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arm/aspeed_defconfig: Add required options to boot with systemd #2

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merged 1 commit into from
Oct 13, 2015

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apopple added a commit that referenced this pull request Oct 13, 2015
arm/aspeed_defconfig: Add required options to boot with systemd
@apopple apopple merged commit abab3a8 into openbmc:dev Oct 13, 2015
@@ -148,7 +151,7 @@ CONFIG_USB_STORAGE=y
CONFIG_USB_SERIAL=y
CONFIG_USB_SERIAL_GENERIC=y
CONFIG_USB_GADGET=y
CONFIG_USB_G_SERIAL=y
CONFIG_USB_G_SERIAL=m
CONFIG_MMC=y
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What's up with this change?

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Hey,

On Mon, 12 Oct 2015 23:06:54 Joel Stanley wrote:

@@ -148,7 +151,7 @@ CONFIG_USB_STORAGE=y
CONFIG_USB_SERIAL=y
CONFIG_USB_SERIAL_GENERIC=y
CONFIG_USB_GADGET=y
-CONFIG_USB_G_SERIAL=y
+CONFIG_USB_G_SERIAL=m
CONFIG_MMC=y

What's up with this change?

Just talked Cyril ... no reason really. Apparently the kernel defconfig generator made the change. Is this something we care about?


Reply to this email directly or view it on GitHub:
https://github.com/openbmc/linux/pull/2/files#r41829799

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On Tue, Oct 13, 2015 at 4:42 PM, apopple notifications@github.com wrote:

Just talked Cyril ... no reason really. Apparently the kernel defconfig generator made the change. Is this something we care about?

Not really, it's just for the cases where we're netbooting kernels we
will be missing any modules, so we want everything to be either =y or
=n. I don't think anyone is doing usb stuff yet.

shenki pushed a commit that referenced this pull request Nov 13, 2015
Kernel testing triggered this warning:

| WARNING: CPU: 0 PID: 13 at kernel/sched/core.c:1156 do_set_cpus_allowed+0x7e/0x80()
| Modules linked in:
| CPU: 0 PID: 13 Comm: migration/0 Not tainted 4.2.0-rc1-00049-g25834c7 #2
| Call Trace:
|   dump_stack+0x4b/0x75
|   warn_slowpath_common+0x8b/0xc0
|   warn_slowpath_null+0x22/0x30
|   do_set_cpus_allowed+0x7e/0x80
|   cpuset_cpus_allowed_fallback+0x7c/0x170
|   select_fallback_rq+0x221/0x280
|   migration_call+0xe3/0x250
|   notifier_call_chain+0x53/0x70
|   __raw_notifier_call_chain+0x1e/0x30
|   cpu_notify+0x28/0x50
|   take_cpu_down+0x22/0x40
|   multi_cpu_stop+0xd5/0x140
|   cpu_stopper_thread+0xbc/0x170
|   smpboot_thread_fn+0x174/0x2f0
|   kthread+0xc4/0xe0
|   ret_from_kernel_thread+0x21/0x30

As Peterz pointed out:

| So the normal rules for changing task_struct::cpus_allowed are holding
| both pi_lock and rq->lock, such that holding either stabilizes the mask.
|
| This is so that wakeup can happen without rq->lock and load-balance
| without pi_lock.
|
| From this we already get the relaxation that we can omit acquiring
| rq->lock if the task is not on the rq, because in that case
| load-balancing will not apply to it.
|
| ** these are the rules currently tested in do_set_cpus_allowed() **
|
| Now, since __set_cpus_allowed_ptr() uses task_rq_lock() which
| unconditionally acquires both locks, we could get away with holding just
| rq->lock when on_rq for modification because that'd still exclude
| __set_cpus_allowed_ptr(), it would also work against
| __kthread_bind_mask() because that assumes !on_rq.
|
| That said, this is all somewhat fragile.
|
| Now, I don't think dropping rq->lock is quite as disastrous as it
| usually is because !cpu_active at this point, which means load-balance
| will not interfere, but that too is somewhat fragile.
|
| So we end up with a choice of two fragile..

This patch fixes it by following the rules for changing
task_struct::cpus_allowed with both pi_lock and rq->lock held.

Reported-by: kernel test robot <ying.huang@intel.com>
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
[ Modified changelog and patch. ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
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/BLU436-SMTP1660820490DE202E3934ED3806E0@phx.gbl
Signed-off-by: Ingo Molnar <mingo@kernel.org>
shenki pushed a commit that referenced this pull request Nov 13, 2015
The renesas-irqc interrupt controller is cascaded to the GIC. Hence when
propagating wake-up settings to its parent interrupt controller, the
following lockdep warning is printed:

    =============================================
    [ INFO: possible recursive locking detected ]
    4.2.0-ape6evm-10725-g50fcd7643c034198 torvalds#280 Not tainted
    ---------------------------------------------
    s2ram/1072 is trying to acquire lock:
    (&irq_desc_lock_class){-.-...}, at: [<c008d3fc>] __irq_get_desc_lock+0x58/0x98

    but task is already holding lock:
    (&irq_desc_lock_class){-.-...}, at: [<c008d3fc>] __irq_get_desc_lock+0x58/0x98

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

	  CPU0
	  ----
     lock(&irq_desc_lock_class);
     lock(&irq_desc_lock_class);

    *** DEADLOCK ***

    May be due to missing lock nesting notation

    6 locks held by s2ram/1072:
    #0:  (sb_writers#7){.+.+.+}, at: [<c012eb14>] __sb_start_write+0xa0/0xa8
    #1:  (&of->mutex){+.+.+.}, at: [<c019396c>] kernfs_fop_write+0x4c/0x1bc
    #2:  (s_active#24){.+.+.+}, at: [<c0193974>] kernfs_fop_write+0x54/0x1bc
    #3:  (pm_mutex){+.+.+.}, at: [<c008213c>] pm_suspend+0x10c/0x510
    #4:  (&dev->mutex){......}, at: [<c02af3c4>] __device_suspend+0xdc/0x2cc
    #5:  (&irq_desc_lock_class){-.-...}, at: [<c008d3fc>] __irq_get_desc_lock+0x58/0x98

    stack backtrace:
    CPU: 0 PID: 1072 Comm: s2ram Not tainted 4.2.0-ape6evm-10725-g50fcd7643c034198 torvalds#280
    Hardware name: Generic R8A73A4 (Flattened Device Tree)
    [<c0018078>] (unwind_backtrace) from [<c00144f0>] (show_stack+0x10/0x14)
    [<c00144f0>] (show_stack) from [<c0451f14>] (dump_stack+0x88/0x98)
    [<c0451f14>] (dump_stack) from [<c007b29c>] (__lock_acquire+0x15cc/0x20e4)
    [<c007b29c>] (__lock_acquire) from [<c007c6e0>] (lock_acquire+0xac/0x12c)
    [<c007c6e0>] (lock_acquire) from [<c0457c00>] (_raw_spin_lock_irqsave+0x40/0x54)
    [<c0457c00>] (_raw_spin_lock_irqsave) from [<c008d3fc>] (__irq_get_desc_lock+0x58/0x98)
    [<c008d3fc>] (__irq_get_desc_lock) from [<c008ebbc>] (irq_set_irq_wake+0x20/0xf8)
    [<c008ebbc>] (irq_set_irq_wake) from [<c0260770>] (irqc_irq_set_wake+0x20/0x4c)
    [<c0260770>] (irqc_irq_set_wake) from [<c008ec28>] (irq_set_irq_wake+0x8c/0xf8)
    [<c008ec28>] (irq_set_irq_wake) from [<c02cb8c0>] (gpio_keys_suspend+0x74/0xc0)
    [<c02cb8c0>] (gpio_keys_suspend) from [<c02ae8cc>] (dpm_run_callback+0x54/0x124)

Avoid this false positive by using a separate lockdep class for IRQC
interrupts.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/1441798974-25716-2-git-send-email-geert%2Brenesas@glider.be
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
shenki pushed a commit that referenced this pull request Nov 13, 2015
The renesas-intc-irqpin interrupt controller is cascaded to the GIC.
Hence when propagating wake-up settings to its parent interrupt
controller, the following lockdep warning is printed:

    =============================================
    [ INFO: possible recursive locking detected ]
    4.2.0-armadillo-10725-g50fcd7643c034198 torvalds#781 Not tainted
    ---------------------------------------------
    s2ram/1179 is trying to acquire lock:
    (&irq_desc_lock_class){-.-...}, at: [<c005bb54>] __irq_get_desc_lock+0x78/0x94

    but task is already holding lock:
    (&irq_desc_lock_class){-.-...}, at: [<c005bb54>] __irq_get_desc_lock+0x78/0x94

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

	  CPU0
	  ----
     lock(&irq_desc_lock_class);
     lock(&irq_desc_lock_class);

    *** DEADLOCK ***

    May be due to missing lock nesting notation

    7 locks held by s2ram/1179:
    #0:  (sb_writers#7){.+.+.+}, at: [<c00c9708>] __sb_start_write+0x64/0xb8
    #1:  (&of->mutex){+.+.+.}, at: [<c0125a00>] kernfs_fop_write+0x78/0x1a0
    #2:  (s_active#23){.+.+.+}, at: [<c0125a08>] kernfs_fop_write+0x80/0x1a0
    #3:  (autosleep_lock){+.+.+.}, at: [<c0058244>] pm_autosleep_lock+0x18/0x20
    #4:  (pm_mutex){+.+.+.}, at: [<c0057e50>] pm_suspend+0x54/0x248
    #5:  (&dev->mutex){......}, at: [<c0243a20>] __device_suspend+0xdc/0x240
    #6:  (&irq_desc_lock_class){-.-...}, at: [<c005bb54>] __irq_get_desc_lock+0x78/0x94

    stack backtrace:
    CPU: 0 PID: 1179 Comm: s2ram Not tainted 4.2.0-armadillo-10725-g50fcd7643c034198

    Hardware name: Generic R8A7740 (Flattened Device Tree)
    [<c00129f4>] (dump_backtrace) from [<c0012bec>] (show_stack+0x18/0x1c)
    [<c0012bd4>] (show_stack) from [<c03f5d94>] (dump_stack+0x20/0x28)
    [<c03f5d74>] (dump_stack) from [<c00514d4>] (__lock_acquire+0x67c/0x1b88)
    [<c0050e58>] (__lock_acquire) from [<c0052df8>] (lock_acquire+0x9c/0xbc)
    [<c0052d5c>] (lock_acquire) from [<c03fb068>] (_raw_spin_lock_irqsave+0x44/0x58)
    [<c03fb024>] (_raw_spin_lock_irqsave) from [<c005bb54>] (__irq_get_desc_lock+0x78/0x94
    [<c005badc>] (__irq_get_desc_lock) from [<c005c3d8>] (irq_set_irq_wake+0x28/0x100)
    [<c005c3b0>] (irq_set_irq_wake) from [<c01e50d0>] (intc_irqpin_irq_set_wake+0x24/0x4c)
    [<c01e50ac>] (intc_irqpin_irq_set_wake) from [<c005c17c>] (set_irq_wake_real+0x3c/0x50
    [<c005c140>] (set_irq_wake_real) from [<c005c414>] (irq_set_irq_wake+0x64/0x100)
    [<c005c3b0>] (irq_set_irq_wake) from [<c02a19b4>] (gpio_keys_suspend+0x60/0xa0)
    [<c02a1954>] (gpio_keys_suspend) from [<c023b750>] (platform_pm_suspend+0x3c/0x5c)

Avoid this false positive by using a separate lockdep class for INTC
External IRQ Pin interrupts.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/1441798974-25716-3-git-send-email-geert%2Brenesas@glider.be
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
shenki pushed a commit that referenced this pull request Nov 13, 2015
The OPP list needs to be protected against concurrent accesses. Using
simple RCU read locks does the trick and gets rid of the following
lockdep warning:

	===============================
	[ INFO: suspicious RCU usage. ]
	4.2.0-next-20150908 #1 Not tainted
	-------------------------------
	drivers/base/power/opp.c:460 Missing rcu_read_lock() or dev_opp_list_lock protection!

	other info that might help us debug this:

	rcu_scheduler_active = 1, debug_locks = 0
	4 locks held by kworker/u8:0/6:
	 #0:  ("%s""deferwq"){++++.+}, at: [<c0040d8c>] process_one_work+0x118/0x4bc
	 #1:  (deferred_probe_work){+.+.+.}, at: [<c0040d8c>] process_one_work+0x118/0x4bc
	 #2:  (&dev->mutex){......}, at: [<c03b8194>] __device_attach+0x20/0x118
	 #3:  (prepare_lock){+.+...}, at: [<c054bc08>] clk_prepare_lock+0x10/0xf8

	stack backtrace:
	CPU: 2 PID: 6 Comm: kworker/u8:0 Not tainted 4.2.0-next-20150908 #1
	Hardware name: NVIDIA Tegra SoC (Flattened Device Tree)
	Workqueue: deferwq deferred_probe_work_func
	[<c001802c>] (unwind_backtrace) from [<c00135a4>] (show_stack+0x10/0x14)
	[<c00135a4>] (show_stack) from [<c02a8418>] (dump_stack+0x94/0xd4)
	[<c02a8418>] (dump_stack) from [<c03c6f6c>] (dev_pm_opp_find_freq_ceil+0x108/0x114)
	[<c03c6f6c>] (dev_pm_opp_find_freq_ceil) from [<c0551a3c>] (dfll_calculate_rate_request+0xb8/0x170)
	[<c0551a3c>] (dfll_calculate_rate_request) from [<c0551b10>] (dfll_clk_round_rate+0x1c/0x2c)
	[<c0551b10>] (dfll_clk_round_rate) from [<c054de2c>] (clk_calc_new_rates+0x1b8/0x228)
	[<c054de2c>] (clk_calc_new_rates) from [<c054e44c>] (clk_core_set_rate_nolock+0x44/0xac)
	[<c054e44c>] (clk_core_set_rate_nolock) from [<c054e4d8>] (clk_set_rate+0x24/0x34)
	[<c054e4d8>] (clk_set_rate) from [<c0512460>] (tegra124_cpufreq_probe+0x120/0x230)
	[<c0512460>] (tegra124_cpufreq_probe) from [<c03b9cbc>] (platform_drv_probe+0x44/0xac)
	[<c03b9cbc>] (platform_drv_probe) from [<c03b84c8>] (driver_probe_device+0x218/0x304)
	[<c03b84c8>] (driver_probe_device) from [<c03b69b0>] (bus_for_each_drv+0x60/0x94)
	[<c03b69b0>] (bus_for_each_drv) from [<c03b8228>] (__device_attach+0xb4/0x118)
	ata1: SATA link down (SStatus 0 SControl 300)
	[<c03b8228>] (__device_attach) from [<c03b77c8>] (bus_probe_device+0x88/0x90)
	[<c03b77c8>] (bus_probe_device) from [<c03b7be8>] (deferred_probe_work_func+0x58/0x8c)
	[<c03b7be8>] (deferred_probe_work_func) from [<c0040dfc>] (process_one_work+0x188/0x4bc)
	[<c0040dfc>] (process_one_work) from [<c004117c>] (worker_thread+0x4c/0x4f4)
	[<c004117c>] (worker_thread) from [<c0047230>] (kthread+0xe4/0xf8)
	[<c0047230>] (kthread) from [<c000f7d0>] (ret_from_fork+0x14/0x24)

Signed-off-by: Thierry Reding <treding@nvidia.com>
Fixes: c4fe70a ("clk: tegra: Add closed loop support for the DFLL")
[vince.h@nvidia.com: Unlock rcu on error path]
Signed-off-by: Vince Hsu <vince.h@nvidia.com>
[sboyd@codeaurora.org: Dropped second hunk that nested the rcu
read lock unnecessarily]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
shenki pushed a commit that referenced this pull request Nov 13, 2015
…t initialized.

In case something goes wrong with power well initialization we were calling
intel_prepare_ddi during boot while encoder list isnt't initilized.

[    9.618747] i915 0000:00:02.0: Invalid ROM contents
[    9.631446] [drm] failed to find VBIOS tables
[    9.720036] BUG: unable to handle kernel NULL pointer dereference at 00000000
00000058
[    9.721986] IP: [<ffffffffa014eb72>] ddi_get_encoder_port+0x82/0x190 [i915]
[    9.723736] PGD 0
[    9.724286] Oops: 0000 [#1] PREEMPT SMP
[    9.725386] Modules linked in: intel_powerclamp snd_hda_intel(+) coretemp crc
32c_intel snd_hda_codec snd_hda_core serio_raw snd_pcm snd_timer i915(+) parport
_pc parport pinctrl_sunrisepoint pinctrl_intel nfsd nfs_acl
[    9.730635] CPU: 0 PID: 497 Comm: systemd-udevd Not tainted 4.3.0-rc2-eywa-10
967-g72de2cfd-dirty #2
[    9.732785] Hardware name: Intel Corporation Cannonlake Client platform/Skyla
ke DT DDR4 RVP8, BIOS CNLSE2R1.R00.X021.B00.1508040310 08/04/2015
[    9.735785] task: ffff88008a704700 ti: ffff88016a1ac000 task.ti: ffff88016a1a
c000
[    9.737584] RIP: 0010:[<ffffffffa014eb72>]  [<ffffffffa014eb72>] ddi_get_enco
der_port+0x82/0x190 [i915]
[    9.739934] RSP: 0000:ffff88016a1af710  EFLAGS: 00010296
[    9.741184] RAX: 000000000000004e RBX: ffff88008a9edc98 RCX: 0000000000000001
[    9.742934] RDX: 000000000000004e RSI: ffffffff81fc1e82 RDI: 00000000ffffffff
[    9.744634] RBP: ffff88016a1af730 R08: 0000000000000000 R09: 0000000000000578
[    9.746333] R10: 0000000000001065 R11: 0000000000000578 R12: fffffffffffffff8
[    9.748033] R13: ffff88016a1af7a8 R14: ffff88016a1af794 R15: 0000000000000000
[    9.749733] FS:  00007eff2e1e07c0(0000) GS:ffff88016fc00000(0000) knlGS:00000
00000000000
[    9.751683] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    9.753083] CR2: 0000000000000058 CR3: 000000016922b000 CR4: 00000000003406f0
[    9.754782] Stack:
[    9.755332]  ffff88008a9edc98 ffff88008a9ed800 ffffffffa01d07b0 00000000fffb9
09e
[    9.757232]  ffff88016a1af7d8 ffffffffa0154ea7 0000000000000246 ffff88016a370
080
[    9.759182]  ffff88016a370080 ffff88008a9ed800 0000000000000246 ffff88008a9ed
c98
[    9.761132] Call Trace:
[    9.761782]  [<ffffffffa0154ea7>] intel_prepare_ddi+0x67/0x860 [i915]
[    9.763332]  [<ffffffff81a56996>] ? _raw_spin_unlock_irqrestore+0x26/0x40
[    9.765031]  [<ffffffffa00fad01>] ? gen9_read32+0x141/0x360 [i915]
[    9.766531]  [<ffffffffa00b43e1>] skl_set_power_well+0x431/0xa80 [i915]
[    9.768181]  [<ffffffffa00b4a63>] skl_power_well_enable+0x13/0x20 [i915]
[    9.769781]  [<ffffffffa00b2188>] intel_power_well_enable+0x28/0x50 [i915]
[    9.771481]  [<ffffffffa00b4d52>] intel_display_power_get+0x92/0xc0 [i915]
[    9.773180]  [<ffffffffa00b4fcb>] intel_display_set_init_power+0x3b/0x40 [i91
5]
[    9.774980]  [<ffffffffa00b5170>] intel_power_domains_init_hw+0x120/0x520 [i9
15]
[    9.776780]  [<ffffffffa0194c61>] i915_driver_load+0xb21/0xf40 [i915]

So let's protect this case.

My first attempt was to remove the intel_prepare_ddi, but Daniel had pointed out
this is really needed to restore those registers values. And Imre pointed out
that this case was without the flag protection and this was actually where things
were going bad. So I've just checked and this indeed solves my issue.

The regressing intel_prepare_ddi call was added in

commit 1d2b952
Author: Damien Lespiau <damien.lespiau@intel.com>
Date:   Fri Mar 6 18:50:53 2015 +0000

    drm/i915/skl: Restore the DDI translation tables when enabling PW1

Cc: Imre Deak <imre.deak@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
[Jani: regression reference]
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
shenki pushed a commit that referenced this pull request Nov 13, 2015
Dmitry Vyukov reported the following using trinity and the memory
error detector AddressSanitizer
(https://code.google.com/p/address-sanitizer/wiki/AddressSanitizerForKernel).

[ 124.575597] ERROR: AddressSanitizer: heap-buffer-overflow on
address ffff88002e280000
[ 124.576801] ffff88002e280000 is located 131938492886538 bytes to
the left of 28857600-byte region [ffffffff81282e0a, ffffffff82e0830a)
[ 124.578633] Accessed by thread T10915:
[ 124.579295] inlined in describe_heap_address
./arch/x86/mm/asan/report.c:164
[ 124.579295] #0 ffffffff810dd277 in asan_report_error
./arch/x86/mm/asan/report.c:278
[ 124.580137] #1 ffffffff810dc6a0 in asan_check_region
./arch/x86/mm/asan/asan.c:37
[ 124.581050] #2 ffffffff810dd423 in __tsan_read8 ??:0
[ 124.581893] #3 ffffffff8107c093 in get_wchan
./arch/x86/kernel/process_64.c:444

The address checks in the 64bit implementation of get_wchan() are
wrong in several ways:

 - The lower bound of the stack is not the start of the stack
   page. It's the start of the stack page plus sizeof (struct
   thread_info)

 - The upper bound must be:

       top_of_stack - TOP_OF_KERNEL_STACK_PADDING - 2 * sizeof(unsigned long).

   The 2 * sizeof(unsigned long) is required because the stack pointer
   points at the frame pointer. The layout on the stack is: ... IP FP
   ... IP FP. So we need to make sure that both IP and FP are in the
   bounds.

Fix the bound checks and get rid of the mix of numeric constants, u64
and unsigned long. Making all unsigned long allows us to use the same
function for 32bit as well.

Use READ_ONCE() when accessing the stack. This does not prevent a
concurrent wakeup of the task and the stack changing, but at least it
avoids TOCTOU.

Also check task state at the end of the loop. Again that does not
prevent concurrent changes, but it avoids walking for nothing.

Add proper comments while at it.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Based-on-patch-from: Wolfram Gloger <wmglo@dent.med.uni-muenchen.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@alien8.de>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Kostya Serebryany <kcc@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: kasan-dev <kasan-dev@googlegroups.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Wolfram Gloger <wmglo@dent.med.uni-muenchen.de>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20150930083302.694788319@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
shenki pushed a commit that referenced this pull request Nov 13, 2015
Commit 1a3d595 ("MIPS: Tidy up FPU context switching") removed FP
context saving from the asm-written resume function in favour of reusing
existing code to perform the same task. However it only removed the FP
context saving code from the r4k_switch.S implementation of resume.
Octeon uses its own implementation in octeon_switch.S, so remove FP
context saving there too in order to prevent attempting to save context
twice. That formerly led to an exception from the second save as follows
because the FPU had already been disabled by the first save:

    do_cpu invoked from kernel context![#1]:
    CPU: 0 PID: 2 Comm: kthreadd Not tainted 4.3.0-rc2-dirty #2
    task: 800000041f84a008 ti: 800000041f864000 task.ti: 800000041f864000
    $ 0   : 0000000000000000 0000000010008ce1 0000000000100000 ffffffffbfffffff
    $ 4   : 800000041f84a008 800000041f84ac08 800000041f84c000 0000000000000004
    $ 8   : 0000000000000001 0000000000000000 0000000000000000 0000000000000001
    $12   : 0000000010008ce3 0000000000119c60 0000000000000036 800000041f864000
    $16   : 800000041f84ac08 800000000792ce80 800000041f84a008 ffffffff81758b00
    $20   : 0000000000000000 ffffffff8175ae50 0000000000000000 ffffffff8176c740
    $24   : 0000000000000006 ffffffff81170300
    $28   : 800000041f864000 800000041f867d90 0000000000000000 ffffffff815f3fa0
    Hi    : 0000000000fa8257
    Lo    : ffffffffe15cfc00
    epc   : ffffffff8112821c resume+0x9c/0x200
    ra    : ffffffff815f3fa0 __schedule+0x3f0/0x7d8
    Status: 10008ce2        KX SX UX KERNEL EXL
    Cause : 1080002c (ExcCode 0b)
    PrId  : 000d0601 (Cavium Octeon+)
    Modules linked in:
    Process kthreadd (pid: 2, threadinfo=800000041f864000, task=800000041f84a008, tls=0000000000000000)
    Stack : ffffffff81604218 ffffffff815f7e08 800000041f84a008 ffffffff811681b0
              800000041f84a008 ffffffff817e9878 0000000000000000 ffffffff81770000
              ffffffff81768340 ffffffff81161398 0000000000000001 0000000000000000
              0000000000000000 ffffffff815f4424 0000000000000000 ffffffff81161d68
              ffffffff81161be8 0000000000000000 0000000000000000 0000000000000000
              0000000000000000 0000000000000000 0000000000000000 ffffffff8111e16c
              0000000000000000 0000000000000000 0000000000000000 0000000000000000
              0000000000000000 0000000000000000 0000000000000000 0000000000000000
              0000000000000000 0000000000000000 0000000000000000 0000000000000000
              0000000000000000 0000000000000000 0000000000000000 0000000000000000
              ...
    Call Trace:
    [<ffffffff8112821c>] resume+0x9c/0x200
    [<ffffffff815f3fa0>] __schedule+0x3f0/0x7d8
    [<ffffffff815f4424>] schedule+0x34/0x98
    [<ffffffff81161d68>] kthreadd+0x180/0x198
    [<ffffffff8111e16c>] ret_from_kernel_thread+0x14/0x1c

Tested using cavium_octeon_defconfig on an EdgeRouter Lite.

