] inet6_sendmsg+0x43/0x70
Jul 26 15:05:02 rx [11061396.135075] __sock_sendmsg+0x48/0x70
Jul 26 15:05:02 rx [11061396.138994] ____sys_sendmsg+0x212/0x280
Jul 26 15:05:02 rx [11061396.143172] ___sys_sendmsg+0x88/0xd0
Jul 26 15:05:02 rx [11061396.147098] ? __seccomp_filter+0x7e/0x6b0
Jul 26 15:05:02 rx [11061396.151446] ? __switch_to+0x39c/0x460
Jul 26 15:05:02 rx [11061396.155453] ? __switch_to_asm+0x42/0x80
Jul 26 15:05:02 rx [11061396.159636] ? __switch_to_asm+0x5a/0x80
Jul 26 15:05:02 rx [11061396.163816] __sys_sendmsg+0x5c/0xa0
Jul 26 15:05:02 rx [11061396.167647] __x64_sys_sendmsg+0x1f/0x30
Jul 26 15:05:02 rx [11061396.171832] do_syscall_64+0x57/0x190
Jul 26 15:05:02 rx [11061396.175748] entry_SYSCALL_64_after_hwframe+0x5c/0xc1
Jul 26 15:05:02 rx [11061396.181055] RIP: 0033:0x7f1ef692618d
Jul 26 15:05:02 rx [11061396.184893] Code: 28 89 54 24 1c 48 89 74 24 10 89 7c 24 08 e8 ca ee ff ff 8b 54 24 1c 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 2f 44 89 c7 48 89 44 24 08 e8 fe ee ff ff 48
Jul 26 15:05:02 rx [11061396.203889] RSP: 002b:00007f1ef4a26aa0 EFLAGS: 00000293 ORIG_RAX: 000000000000002e
Jul 26 15:05:02 rx [11061396.211708] RAX: ffffffffffffffda RBX: 000000000000084b RCX: 00007f1ef692618d
Jul 26 15:05:02 rx [11061396.219091] RDX: 0000000000004000 RSI: 00007f1ef4a26b10 RDI: 0000000000000275
Jul 26 15:05:02 rx [11061396.226475] RBP: 0000000000004000 R08: 0000000000000000 R09: 0000000000000020
Jul 26 15:05:02 rx [11061396.233859] R10: 0000000000000000 R11: 0000000000000293 R12: 000000000000084b
Jul 26 15:05:02 rx [11061396.241243] R13: 00007f1ef4a26b10 R14: 0000000000000275 R15: 000055592030f1e8
Jul 26 15:05:02 rx [11061396.248628] Modules linked in: vrf bridge stp llc vxlan ip6_udp_tunnel udp_tunnel nls_iso8859_1 amd64_edac_mod edac_mce_amd kvm_amd kvm crct10dif_pclmul ghash_clmulni_intel aesni_intel crypto_simd cryptd glue_helper wmi_bmof ipmi_ssif input_leds joydev rndis_host cdc_ether usbnet mii ast drm_vram_helper ttm drm_kms_helper i2c_algo_bit fb_sys_fops syscopyarea sysfillrect sysimgblt ccp mac_hid ipmi_si ipmi_devintf ipmi_msghandler nft_ct sch_fq_codel