Fixes: 1a3d595 ("MIPS: Tidy up FPU context switching")
Reported-by: Aaro Koskinen <aaro.koskinen@nokia.com>
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Aleksey Makarov <aleksey.makarov@auriga.com>
Cc: linux-kernel@vger.kernel.org
Cc: Chandrakala Chavva <cchavva@caviumnetworks.com>
Cc: David Daney <david.daney@cavium.com>
Cc: Leonid Rosenboim <lrosenboim@caviumnetworks.com>
Patchwork: https://patchwork.linux-mips.org/patch/11166/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
shenki pushed a commit that referenced this pull request Nov 13, 2015
My colleague ran into a program stall on a x86_64 server, where
n_tty_read() was waiting for data even if there was data in the buffer
in the pty.  kernel stack for the stuck process looks like below.
 #0 [ffff88303d107b58] __schedule at ffffffff815c4b20
 #1 [ffff88303d107bd0] schedule at ffffffff815c513e
 #2 [ffff88303d107bf0] schedule_timeout at ffffffff815c7818
 #3 [ffff88303d107ca0] wait_woken at ffffffff81096bd2
 #4 [ffff88303d107ce0] n_tty_read at ffffffff8136fa23
 #5 [ffff88303d107dd0] tty_read at ffffffff81368013
 #6 [ffff88303d107e20] __vfs_read at ffffffff811a3704
 #7 [ffff88303d107ec0] vfs_read at ffffffff811a3a57
 #8 [ffff88303d107f00] sys_read at ffffffff811a4306
 #9 [ffff88303d107f50] entry_SYSCALL_64_fastpath at ffffffff815c86d7

There seems to be two problems causing this issue.

First, in drivers/tty/n_tty.c, __receive_buf() stores the data and
updates ldata->commit_head using smp_store_release() and then checks
the wait queue using waitqueue_active().  However, since there is no
memory barrier, __receive_buf() could return without calling
wake_up_interactive_poll(), and at the same time, n_tty_read() could
start to wait in wait_woken() as in the following chart.

        __receive_buf()                         n_tty_read()
------------------------------------------------------------------------
if (waitqueue_active(&tty->read_wait))
/* Memory operations issued after the
   RELEASE may be completed before the
   RELEASE operation has completed */
                                        add_wait_queue(&tty->read_wait, &wait);
                                        ...
                                        if (!input_available_p(tty, 0)) {
smp_store_release(&ldata->commit_head,
                  ldata->read_head);
                                        ...
                                        timeout = wait_woken(&wait,
                                          TASK_INTERRUPTIBLE, timeout);
------------------------------------------------------------------------

The second problem is that n_tty_read() also lacks a memory barrier
call and could also cause __receive_buf() to return without calling
wake_up_interactive_poll(), and n_tty_read() to wait in wait_woken()
as in the chart below.

        __receive_buf()                         n_tty_read()
------------------------------------------------------------------------
                                        spin_lock_irqsave(&q->lock, flags);
                                        /* from add_wait_queue() */
                                        ...
                                        if (!input_available_p(tty, 0)) {
                                        /* Memory operations issued after the
                                           RELEASE may be completed before the
                                           RELEASE operation has completed */
smp_store_release(&ldata->commit_head,
                  ldata->read_head);
if (waitqueue_active(&tty->read_wait))
                                        __add_wait_queue(q, wait);
                                        spin_unlock_irqrestore(&q->lock,flags);
                                        /* from add_wait_queue() */
                                        ...
                                        timeout = wait_woken(&wait,
                                          TASK_INTERRUPTIBLE, timeout);
------------------------------------------------------------------------

There are also other places in drivers/tty/n_tty.c which have similar
calls to waitqueue_active(), so instead of adding many memory barrier
calls, this patch simply removes the call to waitqueue_active(),
leaving just wake_up*() behind.

This fixes both problems because, even though the memory access before
or after the spinlocks in both wake_up*() and add_wait_queue() can
sneak into the critical section, it cannot go past it and the critical
section assures that they will be serialized (please see "INTER-CPU
ACQUIRING BARRIER EFFECTS" in Documentation/memory-barriers.txt for a
better explanation).  Moreover, the resulting code is much simpler.

Latency measurement using a ping-pong test over a pty doesn't show any
visible performance drop.

Signed-off-by: Kosuke Tatsukawa <tatsu@ab.jp.nec.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
shenki pushed a commit that referenced this pull request Nov 13, 2015
When running kprobe test on arm64 rt kernel, it reports the below warning:

root@qemu7:~# modprobe kprobe_example
BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:917
in_atomic(): 0, irqs_disabled(): 128, pid: 484, name: modprobe
CPU: 0 PID: 484 Comm: modprobe Not tainted 4.1.6-rt5 #2
Hardware name: linux,dummy-virt (DT)
Call trace:
[<ffffffc0000891b8>] dump_backtrace+0x0/0x128
[<ffffffc000089300>] show_stack+0x20/0x30
[<ffffffc00061dae8>] dump_stack+0x1c/0x28
[<ffffffc0000bbad0>] ___might_sleep+0x120/0x198
[<ffffffc0006223e8>] rt_spin_lock+0x28/0x40
[<ffffffc000622b30>] __aarch64_insn_write+0x28/0x78
[<ffffffc000622e48>] aarch64_insn_patch_text_nosync+0x18/0x48
[<ffffffc000622ee8>] aarch64_insn_patch_text_cb+0x70/0xa0
[<ffffffc000622f40>] aarch64_insn_patch_text_sync+0x28/0x48
[<ffffffc0006236e0>] arch_arm_kprobe+0x38/0x48
[<ffffffc00010e6f4>] arm_kprobe+0x34/0x50
[<ffffffc000110374>] register_kprobe+0x4cc/0x5b8
[<ffffffbffc002038>] kprobe_init+0x38/0x7c [kprobe_example]
[<ffffffc000084240>] do_one_initcall+0x90/0x1b0
[<ffffffc00061c498>] do_init_module+0x6c/0x1cc
[<ffffffc0000fd0c0>] load_module+0x17f8/0x1db0
[<ffffffc0000fd8cc>] SyS_finit_module+0xb4/0xc8

Convert patch_lock to raw loc kto avoid this issue.

Although the problem is found on rt kernel, the fix should be applicable to
mainline kernel too.

Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Yang Shi <yang.shi@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
shenki pushed a commit that referenced this pull request Nov 13, 2015
When freqdomain_cpus attribute is read from an offlined cpu, it will
cause crash. This change prevents calling cpufreq_show_cpus when
policy driver_data is NULL.

Crash info:

[  170.814949] BUG: unable to handle kernel NULL pointer dereference at 0000000000000018
[  170.814990] IP: [<ffffffff813b2490>] _find_next_bit.part.0+0x10/0x70
[  170.815021] PGD 227d30067 PUD 229e56067 PMD 0
[  170.815043] Oops: 0000 [#2] SMP
[  170.816022] CPU: 3 PID: 3121 Comm: cat Tainted: G      D    OE   4.3.0-rc3+ #33
...
...
[  170.816657] Call Trace:
[  170.816672]  [<ffffffff813b2505>] ? find_next_bit+0x15/0x20
[  170.816696]  [<ffffffff8160e47c>] cpufreq_show_cpus+0x5c/0xd0
[  170.816722]  [<ffffffffa031a409>] show_freqdomain_cpus+0x19/0x20 [acpi_cpufreq]
[  170.816749]  [<ffffffff8160e65b>] show+0x3b/0x60
[  170.816769]  [<ffffffff8129b31c>] sysfs_kf_seq_show+0xbc/0x130
[  170.816793]  [<ffffffff81299be3>] kernfs_seq_show+0x23/0x30
[  170.816816]  [<ffffffff81240f2c>] seq_read+0xec/0x390
[  170.816837]  [<ffffffff8129a64a>] kernfs_fop_read+0x10a/0x160
[  170.816861]  [<ffffffff8121d9b7>] __vfs_read+0x37/0x100
[  170.816883]  [<ffffffff813217c0>] ? security_file_permission+0xa0/0xc0
[  170.816909]  [<ffffffff8121e2e3>] vfs_read+0x83/0x130
[  170.816930]  [<ffffffff8121f035>] SyS_read+0x55/0xc0
...
...
[  170.817185] ---[ end trace bc6eadf82b2b965a ]---

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: 4.2+ <stable@vger.kernel.org> # 4.2+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
shenki pushed a commit that referenced this pull request Dec 16, 2015
…_BH() in preemptible context.

[ Upstream commit 44f49dd ]

Fixes the following kernel BUG :

BUG: using __this_cpu_add() in preemptible [00000000] code: bash/2758
caller is __this_cpu_preempt_check+0x13/0x15
CPU: 0 PID: 2758 Comm: bash Tainted: P           O   3.18.19 #2
 ffffffff8170eaca ffff880110d1b788 ffffffff81482b2a 0000000000000000
 0000000000000000 ffff880110d1b7b8 ffffffff812010ae ffff880007cab800
 ffff88001a060800 ffff88013a899108 ffff880108b84240 ffff880110d1b7c8
Call Trace:
[<ffffffff81482b2a>] dump_stack+0x52/0x80
[<ffffffff812010ae>] check_preemption_disabled+0xce/0xe1
[<ffffffff812010d4>] __this_cpu_preempt_check+0x13/0x15
[<ffffffff81419d60>] ipmr_queue_xmit+0x647/0x70c
[<ffffffff8141a154>] ip_mr_forward+0x32f/0x34e
[<ffffffff8141af76>] ip_mroute_setsockopt+0xe03/0x108c
[<ffffffff810553fc>] ? get_parent_ip+0x11/0x42
[<ffffffff810e6974>] ? pollwake+0x4d/0x51
[<ffffffff81058ac0>] ? default_wake_function+0x0/0xf
[<ffffffff810553fc>] ? get_parent_ip+0x11/0x42
[<ffffffff810613d9>] ? __wake_up_common+0x45/0x77
[<ffffffff81486ea9>] ? _raw_spin_unlock_irqrestore+0x1d/0x32
[<ffffffff810618bc>] ? __wake_up_sync_key+0x4a/0x53
[<ffffffff8139a519>] ? sock_def_readable+0x71/0x75
[<ffffffff813dd226>] do_ip_setsockopt+0x9d/0xb55
[<ffffffff81429818>] ? unix_seqpacket_sendmsg+0x3f/0x41
[<ffffffff813963fe>] ? sock_sendmsg+0x6d/0x86
[<ffffffff813959d4>] ? sockfd_lookup_light+0x12/0x5d
[<ffffffff8139650a>] ? SyS_sendto+0xf3/0x11b
[<ffffffff810d5738>] ? new_sync_read+0x82/0xaa
[<ffffffff813ddd19>] compat_ip_setsockopt+0x3b/0x99
[<ffffffff813fb24a>] compat_raw_setsockopt+0x11/0x32
[<ffffffff81399052>] compat_sock_common_setsockopt+0x18/0x1f
[<ffffffff813c4d05>] compat_SyS_setsockopt+0x1a9/0x1cf
[<ffffffff813c4149>] compat_SyS_socketcall+0x180/0x1e3
[<ffffffff81488ea1>] cstar_dispatch+0x7/0x1e

Signed-off-by: Ani Sinha <ani@arista.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
shenki pushed a commit that referenced this pull request Dec 16, 2015
commit 1f9c6e1 upstream.

There were several bugs here.

1)  The done label was in the wrong place so we didn't copy any
    information out when there was no command given.

2)  We were using PAGE_SIZE as the size of the buffer instead of
    "PAGE_SIZE - pos".

3)  snprintf() returns the number of characters that would have been
    printed if there were enough space.  If there was not enough space
    (and we had fixed the memory corruption bug #2) then it would result
    in an information leak when we do simple_read_from_buffer().  I've
    changed it to use scnprintf() instead.

I also removed the initialization at the start of the function, because
I thought it made the code a little more clear.

Fixes: 5e6e3a9 ('wireless: mwifiex: initial commit for Marvell mwifiex driver')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Amitkumar Karwar <akarwar@marvell.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
shenki pushed a commit that referenced this pull request Dec 16, 2015
commit cc25b99 upstream.

This fixes CVE-2015-5327.  It affects kernels from 4.3-rc1 onwards.

Fix the X.509 time validation to use month number-1 when looking up the
number of days in that month.  Also put the month number validation before
doing the lookup so as not to risk overrunning the array.

This can be tested by doing the following:

cat <<EOF | openssl x509 -outform DER | keyctl padd asymmetric "" @s
-----BEGIN CERTIFICATE-----
MIIDbjCCAlagAwIBAgIJAN/lUld+VR4hMA0GCSqGSIb3DQEBCwUAMCkxETAPBgNV
BAoMCGxvY2FsLWNhMRQwEgYDVQQDDAtzaWduaW5nIGtleTAeFw0xNTA5MDEyMTMw
MThaFw0xNjA4MzEyMTMwMThaMCkxETAPBgNVBAoMCGxvY2FsLWNhMRQwEgYDVQQD
DAtzaWduaW5nIGtleTCCASIwDQYJKoZIhvcNAQEBBQADggEPADCCAQoCggEBANrn
crcMfMeG67nagX4+m02Xk9rkmsMKI5XTUxbikROe7GSUVJ27sPVPZp4mgzoWlvhh
jfK8CC/qhEhwep8Pgg4EJZyWOjhZb7R97ckGvLIoUC6IO3FC2ZnR7WtmWDgo2Jcj
VlXwJdHhKU1VZwulh81O61N8IBKqz2r/kDhIWiicUCUkI/Do/RMRfKAoDBcSh86m
gOeIAGfq62vbiZhVsX5dOE8Oo2TK5weAvwUIOR7OuGBl5AqwFlPnXQolewiHzKry
THg9e44HfzG4Mi6wUvcJxVaQT1h5SrKD779Z5+8+wf1JLaooetcEUArvWyuxCU59
qxA4lsTjBwl4cmEki+cCAwEAAaOBmDCBlTAMBgNVHRMEBTADAQH/MAsGA1UdDwQE
AwIHgDAdBgNVHQ4EFgQUyND/eKUis7ep/hXMJ8iZMdUhI+IwWQYDVR0jBFIwUIAU
yND/eKUis7ep/hXMJ8iZMdUhI+KhLaQrMCkxETAPBgNVBAoMCGxvY2FsLWNhMRQw
EgYDVQQDDAtzaWduaW5nIGtleYIJAN/lUld+VR4hMA0GCSqGSIb3DQEBCwUAA4IB
AQAMqm1N1yD5pimUELLhT5eO2lRdGUfTozljRxc7e2QT3RLk2TtGhg65JFFN6eml
XS58AEPVcAsSLDlR6WpOpOLB2giM0+fV/eYFHHmh22yqTJl4YgkdUwyzPdCHNOZL
hmSKeY9xliHb6PNrNWWtZwhYYvRaO2DX4GXOMR0Oa2O4vaYu6/qGlZOZv3U6qZLY
wwHEJSrqeBDyMuwN+eANHpoSpiBzD77S4e+7hUDJnql4j6xzJ65+nWJ89fCrQypR
4sN5R3aGeIh3QAQUIKpHilwek0CtEaYERgc5m+jGyKSc1rezJW62hWRTaitOc+d5
G5hh+9YpnYcxQHEKnZ7rFNKJ
-----END CERTIFICATE-----
EOF

If it works, it emit a key ID; if it fails, it should give a bad message
error.

Reported-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
shenki pushed a commit that referenced this pull request Dec 16, 2015
[ Upstream commit b4fe85f ]

Drivers like vxlan use the recently introduced
udp_tunnel_xmit_skb/udp_tunnel6_xmit_skb APIs. udp_tunnel6_xmit_skb
makes use of ip6tunnel_xmit, and ip6tunnel_xmit, after sending the
packet, updates the struct stats using the usual
u64_stats_update_begin/end calls on this_cpu_ptr(dev->tstats).
udp_tunnel_xmit_skb makes use of iptunnel_xmit, which doesn't touch
tstats, so drivers like vxlan, immediately after, call
iptunnel_xmit_stats, which does the same thing - calls
u64_stats_update_begin/end on this_cpu_ptr(dev->tstats).

While vxlan is probably fine (I don't know?), calling a similar function
from, say, an unbound workqueue, on a fully preemptable kernel causes
real issues:

[  188.434537] BUG: using smp_processor_id() in preemptible [00000000] code: kworker/u8:0/6
[  188.435579] caller is debug_smp_processor_id+0x17/0x20
[  188.435583] CPU: 0 PID: 6 Comm: kworker/u8:0 Not tainted 4.2.6 #2
[  188.435607] Call Trace:
[  188.435611]  [<ffffffff8234e936>] dump_stack+0x4f/0x7b
[  188.435615]  [<ffffffff81915f3d>] check_preemption_disabled+0x19d/0x1c0
[  188.435619]  [<ffffffff81915f77>] debug_smp_processor_id+0x17/0x20

The solution would be to protect the whole
this_cpu_ptr(dev->tstats)/u64_stats_update_begin/end blocks with
disabling preemption and then reenabling it.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
shenki pushed a commit that referenced this pull request Dec 16, 2015
[ Upstream commit 1b8e6a0 ]

When a passive TCP is created, we eventually call tcp_md5_do_add()
with sk pointing to the child. It is not owner by the user yet (we
will add this socket into listener accept queue a bit later anyway)

But we do own the spinlock, so amend the lockdep annotation to avoid
following splat :

[ 8451.090932] net/ipv4/tcp_ipv4.c:923 suspicious rcu_dereference_protected() usage!
[ 8451.090932]
[ 8451.090932] other info that might help us debug this:
[ 8451.090932]
[ 8451.090934]
[ 8451.090934] rcu_scheduler_active = 1, debug_locks = 1
[ 8451.090936] 3 locks held by socket_sockopt_/214795:
[ 8451.090936]  #0:  (rcu_read_lock){.+.+..}, at: [<ffffffff855c6ac1>] __netif_receive_skb_core+0x151/0xe90
[ 8451.090947]  #1:  (rcu_read_lock){.+.+..}, at: [<ffffffff85618143>] ip_local_deliver_finish+0x43/0x2b0
[ 8451.090952]  #2:  (slock-AF_INET){+.-...}, at: [<ffffffff855acda5>] sk_clone_lock+0x1c5/0x500
[ 8451.090958]
[ 8451.090958] stack backtrace:
[ 8451.090960] CPU: 7 PID: 214795 Comm: socket_sockopt_

[ 8451.091215] Call Trace:
[ 8451.091216]  <IRQ>  [<ffffffff856fb29c>] dump_stack+0x55/0x76
[ 8451.091229]  [<ffffffff85123b5b>] lockdep_rcu_suspicious+0xeb/0x110
[ 8451.091235]  [<ffffffff8564544f>] tcp_md5_do_add+0x1bf/0x1e0
[ 8451.091239]  [<ffffffff85645751>] tcp_v4_syn_recv_sock+0x1f1/0x4c0
[ 8451.091242]  [<ffffffff85642b27>] ? tcp_v4_md5_hash_skb+0x167/0x190
[ 8451.091246]  [<ffffffff85647c78>] tcp_check_req+0x3c8/0x500
[ 8451.091249]  [<ffffffff856451ae>] ? tcp_v4_inbound_md5_hash+0x11e/0x190
[ 8451.091253]  [<ffffffff85647170>] tcp_v4_rcv+0x3c0/0x9f0
[ 8451.091256]  [<ffffffff85618143>] ? ip_local_deliver_finish+0x43/0x2b0
[ 8451.091260]  [<ffffffff856181b6>] ip_local_deliver_finish+0xb6/0x2b0
[ 8451.091263]  [<ffffffff85618143>] ? ip_local_deliver_finish+0x43/0x2b0
[ 8451.091267]  [<ffffffff85618d38>] ip_local_deliver+0x48/0x80
[ 8451.091270]  [<ffffffff85618510>] ip_rcv_finish+0x160/0x700
[ 8451.091273]  [<ffffffff8561900e>] ip_rcv+0x29e/0x3d0
[ 8451.091277]  [<ffffffff855c74b7>] __netif_receive_skb_core+0xb47/0xe90

Fixes: a8afca0 ("tcp: md5: protects md5sig_info with RCU")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
nkskjames pushed a commit to nkskjames/linux that referenced this pull request Jan 13, 2016
Kernel testing triggered this warning:

| WARNING: CPU: 0 PID: 13 at kernel/sched/core.c:1156 do_set_cpus_allowed+0x7e/0x80()
| Modules linked in:
| CPU: 0 PID: 13 Comm: migration/0 Not tainted 4.2.0-rc1-00049-g25834c7 openbmc#2
| Call Trace:
|   dump_stack+0x4b/0x75
|   warn_slowpath_common+0x8b/0xc0
|   warn_slowpath_null+0x22/0x30
|   do_set_cpus_allowed+0x7e/0x80
|   cpuset_cpus_allowed_fallback+0x7c/0x170
|   select_fallback_rq+0x221/0x280
|   migration_call+0xe3/0x250
|   notifier_call_chain+0x53/0x70
|   __raw_notifier_call_chain+0x1e/0x30
|   cpu_notify+0x28/0x50
|   take_cpu_down+0x22/0x40
|   multi_cpu_stop+0xd5/0x140
|   cpu_stopper_thread+0xbc/0x170
|   smpboot_thread_fn+0x174/0x2f0
|   kthread+0xc4/0xe0
|   ret_from_kernel_thread+0x21/0x30

As Peterz pointed out:

| So the normal rules for changing task_struct::cpus_allowed are holding
| both pi_lock and rq->lock, such that holding either stabilizes the mask.
|
| This is so that wakeup can happen without rq->lock and load-balance
| without pi_lock.
|
| From this we already get the relaxation that we can omit acquiring
| rq->lock if the task is not on the rq, because in that case
| load-balancing will not apply to it.
|
| ** these are the rules currently tested in do_set_cpus_allowed() **
|
| Now, since __set_cpus_allowed_ptr() uses task_rq_lock() which
| unconditionally acquires both locks, we could get away with holding just
| rq->lock when on_rq for modification because that'd still exclude
| __set_cpus_allowed_ptr(), it would also work against
| __kthread_bind_mask() because that assumes !on_rq.
|
| That said, this is all somewhat fragile.
|
| Now, I don't think dropping rq->lock is quite as disastrous as it
| usually is because !cpu_active at this point, which means load-balance
| will not interfere, but that too is somewhat fragile.
|
| So we end up with a choice of two fragile..

This patch fixes it by following the rules for changing
task_struct::cpus_allowed with both pi_lock and rq->lock held.