nf_tables_set nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 nf_tables nfnetlink ramoops reed_solomon efi_pstore drm ip_tables x_tables autofs4 raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c raid0 multipath linear mlx5_ib ib_uverbs ib_core raid1 mlx5_core hid_generic pci_hyperv_intf crc32_pclmul tls usbhid ahci mlxfw bnxt_en libahci hid nvme i2c_piix4 nvme_core wmi
Jul 26 15:05:02 rx [11061396.324334] CR2: 0000000000000020
Jul 26 15:05:02 rx [11061396.327944] ---[ end trace 68a2b679d1cfb4f1 ]---
Jul 26 15:05:02 rx [11061396.433435] RIP: 0010:tcp_rearm_rto+0xe4/0x160
Jul 26 15:05:02 rx [11061396.438137] Code: 87 ca 04 00 00 00 5b 41 5c 41 5d 5d c3 c3 49 8b bc 24 40 06 00 00 eb 8d 48 bb cf f7 53 e3 a5 9b c4 20 4c 89 ef e8 0c fe 0e 00 <48> 8b 78 20 48 c1 ef 03 48 89 f8 41 8b bc 24 80 04 00 00 48 f7 e3
Jul 26 15:05:02 rx [11061396.457144] RSP: 0018:ffffb75d40003e08 EFLAGS: 00010246
Jul 26 15:05:02 rx [11061396.462629] RAX: 0000000000000000 RBX: 20c49ba5e353f7cf RCX: 0000000000000000
Jul 26 15:05:02 rx [11061396.470012] RDX: 0000000062177c30 RSI: 000000000000231c RDI: ffff9874ad283a60
Jul 26 15:05:02 rx [11061396.477396] RBP: ffffb75d40003e20 R08: 0000000000000000 R09: ffff987605e20aa8
Jul 26 15:05:02 rx [11061396.484779] R10: ffffb75d40003f00 R11: ffffb75d4460f740 R12: ffff9874ad283900
Jul 26 15:05:02 rx [11061396.492164] R13: ffff9874ad283a60 R14: ffff9874ad283980 R15: ffff9874ad283d30
Jul 26 15:05:02 rx [11061396.499547] FS: 00007f1ef4a2e700(0000) GS:ffff987605e00000(0000) knlGS:0000000000000000
Jul 26 15:05:02 rx [11061396.507886] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
Jul 26 15:05:02 rx [11061396.513884] CR2: 0000000000000020 CR3: 0000003e450ba003 CR4: 0000000000760ef0
Jul 26 15:05:02 rx [11061396.521267] PKRU: 55555554
Jul 26 15:05:02 rx [11061396.524230] Kernel panic - not syncing: Fatal exception in interrupt
Jul 26 15:05:02 rx [11061396.530885] Kernel Offset: 0x1b200000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
Jul 26 15:05:03 rx [11061396.660181] ---[ end Kernel panic - not syncing: Fatal
 exception in interrupt ]---