Reported-by: kernel test robot <ying.huang@intel.com>
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
[ Modified changelog and patch. ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
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/BLU436-SMTP1660820490DE202E3934ED3806E0@phx.gbl
Signed-off-by: Ingo Molnar <mingo@kernel.org>
nkskjames pushed a commit to nkskjames/linux that referenced this pull request Jan 13, 2016
The renesas-irqc interrupt controller is cascaded to the GIC. Hence when
propagating wake-up settings to its parent interrupt controller, the
following lockdep warning is printed:

    =============================================
    [ INFO: possible recursive locking detected ]
    4.2.0-ape6evm-10725-g50fcd7643c034198 torvalds#280 Not tainted
    ---------------------------------------------
    s2ram/1072 is trying to acquire lock:
    (&irq_desc_lock_class){-.-...}, at: [<c008d3fc>] __irq_get_desc_lock+0x58/0x98

    but task is already holding lock:
    (&irq_desc_lock_class){-.-...}, at: [<c008d3fc>] __irq_get_desc_lock+0x58/0x98

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

	  CPU0
	  ----
     lock(&irq_desc_lock_class);
     lock(&irq_desc_lock_class);

    *** DEADLOCK ***

    May be due to missing lock nesting notation

    6 locks held by s2ram/1072:
    #0:  (sb_writers#7){.+.+.+}, at: [<c012eb14>] __sb_start_write+0xa0/0xa8
    openbmc#1:  (&of->mutex){+.+.+.}, at: [<c019396c>] kernfs_fop_write+0x4c/0x1bc
    openbmc#2:  (s_active#24){.+.+.+}, at: [<c0193974>] kernfs_fop_write+0x54/0x1bc
    openbmc#3:  (pm_mutex){+.+.+.}, at: [<c008213c>] pm_suspend+0x10c/0x510
    openbmc#4:  (&dev->mutex){......}, at: [<c02af3c4>] __device_suspend+0xdc/0x2cc
    openbmc#5:  (&irq_desc_lock_class){-.-...}, at: [<c008d3fc>] __irq_get_desc_lock+0x58/0x98

    stack backtrace:
    CPU: 0 PID: 1072 Comm: s2ram Not tainted 4.2.0-ape6evm-10725-g50fcd7643c034198 torvalds#280
    Hardware name: Generic R8A73A4 (Flattened Device Tree)
    [<c0018078>] (unwind_backtrace) from [<c00144f0>] (show_stack+0x10/0x14)
    [<c00144f0>] (show_stack) from [<c0451f14>] (dump_stack+0x88/0x98)
    [<c0451f14>] (dump_stack) from [<c007b29c>] (__lock_acquire+0x15cc/0x20e4)
    [<c007b29c>] (__lock_acquire) from [<c007c6e0>] (lock_acquire+0xac/0x12c)
    [<c007c6e0>] (lock_acquire) from [<c0457c00>] (_raw_spin_lock_irqsave+0x40/0x54)
    [<c0457c00>] (_raw_spin_lock_irqsave) from [<c008d3fc>] (__irq_get_desc_lock+0x58/0x98)
    [<c008d3fc>] (__irq_get_desc_lock) from [<c008ebbc>] (irq_set_irq_wake+0x20/0xf8)
    [<c008ebbc>] (irq_set_irq_wake) from [<c0260770>] (irqc_irq_set_wake+0x20/0x4c)
    [<c0260770>] (irqc_irq_set_wake) from [<c008ec28>] (irq_set_irq_wake+0x8c/0xf8)
    [<c008ec28>] (irq_set_irq_wake) from [<c02cb8c0>] (gpio_keys_suspend+0x74/0xc0)
    [<c02cb8c0>] (gpio_keys_suspend) from [<c02ae8cc>] (dpm_run_callback+0x54/0x124)

Avoid this false positive by using a separate lockdep class for IRQC
interrupts.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/1441798974-25716-2-git-send-email-geert%2Brenesas@glider.be
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
nkskjames pushed a commit to nkskjames/linux that referenced this pull request Jan 13, 2016
The renesas-intc-irqpin interrupt controller is cascaded to the GIC.
Hence when propagating wake-up settings to its parent interrupt
controller, the following lockdep warning is printed:

    =============================================
    [ INFO: possible recursive locking detected ]
    4.2.0-armadillo-10725-g50fcd7643c034198 torvalds#781 Not tainted
    ---------------------------------------------
    s2ram/1179 is trying to acquire lock:
    (&irq_desc_lock_class){-.-...}, at: [<c005bb54>] __irq_get_desc_lock+0x78/0x94

    but task is already holding lock:
    (&irq_desc_lock_class){-.-...}, at: [<c005bb54>] __irq_get_desc_lock+0x78/0x94

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

	  CPU0
	  ----
     lock(&irq_desc_lock_class);
     lock(&irq_desc_lock_class);

    *** DEADLOCK ***

    May be due to missing lock nesting notation

    7 locks held by s2ram/1179:
    #0:  (sb_writers#7){.+.+.+}, at: [<c00c9708>] __sb_start_write+0x64/0xb8
    openbmc#1:  (&of->mutex){+.+.+.}, at: [<c0125a00>] kernfs_fop_write+0x78/0x1a0
    openbmc#2:  (s_active#23){.+.+.+}, at: [<c0125a08>] kernfs_fop_write+0x80/0x1a0
    openbmc#3:  (autosleep_lock){+.+.+.}, at: [<c0058244>] pm_autosleep_lock+0x18/0x20
    openbmc#4:  (pm_mutex){+.+.+.}, at: [<c0057e50>] pm_suspend+0x54/0x248
    openbmc#5:  (&dev->mutex){......}, at: [<c0243a20>] __device_suspend+0xdc/0x240
    openbmc#6:  (&irq_desc_lock_class){-.-...}, at: [<c005bb54>] __irq_get_desc_lock+0x78/0x94

    stack backtrace:
    CPU: 0 PID: 1179 Comm: s2ram Not tainted 4.2.0-armadillo-10725-g50fcd7643c034198

    Hardware name: Generic R8A7740 (Flattened Device Tree)
    [<c00129f4>] (dump_backtrace) from [<c0012bec>] (show_stack+0x18/0x1c)
    [<c0012bd4>] (show_stack) from [<c03f5d94>] (dump_stack+0x20/0x28)
    [<c03f5d74>] (dump_stack) from [<c00514d4>] (__lock_acquire+0x67c/0x1b88)
    [<c0050e58>] (__lock_acquire) from [<c0052df8>] (lock_acquire+0x9c/0xbc)
    [<c0052d5c>] (lock_acquire) from [<c03fb068>] (_raw_spin_lock_irqsave+0x44/0x58)
    [<c03fb024>] (_raw_spin_lock_irqsave) from [<c005bb54>] (__irq_get_desc_lock+0x78/0x94
    [<c005badc>] (__irq_get_desc_lock) from [<c005c3d8>] (irq_set_irq_wake+0x28/0x100)
    [<c005c3b0>] (irq_set_irq_wake) from [<c01e50d0>] (intc_irqpin_irq_set_wake+0x24/0x4c)
    [<c01e50ac>] (intc_irqpin_irq_set_wake) from [<c005c17c>] (set_irq_wake_real+0x3c/0x50
    [<c005c140>] (set_irq_wake_real) from [<c005c414>] (irq_set_irq_wake+0x64/0x100)
    [<c005c3b0>] (irq_set_irq_wake) from [<c02a19b4>] (gpio_keys_suspend+0x60/0xa0)
    [<c02a1954>] (gpio_keys_suspend) from [<c023b750>] (platform_pm_suspend+0x3c/0x5c)

Avoid this false positive by using a separate lockdep class for INTC
External IRQ Pin interrupts.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/1441798974-25716-3-git-send-email-geert%2Brenesas@glider.be
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
nkskjames pushed a commit to nkskjames/linux that referenced this pull request Jan 13, 2016
The OPP list needs to be protected against concurrent accesses. Using
simple RCU read locks does the trick and gets rid of the following
lockdep warning:

	===============================
	[ INFO: suspicious RCU usage. ]
	4.2.0-next-20150908 openbmc#1 Not tainted
	-------------------------------
	drivers/base/power/opp.c:460 Missing rcu_read_lock() or dev_opp_list_lock protection!

	other info that might help us debug this:

	rcu_scheduler_active = 1, debug_locks = 0
	4 locks held by kworker/u8:0/6:
	 #0:  ("%s""deferwq"){++++.+}, at: [<c0040d8c>] process_one_work+0x118/0x4bc
	 openbmc#1:  (deferred_probe_work){+.+.+.}, at: [<c0040d8c>] process_one_work+0x118/0x4bc
	 openbmc#2:  (&dev->mutex){......}, at: [<c03b8194>] __device_attach+0x20/0x118
	 openbmc#3:  (prepare_lock){+.+...}, at: [<c054bc08>] clk_prepare_lock+0x10/0xf8

	stack backtrace:
	CPU: 2 PID: 6 Comm: kworker/u8:0 Not tainted 4.2.0-next-20150908 openbmc#1
	Hardware name: NVIDIA Tegra SoC (Flattened Device Tree)
	Workqueue: deferwq deferred_probe_work_func
	[<c001802c>] (unwind_backtrace) from [<c00135a4>] (show_stack+0x10/0x14)
	[<c00135a4>] (show_stack) from [<c02a8418>] (dump_stack+0x94/0xd4)
	[<c02a8418>] (dump_stack) from [<c03c6f6c>] (dev_pm_opp_find_freq_ceil+0x108/0x114)
	[<c03c6f6c>] (dev_pm_opp_find_freq_ceil) from [<c0551a3c>] (dfll_calculate_rate_request+0xb8/0x170)
	[<c0551a3c>] (dfll_calculate_rate_request) from [<c0551b10>] (dfll_clk_round_rate+0x1c/0x2c)
	[<c0551b10>] (dfll_clk_round_rate) from [<c054de2c>] (clk_calc_new_rates+0x1b8/0x228)
	[<c054de2c>] (clk_calc_new_rates) from [<c054e44c>] (clk_core_set_rate_nolock+0x44/0xac)
	[<c054e44c>] (clk_core_set_rate_nolock) from [<c054e4d8>] (clk_set_rate+0x24/0x34)
	[<c054e4d8>] (clk_set_rate) from [<c0512460>] (tegra124_cpufreq_probe+0x120/0x230)
	[<c0512460>] (tegra124_cpufreq_probe) from [<c03b9cbc>] (platform_drv_probe+0x44/0xac)
	[<c03b9cbc>] (platform_drv_probe) from [<c03b84c8>] (driver_probe_device+0x218/0x304)
	[<c03b84c8>] (driver_probe_device) from [<c03b69b0>] (bus_for_each_drv+0x60/0x94)
	[<c03b69b0>] (bus_for_each_drv) from [<c03b8228>] (__device_attach+0xb4/0x118)
	ata1: SATA link down (SStatus 0 SControl 300)
	[<c03b8228>] (__device_attach) from [<c03b77c8>] (bus_probe_device+0x88/0x90)
	[<c03b77c8>] (bus_probe_device) from [<c03b7be8>] (deferred_probe_work_func+0x58/0x8c)
	[<c03b7be8>] (deferred_probe_work_func) from [<c0040dfc>] (process_one_work+0x188/0x4bc)
	[<c0040dfc>] (process_one_work) from [<c004117c>] (worker_thread+0x4c/0x4f4)
	[<c004117c>] (worker_thread) from [<c0047230>] (kthread+0xe4/0xf8)
	[<c0047230>] (kthread) from [<c000f7d0>] (ret_from_fork+0x14/0x24)

Signed-off-by: Thierry Reding <treding@nvidia.com>
Fixes: c4fe70a ("clk: tegra: Add closed loop support for the DFLL")
[vince.h@nvidia.com: Unlock rcu on error path]
Signed-off-by: Vince Hsu <vince.h@nvidia.com>
[sboyd@codeaurora.org: Dropped second hunk that nested the rcu
read lock unnecessarily]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
nkskjames pushed a commit to nkskjames/linux that referenced this pull request Jan 13, 2016
…t initialized.

In case something goes wrong with power well initialization we were calling
intel_prepare_ddi during boot while encoder list isnt't initilized.

[    9.618747] i915 0000:00:02.0: Invalid ROM contents
[    9.631446] [drm] failed to find VBIOS tables
[    9.720036] BUG: unable to handle kernel NULL pointer dereference at 00000000
00000058
[    9.721986] IP: [<ffffffffa014eb72>] ddi_get_encoder_port+0x82/0x190 [i915]
[    9.723736] PGD 0
[    9.724286] Oops: 0000 [openbmc#1] PREEMPT SMP
[    9.725386] Modules linked in: intel_powerclamp snd_hda_intel(+) coretemp crc
32c_intel snd_hda_codec snd_hda_core serio_raw snd_pcm snd_timer i915(+) parport
_pc parport pinctrl_sunrisepoint pinctrl_intel nfsd nfs_acl
[    9.730635] CPU: 0 PID: 497 Comm: systemd-udevd Not tainted 4.3.0-rc2-eywa-10
967-g72de2cfd-dirty openbmc#2
[    9.732785] Hardware name: Intel Corporation Cannonlake Client platform/Skyla
ke DT DDR4 RVP8, BIOS CNLSE2R1.R00.X021.B00.1508040310 08/04/2015
[    9.735785] task: ffff88008a704700 ti: ffff88016a1ac000 task.ti: ffff88016a1a
c000
[    9.737584] RIP: 0010:[<ffffffffa014eb72>]  [<ffffffffa014eb72>] ddi_get_enco
der_port+0x82/0x190 [i915]
[    9.739934] RSP: 0000:ffff88016a1af710  EFLAGS: 00010296
[    9.741184] RAX: 000000000000004e RBX: ffff88008a9edc98 RCX: 0000000000000001
[    9.742934] RDX: 000000000000004e RSI: ffffffff81fc1e82 RDI: 00000000ffffffff
[    9.744634] RBP: ffff88016a1af730 R08: 0000000000000000 R09: 0000000000000578
[    9.746333] R10: 0000000000001065 R11: 0000000000000578 R12: fffffffffffffff8
[    9.748033] R13: ffff88016a1af7a8 R14: ffff88016a1af794 R15: 0000000000000000
[    9.749733] FS:  00007eff2e1e07c0(0000) GS:ffff88016fc00000(0000) knlGS:00000
00000000000
[    9.751683] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    9.753083] CR2: 0000000000000058 CR3: 000000016922b000 CR4: 00000000003406f0
[    9.754782] Stack:
[    9.755332]  ffff88008a9edc98 ffff88008a9ed800 ffffffffa01d07b0 00000000fffb9
09e
[    9.757232]  ffff88016a1af7d8 ffffffffa0154ea7 0000000000000246 ffff88016a370
080
[    9.759182]  ffff88016a370080 ffff88008a9ed800 0000000000000246 ffff88008a9ed
c98
[    9.761132] Call Trace:
[    9.761782]  [<ffffffffa0154ea7>] intel_prepare_ddi+0x67/0x860 [i915]
[    9.763332]  [<ffffffff81a56996>] ? _raw_spin_unlock_irqrestore+0x26/0x40
[    9.765031]  [<ffffffffa00fad01>] ? gen9_read32+0x141/0x360 [i915]
[    9.766531]  [<ffffffffa00b43e1>] skl_set_power_well+0x431/0xa80 [i915]
[    9.768181]  [<ffffffffa00b4a63>] skl_power_well_enable+0x13/0x20 [i915]
[    9.769781]  [<ffffffffa00b2188>] intel_power_well_enable+0x28/0x50 [i915]
[    9.771481]  [<ffffffffa00b4d52>] intel_display_power_get+0x92/0xc0 [i915]
[    9.773180]  [<ffffffffa00b4fcb>] intel_display_set_init_power+0x3b/0x40 [i91
5]
[    9.774980]  [<ffffffffa00b5170>] intel_power_domains_init_hw+0x120/0x520 [i9
15]
[    9.776780]  [<ffffffffa0194c61>] i915_driver_load+0xb21/0xf40 [i915]

So let's protect this case.

My first attempt was to remove the intel_prepare_ddi, but Daniel had pointed out
this is really needed to restore those registers values. And Imre pointed out
that this case was without the flag protection and this was actually where things
were going bad. So I've just checked and this indeed solves my issue.

The regressing intel_prepare_ddi call was added in

commit 1d2b952
Author: Damien Lespiau <damien.lespiau@intel.com>
Date:   Fri Mar 6 18:50:53 2015 +0000

    drm/i915/skl: Restore the DDI translation tables when enabling PW1

Cc: Imre Deak <imre.deak@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
[Jani: regression reference]
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
nkskjames pushed a commit to nkskjames/linux that referenced this pull request Jan 13, 2016
Dmitry Vyukov reported the following using trinity and the memory
error detector AddressSanitizer
(https://code.google.com/p/address-sanitizer/wiki/AddressSanitizerForKernel).

[ 124.575597] ERROR: AddressSanitizer: heap-buffer-overflow on
address ffff88002e280000
[ 124.576801] ffff88002e280000 is located 131938492886538 bytes to
the left of 28857600-byte region [ffffffff81282e0a, ffffffff82e0830a)
[ 124.578633] Accessed by thread T10915:
[ 124.579295] inlined in describe_heap_address
./arch/x86/mm/asan/report.c:164
[ 124.579295] #0 ffffffff810dd277 in asan_report_error
./arch/x86/mm/asan/report.c:278
[ 124.580137] openbmc#1 ffffffff810dc6a0 in asan_check_region
./arch/x86/mm/asan/asan.c:37
[ 124.581050] openbmc#2 ffffffff810dd423 in __tsan_read8 ??:0
[ 124.581893] openbmc#3 ffffffff8107c093 in get_wchan
./arch/x86/kernel/process_64.c:444

The address checks in the 64bit implementation of get_wchan() are
wrong in several ways:

 - The lower bound of the stack is not the start of the stack
   page. It's the start of the stack page plus sizeof (struct
   thread_info)

 - The upper bound must be:

       top_of_stack - TOP_OF_KERNEL_STACK_PADDING - 2 * sizeof(unsigned long).

   The 2 * sizeof(unsigned long) is required because the stack pointer
   points at the frame pointer. The layout on the stack is: ... IP FP
   ... IP FP. So we need to make sure that both IP and FP are in the
   bounds.

Fix the bound checks and get rid of the mix of numeric constants, u64
and unsigned long. Making all unsigned long allows us to use the same
function for 32bit as well.

Use READ_ONCE() when accessing the stack. This does not prevent a
concurrent wakeup of the task and the stack changing, but at least it
avoids TOCTOU.

Also check task state at the end of the loop. Again that does not
prevent concurrent changes, but it avoids walking for nothing.

Add proper comments while at it.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Based-on-patch-from: Wolfram Gloger <wmglo@dent.med.uni-muenchen.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@alien8.de>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Kostya Serebryany <kcc@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: kasan-dev <kasan-dev@googlegroups.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Wolfram Gloger <wmglo@dent.med.uni-muenchen.de>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20150930083302.694788319@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
nkskjames pushed a commit to nkskjames/linux that referenced this pull request Jan 13, 2016
Commit 1a3d595 ("MIPS: Tidy up FPU context switching") removed FP
context saving from the asm-written resume function in favour of reusing
existing code to perform the same task. However it only removed the FP
context saving code from the r4k_switch.S implementation of resume.
Octeon uses its own implementation in octeon_switch.S, so remove FP
context saving there too in order to prevent attempting to save context
twice. That formerly led to an exception from the second save as follows
because the FPU had already been disabled by the first save:

    do_cpu invoked from kernel context![openbmc#1]:
    CPU: 0 PID: 2 Comm: kthreadd Not tainted 4.3.0-rc2-dirty openbmc#2
    task: 800000041f84a008 ti: 800000041f864000 task.ti: 800000041f864000
    $ 0   : 0000000000000000 0000000010008ce1 0000000000100000 ffffffffbfffffff
    $ 4   : 800000041f84a008 800000041f84ac08 800000041f84c000 0000000000000004
    $ 8   : 0000000000000001 0000000000000000 0000000000000000 0000000000000001
    $12   : 0000000010008ce3 0000000000119c60 0000000000000036 800000041f864000
    $16   : 800000041f84ac08 800000000792ce80 800000041f84a008 ffffffff81758b00
    $20   : 0000000000000000 ffffffff8175ae50 0000000000000000 ffffffff8176c740
    $24   : 0000000000000006 ffffffff81170300
    $28   : 800000041f864000 800000041f867d90 0000000000000000 ffffffff815f3fa0
    Hi    : 0000000000fa8257
    Lo    : ffffffffe15cfc00
    epc   : ffffffff8112821c resume+0x9c/0x200
    ra    : ffffffff815f3fa0 __schedule+0x3f0/0x7d8
    Status: 10008ce2        KX SX UX KERNEL EXL
    Cause : 1080002c (ExcCode 0b)
    PrId  : 000d0601 (Cavium Octeon+)
    Modules linked in:
    Process kthreadd (pid: 2, threadinfo=800000041f864000, task=800000041f84a008, tls=0000000000000000)
    Stack : ffffffff81604218 ffffffff815f7e08 800000041f84a008 ffffffff811681b0
              800000041f84a008 ffffffff817e9878 0000000000000000 ffffffff81770000
              ffffffff81768340 ffffffff81161398 0000000000000001 0000000000000000
              0000000000000000 ffffffff815f4424 0000000000000000 ffffffff81161d68
              ffffffff81161be8 0000000000000000 0000000000000000 0000000000000000
              0000000000000000 0000000000000000 0000000000000000 ffffffff8111e16c
              0000000000000000 0000000000000000 0000000000000000 0000000000000000
              0000000000000000 0000000000000000 0000000000000000 0000000000000000
              0000000000000000 0000000000000000 0000000000000000 0000000000000000
              0000000000000000 0000000000000000 0000000000000000 0000000000000000
              ...
    Call Trace:
    [<ffffffff8112821c>] resume+0x9c/0x200
    [<ffffffff815f3fa0>] __schedule+0x3f0/0x7d8
    [<ffffffff815f4424>] schedule+0x34/0x98
    [<ffffffff81161d68>] kthreadd+0x180/0x198
    [<ffffffff8111e16c>] ret_from_kernel_thread+0x14/0x1c

Tested using cavium_octeon_defconfig on an EdgeRouter Lite.

Fixes: 1a3d595 ("MIPS: Tidy up FPU context switching")
Reported-by: Aaro Koskinen <aaro.koskinen@nokia.com>
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Aleksey Makarov <aleksey.makarov@auriga.com>
Cc: linux-kernel@vger.kernel.org
Cc: Chandrakala Chavva <cchavva@caviumnetworks.com>
Cc: David Daney <david.daney@cavium.com>
Cc: Leonid Rosenboim <lrosenboim@caviumnetworks.com>
Patchwork: https://patchwork.linux-mips.org/patch/11166/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
nkskjames pushed a commit to nkskjames/linux that referenced this pull request Jan 13, 2016
My colleague ran into a program stall on a x86_64 server, where
n_tty_read() was waiting for data even if there was data in the buffer
in the pty.  kernel stack for the stuck process looks like below.
 #0 [ffff88303d107b58] __schedule at ffffffff815c4b20
 openbmc#1 [ffff88303d107bd0] schedule at ffffffff815c513e
 openbmc#2 [ffff88303d107bf0] schedule_timeout at ffffffff815c7818
 openbmc#3 [ffff88303d107ca0] wait_woken at ffffffff81096bd2
 openbmc#4 [ffff88303d107ce0] n_tty_read at ffffffff8136fa23
 openbmc#5 [ffff88303d107dd0] tty_read at ffffffff81368013
 openbmc#6 [ffff88303d107e20] __vfs_read at ffffffff811a3704
 openbmc#7 [ffff88303d107ec0] vfs_read at ffffffff811a3a57
 openbmc#8 [ffff88303d107f00] sys_read at ffffffff811a4306
 openbmc#9 [ffff88303d107f50] entry_SYSCALL_64_fastpath at ffffffff815c86d7

There seems to be two problems causing this issue.

First, in drivers/tty/n_tty.c, __receive_buf() stores the data and
updates ldata->commit_head using smp_store_release() and then checks
the wait queue using waitqueue_active().  However, since there is no
memory barrier, __receive_buf() could return without calling
wake_up_interactive_poll(), and at the same time, n_tty_read() could
start to wait in wait_woken() as in the following chart.

        __receive_buf()                         n_tty_read()
------------------------------------------------------------------------
if (waitqueue_active(&tty->read_wait))
/* Memory operations issued after the
   RELEASE may be completed before the
   RELEASE operation has completed */
                                        add_wait_queue(&tty->read_wait, &wait);
                                        ...
                                        if (!input_available_p(tty, 0)) {
smp_store_release(&ldata->commit_head,
                  ldata->read_head);
                                        ...
                                        timeout = wait_woken(&wait,
                                          TASK_INTERRUPTIBLE, timeout);
------------------------------------------------------------------------

The second problem is that n_tty_read() also lacks a memory barrier
call and could also cause __receive_buf() to return without calling
wake_up_interactive_poll(), and n_tty_read() to wait in wait_woken()
as in the chart below.

        __receive_buf()                         n_tty_read()
------------------------------------------------------------------------
                                        spin_lock_irqsave(&q->lock, flags);
                                        /* from add_wait_queue() */
                                        ...
                                        if (!input_available_p(tty, 0)) {
                                        /* Memory operations issued after the
                                           RELEASE may be completed before the
                                           RELEASE operation has completed */
smp_store_release(&ldata->commit_head,
                  ldata->read_head);
if (waitqueue_active(&tty->read_wait))
                                        __add_wait_queue(q, wait);
                                        spin_unlock_irqrestore(&q->lock,flags);
                                        /* from add_wait_queue() */
                                        ...
                                        timeout = wait_woken(&wait,
                                          TASK_INTERRUPTIBLE, timeout);
------------------------------------------------------------------------

There are also other places in drivers/tty/n_tty.c which have similar
calls to waitqueue_active(), so instead of adding many memory barrier
calls, this patch simply removes the call to waitqueue_active(),
leaving just wake_up*() behind.

This fixes both problems because, even though the memory access before
or after the spinlocks in both wake_up*() and add_wait_queue() can
sneak into the critical section, it cannot go past it and the critical
section assures that they will be serialized (please see "INTER-CPU
ACQUIRING BARRIER EFFECTS" in Documentation/memory-barriers.txt for a
better explanation).  Moreover, the resulting code is much simpler.

Latency measurement using a ping-pong test over a pty doesn't show any
visible performance drop.

Signed-off-by: Kosuke Tatsukawa <tatsu@ab.jp.nec.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
nkskjames pushed a commit to nkskjames/linux that referenced this pull request Jan 13, 2016
When running kprobe test on arm64 rt kernel, it reports the below warning:

root@qemu7:~# modprobe kprobe_example
BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:917
in_atomic(): 0, irqs_disabled(): 128, pid: 484, name: modprobe
CPU: 0 PID: 484 Comm: modprobe Not tainted 4.1.6-rt5 openbmc#2
Hardware name: linux,dummy-virt (DT)
Call trace:
[<ffffffc0000891b8>] dump_backtrace+0x0/0x128
[<ffffffc000089300>] show_stack+0x20/0x30
[<ffffffc00061dae8>] dump_stack+0x1c/0x28
[<ffffffc0000bbad0>] ___might_sleep+0x120/0x198
[<ffffffc0006223e8>] rt_spin_lock+0x28/0x40
[<ffffffc000622b30>] __aarch64_insn_write+0x28/0x78
[<ffffffc000622e48>] aarch64_insn_patch_text_nosync+0x18/0x48
[<ffffffc000622ee8>] aarch64_insn_patch_text_cb+0x70/0xa0
[<ffffffc000622f40>] aarch64_insn_patch_text_sync+0x28/0x48
[<ffffffc0006236e0>] arch_arm_kprobe+0x38/0x48
[<ffffffc00010e6f4>] arm_kprobe+0x34/0x50
[<ffffffc000110374>] register_kprobe+0x4cc/0x5b8
[<ffffffbffc002038>] kprobe_init+0x38/0x7c [kprobe_example]
[<ffffffc000084240>] do_one_initcall+0x90/0x1b0
[<ffffffc00061c498>] do_init_module+0x6c/0x1cc
[<ffffffc0000fd0c0>] load_module+0x17f8/0x1db0
[<ffffffc0000fd8cc>] SyS_finit_module+0xb4/0xc8

Convert patch_lock to raw loc kto avoid this issue.

Although the problem is found on rt kernel, the fix should be applicable to
mainline kernel too.

Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Yang Shi <yang.shi@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
nkskjames pushed a commit to nkskjames/linux that referenced this pull request Jan 13, 2016
When freqdomain_cpus attribute is read from an offlined cpu, it will
cause crash. This change prevents calling cpufreq_show_cpus when
policy driver_data is NULL.

Crash info:

[  170.814949] BUG: unable to handle kernel NULL pointer dereference at 0000000000000018
[  170.814990] IP: [<ffffffff813b2490>] _find_next_bit.part.0+0x10/0x70
[  170.815021] PGD 227d30067 PUD 229e56067 PMD 0
[  170.815043] Oops: 0000 [openbmc#2] SMP
[  170.816022] CPU: 3 PID: 3121 Comm: cat Tainted: G      D    OE   4.3.0-rc3+ openbmc#33
...
...
[  170.816657] Call Trace:
[  170.816672]  [<ffffffff813b2505>] ? find_next_bit+0x15/0x20
[  170.816696]  [<ffffffff8160e47c>] cpufreq_show_cpus+0x5c/0xd0
[  170.816722]  [<ffffffffa031a409>] show_freqdomain_cpus+0x19/0x20 [acpi_cpufreq]
[  170.816749]  [<ffffffff8160e65b>] show+0x3b/0x60
[  170.816769]  [<ffffffff8129b31c>] sysfs_kf_seq_show+0xbc/0x130
[  170.816793]  [<ffffffff81299be3>] kernfs_seq_show+0x23/0x30
[  170.816816]  [<ffffffff81240f2c>] seq_read+0xec/0x390
[  170.816837]  [<ffffffff8129a64a>] kernfs_fop_read+0x10a/0x160
[  170.816861]  [<ffffffff8121d9b7>] __vfs_read+0x37/0x100
[  170.816883]  [<ffffffff813217c0>] ? security_file_permission+0xa0/0xc0
[  170.816909]  [<ffffffff8121e2e3>] vfs_read+0x83/0x130
[  170.816930]  [<ffffffff8121f035>] SyS_read+0x55/0xc0
...
...
[  170.817185] ---[ end trace bc6eadf82b2b965a ]---

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: 4.2+ <stable@vger.kernel.org> # 4.2+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
nkskjames pushed a commit to nkskjames/linux that referenced this pull request Jan 13, 2016
…_BH() in preemptible context.

[ Upstream commit 44f49dd ]

Fixes the following kernel BUG :

BUG: using __this_cpu_add() in preemptible [00000000] code: bash/2758
caller is __this_cpu_preempt_check+0x13/0x15
CPU: 0 PID: 2758 Comm: bash Tainted: P           O   3.18.19 openbmc#2
 ffffffff8170eaca ffff880110d1b788 ffffffff81482b2a 0000000000000000
 0000000000000000 ffff880110d1b7b8 ffffffff812010ae ffff880007cab800
 ffff88001a060800 ffff88013a899108 ffff880108b84240 ffff880110d1b7c8
Call Trace:
[<ffffffff81482b2a>] dump_stack+0x52/0x80
[<ffffffff812010ae>] check_preemption_disabled+0xce/0xe1
[<ffffffff812010d4>] __this_cpu_preempt_check+0x13/0x15
[<ffffffff81419d60>] ipmr_queue_xmit+0x647/0x70c
[<ffffffff8141a154>] ip_mr_forward+0x32f/0x34e
[<ffffffff8141af76>] ip_mroute_setsockopt+0xe03/0x108c
[<ffffffff810553fc>] ? get_parent_ip+0x11/0x42
[<ffffffff810e6974>] ? pollwake+0x4d/0x51
[<ffffffff81058ac0>] ? default_wake_function+0x0/0xf
[<ffffffff810553fc>] ? get_parent_ip+0x11/0x42
[<ffffffff810613d9>] ? __wake_up_common+0x45/0x77
[<ffffffff81486ea9>] ? _raw_spin_unlock_irqrestore+0x1d/0x32
[<ffffffff810618bc>] ? __wake_up_sync_key+0x4a/0x53
[<ffffffff8139a519>] ? sock_def_readable+0x71/0x75
[<ffffffff813dd226>] do_ip_setsockopt+0x9d/0xb55
[<ffffffff81429818>] ? unix_seqpacket_sendmsg+0x3f/0x41
[<ffffffff813963fe>] ? sock_sendmsg+0x6d/0x86
[<ffffffff813959d4>] ? sockfd_lookup_light+0x12/0x5d
[<ffffffff8139650a>] ? SyS_sendto+0xf3/0x11b
[<ffffffff810d5738>] ? new_sync_read+0x82/0xaa
[<ffffffff813ddd19>] compat_ip_setsockopt+0x3b/0x99
[<ffffffff813fb24a>] compat_raw_setsockopt+0x11/0x32
[<ffffffff81399052>] compat_sock_common_setsockopt+0x18/0x1f
[<ffffffff813c4d05>] compat_SyS_setsockopt+0x1a9/0x1cf
[<ffffffff813c4149>] compat_SyS_socketcall+0x180/0x1e3
[<ffffffff81488ea1>] cstar_dispatch+0x7/0x1e

Signed-off-by: Ani Sinha <ani@arista.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amboar pushed a commit that referenced this pull request Jun 13, 2024
[ Upstream commit 3ebc46c ]

In dctcp_update_alpha(), we use a module parameter dctcp_shift_g
as follows:

  alpha -= min_not_zero(alpha, alpha >> dctcp_shift_g);
  ...
  delivered_ce <<= (10 - dctcp_shift_g);

It seems syzkaller started fuzzing module parameters and triggered
shift-out-of-bounds [0] by setting 100 to dctcp_shift_g:

  memcpy((void*)0x20000080,
         "/sys/module/tcp_dctcp/parameters/dctcp_shift_g\000", 47);
  res = syscall(__NR_openat, /*fd=*/0xffffffffffffff9cul, /*file=*/0x20000080ul,
                /*flags=*/2ul, /*mode=*/0ul);
  memcpy((void*)0x20000000, "100\000", 4);
  syscall(__NR_write, /*fd=*/r[0], /*val=*/0x20000000ul, /*len=*/4ul);

Let's limit the max value of dctcp_shift_g by param_set_uint_minmax().

With this patch:

  # echo 10 > /sys/module/tcp_dctcp/parameters/dctcp_shift_g
  # cat /sys/module/tcp_dctcp/parameters/dctcp_shift_g
  10
  # echo 11 > /sys/module/tcp_dctcp/parameters/dctcp_shift_g
  -bash: echo: write error: Invalid argument

[0]:
UBSAN: shift-out-of-bounds in net/ipv4/tcp_dctcp.c:143:12
shift exponent 100 is too large for 32-bit type 'u32' (aka 'unsigned int')
CPU: 0 PID: 8083 Comm: syz-executor345 Not tainted 6.9.0-05151-g1b294a1f3561 #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.13.0-1ubuntu1.1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x201/0x300 lib/dump_stack.c:114
 ubsan_epilogue lib/ubsan.c:231 [inline]
 __ubsan_handle_shift_out_of_bounds+0x346/0x3a0 lib/ubsan.c:468
 dctcp_update_alpha+0x540/0x570 net/ipv4/tcp_dctcp.c:143
 tcp_in_ack_event net/ipv4/tcp_input.c:3802 [inline]
 tcp_ack+0x17b1/0x3bc0 net/ipv4/tcp_input.c:3948
 tcp_rcv_state_process+0x57a/0x2290 net/ipv4/tcp_input.c:6711
 tcp_v4_do_rcv+0x764/0xc40 net/ipv4/tcp_ipv4.c:1937
 sk_backlog_rcv include/net/sock.h:1106 [inline]
 __release_sock+0x20f/0x350 net/core/sock.c:2983
 release_sock+0x61/0x1f0 net/core/sock.c:3549
 mptcp_subflow_shutdown+0x3d0/0x620 net/mptcp/protocol.c:2907
 mptcp_check_send_data_fin+0x225/0x410 net/mptcp/protocol.c:2976
 __mptcp_close+0x238/0xad0 net/mptcp/protocol.c:3072
 mptcp_close+0x2a/0x1a0 net/mptcp/protocol.c:3127
 inet_release+0x190/0x1f0 net/ipv4/af_inet.c:437
 __sock_release net/socket.c:659 [inline]
 sock_close+0xc0/0x240 net/socket.c:1421
 __fput+0x41b/0x890 fs/file_table.c:422
 task_work_run+0x23b/0x300 kernel/task_work.c:180
 exit_task_work include/linux/task_work.h:38 [inline]
 do_exit+0x9c8/0x2540 kernel/exit.c:878
 do_group_exit+0x201/0x2b0 kernel/exit.c:1027
 __do_sys_exit_group kernel/exit.c:1038 [inline]
 __se_sys_exit_group kernel/exit.c:1036 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1036
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xe4/0x240 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x67/0x6f
RIP: 0033:0x7f6c2b5005b6
Code: Unable to access opcode bytes at 0x7f6c2b50058c.
RSP: 002b:00007ffe883eb948 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f6c2b5862f0 RCX: 00007f6c2b5005b6
RDX: 0000000000000001 RSI: 000000000000003c RDI: 0000000000000001
RBP: 0000000000000001 R08: 00000000000000e7 R09: ffffffffffffffc0
R10: 0000000000000006 R11: 0000000000000246 R12: 00007f6c2b5862f0
R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000001
 </TASK>

Reported-by: syzkaller <syzkaller@googlegroups.com>
Reported-by: Yue Sun <samsun1006219@gmail.com>
Reported-by: xingwei lee <xrivendell7@gmail.com>
Closes: https://lore.kernel.org/netdev/CAEkJfYNJM=cw-8x7_Vmj1J6uYVCWMbbvD=EFmDPVBGpTsqOxEA@mail.gmail.com/
Fixes: e3118e8 ("net: tcp: add DCTCP congestion control algorithm")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20240517091626.32772-1-kuniyu@amazon.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
amboar pushed a commit that referenced this pull request Jun 17, 2024
commit 9d274c1 upstream.

We have been seeing crashes on duplicate keys in
btrfs_set_item_key_safe():

  BTRFS critical (device vdb): slot 4 key (450 108 8192) new key (450 108 8192)
  ------------[ cut here ]------------
  kernel BUG at fs/btrfs/ctree.c:2620!
  invalid opcode: 0000 [#1] PREEMPT SMP PTI
  CPU: 0 PID: 3139 Comm: xfs_io Kdump: loaded Not tainted 6.9.0 #6
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-2.fc40 04/01/2014
  RIP: 0010:btrfs_set_item_key_safe+0x11f/0x290 [btrfs]

With the following stack trace:

  #0  btrfs_set_item_key_safe (fs/btrfs/ctree.c:2620:4)
  #1  btrfs_drop_extents (fs/btrfs/file.c:411:4)
  #2  log_one_extent (fs/btrfs/tree-log.c:4732:9)
  #3  btrfs_log_changed_extents (fs/btrfs/tree-log.c:4955:9)
  #4  btrfs_log_inode (fs/btrfs/tree-log.c:6626:9)
  #5  btrfs_log_inode_parent (fs/btrfs/tree-log.c:7070:8)
  #6  btrfs_log_dentry_safe (fs/btrfs/tree-log.c:7171:8)
  #7  btrfs_sync_file (fs/btrfs/file.c:1933:8)
  #8  vfs_fsync_range (fs/sync.c:188:9)
  #9  vfs_fsync (fs/sync.c:202:9)
  #10 do_fsync (fs/sync.c:212:9)
  #11 __do_sys_fdatasync (fs/sync.c:225:9)
  #12 __se_sys_fdatasync (fs/sync.c:223:1)
  #13 __x64_sys_fdatasync (fs/sync.c:223:1)
  #14 do_syscall_x64 (arch/x86/entry/common.c:52:14)
  #15 do_syscall_64 (arch/x86/entry/common.c:83:7)
  #16 entry_SYSCALL_64+0xaf/0x14c (arch/x86/entry/entry_64.S:121)

So we're logging a changed extent from fsync, which is splitting an
extent in the log tree. But this split part already exists in the tree,
triggering the BUG().

This is the state of the log tree at the time of the crash, dumped with
drgn (https://github.com/osandov/drgn/blob/main/contrib/btrfs_tree.py)
to get more details than btrfs_print_leaf() gives us:

  >>> print_extent_buffer(prog.crashed_thread().stack_trace()[0]["eb"])
  leaf 33439744 level 0 items 72 generation 9 owner 18446744073709551610
  leaf 33439744 flags 0x100000000000000
  fs uuid e5bd3946-400c-4223-8923-190ef1f18677
  chunk uuid d58cb17e-6d02-494a-829a-18b7d8a399da
          item 0 key (450 INODE_ITEM 0) itemoff 16123 itemsize 160
                  generation 7 transid 9 size 8192 nbytes 8473563889606862198
                  block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0
                  sequence 204 flags 0x10(PREALLOC)
                  atime 1716417703.220000000 (2024-05-22 15:41:43)
                  ctime 1716417704.983333333 (2024-05-22 15:41:44)
                  mtime 1716417704.983333333 (2024-05-22 15:41:44)
                  otime 17592186044416.000000000 (559444-03-08 01:40:16)
          item 1 key (450 INODE_REF 256) itemoff 16110 itemsize 13
                  index 195 namelen 3 name: 193
          item 2 key (450 XATTR_ITEM 1640047104) itemoff 16073 itemsize 37
                  location key (0 UNKNOWN.0 0) type XATTR
                  transid 7 data_len 1 name_len 6
                  name: user.a
                  data a
          item 3 key (450 EXTENT_DATA 0) itemoff 16020 itemsize 53
                  generation 9 type 1 (regular)
                  extent data disk byte 303144960 nr 12288
                  extent data offset 0 nr 4096 ram 12288
                  extent compression 0 (none)
          item 4 key (450 EXTENT_DATA 4096) itemoff 15967 itemsize 53
                  generation 9 type 2 (prealloc)
                  prealloc data disk byte 303144960 nr 12288
                  prealloc data offset 4096 nr 8192
          item 5 key (450 EXTENT_DATA 8192) itemoff 15914 itemsize 53
                  generation 9 type 2 (prealloc)
                  prealloc data disk byte 303144960 nr 12288
                  prealloc data offset 8192 nr 4096
  ...

So the real problem happened earlier: notice that items 4 (4k-12k) and 5
(8k-12k) overlap. Both are prealloc extents. Item 4 straddles i_size and
item 5 starts at i_size.

Here is the state of the filesystem tree at the time of the crash:

  >>> root = prog.crashed_thread().stack_trace()[2]["inode"].root
  >>> ret, nodes, slots = btrfs_search_slot(root, BtrfsKey(450, 0, 0))
  >>> print_extent_buffer(nodes[0])
  leaf 30425088 level 0 items 184 generation 9 owner 5
  leaf 30425088 flags 0x100000000000000
  fs uuid e5bd3946-400c-4223-8923-190ef1f18677
  chunk uuid d58cb17e-6d02-494a-829a-18b7d8a399da
  	...
          item 179 key (450 INODE_ITEM 0) itemoff 4907 itemsize 160
                  generation 7 transid 7 size 4096 nbytes 12288
                  block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0
                  sequence 6 flags 0x10(PREALLOC)
                  atime 1716417703.220000000 (2024-05-22 15:41:43)
                  ctime 1716417703.220000000 (2024-05-22 15:41:43)
                  mtime 1716417703.220000000 (2024-05-22 15:41:43)
                  otime 1716417703.220000000 (2024-05-22 15:41:43)
          item 180 key (450 INODE_REF 256) itemoff 4894 itemsize 13
                  index 195 namelen 3 name: 193
          item 181 key (450 XATTR_ITEM 1640047104) itemoff 4857 itemsize 37
                  location key (0 UNKNOWN.0 0) type XATTR
                  transid 7 data_len 1 name_len 6
                  name: user.a
                  data a
          item 182 key (450 EXTENT_DATA 0) itemoff 4804 itemsize 53
                  generation 9 type 1 (regular)
                  extent data disk byte 303144960 nr 12288
                  extent data offset 0 nr 8192 ram 12288
                  extent compression 0 (none)
          item 183 key (450 EXTENT_DATA 8192) itemoff 4751 itemsize 53
                  generation 9 type 2 (prealloc)
                  prealloc data disk byte 303144960 nr 12288
                  prealloc data offset 8192 nr 4096

Item 5 in the log tree corresponds to item 183 in the filesystem tree,
but nothing matches item 4. Furthermore, item 183 is the last item in
the leaf.

btrfs_log_prealloc_extents() is responsible for logging prealloc extents
beyond i_size. It first truncates any previously logged prealloc extents
that start beyond i_size. Then, it walks the filesystem tree and copies
the prealloc extent items to the log tree.

If it hits the end of a leaf, then it calls btrfs_next_leaf(), which
unlocks the tree and does another search. However, while the filesystem
tree is unlocked, an ordered extent completion may modify the tree. In
particular, it may insert an extent item that overlaps with an extent
item that was already copied to the log tree.

This may manifest in several ways depending on the exact scenario,
including an EEXIST error that is silently translated to a full sync,
overlapping items in the log tree, or this crash. This particular crash
is triggered by the following sequence of events:

- Initially, the file has i_size=4k, a regular extent from 0-4k, and a
  prealloc extent beyond i_size from 4k-12k. The prealloc extent item is
  the last item in its B-tree leaf.
- The file is fsync'd, which copies its inode item and both extent items
  to the log tree.
- An xattr is set on the file, which sets the
  BTRFS_INODE_COPY_EVERYTHING flag.
- The range 4k-8k in the file is written using direct I/O. i_size is
  extended to 8k, but the ordered extent is still in flight.
- The file is fsync'd. Since BTRFS_INODE_COPY_EVERYTHING is set, this
  calls copy_inode_items_to_log(), which calls
  btrfs_log_prealloc_extents().
- btrfs_log_prealloc_extents() finds the 4k-12k prealloc extent in the
  filesystem tree. Since it starts before i_size, it skips it. Since it
  is the last item in its B-tree leaf, it calls btrfs_next_leaf().
- btrfs_next_leaf() unlocks the path.
- The ordered extent completion runs, which converts the 4k-8k part of
  the prealloc extent to written and inserts the remaining prealloc part
  from 8k-12k.
- btrfs_next_leaf() does a search and finds the new prealloc extent
  8k-12k.
- btrfs_log_prealloc_extents() copies the 8k-12k prealloc extent into
  the log tree. Note that it overlaps with the 4k-12k prealloc extent
  that was copied to the log tree by the first fsync.
- fsync calls btrfs_log_changed_extents(), which tries to log the 4k-8k
  extent that was written.
- This tries to drop the range 4k-8k in the log tree, which requires
  adjusting the start of the 4k-12k prealloc extent in the log tree to
  8k.
- btrfs_set_item_key_safe() sees that there is already an extent
  starting at 8k in the log tree and calls BUG().

Fix this by detecting when we're about to insert an overlapping file
extent item in the log tree and truncating the part that would overlap.

CC: stable@vger.kernel.org # 6.1+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amboar pushed a commit that referenced this pull request Jun 24, 2024
commit 22f0081 upstream.