After we hit this we disabled TLP by setting tcp_early_retrans to 0 and then hit the crash in the RACK case:

Aug 7 07:26:16 rx [1006006.265582] BUG: kernel NULL pointer dereference, address: 0000000000000020
Aug 7 07:26:16 rx [1006006.272719] #PF: supervisor read access in kernel mode
Aug 7 07:26:16 rx [1006006.278030] #PF: error_code(0x0000) - not-present page
Aug 7 07:26:16 rx [1006006.283343] PGD 0 P4D 0
Aug 7 07:26:16 rx [1006006.286057] Oops: 0000 [#1] SMP NOPTI
Aug 7 07:26:16 rx [1006006.289896] CPU: 5 PID: 0 Comm: swapper/5 Tainted: G W 5.4.0-174-generic #193-Ubuntu
Aug 7 07:26:16 rx [1006006.299107] Hardware name: Supermicro SMC 2x26 os-gen8 64C NVME-Y 256G/H12SSW-NTR, BIOS 2.5.V1.2U.NVMe.UEFI 05/09/2023
Aug 7 07:26:16 rx [1006006.309970] RIP: 0010:tcp_rearm_rto+0xe4/0x160
Aug 7 07:26:16 rx [1006006.314584] Code: 87 ca 04 00 00 00 5b 41 5c 41 5d 5d c3 c3 49 8b bc 24 40 06 00 00 eb 8d 48 bb cf f7 53 e3 a5 9b c4 20 4c 89 ef e8 0c fe 0e 00 <48> 8b 78 20 48 c1 ef 03 48 89 f8 41 8b bc 24 80 04 00 00 48 f7 e3
Aug 7 07:26:16 rx [1006006.333499] RSP: 0018:ffffb42600a50960 EFLAGS: 00010246
Aug 7 07:26:16 rx [1006006.338895] RAX: 0000000000000000 RBX: 20c49ba5e353f7cf RCX: 0000000000000000
Aug 7 07:26:16 rx [1006006.346193] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff92d687ed8160
Aug 7 07:26:16 rx [1006006.353489] RBP: ffffb42600a50978 R08: 0000000000000000 R09: 00000000cd896dcc
Aug 7 07:26:16 rx [1006006.360786] R10: ffff92dc3404f400 R11: 0000000000000001 R12: ffff92d687ed8000
Aug 7 07:26:16 rx [1006006.368084] R13: ffff92d687ed8160 R14: 00000000cd896dcc R15: 00000000cd8fca81
Aug 7 07:26:16 rx [1006006.375381] FS: 0000000000000000(0000) GS:ffff93158ad40000(0000) knlGS:0000000000000000
Aug 7 07:26:16 rx [1006006.383632] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
Aug 7 07:26:16 rx [1006006.389544] CR2: 0000000000000020 CR3: 0000003e775ce006 CR4: 0000000000760ee0
Aug 7 07:26:16 rx [1006006.396839] PKRU: 55555554
Aug 7 07:26:16 rx [1006006.399717] Call Trace:
Aug 7 07:26:16 rx [1006006.402335]
Aug 7 07:26:16 rx [1006006.404525] ? show_regs.cold+0x1a/0x1f
Aug 7 07:26:16 rx [1006006.408532] ? __die+0x90/0xd9
Aug 7 07:26:16 rx [1006006.411760] ? no_context+0x196/0x380
Aug 7 07:26:16 rx [1006006.415599] ? __bad_area_nosemaphore+0x50/0x1a0
Aug 7 07:26:16 rx [1006006.420392] ? _raw_spin_lock+0x1e/0x30
Aug 7 07:26:16 rx [1006006.424401] ? bad_area_nosemaphore+0x16/0x20
Aug 7 07:26:16 rx [1006006.428927] ? do_user_addr_fault+0x267/0x450
Aug 7 07:26:16 rx [1006006.433450] ? __do_page_fault+0x58/0x90
Aug 7 07:26:16 rx [1006006.437542] ? do_page_fault+0x2c/0xe0
Aug 7 07:26:16 rx [1006006.441470] ? page_fault+0x34/0x40
Aug 7 07:26:16 rx [1006006.445134] ? tcp_rearm_rto+0xe4/0x160
Aug 7 07:26:16 rx [1006006.449145] tcp_ack+0xa32/0xb30
Aug 7 07:26:16 rx [1006006.452542] tcp_rcv_established+0x13c/0x670
Aug 7 07:26:16 rx [1006006.456981] ? sk_filter_trim_cap+0x48/0x220
Aug 7 07:26:16 rx [1006006.461419] tcp_v6_do_rcv+0xdb/0x450
Aug 7 07:26:16 rx [1006006.465257] tcp_v6_rcv+0xc2b/0xd10
Aug 7 07:26:16 rx [1006006.468918] ip6_protocol_deliver_rcu+0xd3/0x4e0
Aug 7 07:26:16 rx [1006006.473706] ip6_input_finish+0x15/0x20
Aug 7 07:26:16 rx [1006006.477710] ip6_input+0xa2/0xb0
Aug 7 07:26:16 rx [1006006.481109] ? ip6_protocol_deliver_rcu+0x4e0/0x4e0
Aug 7 07:26:16 rx [1006006.486151] ip6_sublist_rcv_finish+0x3d/0x50