The syzbot fuzzer found that the interrupt-URB completion callback in
the cdc-wdm driver was taking too long, and the driver's immediate
resubmission of interrupt URBs with -EPROTO status combined with the
dummy-hcd emulation to cause a CPU lockup:

cdc_wdm 1-1:1.0: nonzero urb status received: -71
cdc_wdm 1-1:1.0: wdm_int_callback - 0 bytes
watchdog: BUG: soft lockup - CPU#0 stuck for 26s! [syz-executor782:6625]
CPU#0 Utilization every 4s during lockup:
	#1:  98% system,	  0% softirq,	  3% hardirq,	  0% idle
	#2:  98% system,	  0% softirq,	  3% hardirq,	  0% idle
	#3:  98% system,	  0% softirq,	  3% hardirq,	  0% idle
	#4:  98% system,	  0% softirq,	  3% hardirq,	  0% idle
	#5:  98% system,	  1% softirq,	  3% hardirq,	  0% idle
Modules linked in:
irq event stamp: 73096
hardirqs last  enabled at (73095): [<ffff80008037bc00>] console_emit_next_record kernel/printk/printk.c:2935 [inline]
hardirqs last  enabled at (73095): [<ffff80008037bc00>] console_flush_all+0x650/0xb74 kernel/printk/printk.c:2994
hardirqs last disabled at (73096): [<ffff80008af10b00>] __el1_irq arch/arm64/kernel/entry-common.c:533 [inline]
hardirqs last disabled at (73096): [<ffff80008af10b00>] el1_interrupt+0x24/0x68 arch/arm64/kernel/entry-common.c:551
softirqs last  enabled at (73048): [<ffff8000801ea530>] softirq_handle_end kernel/softirq.c:400 [inline]
softirqs last  enabled at (73048): [<ffff8000801ea530>] handle_softirqs+0xa60/0xc34 kernel/softirq.c:582
softirqs last disabled at (73043): [<ffff800080020de8>] __do_softirq+0x14/0x20 kernel/softirq.c:588
CPU: 0 PID: 6625 Comm: syz-executor782 Tainted: G        W          6.10.0-rc2-syzkaller-g8867bbd4a056 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024

Testing showed that the problem did not occur if the two error
messages -- the first two lines above -- were removed; apparently adding
material to the kernel log takes a surprisingly large amount of time.

In any case, the best approach for preventing these lockups and to
avoid spamming the log with thousands of error messages per second is
to ratelimit the two dev_err() calls.  Therefore we replace them with
dev_err_ratelimited().

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Suggested-by: Greg KH <gregkh@linuxfoundation.org>
Reported-and-tested-by: syzbot+5f996b83575ef4058638@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/linux-usb/00000000000073d54b061a6a1c65@google.com/
Reported-and-tested-by: syzbot+1b2abad17596ad03dcff@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/linux-usb/000000000000f45085061aa9b37e@google.com/
Fixes: 9908a32 ("USB: remove err() macro from usb class drivers")
Link: https://lore.kernel.org/linux-usb/40dfa45b-5f21-4eef-a8c1-51a2f320e267@rowland.harvard.edu/
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/29855215-52f5-4385-b058-91f42c2bee18@rowland.harvard.edu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amboar pushed a commit that referenced this pull request Jun 24, 2024
commit c0a4009 upstream.

Synchronize the dev->driver usage in really_probe() and dev_uevent().
These can run in different threads, what can result in the following
race condition for dev->driver uninitialization:

Thread #1:
==========

really_probe() {
...
probe_failed:
...
device_unbind_cleanup(dev) {
    ...
    dev->driver = NULL;   // <= Failed probe sets dev->driver to NULL
    ...
    }
...
}

Thread #2:
==========

dev_uevent() {
...
if (dev->driver)
      // If dev->driver is NULLed from really_probe() from here on,
      // after above check, the system crashes
      add_uevent_var(env, "DRIVER=%s", dev->driver->name);
...
}

really_probe() holds the lock, already. So nothing needs to be done
there. dev_uevent() is called with lock held, often, too. But not
always. What implies that we can't add any locking in dev_uevent()
itself. So fix this race by adding the lock to the non-protected
path. This is the path where above race is observed:

 dev_uevent+0x235/0x380
 uevent_show+0x10c/0x1f0  <= Add lock here
 dev_attr_show+0x3a/0xa0
 sysfs_kf_seq_show+0x17c/0x250
 kernfs_seq_show+0x7c/0x90
 seq_read_iter+0x2d7/0x940
 kernfs_fop_read_iter+0xc6/0x310
 vfs_read+0x5bc/0x6b0
 ksys_read+0xeb/0x1b0
 __x64_sys_read+0x42/0x50
 x64_sys_call+0x27ad/0x2d30
 do_syscall_64+0xcd/0x1d0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Similar cases are reported by syzkaller in

https://syzkaller.appspot.com/bug?extid=ffa8143439596313a85a

But these are regarding the *initialization* of dev->driver

dev->driver = drv;

As this switches dev->driver to non-NULL these reports can be considered
to be false-positives (which should be "fixed" by this commit, as well,
though).

The same issue was reported and tried to be fixed back in 2015 in

https://lore.kernel.org/lkml/1421259054-2574-1-git-send-email-a.sangwan@samsung.com/

already.

Fixes: 239378f ("Driver core: add uevent vars for devices of a class")
Cc: stable <stable@kernel.org>
Cc: syzbot+ffa8143439596313a85a@syzkaller.appspotmail.com
Cc: Ashish Sangwan <a.sangwan@samsung.com>
Cc: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Dirk Behme <dirk.behme@de.bosch.com>
Link: https://lore.kernel.org/r/20240513050634.3964461-1-dirk.behme@de.bosch.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amboar pushed a commit that referenced this pull request Jun 28, 2024
[ Upstream commit f1e197a ]

trace_drop_common() is called with preemption disabled, and it acquires
a spin_lock. This is problematic for RT kernels because spin_locks are
sleeping locks in this configuration, which causes the following splat:

BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:48
in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 449, name: rcuc/47
preempt_count: 1, expected: 0
RCU nest depth: 2, expected: 2
5 locks held by rcuc/47/449:
 #0: ff1100086ec30a60 ((softirq_ctrl.lock)){+.+.}-{2:2}, at: __local_bh_disable_ip+0x105/0x210
 #1: ffffffffb394a280 (rcu_read_lock){....}-{1:2}, at: rt_spin_lock+0xbf/0x130
 #2: ffffffffb394a280 (rcu_read_lock){....}-{1:2}, at: __local_bh_disable_ip+0x11c/0x210
 #3: ffffffffb394a160 (rcu_callback){....}-{0:0}, at: rcu_do_batch+0x360/0xc70
 #4: ff1100086ee07520 (&data->lock){+.+.}-{2:2}, at: trace_drop_common.constprop.0+0xb5/0x290
irq event stamp: 139909
hardirqs last  enabled at (139908): [<ffffffffb1df2b33>] _raw_spin_unlock_irqrestore+0x63/0x80
hardirqs last disabled at (139909): [<ffffffffb19bd03d>] trace_drop_common.constprop.0+0x26d/0x290
softirqs last  enabled at (139892): [<ffffffffb07a1083>] __local_bh_enable_ip+0x103/0x170
softirqs last disabled at (139898): [<ffffffffb0909b33>] rcu_cpu_kthread+0x93/0x1f0
Preemption disabled at:
[<ffffffffb1de786b>] rt_mutex_slowunlock+0xab/0x2e0
CPU: 47 PID: 449 Comm: rcuc/47 Not tainted 6.9.0-rc2-rt1+ #7
Hardware name: Dell Inc. PowerEdge R650/0Y2G81, BIOS 1.6.5 04/15/2022
Call Trace:
 <TASK>
 dump_stack_lvl+0x8c/0xd0
 dump_stack+0x14/0x20
 __might_resched+0x21e/0x2f0
 rt_spin_lock+0x5e/0x130
 ? trace_drop_common.constprop.0+0xb5/0x290
 ? skb_queue_purge_reason.part.0+0x1bf/0x230
 trace_drop_common.constprop.0+0xb5/0x290
 ? preempt_count_sub+0x1c/0xd0
 ? _raw_spin_unlock_irqrestore+0x4a/0x80
 ? __pfx_trace_drop_common.constprop.0+0x10/0x10
 ? rt_mutex_slowunlock+0x26a/0x2e0
 ? skb_queue_purge_reason.part.0+0x1bf/0x230
 ? __pfx_rt_mutex_slowunlock+0x10/0x10
 ? skb_queue_purge_reason.part.0+0x1bf/0x230
 trace_kfree_skb_hit+0x15/0x20
 trace_kfree_skb+0xe9/0x150
 kfree_skb_reason+0x7b/0x110
 skb_queue_purge_reason.part.0+0x1bf/0x230
 ? __pfx_skb_queue_purge_reason.part.0+0x10/0x10
 ? mark_lock.part.0+0x8a/0x520
...

trace_drop_common() also disables interrupts, but this is a minor issue
because we could easily replace it with a local_lock.

Replace the spin_lock with raw_spin_lock to avoid sleeping in atomic
context.

Signed-off-by: Wander Lairson Costa <wander@redhat.com>
Reported-by: Hu Chunyu <chuhu@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
amboar pushed a commit that referenced this pull request Jun 28, 2024
[ Upstream commit af0cb3f ]

Xiumei and Christoph reported the following lockdep splat, complaining of
the qdisc root lock being taken twice:

 ============================================
 WARNING: possible recursive locking detected
 6.7.0-rc3+ torvalds#598 Not tainted
 --------------------------------------------
 swapper/2/0 is trying to acquire lock:
 ffff888177190110 (&sch->q.lock){+.-.}-{2:2}, at: __dev_queue_xmit+0x1560/0x2e70

 but task is already holding lock:
 ffff88811995a110 (&sch->q.lock){+.-.}-{2:2}, at: __dev_queue_xmit+0x1560/0x2e70

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

        CPU0
        ----
   lock(&sch->q.lock);
   lock(&sch->q.lock);

  *** DEADLOCK ***

  May be due to missing lock nesting notation

 5 locks held by swapper/2/0:
  #0: ffff888135a09d98 ((&in_dev->mr_ifc_timer)){+.-.}-{0:0}, at: call_timer_fn+0x11a/0x510
  #1: ffffffffaaee5260 (rcu_read_lock){....}-{1:2}, at: ip_finish_output2+0x2c0/0x1ed0
  #2: ffffffffaaee5200 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x209/0x2e70
  #3: ffff88811995a110 (&sch->q.lock){+.-.}-{2:2}, at: __dev_queue_xmit+0x1560/0x2e70
  #4: ffffffffaaee5200 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x209/0x2e70

 stack backtrace:
 CPU: 2 PID: 0 Comm: swapper/2 Not tainted 6.7.0-rc3+ torvalds#598
 Hardware name: Red Hat KVM, BIOS 1.13.0-2.module+el8.3.0+7353+9de0a3cc 04/01/2014
 Call Trace:
  <IRQ>
  dump_stack_lvl+0x4a/0x80
  __lock_acquire+0xfdd/0x3150
  lock_acquire+0x1ca/0x540
  _raw_spin_lock+0x34/0x80
  __dev_queue_xmit+0x1560/0x2e70
  tcf_mirred_act+0x82e/0x1260 [act_mirred]
  tcf_action_exec+0x161/0x480
  tcf_classify+0x689/0x1170
  prio_enqueue+0x316/0x660 [sch_prio]
  dev_qdisc_enqueue+0x46/0x220
  __dev_queue_xmit+0x1615/0x2e70
  ip_finish_output2+0x1218/0x1ed0
  __ip_finish_output+0x8b3/0x1350
  ip_output+0x163/0x4e0
  igmp_ifc_timer_expire+0x44b/0x930
  call_timer_fn+0x1a2/0x510
  run_timer_softirq+0x54d/0x11a0
  __do_softirq+0x1b3/0x88f
  irq_exit_rcu+0x18f/0x1e0
  sysvec_apic_timer_interrupt+0x6f/0x90
  </IRQ>

This happens when TC does a mirred egress redirect from the root qdisc of
device A to the root qdisc of device B. As long as these two locks aren't
protecting the same qdisc, they can be acquired in chain: add a per-qdisc
lockdep key to silence false warnings.
This dynamic key should safely replace the static key we have in sch_htb:
it was added to allow enqueueing to the device "direct qdisc" while still
holding the qdisc root lock.

v2: don't use static keys anymore in HTB direct qdiscs (thanks Eric Dumazet)

CC: Maxim Mikityanskiy <maxim@isovalent.com>
CC: Xiumei Mu <xmu@redhat.com>
Reported-by: Christoph Paasch <cpaasch@apple.com>
Closes: multipath-tcp/mptcp_net-next#451
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Link: https://lore.kernel.org/r/7dc06d6158f72053cf877a82e2a7a5bd23692faa.1713448007.git.dcaratti@redhat.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
amboar pushed a commit that referenced this pull request Jun 28, 2024
[ Upstream commit f6944d4 ]

Lockdep reports the below circular locking dependency issue.  The
mmap_lock acquisition while holding pci_bus_sem is due to the use of
copy_to_user() from within a pci_walk_bus() callback.

Building the devices array directly into the user buffer is only for
convenience.  Instead we can allocate a local buffer for the array,
bounded by the number of devices on the bus/slot, fill the device
information into this local buffer, then copy it into the user buffer
outside the bus walk callback.

======================================================
WARNING: possible circular locking dependency detected
6.9.0-rc5+ #39 Not tainted
------------------------------------------------------
CPU 0/KVM/4113 is trying to acquire lock:
ffff99a609ee18a8 (&vdev->vma_lock){+.+.}-{4:4}, at: vfio_pci_mmap_fault+0x35/0x1a0 [vfio_pci_core]

but task is already holding lock:
ffff99a243a052a0 (&mm->mmap_lock){++++}-{4:4}, at: vaddr_get_pfns+0x3f/0x170 [vfio_iommu_type1]

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #3 (&mm->mmap_lock){++++}-{4:4}:
       __lock_acquire+0x4e4/0xb90
       lock_acquire+0xbc/0x2d0
       __might_fault+0x5c/0x80
       _copy_to_user+0x1e/0x60
       vfio_pci_fill_devs+0x9f/0x130 [vfio_pci_core]
       vfio_pci_walk_wrapper+0x45/0x60 [vfio_pci_core]
       __pci_walk_bus+0x6b/0xb0
       vfio_pci_ioctl_get_pci_hot_reset_info+0x10b/0x1d0 [vfio_pci_core]
       vfio_pci_core_ioctl+0x1cb/0x400 [vfio_pci_core]
       vfio_device_fops_unl_ioctl+0x7e/0x140 [vfio]
       __x64_sys_ioctl+0x8a/0xc0
       do_syscall_64+0x8d/0x170
       entry_SYSCALL_64_after_hwframe+0x76/0x7e

-> #2 (pci_bus_sem){++++}-{4:4}:
       __lock_acquire+0x4e4/0xb90
       lock_acquire+0xbc/0x2d0
       down_read+0x3e/0x160
       pci_bridge_wait_for_secondary_bus.part.0+0x33/0x2d0
       pci_reset_bus+0xdd/0x160
       vfio_pci_dev_set_hot_reset+0x256/0x270 [vfio_pci_core]
       vfio_pci_ioctl_pci_hot_reset_groups+0x1a3/0x280 [vfio_pci_core]
       vfio_pci_core_ioctl+0x3b5/0x400 [vfio_pci_core]
       vfio_device_fops_unl_ioctl+0x7e/0x140 [vfio]
       __x64_sys_ioctl+0x8a/0xc0
       do_syscall_64+0x8d/0x170
       entry_SYSCALL_64_after_hwframe+0x76/0x7e

-> #1 (&vdev->memory_lock){+.+.}-{4:4}:
       __lock_acquire+0x4e4/0xb90
       lock_acquire+0xbc/0x2d0
       down_write+0x3b/0xc0
       vfio_pci_zap_and_down_write_memory_lock+0x1c/0x30 [vfio_pci_core]
       vfio_basic_config_write+0x281/0x340 [vfio_pci_core]
       vfio_config_do_rw+0x1fa/0x300 [vfio_pci_core]
       vfio_pci_config_rw+0x75/0xe50 [vfio_pci_core]
       vfio_pci_rw+0xea/0x1a0 [vfio_pci_core]
       vfs_write+0xea/0x520
       __x64_sys_pwrite64+0x90/0xc0
       do_syscall_64+0x8d/0x170
       entry_SYSCALL_64_after_hwframe+0x76/0x7e

-> #0 (&vdev->vma_lock){+.+.}-{4:4}:
       check_prev_add+0xeb/0xcc0
       validate_chain+0x465/0x530
       __lock_acquire+0x4e4/0xb90
       lock_acquire+0xbc/0x2d0
       __mutex_lock+0x97/0xde0
       vfio_pci_mmap_fault+0x35/0x1a0 [vfio_pci_core]
       __do_fault+0x31/0x160
       do_pte_missing+0x65/0x3b0
       __handle_mm_fault+0x303/0x720
       handle_mm_fault+0x10f/0x460
       fixup_user_fault+0x7f/0x1f0
       follow_fault_pfn+0x66/0x1c0 [vfio_iommu_type1]
       vaddr_get_pfns+0xf2/0x170 [vfio_iommu_type1]
       vfio_pin_pages_remote+0x348/0x4e0 [vfio_iommu_type1]
       vfio_pin_map_dma+0xd2/0x330 [vfio_iommu_type1]
       vfio_dma_do_map+0x2c0/0x440 [vfio_iommu_type1]
       vfio_iommu_type1_ioctl+0xc5/0x1d0 [vfio_iommu_type1]
       __x64_sys_ioctl+0x8a/0xc0
       do_syscall_64+0x8d/0x170
       entry_SYSCALL_64_after_hwframe+0x76/0x7e

other info that might help us debug this:

Chain exists of:
  &vdev->vma_lock --> pci_bus_sem --> &mm->mmap_lock

 Possible unsafe locking scenario:

block dm-0: the capability attribute has been deprecated.
       CPU0                    CPU1
       ----                    ----
  rlock(&mm->mmap_lock);
                               lock(pci_bus_sem);
                               lock(&mm->mmap_lock);
  lock(&vdev->vma_lock);

 *** DEADLOCK ***

2 locks held by CPU 0/KVM/4113:
 #0: ffff99a25f294888 (&iommu->lock#2){+.+.}-{4:4}, at: vfio_dma_do_map+0x60/0x440 [vfio_iommu_type1]
 #1: ffff99a243a052a0 (&mm->mmap_lock){++++}-{4:4}, at: vaddr_get_pfns+0x3f/0x170 [vfio_iommu_type1]

stack backtrace:
CPU: 1 PID: 4113 Comm: CPU 0/KVM Not tainted 6.9.0-rc5+ #39
Hardware name: Dell Inc. PowerEdge T640/04WYPY, BIOS 2.15.1 06/16/2022
Call Trace:
 <TASK>
 dump_stack_lvl+0x64/0xa0
 check_noncircular+0x131/0x150
 check_prev_add+0xeb/0xcc0
 ? add_chain_cache+0x10a/0x2f0
 ? __lock_acquire+0x4e4/0xb90
 validate_chain+0x465/0x530
 __lock_acquire+0x4e4/0xb90
 lock_acquire+0xbc/0x2d0
 ? vfio_pci_mmap_fault+0x35/0x1a0 [vfio_pci_core]
 ? lock_is_held_type+0x9a/0x110
 __mutex_lock+0x97/0xde0
 ? vfio_pci_mmap_fault+0x35/0x1a0 [vfio_pci_core]
 ? lock_acquire+0xbc/0x2d0
 ? vfio_pci_mmap_fault+0x35/0x1a0 [vfio_pci_core]
 ? find_held_lock+0x2b/0x80
 ? vfio_pci_mmap_fault+0x35/0x1a0 [vfio_pci_core]
 vfio_pci_mmap_fault+0x35/0x1a0 [vfio_pci_core]
 __do_fault+0x31/0x160
 do_pte_missing+0x65/0x3b0
 __handle_mm_fault+0x303/0x720
 handle_mm_fault+0x10f/0x460
 fixup_user_fault+0x7f/0x1f0
 follow_fault_pfn+0x66/0x1c0 [vfio_iommu_type1]
 vaddr_get_pfns+0xf2/0x170 [vfio_iommu_type1]
 vfio_pin_pages_remote+0x348/0x4e0 [vfio_iommu_type1]
 vfio_pin_map_dma+0xd2/0x330 [vfio_iommu_type1]
 vfio_dma_do_map+0x2c0/0x440 [vfio_iommu_type1]
 vfio_iommu_type1_ioctl+0xc5/0x1d0 [vfio_iommu_type1]
 __x64_sys_ioctl+0x8a/0xc0
 do_syscall_64+0x8d/0x170
 ? rcu_core+0x8d/0x250
 ? __lock_release+0x5e/0x160
 ? rcu_core+0x8d/0x250
 ? lock_release+0x5f/0x120
 ? sched_clock+0xc/0x30
 ? sched_clock_cpu+0xb/0x190
 ? irqtime_account_irq+0x40/0xc0
 ? __local_bh_enable+0x54/0x60
 ? __do_softirq+0x315/0x3ca
 ? lockdep_hardirqs_on_prepare.part.0+0x97/0x140
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f8300d0357b
Code: ff ff ff 85 c0 79 9b 49 c7 c4 ff ff ff ff 5b 5d 4c 89 e0 41 5c c3 66 0f 1f 84 00 00 00 00 00 f3 0f 1e fa b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 75 68 0f 00 f7 d8 64 89 01 48
RSP: 002b:00007f82ef3fb948 EFLAGS: 00000206 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f8300d0357b
RDX: 00007f82ef3fb990 RSI: 0000000000003b71 RDI: 0000000000000023
RBP: 00007f82ef3fb9c0 R08: 0000000000000000 R09: 0000561b7e0bcac2
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000200000000 R14: 0000381800000000 R15: 0000000000000000
 </TASK>

Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20240503143138.3562116-1-alex.williamson@redhat.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
amboar pushed a commit that referenced this pull request Jun 28, 2024
commit 6cd4a78 upstream.

It is possible to trigger a use-after-free by:
  * attaching an fentry probe to __sock_release() and the probe calling the
    bpf_get_socket_cookie() helper
  * running traceroute -I 1.1.1.1 on a freshly booted VM

A KASAN enabled kernel will log something like below (decoded and stripped):
==================================================================
BUG: KASAN: slab-use-after-free in __sock_gen_cookie (./arch/x86/include/asm/atomic64_64.h:15 ./include/linux/atomic/atomic-arch-fallback.h:2583 ./include/linux/atomic/atomic-instrumented.h:1611 net/core/sock_diag.c:29)
Read of size 8 at addr ffff888007110dd8 by task traceroute/299

CPU: 2 PID: 299 Comm: traceroute Tainted: G            E      6.10.0-rc2+ #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
dump_stack_lvl (lib/dump_stack.c:117 (discriminator 1))
print_report (mm/kasan/report.c:378 mm/kasan/report.c:488)
? __sock_gen_cookie (./arch/x86/include/asm/atomic64_64.h:15 ./include/linux/atomic/atomic-arch-fallback.h:2583 ./include/linux/atomic/atomic-instrumented.h:1611 net/core/sock_diag.c:29)
kasan_report (mm/kasan/report.c:603)
? __sock_gen_cookie (./arch/x86/include/asm/atomic64_64.h:15 ./include/linux/atomic/atomic-arch-fallback.h:2583 ./include/linux/atomic/atomic-instrumented.h:1611 net/core/sock_diag.c:29)
kasan_check_range (mm/kasan/generic.c:183 mm/kasan/generic.c:189)
__sock_gen_cookie (./arch/x86/include/asm/atomic64_64.h:15 ./include/linux/atomic/atomic-arch-fallback.h:2583 ./include/linux/atomic/atomic-instrumented.h:1611 net/core/sock_diag.c:29)
bpf_get_socket_ptr_cookie (./arch/x86/include/asm/preempt.h:94 ./include/linux/sock_diag.h:42 net/core/filter.c:5094 net/core/filter.c:5092)
bpf_prog_875642cf11f1d139___sock_release+0x6e/0x8e
bpf_trampoline_6442506592+0x47/0xaf
__sock_release (net/socket.c:652)
__sock_create (net/socket.c:1601)
...
Allocated by task 299 on cpu 2 at 78.328492s:
kasan_save_stack (mm/kasan/common.c:48)
kasan_save_track (mm/kasan/common.c:68)
__kasan_slab_alloc (mm/kasan/common.c:312 mm/kasan/common.c:338)
kmem_cache_alloc_noprof (mm/slub.c:3941 mm/slub.c:4000 mm/slub.c:4007)
sk_prot_alloc (net/core/sock.c:2075)
sk_alloc (net/core/sock.c:2134)
inet_create (net/ipv4/af_inet.c:327 net/ipv4/af_inet.c:252)
__sock_create (net/socket.c:1572)
__sys_socket (net/socket.c:1660 net/socket.c:1644 net/socket.c:1706)
__x64_sys_socket (net/socket.c:1718)
do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)

Freed by task 299 on cpu 2 at 78.328502s:
kasan_save_stack (mm/kasan/common.c:48)
kasan_save_track (mm/kasan/common.c:68)
kasan_save_free_info (mm/kasan/generic.c:582)
poison_slab_object (mm/kasan/common.c:242)
__kasan_slab_free (mm/kasan/common.c:256)
kmem_cache_free (mm/slub.c:4437 mm/slub.c:4511)
__sk_destruct (net/core/sock.c:2117 net/core/sock.c:2208)
inet_create (net/ipv4/af_inet.c:397 net/ipv4/af_inet.c:252)
__sock_create (net/socket.c:1572)
__sys_socket (net/socket.c:1660 net/socket.c:1644 net/socket.c:1706)
__x64_sys_socket (net/socket.c:1718)
do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)

Fix this by clearing the struct socket reference in sk_common_release() to cover
all protocol families create functions, which may already attached the
reference to the sk object with sock_init_data().

Fixes: c5dbb89 ("bpf: Expose bpf_get_socket_cookie to tracing programs")
Suggested-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Ignat Korchagin <ignat@cloudflare.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/netdev/20240613194047.36478-1-kuniyu@amazon.com/T/
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: D. Wythe <alibuda@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240617210205.67311-1-ignat@cloudflare.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amboar pushed a commit that referenced this pull request Jul 10, 2024
…play

[ Upstream commit d182575 ]

During inode logging (and log replay too), we are holding a transaction
handle and we often need to call btrfs_iget(), which will read an inode
from its subvolume btree if it's not loaded in memory and that results in
allocating an inode with GFP_KERNEL semantics at the btrfs_alloc_inode()
callback - and this may recurse into the filesystem in case we are under
memory pressure and attempt to commit the current transaction, resulting
in a deadlock since the logging (or log replay) task is holding a
transaction handle open.

Syzbot reported this with the following stack traces:

  WARNING: possible circular locking dependency detected
  6.10.0-rc2-syzkaller-00361-g061d1af7b030 #0 Not tainted
  ------------------------------------------------------
  syz-executor.1/9919 is trying to acquire lock:
  ffffffff8dd3aac0 (fs_reclaim){+.+.}-{0:0}, at: might_alloc include/linux/sched/mm.h:334 [inline]
  ffffffff8dd3aac0 (fs_reclaim){+.+.}-{0:0}, at: slab_pre_alloc_hook mm/slub.c:3891 [inline]
  ffffffff8dd3aac0 (fs_reclaim){+.+.}-{0:0}, at: slab_alloc_node mm/slub.c:3981 [inline]
  ffffffff8dd3aac0 (fs_reclaim){+.+.}-{0:0}, at: kmem_cache_alloc_lru_noprof+0x58/0x2f0 mm/slub.c:4020

  but task is already holding lock:
  ffff88804b569358 (&ei->log_mutex){+.+.}-{3:3}, at: btrfs_log_inode+0x39c/0x4660 fs/btrfs/tree-log.c:6481

  which lock already depends on the new lock.

  the existing dependency chain (in reverse order) is:

  -> #3 (&ei->log_mutex){+.+.}-{3:3}:
         __mutex_lock_common kernel/locking/mutex.c:608 [inline]
         __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752
         btrfs_log_inode+0x39c/0x4660 fs/btrfs/tree-log.c:6481
         btrfs_log_inode_parent+0x8cb/0x2a90 fs/btrfs/tree-log.c:7079
         btrfs_log_dentry_safe+0x59/0x80 fs/btrfs/tree-log.c:7180
         btrfs_sync_file+0x9c1/0xe10 fs/btrfs/file.c:1959
         vfs_fsync_range+0x141/0x230 fs/sync.c:188
         generic_write_sync include/linux/fs.h:2794 [inline]
         btrfs_do_write_iter+0x584/0x10c0 fs/btrfs/file.c:1705
         new_sync_write fs/read_write.c:497 [inline]
         vfs_write+0x6b6/0x1140 fs/read_write.c:590
         ksys_write+0x12f/0x260 fs/read_write.c:643
         do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
         __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
         do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
         entry_SYSENTER_compat_after_hwframe+0x84/0x8e

  -> #2 (btrfs_trans_num_extwriters){++++}-{0:0}:
         join_transaction+0x164/0xf40 fs/btrfs/transaction.c:315
         start_transaction+0x427/0x1a70 fs/btrfs/transaction.c:700
         btrfs_commit_super+0xa1/0x110 fs/btrfs/disk-io.c:4170
         close_ctree+0xcb0/0xf90 fs/btrfs/disk-io.c:4324
         generic_shutdown_super+0x159/0x3d0 fs/super.c:642
         kill_anon_super+0x3a/0x60 fs/super.c:1226
         btrfs_kill_super+0x3b/0x50 fs/btrfs/super.c:2096
         deactivate_locked_super+0xbe/0x1a0 fs/super.c:473
         deactivate_super+0xde/0x100 fs/super.c:506
         cleanup_mnt+0x222/0x450 fs/namespace.c:1267
         task_work_run+0x14e/0x250 kernel/task_work.c:180
         resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
         exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
         exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
         __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
         syscall_exit_to_user_mode+0x278/0x2a0 kernel/entry/common.c:218
         __do_fast_syscall_32+0x80/0x120 arch/x86/entry/common.c:389
         do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
         entry_SYSENTER_compat_after_hwframe+0x84/0x8e

  -> #1 (btrfs_trans_num_writers){++++}-{0:0}:
         __lock_release kernel/locking/lockdep.c:5468 [inline]
         lock_release+0x33e/0x6c0 kernel/locking/lockdep.c:5774
         percpu_up_read include/linux/percpu-rwsem.h:99 [inline]
         __sb_end_write include/linux/fs.h:1650 [inline]
         sb_end_intwrite include/linux/fs.h:1767 [inline]
         __btrfs_end_transaction+0x5ca/0x920 fs/btrfs/transaction.c:1071
         btrfs_commit_inode_delayed_inode+0x228/0x330 fs/btrfs/delayed-inode.c:1301
         btrfs_evict_inode+0x960/0xe80 fs/btrfs/inode.c:5291
         evict+0x2ed/0x6c0 fs/inode.c:667
         iput_final fs/inode.c:1741 [inline]
         iput.part.0+0x5a8/0x7f0 fs/inode.c:1767
         iput+0x5c/0x80 fs/inode.c:1757
         dentry_unlink_inode+0x295/0x480 fs/dcache.c:400
         __dentry_kill+0x1d0/0x600 fs/dcache.c:603
         dput.part.0+0x4b1/0x9b0 fs/dcache.c:845
         dput+0x1f/0x30 fs/dcache.c:835
         ovl_stack_put+0x60/0x90 fs/overlayfs/util.c:132
         ovl_destroy_inode+0xc6/0x190 fs/overlayfs/super.c:182
         destroy_inode+0xc4/0x1b0 fs/inode.c:311
         iput_final fs/inode.c:1741 [inline]
         iput.part.0+0x5a8/0x7f0 fs/inode.c:1767
         iput+0x5c/0x80 fs/inode.c:1757
         dentry_unlink_inode+0x295/0x480 fs/dcache.c:400
         __dentry_kill+0x1d0/0x600 fs/dcache.c:603
         shrink_kill fs/dcache.c:1048 [inline]
         shrink_dentry_list+0x140/0x5d0 fs/dcache.c:1075
         prune_dcache_sb+0xeb/0x150 fs/dcache.c:1156
         super_cache_scan+0x32a/0x550 fs/super.c:221
         do_shrink_slab+0x44f/0x11c0 mm/shrinker.c:435
         shrink_slab_memcg mm/shrinker.c:548 [inline]
         shrink_slab+0xa87/0x1310 mm/shrinker.c:626
         shrink_one+0x493/0x7c0 mm/vmscan.c:4790
         shrink_many mm/vmscan.c:4851 [inline]
         lru_gen_shrink_node+0x89f/0x1750 mm/vmscan.c:4951
         shrink_node mm/vmscan.c:5910 [inline]
         kswapd_shrink_node mm/vmscan.c:6720 [inline]
         balance_pgdat+0x1105/0x1970 mm/vmscan.c:6911
         kswapd+0x5ea/0xbf0 mm/vmscan.c:7180
         kthread+0x2c1/0x3a0 kernel/kthread.c:389
         ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
         ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

  -> #0 (fs_reclaim){+.+.}-{0:0}:
         check_prev_add kernel/locking/lockdep.c:3134 [inline]
         check_prevs_add kernel/locking/lockdep.c:3253 [inline]
         validate_chain kernel/locking/lockdep.c:3869 [inline]
         __lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137
         lock_acquire kernel/locking/lockdep.c:5754 [inline]
         lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719
         __fs_reclaim_acquire mm/page_alloc.c:3801 [inline]
         fs_reclaim_acquire+0x102/0x160 mm/page_alloc.c:3815
         might_alloc include/linux/sched/mm.h:334 [inline]
         slab_pre_alloc_hook mm/slub.c:3891 [inline]
         slab_alloc_node mm/slub.c:3981 [inline]
         kmem_cache_alloc_lru_noprof+0x58/0x2f0 mm/slub.c:4020
         btrfs_alloc_inode+0x118/0xb20 fs/btrfs/inode.c:8411
         alloc_inode+0x5d/0x230 fs/inode.c:261
         iget5_locked fs/inode.c:1235 [inline]
         iget5_locked+0x1c9/0x2c0 fs/inode.c:1228
         btrfs_iget_locked fs/btrfs/inode.c:5590 [inline]
         btrfs_iget_path fs/btrfs/inode.c:5607 [inline]
         btrfs_iget+0xfb/0x230 fs/btrfs/inode.c:5636
         add_conflicting_inode fs/btrfs/tree-log.c:5657 [inline]
         copy_inode_items_to_log+0x1039/0x1e30 fs/btrfs/tree-log.c:5928
         btrfs_log_inode+0xa48/0x4660 fs/btrfs/tree-log.c:6592
         log_new_delayed_dentries fs/btrfs/tree-log.c:6363 [inline]
         btrfs_log_inode+0x27dd/0x4660 fs/btrfs/tree-log.c:6718
         btrfs_log_all_parents fs/btrfs/tree-log.c:6833 [inline]
         btrfs_log_inode_parent+0x22ba/0x2a90 fs/btrfs/tree-log.c:7141
         btrfs_log_dentry_safe+0x59/0x80 fs/btrfs/tree-log.c:7180
         btrfs_sync_file+0x9c1/0xe10 fs/btrfs/file.c:1959
         vfs_fsync_range+0x141/0x230 fs/sync.c:188
         generic_write_sync include/linux/fs.h:2794 [inline]
         btrfs_do_write_iter+0x584/0x10c0 fs/btrfs/file.c:1705
         do_iter_readv_writev+0x504/0x780 fs/read_write.c:741
         vfs_writev+0x36f/0xde0 fs/read_write.c:971
         do_pwritev+0x1b2/0x260 fs/read_write.c:1072
         __do_compat_sys_pwritev2 fs/read_write.c:1218 [inline]
         __se_compat_sys_pwritev2 fs/read_write.c:1210 [inline]
         __ia32_compat_sys_pwritev2+0x121/0x1b0 fs/read_write.c:1210
         do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
         __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
         do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
         entry_SYSENTER_compat_after_hwframe+0x84/0x8e

  other info that might help us debug this:

  Chain exists of:
    fs_reclaim --> btrfs_trans_num_extwriters --> &ei->log_mutex

   Possible unsafe locking scenario:

         CPU0                    CPU1
         ----                    ----
    lock(&ei->log_mutex);
                                 lock(btrfs_trans_num_extwriters);
                                 lock(&ei->log_mutex);
    lock(fs_reclaim);

   *** DEADLOCK ***

  7 locks held by syz-executor.1/9919:
   #0: ffff88802be20420 (sb_writers#23){.+.+}-{0:0}, at: do_pwritev+0x1b2/0x260 fs/read_write.c:1072
   #1: ffff888065c0f8f0 (&sb->s_type->i_mutex_key#33){++++}-{3:3}, at: inode_lock include/linux/fs.h:791 [inline]
   #1: ffff888065c0f8f0 (&sb->s_type->i_mutex_key#33){++++}-{3:3}, at: btrfs_inode_lock+0xc8/0x110 fs/btrfs/inode.c:385
   #2: ffff888065c0f778 (&ei->i_mmap_lock){++++}-{3:3}, at: btrfs_inode_lock+0xee/0x110 fs/btrfs/inode.c:388
   #3: ffff88802be20610 (sb_internal#4){.+.+}-{0:0}, at: btrfs_sync_file+0x95b/0xe10 fs/btrfs/file.c:1952
   #4: ffff8880546323f0 (btrfs_trans_num_writers){++++}-{0:0}, at: join_transaction+0x430/0xf40 fs/btrfs/transaction.c:290
   #5: ffff888054632418 (btrfs_trans_num_extwriters){++++}-{0:0}, at: join_transaction+0x430/0xf40 fs/btrfs/transaction.c:290
   #6: ffff88804b569358 (&ei->log_mutex){+.+.}-{3:3}, at: btrfs_log_inode+0x39c/0x4660 fs/btrfs/tree-log.c:6481

  stack backtrace:
  CPU: 2 PID: 9919 Comm: syz-executor.1 Not tainted 6.10.0-rc2-syzkaller-00361-g061d1af7b030 #0
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
  Call Trace:
   <TASK>
   __dump_stack lib/dump_stack.c:88 [inline]
   dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
   check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2187
   check_prev_add kernel/locking/lockdep.c:3134 [inline]
   check_prevs_add kernel/locking/lockdep.c:3253 [inline]
   validate_chain kernel/locking/lockdep.c:3869 [inline]
   __lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137
   lock_acquire kernel/locking/lockdep.c:5754 [inline]
   lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719
   __fs_reclaim_acquire mm/page_alloc.c:3801 [inline]
   fs_reclaim_acquire+0x102/0x160 mm/page_alloc.c:3815
   might_alloc include/linux/sched/mm.h:334 [inline]
   slab_pre_alloc_hook mm/slub.c:3891 [inline]
   slab_alloc_node mm/slub.c:3981 [inline]
   kmem_cache_alloc_lru_noprof+0x58/0x2f0 mm/slub.c:4020
   btrfs_alloc_inode+0x118/0xb20 fs/btrfs/inode.c:8411
   alloc_inode+0x5d/0x230 fs/inode.c:261
   iget5_locked fs/inode.c:1235 [inline]
   iget5_locked+0x1c9/0x2c0 fs/inode.c:1228
   btrfs_iget_locked fs/btrfs/inode.c:5590 [inline]
   btrfs_iget_path fs/btrfs/inode.c:5607 [inline]
   btrfs_iget+0xfb/0x230 fs/btrfs/inode.c:5636
   add_conflicting_inode fs/btrfs/tree-log.c:5657 [inline]
   copy_inode_items_to_log+0x1039/0x1e30 fs/btrfs/tree-log.c:5928
   btrfs_log_inode+0xa48/0x4660 fs/btrfs/tree-log.c:6592
   log_new_delayed_dentries fs/btrfs/tree-log.c:6363 [inline]
   btrfs_log_inode+0x27dd/0x4660 fs/btrfs/tree-log.c:6718
   btrfs_log_all_parents fs/btrfs/tree-log.c:6833 [inline]
   btrfs_log_inode_parent+0x22ba/0x2a90 fs/btrfs/tree-log.c:7141
   btrfs_log_dentry_safe+0x59/0x80 fs/btrfs/tree-log.c:7180
   btrfs_sync_file+0x9c1/0xe10 fs/btrfs/file.c:1959
   vfs_fsync_range+0x141/0x230 fs/sync.c:188
   generic_write_sync include/linux/fs.h:2794 [inline]
   btrfs_do_write_iter+0x584/0x10c0 fs/btrfs/file.c:1705
   do_iter_readv_writev+0x504/0x780 fs/read_write.c:741
   vfs_writev+0x36f/0xde0 fs/read_write.c:971
   do_pwritev+0x1b2/0x260 fs/read_write.c:1072
   __do_compat_sys_pwritev2 fs/read_write.c:1218 [inline]
   __se_compat_sys_pwritev2 fs/read_write.c:1210 [inline]
   __ia32_compat_sys_pwritev2+0x121/0x1b0 fs/read_write.c:1210
   do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
   __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
   do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
   entry_SYSENTER_compat_after_hwframe+0x84/0x8e
  RIP: 0023:0xf7334579
  Code: b8 01 10 06 03 (...)
  RSP: 002b:00000000f5f265ac EFLAGS: 00000292 ORIG_RAX: 000000000000017b
  RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00000000200002c0
  RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000000
  RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
  R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000
  R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Fix this by ensuring we are under a NOFS scope whenever we call
btrfs_iget() during inode logging and log replay.

Reported-by: syzbot+8576cfa84070dce4d59b@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-btrfs/000000000000274a3a061abbd928@google.com/
Fixes: 712e36c ("btrfs: use GFP_KERNEL in btrfs_alloc_inode")
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
amboar pushed a commit that referenced this pull request Jul 10, 2024
commit be346c1 upstream.

The code in ocfs2_dio_end_io_write() estimates number of necessary
transaction credits using ocfs2_calc_extend_credits().  This however does
not take into account that the IO could be arbitrarily large and can
contain arbitrary number of extents.

Extent tree manipulations do often extend the current transaction but not
in all of the cases.  For example if we have only single block extents in
the tree, ocfs2_mark_extent_written() will end up calling
ocfs2_replace_extent_rec() all the time and we will never extend the
current transaction and eventually exhaust all the transaction credits if
the IO contains many single block extents.  Once that happens a
WARN_ON(jbd2_handle_buffer_credits(handle) <= 0) is triggered in
jbd2_journal_dirty_metadata() and subsequently OCFS2 aborts in response to
this error.  This was actually triggered by one of our customers on a
heavily fragmented OCFS2 filesystem.

To fix the issue make sure the transaction always has enough credits for
one extent insert before each call of ocfs2_mark_extent_written().

Heming Zhao said:

------
PANIC: "Kernel panic - not syncing: OCFS2: (device dm-1): panic forced after error"

PID: xxx  TASK: xxxx  CPU: 5  COMMAND: "SubmitThread-CA"
  #0 machine_kexec at ffffffff8c069932
  #1 __crash_kexec at ffffffff8c1338fa
  #2 panic at ffffffff8c1d69b9
  #3 ocfs2_handle_error at ffffffffc0c86c0c [ocfs2]
  #4 __ocfs2_abort at ffffffffc0c88387 [ocfs2]
  #5 ocfs2_journal_dirty at ffffffffc0c51e98 [ocfs2]
  #6 ocfs2_split_extent at ffffffffc0c27ea3 [ocfs2]
  #7 ocfs2_change_extent_flag at ffffffffc0c28053 [ocfs2]
  #8 ocfs2_mark_extent_written at ffffffffc0c28347 [ocfs2]
  #9 ocfs2_dio_end_io_write at ffffffffc0c2bef9 [ocfs2]
#10 ocfs2_dio_end_io at ffffffffc0c2c0f5 [ocfs2]
#11 dio_complete at ffffffff8c2b9fa7
#12 do_blockdev_direct_IO at ffffffff8c2bc09f
#13 ocfs2_direct_IO at ffffffffc0c2b653 [ocfs2]
#14 generic_file_direct_write at ffffffff8c1dcf14
#15 __generic_file_write_iter at ffffffff8c1dd07b
#16 ocfs2_file_write_iter at ffffffffc0c49f1f [ocfs2]
#17 aio_write at ffffffff8c2cc72e
#18 kmem_cache_alloc at ffffffff8c248dde
#19 do_io_submit at ffffffff8c2ccada
#20 do_syscall_64 at ffffffff8c004984
#21 entry_SYSCALL_64_after_hwframe at ffffffff8c8000ba

Link: https://lkml.kernel.org/r/20240617095543.6971-1-jack@suse.cz
Link: https://lkml.kernel.org/r/20240614145243.8837-1-jack@suse.cz
Fixes: c15471f ("ocfs2: fix sparse file & data ordering issue in direct io")
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Reviewed-by: Heming Zhao <heming.zhao@suse.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amboar pushed a commit that referenced this pull request Jul 26, 2024
commit f1a8f40 upstream.

This fixes the following deadlock introduced by 39a92a5
("bluetooth/l2cap: sync sock recv cb and release")

============================================
WARNING: possible recursive locking detected
6.10.0-rc3-g4029dba6b6f1 #6823 Not tainted
--------------------------------------------
kworker/u5:0/35 is trying to acquire lock:
ffff888002ec2510 (&chan->lock#2/1){+.+.}-{3:3}, at:
l2cap_sock_recv_cb+0x44/0x1e0

but task is already holding lock:
ffff888002ec2510 (&chan->lock#2/1){+.+.}-{3:3}, at:
l2cap_get_chan_by_scid+0xaf/0xd0

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

       CPU0
       ----
  lock(&chan->lock#2/1);
  lock(&chan->lock#2/1);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

3 locks held by kworker/u5:0/35:
 #0: ffff888002b8a940 ((wq_completion)hci0#2){+.+.}-{0:0}, at:
process_one_work+0x750/0x930
 #1: ffff888002c67dd0 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0},
at: process_one_work+0x44e/0x930
 #2: ffff888002ec2510 (&chan->lock#2/1){+.+.}-{3:3}, at:
l2cap_get_chan_by_scid+0xaf/0xd0

To fix the original problem this introduces l2cap_chan_lock at
l2cap_conless_channel to ensure that l2cap_sock_recv_cb is called with
chan->lock held.

Fixes: 89e856e ("bluetooth/l2cap: sync sock recv cb and release")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amboar pushed a commit that referenced this pull request Aug 5, 2024
commit 667574e upstream.

When tries to demote 1G hugetlb folios, a lockdep warning is observed:

============================================
WARNING: possible recursive locking detected
6.10.0-rc6-00452-ga4d0275fa660-dirty #79 Not tainted
--------------------------------------------
bash/710 is trying to acquire lock:
ffffffff8f0a7850 (&h->resize_lock){+.+.}-{3:3}, at: demote_store+0x244/0x460

but task is already holding lock:
ffffffff8f0a6f48 (&h->resize_lock){+.+.}-{3:3}, at: demote_store+0xae/0x460

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

       CPU0
       ----
  lock(&h->resize_lock);
  lock(&h->resize_lock);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

4 locks held by bash/710:
 #0: ffff8f118439c3f0 (sb_writers#5){.+.+}-{0:0}, at: ksys_write+0x64/0xe0
 #1: ffff8f11893b9e88 (&of->mutex#2){+.+.}-{3:3}, at: kernfs_fop_write_iter+0xf8/0x1d0
 #2: ffff8f1183dc4428 (kn->active#98){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x100/0x1d0
 #3: ffffffff8f0a6f48 (&h->resize_lock){+.+.}-{3:3}, at: demote_store+0xae/0x460

stack backtrace:
CPU: 3 PID: 710 Comm: bash Not tainted 6.10.0-rc6-00452-ga4d0275fa660-dirty #79
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x68/0xa0
 __lock_acquire+0x10f2/0x1ca0
 lock_acquire+0xbe/0x2d0
 __mutex_lock+0x6d/0x400
 demote_store+0x244/0x460
 kernfs_fop_write_iter+0x12c/0x1d0
 vfs_write+0x380/0x540
 ksys_write+0x64/0xe0
 do_syscall_64+0xb9/0x1d0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa61db14887
RSP: 002b:00007ffc56c48358 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007fa61db14887
RDX: 0000000000000002 RSI: 000055a030050220 RDI: 0000000000000001
RBP: 000055a030050220 R08: 00007fa61dbd1460 R09: 000000007fffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002
R13: 00007fa61dc1b780 R14: 00007fa61dc17600 R15: 00007fa61dc16a00
 </TASK>

Lockdep considers this an AA deadlock because the different resize_lock
mutexes reside in the same lockdep class, but this is a false positive.
Place them in distinct classes to avoid these warnings.