Aug 7 07:26:16 rx [1006006.490679] ip6_sublist_rcv+0x1aa/0x250
Aug 7 07:26:16 rx [1006006.494779] ? ip6_rcv_finish_core.isra.0+0xa0/0xa0
Aug 7 07:26:16 rx [1006006.499828] ipv6_list_rcv+0x112/0x140
Aug 7 07:26:16 rx [1006006.503748] __netif_receive_skb_list_core+0x1a4/0x250
Aug 7 07:26:16 rx [1006006.509057] netif_receive_skb_list_internal+0x1a1/0x2b0
Aug 7 07:26:16 rx [1006006.514538] gro_normal_list.part.0+0x1e/0x40
Aug 7 07:26:16 rx [1006006.519068] napi_complete_done+0x91/0x130
Aug 7 07:26:16 rx [1006006.523352] mlx5e_napi_poll+0x18e/0x610 [mlx5_core]
Aug 7 07:26:16 rx [1006006.528481] net_rx_action+0x142/0x390
Aug 7 07:26:16 rx [1006006.532398] __do_softirq+0xd1/0x2c1
Aug 7 07:26:16 rx [1006006.536142] irq_exit+0xae/0xb0
Aug 7 07:26:16 rx [1006006.539452] do_IRQ+0x5a/0xf0
Aug 7 07:26:16 rx [1006006.542590] common_interrupt+0xf/0xf
Aug 7 07:26:16 rx [1006006.546421]
Aug 7 07:26:16 rx [1006006.548695] RIP: 0010:native_safe_halt+0xe/0x10
Aug 7 07:26:16 rx [1006006.553399] Code: 7b ff ff ff eb bd 90 90 90 90 90 90 e9 07 00 00 00 0f 00 2d 36 2c 50 00 f4 c3 66 90 e9 07 00 00 00 0f 00 2d 26 2c 50 00 fb f4 90 0f 1f 44 00 00 55 48 89 e5 41 55 41 54 53 e8 dd 5e 61 ff 65
Aug 7 07:26:16 rx [1006006.572309] RSP: 0018:ffffb42600177e70 EFLAGS: 00000246 ORIG_RAX: ffffffffffffffc2
Aug 7 07:26:16 rx [1006006.580040] RAX: ffffffff8ed08b20 RBX: 0000000000000005 RCX: 0000000000000001
Aug 7 07:26:16 rx [1006006.587337] RDX: 00000000f48eeca2 RSI: 0000000000000082 RDI: 0000000000000082
Aug 7 07:26:16 rx [1006006.594635] RBP: ffffb42600177e90 R08: 0000000000000000 R09: 000000000000020f
Aug 7 07:26:16 rx [1006006.601931] R10: 0000000000100000 R11: 0000000000000000 R12: 0000000000000005
Aug 7 07:26:16 rx [1006006.609229] R13: ffff93157deb5f00 R14: 0000000000000000 R15: 0000000000000000
Aug 7 07:26:16 rx [1006006.616530] ? __cpuidle_text_start+0x8/0x8
Aug 7 07:26:16 rx [1006006.620886] ? default_idle+0x20/0x140
Aug 7 07:26:16 rx [1006006.624804] arch_cpu_idle+0x15/0x20
Aug 7 07:26:16 rx [1006006.628545] default_idle_call+0x23/0x30
Aug 7 07:26:16 rx [1006006.632640] do_idle+0x1fb/0x270
Aug 7 07:26:16 rx [1006006.636035] cpu_startup_entry+0x20/0x30
Aug 7 07:26:16 rx [1006006.640126] start_secondary+0x178/0x1d0
Aug 7 07:26:16 rx [1006006.644218] secondary_startup_64+0xa4/0xb0
Aug 7 07:26:17 rx [1006006.648568] Modules linked in: vrf bridge stp llc vxlan ip6_udp_tunnel udp_tunnel nls_iso8859_1 nft_ct amd64_edac_mod edac_mce_amd kvm_amd kvm crct10dif_pclmul ghash_clmulni_intel aesni_intel crypto_simd cryptd glue_helper wmi_bmof ipmi_ssif input_leds joydev rndis_host cdc_ether usbnet ast mii drm_vram_helper ttm drm_kms_helper i2c_algo_bit fb_sys_fops syscopyarea sysfillrect sysimgblt ccp mac_hid ipmi_si ipmi_devintf ipmi_msghandler sch_fq_codel nf_tables_set nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 nf_tables nfnetlink ramoops reed_solomon efi_pstore drm ip_tables x_tables autofs4 raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c raid0 multipath linear mlx5_ib ib_uverbs ib_core raid1 hid_generic mlx5_core pci_hyperv_intf crc32_pclmul usbhid ahci tls mlxfw bnxt_en hid libahci nvme i2c_piix4 nvme_core wmi [last unloaded: cpuid]
Aug 7 07:26:17 rx [1006006.726180] CR2: 0000000000000020
Aug 7 07:26:17 rx [1006006.729718] ---[ end trace e0e2e37e4e612984 ]---