Link: https://lkml.kernel.org/r/20240712031314.2570452-1-linmiaohe@huawei.com
Fixes: 8531fc6 ("hugetlb: add hugetlb demote page support")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Muchun Song <muchun.song@linux.dev>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amboar pushed a commit that referenced this pull request Aug 5, 2024
commit 9798192 upstream.

Current ata_gen_passthru_sense() code performs two actions:
1. Generates sense data based on the ATA 'status' and ATA 'error' fields.
2. Populates "ATA Status Return sense data descriptor" / "Fixed format
   sense data" with ATA taskfile fields.

The problem is that #1 generates sense data even when a valid sense data
is already present (ATA_QCFLAG_SENSE_VALID is set). Factoring out #2 into
a separate function allows us to generate sense data only when there is
no valid sense data (ATA_QCFLAG_SENSE_VALID is not set).

As a bonus, we can now delete a FIXME comment in atapi_qc_complete()
which states that we don't want to translate taskfile registers into
sense descriptors for ATAPI.

Additionally, always set SAM_STAT_CHECK_CONDITION when CK_COND=1 because
SAT specification mandates that SATL shall return CHECK CONDITION if
the CK_COND bit is set.

The ATA PASS-THROUGH handling logic in ata_scsi_qc_complete() is hard
to read/understand. Improve the readability of the code by moving checks
into self-explanatory boolean variables.

Cc: stable@vger.kernel.org # 4.19+
Co-developed-by: Niklas Cassel <cassel@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Niklas Cassel <cassel@kernel.org>
Signed-off-by: Igor Pylypiv <ipylypiv@google.com>
Link: https://lore.kernel.org/r/20240702024735.1152293-3-ipylypiv@google.com
Signed-off-by: Niklas Cassel <cassel@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amboar pushed a commit that referenced this pull request Aug 15, 2024
[ Upstream commit 3e7917c ]

linkwatch_event() grabs possibly very contended RTNL mutex.

system_wq is not suitable for such work.

Inspired by many noisy syzbot reports.

3 locks held by kworker/0:7/5266:
 #0: ffff888015480948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline]
 #0: ffff888015480948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312
 #1: ffffc90003f6fd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline]
 , at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312
 #2: ffffffff8fa6f208 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276

Reported-by: syzbot <syzkaller@googlegroups.com>
Fixes: 1da177e ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20240805085821.1616528-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
amboar pushed a commit that referenced this pull request Aug 15, 2024
[ Upstream commit 86a41ea ]

When l2tp tunnels use a socket provided by userspace, we can hit
lockdep splats like the below when data is transmitted through another
(unrelated) userspace socket which then gets routed over l2tp.

This issue was previously discussed here:
https://lore.kernel.org/netdev/87sfialu2n.fsf@cloudflare.com/

The solution is to have lockdep treat socket locks of l2tp tunnel
sockets separately than those of standard INET sockets. To do so, use
a different lockdep subclass where lock nesting is possible.

  ============================================
  WARNING: possible recursive locking detected
  6.10.0+ #34 Not tainted
  --------------------------------------------
  iperf3/771 is trying to acquire lock:
  ffff8881027601d8 (slock-AF_INET/1){+.-.}-{2:2}, at: l2tp_xmit_skb+0x243/0x9d0

  but task is already holding lock:
  ffff888102650d98 (slock-AF_INET/1){+.-.}-{2:2}, at: tcp_v4_rcv+0x1848/0x1e10

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

         CPU0
         ----
    lock(slock-AF_INET/1);
    lock(slock-AF_INET/1);

   *** DEADLOCK ***

   May be due to missing lock nesting notation

  10 locks held by iperf3/771:
   #0: ffff888102650258 (sk_lock-AF_INET){+.+.}-{0:0}, at: tcp_sendmsg+0x1a/0x40
   #1: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: __ip_queue_xmit+0x4b/0xbc0
   #2: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: ip_finish_output2+0x17a/0x1130
   #3: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: process_backlog+0x28b/0x9f0
   #4: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: ip_local_deliver_finish+0xf9/0x260
   #5: ffff888102650d98 (slock-AF_INET/1){+.-.}-{2:2}, at: tcp_v4_rcv+0x1848/0x1e10
   #6: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: __ip_queue_xmit+0x4b/0xbc0
   #7: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: ip_finish_output2+0x17a/0x1130
   #8: ffffffff822ac1e0 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0xcc/0x1450
   #9: ffff888101f33258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock#2){+...}-{2:2}, at: __dev_queue_xmit+0x513/0x1450

  stack backtrace:
  CPU: 2 UID: 0 PID: 771 Comm: iperf3 Not tainted 6.10.0+ #34
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
  Call Trace:
   <IRQ>
   dump_stack_lvl+0x69/0xa0
   dump_stack+0xc/0x20
   __lock_acquire+0x135d/0x2600
   ? srso_alias_return_thunk+0x5/0xfbef5
   lock_acquire+0xc4/0x2a0
   ? l2tp_xmit_skb+0x243/0x9d0
   ? __skb_checksum+0xa3/0x540
   _raw_spin_lock_nested+0x35/0x50
   ? l2tp_xmit_skb+0x243/0x9d0
   l2tp_xmit_skb+0x243/0x9d0
   l2tp_eth_dev_xmit+0x3c/0xc0
   dev_hard_start_xmit+0x11e/0x420
   sch_direct_xmit+0xc3/0x640
   __dev_queue_xmit+0x61c/0x1450
   ? ip_finish_output2+0xf4c/0x1130
   ip_finish_output2+0x6b6/0x1130
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __ip_finish_output+0x217/0x380
   ? srso_alias_return_thunk+0x5/0xfbef5
   __ip_finish_output+0x217/0x380
   ip_output+0x99/0x120
   __ip_queue_xmit+0xae4/0xbc0
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? tcp_options_write.constprop.0+0xcb/0x3e0
   ip_queue_xmit+0x34/0x40
   __tcp_transmit_skb+0x1625/0x1890
   __tcp_send_ack+0x1b8/0x340
   tcp_send_ack+0x23/0x30
   __tcp_ack_snd_check+0xa8/0x530
   ? srso_alias_return_thunk+0x5/0xfbef5
   tcp_rcv_established+0x412/0xd70
   tcp_v4_do_rcv+0x299/0x420
   tcp_v4_rcv+0x1991/0x1e10
   ip_protocol_deliver_rcu+0x50/0x220
   ip_local_deliver_finish+0x158/0x260
   ip_local_deliver+0xc8/0xe0
   ip_rcv+0xe5/0x1d0
   ? __pfx_ip_rcv+0x10/0x10
   __netif_receive_skb_one_core+0xce/0xe0
   ? process_backlog+0x28b/0x9f0
   __netif_receive_skb+0x34/0xd0
   ? process_backlog+0x28b/0x9f0
   process_backlog+0x2cb/0x9f0
   __napi_poll.constprop.0+0x61/0x280
   net_rx_action+0x332/0x670
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? find_held_lock+0x2b/0x80
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   handle_softirqs+0xda/0x480
   ? __dev_queue_xmit+0xa2c/0x1450
   do_softirq+0xa1/0xd0
   </IRQ>
   <TASK>
   __local_bh_enable_ip+0xc8/0xe0
   ? __dev_queue_xmit+0xa2c/0x1450
   __dev_queue_xmit+0xa48/0x1450
   ? ip_finish_output2+0xf4c/0x1130
   ip_finish_output2+0x6b6/0x1130
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __ip_finish_output+0x217/0x380
   ? srso_alias_return_thunk+0x5/0xfbef5
   __ip_finish_output+0x217/0x380
   ip_output+0x99/0x120
   __ip_queue_xmit+0xae4/0xbc0
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? tcp_options_write.constprop.0+0xcb/0x3e0
   ip_queue_xmit+0x34/0x40
   __tcp_transmit_skb+0x1625/0x1890
   tcp_write_xmit+0x766/0x2fb0
   ? __entry_text_end+0x102ba9/0x102bad
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __might_fault+0x74/0xc0
   ? srso_alias_return_thunk+0x5/0xfbef5
   __tcp_push_pending_frames+0x56/0x190
   tcp_push+0x117/0x310
   tcp_sendmsg_locked+0x14c1/0x1740
   tcp_sendmsg+0x28/0x40
   inet_sendmsg+0x5d/0x90
   sock_write_iter+0x242/0x2b0
   vfs_write+0x68d/0x800
   ? __pfx_sock_write_iter+0x10/0x10
   ksys_write+0xc8/0xf0
   __x64_sys_write+0x3d/0x50
   x64_sys_call+0xfaf/0x1f50
   do_syscall_64+0x6d/0x140
   entry_SYSCALL_64_after_hwframe+0x76/0x7e
  RIP: 0033:0x7f4d143af992
  Code: c3 8b 07 85 c0 75 24 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 <c3> e9 01 cc ff ff 41 54 b8 02 00 00 0
  RSP: 002b:00007ffd65032058 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
  RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f4d143af992
  RDX: 0000000000000025 RSI: 00007f4d143f3bcc RDI: 0000000000000005
  RBP: 00007f4d143f2b28 R08: 0000000000000000 R09: 0000000000000000
  R10: 0000000000000000 R11: 0000000000000246 R12: 00007f4d143f3bcc
  R13: 0000000000000005 R14: 0000000000000000 R15: 00007ffd650323f0
   </TASK>

Fixes: 0b2c597 ("l2tp: close all race conditions in l2tp_tunnel_register()")
Suggested-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot+6acef9e0a4d1f46c83d4@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=6acef9e0a4d1f46c83d4
CC: gnault@redhat.com
CC: cong.wang@bytedance.com
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Link: https://patch.msgid.link/20240806160626.1248317-1-jchapman@katalix.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
amboar pushed a commit that referenced this pull request Aug 15, 2024
…pinlock_t'

commit f872d4a upstream.

This lock is acquired under irq_desc::lock with interrupts disabled.

When PREEMPT_RT is enabled, 'spinlock_t' becomes preemptible, which results
in invalid lock acquire context;

  [ BUG: Invalid wait context ]
  swapper/0/1 is trying to lock:
  ffff0000008fed30 (&ctl->lock){....}-{3:3}, at: meson_gpio_irq_update_bits0
  other info that might help us debug this:
  context-{5:5}
  3 locks held by swapper/0/1:
   #0: ffff0000003cd0f8 (&dev->mutex){....}-{4:4}, at: __driver_attach+0x90c
   #1: ffff000004714650 (&desc->request_mutex){+.+.}-{4:4}, at: __setup_irq0
   #2: ffff0000047144c8 (&irq_desc_lock_class){-.-.}-{2:2}, at: __setup_irq0
  stack backtrace:
  CPU: 1 PID: 1 Comm: swapper/0 Not tainted 6.9.9-sdkernel #1
  Call trace:
   _raw_spin_lock_irqsave+0x60/0x88
   meson_gpio_irq_update_bits+0x34/0x70
   meson8_gpio_irq_set_type+0x78/0xc4
   meson_gpio_irq_set_type+0x30/0x60
   __irq_set_trigger+0x60/0x180
   __setup_irq+0x30c/0x6e0
   request_threaded_irq+0xec/0x1a4

Fixes: 215f4cc ("irqchip/meson: Add support for gpio interrupt controller")
Signed-off-by: Arseniy Krasnov <avkrasnov@salutedevices.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/all/20240729131850.3015508-1-avkrasnov@salutedevices.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
dkodihal pushed a commit to NVIDIA/linux that referenced this pull request Aug 21, 2024
[ Upstream commit 169410e ]

These three bpf_map_{lookup,update,delete}_elem() helpers are also
available for sleepable bpf program, so add the corresponding lock
assertion for sleepable bpf program, otherwise the following warning
will be reported when a sleepable bpf program manipulates bpf map under
interpreter mode (aka bpf_jit_enable=0):

  WARNING: CPU: 3 PID: 4985 at kernel/bpf/helpers.c:40 ......
  CPU: 3 PID: 4985 Comm: test_progs Not tainted 6.6.0+ openbmc#2
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) ......
  RIP: 0010:bpf_map_lookup_elem+0x54/0x60
  ......
  Call Trace:
   <TASK>
   ? __warn+0xa5/0x240
   ? bpf_map_lookup_elem+0x54/0x60
   ? report_bug+0x1ba/0x1f0
   ? handle_bug+0x40/0x80
   ? exc_invalid_op+0x18/0x50
   ? asm_exc_invalid_op+0x1b/0x20
   ? __pfx_bpf_map_lookup_elem+0x10/0x10
   ? rcu_lockdep_current_cpu_online+0x65/0xb0
   ? rcu_is_watching+0x23/0x50
   ? bpf_map_lookup_elem+0x54/0x60
   ? __pfx_bpf_map_lookup_elem+0x10/0x10
   ___bpf_prog_run+0x513/0x3b70
   __bpf_prog_run32+0x9d/0xd0
   ? __bpf_prog_enter_sleepable_recur+0xad/0x120
   ? __bpf_prog_enter_sleepable_recur+0x3e/0x120
   bpf_trampoline_6442580665+0x4d/0x1000
   __x64_sys_getpgid+0x5/0x30
   ? do_syscall_64+0x36/0xb0
   entry_SYSCALL_64_after_hwframe+0x6e/0x76
   </TASK>

Signed-off-by: Hou Tao <houtao1@huawei.com>
Link: https://lore.kernel.org/r/20231204140425.1480317-2-houtao@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
amboar pushed a commit that referenced this pull request Aug 30, 2024
[ Upstream commit b313a8c ]

Lockdep reported a warning in Linux version 6.6:

[  414.344659] ================================
[  414.345155] WARNING: inconsistent lock state
[  414.345658] 6.6.0-07439-gba2303cacfda #6 Not tainted
[  414.346221] --------------------------------
[  414.346712] inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage.
[  414.347545] kworker/u10:3/1152 [HC0[0]:SC0[0]:HE0:SE1] takes:
[  414.349245] ffff88810edd1098 (&sbq->ws[i].wait){+.?.}-{2:2}, at: blk_mq_dispatch_rq_list+0x131c/0x1ee0
[  414.351204] {IN-SOFTIRQ-W} state was registered at:
[  414.351751]   lock_acquire+0x18d/0x460
[  414.352218]   _raw_spin_lock_irqsave+0x39/0x60
[  414.352769]   __wake_up_common_lock+0x22/0x60
[  414.353289]   sbitmap_queue_wake_up+0x375/0x4f0
[  414.353829]   sbitmap_queue_clear+0xdd/0x270
[  414.354338]   blk_mq_put_tag+0xdf/0x170
[  414.354807]   __blk_mq_free_request+0x381/0x4d0
[  414.355335]   blk_mq_free_request+0x28b/0x3e0
[  414.355847]   __blk_mq_end_request+0x242/0xc30
[  414.356367]   scsi_end_request+0x2c1/0x830
[  414.345155] WARNING: inconsistent lock state
[  414.345658] 6.6.0-07439-gba2303cacfda #6 Not tainted
[  414.346221] --------------------------------
[  414.346712] inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage.
[  414.347545] kworker/u10:3/1152 [HC0[0]:SC0[0]:HE0:SE1] takes:
[  414.349245] ffff88810edd1098 (&sbq->ws[i].wait){+.?.}-{2:2}, at: blk_mq_dispatch_rq_list+0x131c/0x1ee0
[  414.351204] {IN-SOFTIRQ-W} state was registered at:
[  414.351751]   lock_acquire+0x18d/0x460
[  414.352218]   _raw_spin_lock_irqsave+0x39/0x60
[  414.352769]   __wake_up_common_lock+0x22/0x60
[  414.353289]   sbitmap_queue_wake_up+0x375/0x4f0
[  414.353829]   sbitmap_queue_clear+0xdd/0x270
[  414.354338]   blk_mq_put_tag+0xdf/0x170
[  414.354807]   __blk_mq_free_request+0x381/0x4d0
[  414.355335]   blk_mq_free_request+0x28b/0x3e0
[  414.355847]   __blk_mq_end_request+0x242/0xc30
[  414.356367]   scsi_end_request+0x2c1/0x830
[  414.356863]   scsi_io_completion+0x177/0x1610
[  414.357379]   scsi_complete+0x12f/0x260
[  414.357856]   blk_complete_reqs+0xba/0xf0
[  414.358338]   __do_softirq+0x1b0/0x7a2
[  414.358796]   irq_exit_rcu+0x14b/0x1a0
[  414.359262]   sysvec_call_function_single+0xaf/0xc0
[  414.359828]   asm_sysvec_call_function_single+0x1a/0x20
[  414.360426]   default_idle+0x1e/0x30
[  414.360873]   default_idle_call+0x9b/0x1f0
[  414.361390]   do_idle+0x2d2/0x3e0
[  414.361819]   cpu_startup_entry+0x55/0x60
[  414.362314]   start_secondary+0x235/0x2b0
[  414.362809]   secondary_startup_64_no_verify+0x18f/0x19b
[  414.363413] irq event stamp: 428794
[  414.363825] hardirqs last  enabled at (428793): [<ffffffff816bfd1c>] ktime_get+0x1dc/0x200
[  414.364694] hardirqs last disabled at (428794): [<ffffffff85470177>] _raw_spin_lock_irq+0x47/0x50
[  414.365629] softirqs last  enabled at (428444): [<ffffffff85474780>] __do_softirq+0x540/0x7a2
[  414.366522] softirqs last disabled at (428419): [<ffffffff813f65ab>] irq_exit_rcu+0x14b/0x1a0
[  414.367425]
               other info that might help us debug this:
[  414.368194]  Possible unsafe locking scenario:
[  414.368900]        CPU0
[  414.369225]        ----
[  414.369548]   lock(&sbq->ws[i].wait);
[  414.370000]   <Interrupt>
[  414.370342]     lock(&sbq->ws[i].wait);
[  414.370802]
                *** DEADLOCK ***
[  414.371569] 5 locks held by kworker/u10:3/1152:
[  414.372088]  #0: ffff88810130e938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x357/0x13f0
[  414.373180]  #1: ffff88810201fdb8 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x3a3/0x13f0
[  414.374384]  #2: ffffffff86ffbdc0 (rcu_read_lock){....}-{1:2}, at: blk_mq_run_hw_queue+0x637/0xa00
[  414.375342]  #3: ffff88810edd1098 (&sbq->ws[i].wait){+.?.}-{2:2}, at: blk_mq_dispatch_rq_list+0x131c/0x1ee0
[  414.376377]  #4: ffff888106205a08 (&hctx->dispatch_wait_lock){+.-.}-{2:2}, at: blk_mq_dispatch_rq_list+0x1337/0x1ee0
[  414.378607]
               stack backtrace:
[  414.379177] CPU: 0 PID: 1152 Comm: kworker/u10:3 Not tainted 6.6.0-07439-gba2303cacfda #6
[  414.380032] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
[  414.381177] Workqueue: writeback wb_workfn (flush-253:0)
[  414.381805] Call Trace:
[  414.382136]  <TASK>
[  414.382429]  dump_stack_lvl+0x91/0xf0
[  414.382884]  mark_lock_irq+0xb3b/0x1260
[  414.383367]  ? __pfx_mark_lock_irq+0x10/0x10
[  414.383889]  ? stack_trace_save+0x8e/0xc0
[  414.384373]  ? __pfx_stack_trace_save+0x10/0x10
[  414.384903]  ? graph_lock+0xcf/0x410
[  414.385350]  ? save_trace+0x3d/0xc70
[  414.385808]  mark_lock.part.20+0x56d/0xa90
[  414.386317]  mark_held_locks+0xb0/0x110
[  414.386791]  ? __pfx_do_raw_spin_lock+0x10/0x10
[  414.387320]  lockdep_hardirqs_on_prepare+0x297/0x3f0
[  414.387901]  ? _raw_spin_unlock_irq+0x28/0x50
[  414.388422]  trace_hardirqs_on+0x58/0x100
[  414.388917]  _raw_spin_unlock_irq+0x28/0x50
[  414.389422]  __blk_mq_tag_busy+0x1d6/0x2a0
[  414.389920]  __blk_mq_get_driver_tag+0x761/0x9f0
[  414.390899]  blk_mq_dispatch_rq_list+0x1780/0x1ee0
[  414.391473]  ? __pfx_blk_mq_dispatch_rq_list+0x10/0x10
[  414.392070]  ? sbitmap_get+0x2b8/0x450
[  414.392533]  ? __blk_mq_get_driver_tag+0x210/0x9f0
[  414.393095]  __blk_mq_sched_dispatch_requests+0xd99/0x1690
[  414.393730]  ? elv_attempt_insert_merge+0x1b1/0x420
[  414.394302]  ? __pfx___blk_mq_sched_dispatch_requests+0x10/0x10
[  414.394970]  ? lock_acquire+0x18d/0x460
[  414.395456]  ? blk_mq_run_hw_queue+0x637/0xa00
[  414.395986]  ? __pfx_lock_acquire+0x10/0x10
[  414.396499]  blk_mq_sched_dispatch_requests+0x109/0x190
[  414.397100]  blk_mq_run_hw_queue+0x66e/0xa00
[  414.397616]  blk_mq_flush_plug_list.part.17+0x614/0x2030
[  414.398244]  ? __pfx_blk_mq_flush_plug_list.part.17+0x10/0x10
[  414.398897]  ? writeback_sb_inodes+0x241/0xcc0
[  414.399429]  blk_mq_flush_plug_list+0x65/0x80
[  414.399957]  __blk_flush_plug+0x2f1/0x530
[  414.400458]  ? __pfx___blk_flush_plug+0x10/0x10
[  414.400999]  blk_finish_plug+0x59/0xa0
[  414.401467]  wb_writeback+0x7cc/0x920
[  414.401935]  ? __pfx_wb_writeback+0x10/0x10
[  414.402442]  ? mark_held_locks+0xb0/0x110
[  414.402931]  ? __pfx_do_raw_spin_lock+0x10/0x10
[  414.403462]  ? lockdep_hardirqs_on_prepare+0x297/0x3f0
[  414.404062]  wb_workfn+0x2b3/0xcf0
[  414.404500]  ? __pfx_wb_workfn+0x10/0x10
[  414.404989]  process_scheduled_works+0x432/0x13f0
[  414.405546]  ? __pfx_process_scheduled_works+0x10/0x10
[  414.406139]  ? do_raw_spin_lock+0x101/0x2a0
[  414.406641]  ? assign_work+0x19b/0x240
[  414.407106]  ? lock_is_held_type+0x9d/0x110
[  414.407604]  worker_thread+0x6f2/0x1160
[  414.408075]  ? __kthread_parkme+0x62/0x210
[  414.408572]  ? lockdep_hardirqs_on_prepare+0x297/0x3f0
[  414.409168]  ? __kthread_parkme+0x13c/0x210
[  414.409678]  ? __pfx_worker_thread+0x10/0x10
[  414.410191]  kthread+0x33c/0x440
[  414.410602]  ? __pfx_kthread+0x10/0x10
[  414.411068]  ret_from_fork+0x4d/0x80
[  414.411526]  ? __pfx_kthread+0x10/0x10
[  414.411993]  ret_from_fork_asm+0x1b/0x30
[  414.412489]  </TASK>

When interrupt is turned on while a lock holding by spin_lock_irq it
throws a warning because of potential deadlock.

blk_mq_prep_dispatch_rq
 blk_mq_get_driver_tag
  __blk_mq_get_driver_tag
   __blk_mq_alloc_driver_tag
    blk_mq_tag_busy -> tag is already busy
    // failed to get driver tag
 blk_mq_mark_tag_wait
  spin_lock_irq(&wq->lock) -> lock A (&sbq->ws[i].wait)
  __add_wait_queue(wq, wait) -> wait queue active
  blk_mq_get_driver_tag
  __blk_mq_tag_busy
-> 1) tag must be idle, which means there can't be inflight IO
   spin_lock_irq(&tags->lock) -> lock B (hctx->tags)
   spin_unlock_irq(&tags->lock) -> unlock B, turn on interrupt accidentally
-> 2) context must be preempt by IO interrupt to trigger deadlock.

As shown above, the deadlock is not possible in theory, but the warning
still need to be fixed.

Fix it by using spin_lock_irqsave to get lockB instead of spin_lock_irq.