Prior to seeing the first crash and on other machines we also see the warning in
tcp_send_loss_probe() where packets_out is non-zero, but both transmit and retrans
queues are empty so we know the box is seeing some accounting issue in this area:

Jul 26 09:15:27 kernel: ------------[ cut here ]------------
Jul 26 09:15:27 kernel: invalid inflight: 2 state 1 cwnd 68 mss 8988
Jul 26 09:15:27 kernel: WARNING: CPU: 16 PID: 0 at net/ipv4/tcp_output.c:2605 tcp_send_loss_probe+0x214/0x220
Jul 26 09:15:27 kernel: Modules linked in: vrf bridge stp llc vxlan ip6_udp_tunnel udp_tunnel nls_iso8859_1 nft_ct amd64_edac_mod edac_mce_amd kvm_amd kvm crct10dif_pclmul ghash_clmulni_intel aesni_intel crypto_simd cryptd glue_helper wmi_bmof ipmi_ssif joydev input_leds rndis_host cdc_ether usbnet mii ast drm_vram_helper ttm drm_kms_he>
Jul 26 09:15:27 kernel: CPU: 16 PID: 0 Comm: swapper/16 Not tainted 5.4.0-174-generic #193-Ubuntu
Jul 26 09:15:27 kernel: Hardware name: Supermicro SMC 2x26 os-gen8 64C NVME-Y 256G/H12SSW-NTR, BIOS 2.5.V1.2U.NVMe.UEFI 05/09/2023
Jul 26 09:15:27 kernel: RIP: 0010:tcp_send_loss_probe+0x214/0x220
Jul 26 09:15:27 kernel: Code: 08 26 01 00 75 e2 41 0f b6 54 24 12 41 8b 8c 24 c0 06 00 00 45 89 f0 48 c7 c7 e0 b4 20 a7 c6 05 8d 08 26 01 01 e8 4a c0 0f 00 <0f> 0b eb ba 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48 89 e5 41
Jul 26 09:15:27 kernel: RSP: 0018:ffffb7838088ce00 EFLAGS: 00010286
Jul 26 09:15:27 kernel: RAX: 0000000000000000 RBX: ffff9b84b5630430 RCX: 0000000000000006
Jul 26 09:15:27 kernel: RDX: 0000000000000007 RSI: 0000000000000096 RDI: ffff9b8e4621c8c0
Jul 26 09:15:27 kernel: RBP: ffffb7838088ce18 R08: 0000000000000927 R09: 0000000000000004
Jul 26 09:15:27 kernel: R10: 0000000000000000 R11: 0000000000000001 R12: ffff9b84b5630000
Jul 26 09:15:27 kernel: R13: 0000000000000000 R14: 000000000000231c R15: ffff9b84b5630430
Jul 26 09:15:27 kernel: FS: 0000000000000000(0000) GS:ffff9b8e46200000(0000) knlGS:0000000000000000
Jul 26 09:15:27 kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
Jul 26 09:15:27 kernel: CR2: 000056238cec2380 CR3: 0000003e49ede005 CR4: 0000000000760ee0
Jul 26 09:15:27 kernel: PKRU: 55555554
Jul 26 09:15:27 kernel: Call Trace:
Jul 26 09:15:27 kernel: <IRQ>
Jul 26 09:15:27 kernel: ? show_regs.cold+0x1a/0x1f
Jul 26 09:15:27 kernel: ? __warn+0x98/0xe0
Jul 26 09:15:27 kernel: ? tcp_send_loss_probe+0x214/0x220
Jul 26 09:15:27 kernel: ? report_bug+0xd1/0x100
Jul 26 09:15:27 kernel: ? do_error_trap+0x9b/0xc0
Jul 26 09:15:27 kernel: ? do_invalid_op+0x3c/0x50
Jul 26 09:15:27 kernel: ? tcp_send_loss_probe+0x214/0x220
Jul 26 09:15:27 kernel: ? invalid_op+0x1e/0x30
Jul 26 09:15:27 kernel: ? tcp_send_loss_probe+0x214/0x220
Jul 26 09:15:27 kernel: tcp_write_timer_handler+0x1b4/0x240
Jul 26 09:15:27 kernel: tcp_write_timer+0x9e/0xe0
Jul 26 09:15:27 kernel: ? tcp_write_timer_handler+0x240/0x240
Jul 26 09:15:27 kernel: call_timer_fn+0x32/0x130
Jul 26 09:15:27 kernel: __run_timers.part.0+0x180/0x280
Jul 26 09:15:27 kernel: ? timerqueue_add+0x9b/0xb0
Jul 26 09:15:27 kernel: ? enqueue_hrtimer+0x3d/0x90
Jul 26 09:15:27 kernel: ? do_error_trap+0x9b/0xc0
Jul 26 09:15:27 kernel: ? do_invalid_op+0x3c/0x50
Jul 26 09:15:27 kernel: ? tcp_send_loss_probe+0x214/0x220
Jul 26 09:15:27 kernel: ? invalid_op+0x1e/0x30
Jul 26 09:15:27 kernel: ? tcp_send_loss_probe+0x214/0x220
Jul 26 09:15:27 kernel: tcp_write_timer_handler+0x1b4/0x240
Jul 26 09:15:27 kernel: tcp_write_timer+0x9e/0xe0
Jul 26 09:15:27 kernel: ? tcp_write_timer_handler+0x240/0x240
Jul 26 09:15:27 kernel: call_timer_fn+0x32/0x130
Jul 26 09:15:27 kernel: __run_timers.part.0+0x180/0x280
Jul 26 09:15:27 kernel: ? timerqueue_add+0x9b/0xb0
Jul 26 09:15:27 kernel: ? enqueue_hrtimer+0x3d/0x90
Jul 26 09:15:27 kernel: ? recalibrate_cpu_khz+0x10/0x10
Jul 26 09:15:27 kernel: ? ktime_get+0x3e/0xa0
Jul 26 09:15:27 kernel: ? native_x2apic_icr_write+0x30/0x30
Jul 26 09:15:27 kernel: run_timer_softirq+0x2a/0x50
Jul 26 09:15:27 kernel: __do_softirq+0xd1/0x2c1
Jul 26 09:15:27 kernel: irq_exit+0xae/0xb0
Jul 26 09:15:27 kernel: smp_apic_timer_interrupt+0x7b/0x140
Jul 26 09:15:27 kernel: apic_timer_interrupt+0xf/0x20
Jul 26 09:15:27 kernel: </IRQ>
Jul 26 09:15:27 kernel: RIP: 0010:native_safe_halt+0xe/0x10
Jul 26 09:15:27 kernel: Code: 7b ff ff ff eb bd 90 90 90 90 90 90 e9 07 00 00 00 0f 00 2d 36 2c 50 00 f4 c3 66 90 e9 07 00 00 00 0f 00 2d 26 2c 50 00 fb f4 <c3> 90 0f 1f 44 00 00 55 48 89 e5 41 55 41 54 53 e8 dd 5e 61 ff 65
Jul 26 09:15:27 kernel: RSP: 0018:ffffb783801cfe70 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
Jul 26 09:15:27 kernel: RAX: ffffffffa6908b20 RBX: 0000000000000010 RCX: 0000000000000001
Jul 26 09:15:27 kernel: RDX: 000000006fc0c97e RSI: 0000000000000082 RDI: 0000000000000082
Jul 26 09:15:27 kernel: RBP: ffffb783801cfe90 R08: 0000000000000000 R09: 0000000000000225
Jul 26 09:15:27 kernel: R10: 0000000000100000 R11: 0000000000000000 R12: 0000000000000010
Jul 26 09:15:27 kernel: R13: ffff9b8e390b0000 R14: 0000000000000000 R15: 0000000000000000
Jul 26 09:15:27 kernel: ? __cpuidle_text_start+0x8/0x8
Jul 26 09:15:27 kernel: ? default_idle+0x20/0x140
Jul 26 09:15:27 kernel: arch_cpu_idle+0x15/0x20
Jul 26 09:15:27 kernel: default_idle_call+0x23/0x30
Jul 26 09:15:27 kernel: do_idle+0x1fb/0x270
Jul 26 09:15:27 kernel: cpu_startup_entry+0x20/0x30
Jul 26 09:15:27 kernel: start_secondary+0x178/0x1d0
Jul 26 09:15:27 kernel: secondary_startup_64+0xa4/0xb0
Jul 26 09:15:27 kernel: ---[ end trace e7ac822987e33be1 ]---

The NULL ptr deref is coming from tcp_rto_delta_us() attempting to pull an skb
off the head of the retransmit queue and then dereferencing that skb to get the
skb_mstamp_ns value via tcp_skb_timestamp_us(skb).

The crash is the same one that was reported a # of years ago here:
https://lore.kernel.org/netdev/86c0f836-9a7c-438b-d81a-839be45f1f58@gmail.com/T/#t

and the kernel we're running has the fix which was added to resolve this issue.

Unfortunately we've been unsuccessful so far in reproducing this problem in the
lab and do not have the luxury of pushing out a new kernel to try and test if
newer kernels resolve this issue at the moment. I realize this is a report
against both an Ubuntu kernel and also an older 5.4 kernel. I have reported this
issue to Ubuntu here: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2077657
however I feel like since this issue has possibly cropped up again it makes
sense to build in some protection in this path (even on the latest kernel
versions) since the code in question just blindly assumes there's a valid skb
without testing if it's NULL b/f it looks at the timestamp.

Given we have seen crashes in this path before and now this case it seems like
we should protect ourselves for when packets_out accounting is incorrect.
While we should fix that root cause we should also just make sure the skb
is not NULL before dereferencing it. Also add a warn once here to capture
some information if/when the problem case is hit again.

Fixes: e1a10ef ("tcp: introduce tcp_rto_delta_us() helper for xmit timer fix")
Signed-off-by: Josh Hunt <johunt@akamai.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
matttbe pushed a commit that referenced this issue Sep 27, 2024
…git/netfilter/nf

Pablo Neira Ayuso says:

====================
Netfilter fixes for net

v2: with kdoc fixes per Paolo Abeni.

The following patchset contains Netfilter fixes for net:

Patch #1 and #2 handle an esoteric scenario: Given two tasks sending UDP
packets to one another, two packets of the same flow in each direction
handled by different CPUs that result in two conntrack objects in NEW
state, where reply packet loses race. Then, patch #3 adds a testcase for
this scenario. Series from Florian Westphal.

1) NAT engine can falsely detect a port collision if it happens to pick
   up a reply packet as NEW rather than ESTABLISHED. Add extra code to
   detect this and suppress port reallocation in this case.

2) To complete the clash resolution in the reply direction, extend conntrack
   logic to detect clashing conntrack in the reply direction to existing entry.

3) Adds a test case.

Then, an assorted list of fixes follow:

4) Add a selftest for tproxy, from Antonio Ojea.

5) Guard ctnetlink_*_size() functions under
   #if defined(CONFIG_NETFILTER_NETLINK_GLUE_CT) || defined(CONFIG_NF_CONNTRACK_EVENTS)
   From Andy Shevchenko.

6) Use -m socket --transparent in iptables tproxy documentation.
   From XIE Zhibang.

7) Call kfree_rcu() when releasing flowtable hooks to address race with
   netlink dump path, from Phil Sutter.

8) Fix compilation warning in nf_reject with CONFIG_BRIDGE_NETFILTER=n.
   From Simon Horman.

9) Guard ctnetlink_label_size() under CONFIG_NF_CONNTRACK_EVENTS which
   is its only user, to address a compilation warning. From Simon Horman.

10) Use rcu-protected list iteration over basechain hooks from netlink
    dump path.

11) Fix memcg for nf_tables, use GFP_KERNEL_ACCOUNT is not complete.

12) Remove old nfqueue conntrack clash resolution. Instead trying to
    use same destination address consistently which requires double DNAT,
    use the existing clash resolution which allows clashing packets
    go through with different destination. Antonio Ojea originally
    reported an issue from the postrouting chain, I proposed a fix:
    https://lore.kernel.org/netfilter-devel/ZuwSwAqKgCB2a51-@calendula/T/
    which he reported it did not work for him.

13) Adds a selftest for patch 12.

14) Fixes ipvs.sh selftest.

netfilter pull request 24-09-26

* tag 'nf-24-09-26' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
  selftests: netfilter: Avoid hanging ipvs.sh
  kselftest: add test for nfqueue induced conntrack race
  netfilter: nfnetlink_queue: remove old clash resolution logic
  netfilter: nf_tables: missing objects with no memcg accounting
  netfilter: nf_tables: use rcu chain hook list iterator from netlink dump path
  netfilter: ctnetlink: compile ctnetlink_label_size with CONFIG_NF_CONNTRACK_EVENTS
  netfilter: nf_reject: Fix build warning when CONFIG_BRIDGE_NETFILTER=n
  netfilter: nf_tables: Keep deleted flowtable hooks until after RCU
  docs: tproxy: ignore non-transparent sockets in iptables
  netfilter: ctnetlink: Guard possible unused functions
  selftests: netfilter: nft_tproxy.sh: add tcp tests
  selftests: netfilter: add reverse-clash resolution test case
  netfilter: conntrack: add clash resolution for reverse collisions
  netfilter: nf_nat: don't try nat source port reallocation for reverse dir clash
====================

Link: https://patch.msgid.link/20240926110717.102194-1-pablo@netfilter.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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