Fixes: 4f1731d ("blk-mq: fix potential io hang by wrong 'wake_batch'")
Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20240815024736.2040971-1-lilingfeng@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
amboar pushed a commit that referenced this pull request Sep 10, 2024
[ Upstream commit bd44ca3 ]

Currently the dma debugging code can end up indirectly calling printk
under the radix_lock. This happens when a radix tree node allocation
fails.

This is a problem because the printk code, when used together with
netconsole, can end up inside the dma debugging code while trying to
transmit a message over netcons.

This creates the possibility of either a circular deadlock on the same
CPU, with that CPU trying to grab the radix_lock twice, or an ABBA
deadlock between different CPUs, where one CPU grabs the console lock
first and then waits for the radix_lock, while the other CPU is holding
the radix_lock and is waiting for the console lock.

The trace captured by lockdep is of the ABBA variant.

-> #2 (&dma_entry_hash[i].lock){-.-.}-{2:2}:
                  _raw_spin_lock_irqsave+0x5a/0x90
                  debug_dma_map_page+0x79/0x180
                  dma_map_page_attrs+0x1d2/0x2f0
                  bnxt_start_xmit+0x8c6/0x1540
                  netpoll_start_xmit+0x13f/0x180
                  netpoll_send_skb+0x20d/0x320
                  netpoll_send_udp+0x453/0x4a0
                  write_ext_msg+0x1b9/0x460
                  console_flush_all+0x2ff/0x5a0
                  console_unlock+0x55/0x180
                  vprintk_emit+0x2e3/0x3c0
                  devkmsg_emit+0x5a/0x80
                  devkmsg_write+0xfd/0x180
                  do_iter_readv_writev+0x164/0x1b0
                  vfs_writev+0xf9/0x2b0
                  do_writev+0x6d/0x110
                  do_syscall_64+0x80/0x150
                  entry_SYSCALL_64_after_hwframe+0x4b/0x53

-> #0 (console_owner){-.-.}-{0:0}:
                  __lock_acquire+0x15d1/0x31a0
                  lock_acquire+0xe8/0x290
                  console_flush_all+0x2ea/0x5a0
                  console_unlock+0x55/0x180
                  vprintk_emit+0x2e3/0x3c0
                  _printk+0x59/0x80
                  warn_alloc+0x122/0x1b0
                  __alloc_pages_slowpath+0x1101/0x1120
                  __alloc_pages+0x1eb/0x2c0
                  alloc_slab_page+0x5f/0x150
                  new_slab+0x2dc/0x4e0
                  ___slab_alloc+0xdcb/0x1390
                  kmem_cache_alloc+0x23d/0x360
                  radix_tree_node_alloc+0x3c/0xf0
                  radix_tree_insert+0xf5/0x230
                  add_dma_entry+0xe9/0x360
                  dma_map_page_attrs+0x1d2/0x2f0
                  __bnxt_alloc_rx_frag+0x147/0x180
                  bnxt_alloc_rx_data+0x79/0x160
                  bnxt_rx_skb+0x29/0xc0
                  bnxt_rx_pkt+0xe22/0x1570
                  __bnxt_poll_work+0x101/0x390
                  bnxt_poll+0x7e/0x320
                  __napi_poll+0x29/0x160
                  net_rx_action+0x1e0/0x3e0
                  handle_softirqs+0x190/0x510
                  run_ksoftirqd+0x4e/0x90
                  smpboot_thread_fn+0x1a8/0x270
                  kthread+0x102/0x120
                  ret_from_fork+0x2f/0x40
                  ret_from_fork_asm+0x11/0x20

This bug is more likely than it seems, because when one CPU has run out
of memory, chances are the other has too.

The good news is, this bug is hidden behind the CONFIG_DMA_API_DEBUG, so
not many users are likely to trigger it.

Signed-off-by: Rik van Riel <riel@surriel.com>
Reported-by: Konstantin Ovsepian <ovs@meta.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
amboar pushed a commit that referenced this pull request Sep 10, 2024
[ Upstream commit 56f4526 ]

This timer HW supports 8, 16 and 32-bit timer widths. This
driver currently uses a u32 to store the max possible value
of the timer. However, statements perform addition of 2 in
xilinx_pwm_apply() when calculating the period_cycles and
duty_cycles values. Since priv->max is a u32, this will
result in an overflow to 1 which will not only be incorrect
but fail on range comparison. This results in making it
impossible to set the PWM in this timer mode.

There are two obvious solutions to the current problem:
1. Cast each instance where overflow occurs to u64.
2. Change priv->max from a u32 to a u64.

Solution #1 requires more code modifications, and leaves
opportunity to introduce similar overflows if other math
statements are added in the future. These may also go
undetected if running in non 32-bit timer modes.

Solution #2 is the much smaller and cleaner approach and
thus the chosen method in this patch.

This was tested on a Zynq UltraScale+ with multiple
instances of the PWM IP.

Signed-off-by: Ken Sloat <ksloat@designlinxhs.com>
Reviewed-by: Michal Simek <michal.simek@amd.com>
Reviewed-by: Sean Anderson <sean.anderson@seco.com>
Link: https://lore.kernel.org/r/SJ0P222MB0107490C5371B848EF04351CA1E19@SJ0P222MB0107.NAMP222.PROD.OUTLOOK.COM
Signed-off-by: Michal Simek <michal.simek@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
amboar pushed a commit that referenced this pull request Sep 13, 2024
commit f9c169b upstream.

If smb2_compound_op() is called with a valid @CFILE and returned
-EINVAL, we need to call cifs_get_writable_path() before retrying it
as the reference of @CFILE was already dropped by previous call.

This fixes the following KASAN splat when running fstests generic/013
against Windows Server 2022:

  CIFS: Attempting to mount //w22-fs0/scratch
  run fstests generic/013 at 2024-09-02 19:48:59
  ==================================================================
  BUG: KASAN: slab-use-after-free in detach_if_pending+0xab/0x200
  Write of size 8 at addr ffff88811f1a3730 by task kworker/3:2/176

  CPU: 3 UID: 0 PID: 176 Comm: kworker/3:2 Not tainted 6.11.0-rc6 #2
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-2.fc40
  04/01/2014
  Workqueue: cifsoplockd cifs_oplock_break [cifs]
  Call Trace:
   <TASK>
   dump_stack_lvl+0x5d/0x80
   ? detach_if_pending+0xab/0x200
   print_report+0x156/0x4d9
   ? detach_if_pending+0xab/0x200
   ? __virt_addr_valid+0x145/0x300
   ? __phys_addr+0x46/0x90
   ? detach_if_pending+0xab/0x200
   kasan_report+0xda/0x110
   ? detach_if_pending+0xab/0x200
   detach_if_pending+0xab/0x200
   timer_delete+0x96/0xe0
   ? __pfx_timer_delete+0x10/0x10
   ? rcu_is_watching+0x20/0x50
   try_to_grab_pending+0x46/0x3b0
   __cancel_work+0x89/0x1b0
   ? __pfx___cancel_work+0x10/0x10
   ? kasan_save_track+0x14/0x30
   cifs_close_deferred_file+0x110/0x2c0 [cifs]
   ? __pfx_cifs_close_deferred_file+0x10/0x10 [cifs]
   ? __pfx_down_read+0x10/0x10
   cifs_oplock_break+0x4c1/0xa50 [cifs]
   ? __pfx_cifs_oplock_break+0x10/0x10 [cifs]
   ? lock_is_held_type+0x85/0xf0
   ? mark_held_locks+0x1a/0x90
   process_one_work+0x4c6/0x9f0
   ? find_held_lock+0x8a/0xa0
   ? __pfx_process_one_work+0x10/0x10
   ? lock_acquired+0x220/0x550
   ? __list_add_valid_or_report+0x37/0x100
   worker_thread+0x2e4/0x570
   ? __kthread_parkme+0xd1/0xf0
   ? __pfx_worker_thread+0x10/0x10
   kthread+0x17f/0x1c0
   ? kthread+0xda/0x1c0
   ? __pfx_kthread+0x10/0x10
   ret_from_fork+0x31/0x60
   ? __pfx_kthread+0x10/0x10
   ret_from_fork_asm+0x1a/0x30
   </TASK>

  Allocated by task 1118:
   kasan_save_stack+0x30/0x50
   kasan_save_track+0x14/0x30
   __kasan_kmalloc+0xaa/0xb0
   cifs_new_fileinfo+0xc8/0x9d0 [cifs]
   cifs_atomic_open+0x467/0x770 [cifs]
   lookup_open.isra.0+0x665/0x8b0
   path_openat+0x4c3/0x1380
   do_filp_open+0x167/0x270
   do_sys_openat2+0x129/0x160
   __x64_sys_creat+0xad/0xe0
   do_syscall_64+0xbb/0x1d0
   entry_SYSCALL_64_after_hwframe+0x77/0x7f

  Freed by task 83:
   kasan_save_stack+0x30/0x50
   kasan_save_track+0x14/0x30
   kasan_save_free_info+0x3b/0x70
   poison_slab_object+0xe9/0x160
   __kasan_slab_free+0x32/0x50
   kfree+0xf2/0x300
   process_one_work+0x4c6/0x9f0
   worker_thread+0x2e4/0x570
   kthread+0x17f/0x1c0
   ret_from_fork+0x31/0x60
   ret_from_fork_asm+0x1a/0x30

  Last potentially related work creation:
   kasan_save_stack+0x30/0x50
   __kasan_record_aux_stack+0xad/0xc0
   insert_work+0x29/0xe0
   __queue_work+0x5ea/0x760
   queue_work_on+0x6d/0x90
   _cifsFileInfo_put+0x3f6/0x770 [cifs]
   smb2_compound_op+0x911/0x3940 [cifs]
   smb2_set_path_size+0x228/0x270 [cifs]
   cifs_set_file_size+0x197/0x460 [cifs]
   cifs_setattr+0xd9c/0x14b0 [cifs]
   notify_change+0x4e3/0x740
   do_truncate+0xfa/0x180
   vfs_truncate+0x195/0x200
   __x64_sys_truncate+0x109/0x150
   do_syscall_64+0xbb/0x1d0
   entry_SYSCALL_64_after_hwframe+0x77/0x7f

Fixes: 71f15c9 ("smb: client: retry compound request without reusing lease")
Cc: stable@vger.kernel.org
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amboar pushed a commit that referenced this pull request Sep 13, 2024
commit d260327 upstream.

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 f900067 (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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amboar pushed a commit that referenced this pull request Sep 13, 2024
[ Upstream commit c68bbf5 ]

This adds a check before freeing the rx->skb in flush and close
functions to handle the kernel crash seen while removing driver after FW
download fails or before FW download completes.

dmesg log:
[   54.634586] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000080
[   54.643398] Mem abort info:
[   54.646204]   ESR = 0x0000000096000004
[   54.649964]   EC = 0x25: DABT (current EL), IL = 32 bits
[   54.655286]   SET = 0, FnV = 0
[   54.658348]   EA = 0, S1PTW = 0
[   54.661498]   FSC = 0x04: level 0 translation fault
[   54.666391] Data abort info:
[   54.669273]   ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000
[   54.674768]   CM = 0, WnR = 0, TnD = 0, TagAccess = 0
[   54.674771]   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
[   54.674775] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000048860000
[   54.674780] [0000000000000080] pgd=0000000000000000, p4d=0000000000000000
[   54.703880] Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP
[   54.710152] Modules linked in: btnxpuart(-) overlay fsl_jr_uio caam_jr caamkeyblob_desc caamhash_desc caamalg_desc crypto_engine authenc libdes crct10dif_ce polyval_ce polyval_generic snd_soc_imx_spdif snd_soc_imx_card snd_soc_ak5558 snd_soc_ak4458 caam secvio error snd_soc_fsl_micfil snd_soc_fsl_spdif snd_soc_fsl_sai snd_soc_fsl_utils imx_pcm_dma gpio_ir_recv rc_core sch_fq_codel fuse
[   54.744357] CPU: 3 PID: 72 Comm: kworker/u9:0 Not tainted 6.6.3-otbr-g128004619037 #2
[   54.744364] Hardware name: FSL i.MX8MM EVK board (DT)
[   54.744368] Workqueue: hci0 hci_power_on
[   54.757244] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[   54.757249] pc : kfree_skb_reason+0x18/0xb0
[   54.772299] lr : btnxpuart_flush+0x40/0x58 [btnxpuart]
[   54.782921] sp : ffff8000805ebca0
[   54.782923] x29: ffff8000805ebca0 x28: ffffa5c6cf1869c0 x27: ffffa5c6cf186000
[   54.782931] x26: ffff377b84852400 x25: ffff377b848523c0 x24: ffff377b845e7230
[   54.782938] x23: ffffa5c6ce8dbe08 x22: ffffa5c6ceb65410 x21: 00000000ffffff92
[   54.782945] x20: ffffa5c6ce8dbe98 x19: ffffffffffffffac x18: ffffffffffffffff
[   54.807651] x17: 0000000000000000 x16: ffffa5c6ce2824ec x15: ffff8001005eb857
[   54.821917] x14: 0000000000000000 x13: ffffa5c6cf1a02e0 x12: 0000000000000642
[   54.821924] x11: 0000000000000040 x10: ffffa5c6cf19d690 x9 : ffffa5c6cf19d688
[   54.821931] x8 : ffff377b86000028 x7 : 0000000000000000 x6 : 0000000000000000
[   54.821938] x5 : ffff377b86000000 x4 : 0000000000000000 x3 : 0000000000000000
[   54.843331] x2 : 0000000000000000 x1 : 0000000000000002 x0 : ffffffffffffffac
[   54.857599] Call trace:
[   54.857601]  kfree_skb_reason+0x18/0xb0
[   54.863878]  btnxpuart_flush+0x40/0x58 [btnxpuart]
[   54.863888]  hci_dev_open_sync+0x3a8/0xa04
[   54.872773]  hci_power_on+0x54/0x2e4
[   54.881832]  process_one_work+0x138/0x260
[   54.881842]  worker_thread+0x32c/0x438
[   54.881847]  kthread+0x118/0x11c
[   54.881853]  ret_from_fork+0x10/0x20
[   54.896406] Code: a9be7bfd 910003fd f9000bf3 aa0003f3 (b940d400)
[   54.896410] ---[ end trace 0000000000000000 ]---

Signed-off-by: Neeraj Sanjay Kale <neeraj.sanjaykale@nxp.com>
Tested-by: Guillaume Legoupil <guillaume.legoupil@nxp.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
amboar pushed a commit that referenced this pull request Sep 13, 2024
[ Upstream commit c3a5e3e ]

When using cachefiles, lockdep may emit something similar to the circular
locking dependency notice below.  The problem appears to stem from the
following:

 (1) Cachefiles manipulates xattrs on the files in its cache when called
     from ->writepages().

 (2) The setxattr() and removexattr() system call handlers get the name
     (and value) from userspace after taking the sb_writers lock, putting
     accesses of the vma->vm_lock and mm->mmap_lock inside of that.

 (3) The afs filesystem uses a per-inode lock to prevent multiple
     revalidation RPCs and in writeback vs truncate to prevent parallel
     operations from deadlocking against the server on one side and local
     page locks on the other.

Fix this by moving the getting of the name and value in {get,remove}xattr()
outside of the sb_writers lock.  This also has the minor benefits that we
don't need to reget these in the event of a retry and we never try to take
the sb_writers lock in the event we can't pull the name and value into the
kernel.

Alternative approaches that might fix this include moving the dispatch of a
write to the cache off to a workqueue or trying to do without the
validation lock in afs.  Note that this might also affect other filesystems
that use netfslib and/or cachefiles.

 ======================================================
 WARNING: possible circular locking dependency detected
 6.10.0-build2+ torvalds#956 Not tainted
 ------------------------------------------------------
 fsstress/6050 is trying to acquire lock:
 ffff888138fd82f0 (mapping.invalidate_lock#3){++++}-{3:3}, at: filemap_fault+0x26e/0x8b0

 but task is already holding lock:
 ffff888113f26d18 (&vma->vm_lock->lock){++++}-{3:3}, at: lock_vma_under_rcu+0x165/0x250

 which lock already depends on the new lock.

 the existing dependency chain (in reverse order) is:

 -> #4 (&vma->vm_lock->lock){++++}-{3:3}:
        __lock_acquire+0xaf0/0xd80
        lock_acquire.part.0+0x103/0x280
        down_write+0x3b/0x50
        vma_start_write+0x6b/0xa0
        vma_link+0xcc/0x140
        insert_vm_struct+0xb7/0xf0
        alloc_bprm+0x2c1/0x390
        kernel_execve+0x65/0x1a0
        call_usermodehelper_exec_async+0x14d/0x190
        ret_from_fork+0x24/0x40
        ret_from_fork_asm+0x1a/0x30

 -> #3 (&mm->mmap_lock){++++}-{3:3}:
        __lock_acquire+0xaf0/0xd80
        lock_acquire.part.0+0x103/0x280
        __might_fault+0x7c/0xb0
        strncpy_from_user+0x25/0x160
        removexattr+0x7f/0x100
        __do_sys_fremovexattr+0x7e/0xb0
        do_syscall_64+0x9f/0x100
        entry_SYSCALL_64_after_hwframe+0x76/0x7e

 -> #2 (sb_writers#14){.+.+}-{0:0}:
        __lock_acquire+0xaf0/0xd80
        lock_acquire.part.0+0x103/0x280
        percpu_down_read+0x3c/0x90
        vfs_iocb_iter_write+0xe9/0x1d0
        __cachefiles_write+0x367/0x430
        cachefiles_issue_write+0x299/0x2f0
        netfs_advance_write+0x117/0x140
        netfs_write_folio.isra.0+0x5ca/0x6e0
        netfs_writepages+0x230/0x2f0
        afs_writepages+0x4d/0x70
        do_writepages+0x1e8/0x3e0
        filemap_fdatawrite_wbc+0x84/0xa0
        __filemap_fdatawrite_range+0xa8/0xf0
        file_write_and_wait_range+0x59/0x90
        afs_release+0x10f/0x270
        __fput+0x25f/0x3d0
        __do_sys_close+0x43/0x70
        do_syscall_64+0x9f/0x100
        entry_SYSCALL_64_after_hwframe+0x76/0x7e

 -> #1 (&vnode->validate_lock){++++}-{3:3}:
        __lock_acquire+0xaf0/0xd80
        lock_acquire.part.0+0x103/0x280
        down_read+0x95/0x200
        afs_writepages+0x37/0x70
        do_writepages+0x1e8/0x3e0
        filemap_fdatawrite_wbc+0x84/0xa0
        filemap_invalidate_inode+0x167/0x1e0
        netfs_unbuffered_write_iter+0x1bd/0x2d0
        vfs_write+0x22e/0x320
        ksys_write+0xbc/0x130
        do_syscall_64+0x9f/0x100
        entry_SYSCALL_64_after_hwframe+0x76/0x7e

 -> #0 (mapping.invalidate_lock#3){++++}-{3:3}:
        check_noncircular+0x119/0x160
        check_prev_add+0x195/0x430
        __lock_acquire+0xaf0/0xd80
        lock_acquire.part.0+0x103/0x280
        down_read+0x95/0x200
        filemap_fault+0x26e/0x8b0
        __do_fault+0x57/0xd0
        do_pte_missing+0x23b/0x320
        __handle_mm_fault+0x2d4/0x320
        handle_mm_fault+0x14f/0x260
        do_user_addr_fault+0x2a2/0x500
        exc_page_fault+0x71/0x90
        asm_exc_page_fault+0x22/0x30

 other info that might help us debug this:

 Chain exists of:
   mapping.invalidate_lock#3 --> &mm->mmap_lock --> &vma->vm_lock->lock

  Possible unsafe locking scenario:

        CPU0                    CPU1
        ----                    ----
   rlock(&vma->vm_lock->lock);
                                lock(&mm->mmap_lock);
                                lock(&vma->vm_lock->lock);
   rlock(mapping.invalidate_lock#3);

  *** DEADLOCK ***

 1 lock held by fsstress/6050:
  #0: ffff888113f26d18 (&vma->vm_lock->lock){++++}-{3:3}, at: lock_vma_under_rcu+0x165/0x250

 stack backtrace:
 CPU: 0 PID: 6050 Comm: fsstress Not tainted 6.10.0-build2+ torvalds#956
 Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014
 Call Trace:
  <TASK>
  dump_stack_lvl+0x57/0x80
  check_noncircular+0x119/0x160
  ? queued_spin_lock_slowpath+0x4be/0x510
  ? __pfx_check_noncircular+0x10/0x10
  ? __pfx_queued_spin_lock_slowpath+0x10/0x10
  ? mark_lock+0x47/0x160
  ? init_chain_block+0x9c/0xc0
  ? add_chain_block+0x84/0xf0
  check_prev_add+0x195/0x430
  __lock_acquire+0xaf0/0xd80
  ? __pfx___lock_acquire+0x10/0x10
  ? __lock_release.isra.0+0x13b/0x230
  lock_acquire.part.0+0x103/0x280
  ? filemap_fault+0x26e/0x8b0
  ? __pfx_lock_acquire.part.0+0x10/0x10
  ? rcu_is_watching+0x34/0x60
  ? lock_acquire+0xd7/0x120
  down_read+0x95/0x200
  ? filemap_fault+0x26e/0x8b0
  ? __pfx_down_read+0x10/0x10
  ? __filemap_get_folio+0x25/0x1a0
  filemap_fault+0x26e/0x8b0
  ? __pfx_filemap_fault+0x10/0x10
  ? find_held_lock+0x7c/0x90
  ? __pfx___lock_release.isra.0+0x10/0x10
  ? __pte_offset_map+0x99/0x110
  __do_fault+0x57/0xd0
  do_pte_missing+0x23b/0x320
  __handle_mm_fault+0x2d4/0x320
  ? __pfx___handle_mm_fault+0x10/0x10
  handle_mm_fault+0x14f/0x260
  do_user_addr_fault+0x2a2/0x500
  exc_page_fault+0x71/0x90
  asm_exc_page_fault+0x22/0x30

Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/2136178.1721725194@warthog.procyon.org.uk
cc: Alexander Viro <viro@zeniv.linux.org.uk>
cc: Christian Brauner <brauner@kernel.org>
cc: Jan Kara <jack@suse.cz>
cc: Jeff Layton <jlayton@kernel.org>
cc: Gao Xiang <xiang@kernel.org>
cc: Matthew Wilcox <willy@infradead.org>
cc: netfs@lists.linux.dev
cc: linux-erofs@lists.ozlabs.org
cc: linux-fsdevel@vger.kernel.org
[brauner: fix minor issues]
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
amboar pushed a commit to amboar/linux that referenced this pull request Sep 18, 2024
I have done a lot of analysis for these type of devices and collaborated
quite a bit with Nick Weihs (author of the first patch submitted for this
including adding samsung_helper.c). More information can be found in the
issue on Github [1] including additional rationale and testing.

The existing implementation includes a large number of equalizer coef
values that are not necessary to actually init and enable the speaker
amps, as well as create a somewhat worse sound profile. Users have
reported "muffled" or "muddy" sound; more information about this including
my analysis of the differences can be found in the linked Github issue.

This patch refactors the "v2" version of ALC298_FIXUP_SAMSUNG_AMP to a much
simpler implementation which removes the new samsung_helper.c, reuses more
of the existing patch_realtek.c, and sends significantly fewer unnecessary
coef values (including removing all of these EQ-specific coef values).

A pcm_playback_hook is used to dynamically enable and disable the speaker
amps only when there will be audio playback; this is to match the behavior
of how the driver for these devices is working in Windows, and is
suspected but not yet tested or confirmed to help with power consumption.

Support for models with 2 speaker amps vs 4 speaker amps is controlled by
a specific quirk name for both types. A new int num_speaker_amps has been
added to alc_spec so that the hooks can know how many speaker amps to
enable or disable. This design was chosen to limit the number of places
that subsystem ids will need to be maintained: like this, they can be
maintained only once in the quirk table and there will not be another
separate list of subsystem ids to maintain elsewhere in the code.

Also updated the quirk name from ALC298_FIXUP_SAMSUNG_AMP2 to
ALC298_FIXUP_SAMSUNG_AMP_V2_.. as this is not a quirk for "Amp openbmc#2" on
ALC298 but is instead a different version of how to handle it.

More devices have been added (see Github issue for testing confirmation),
as well as a small cleanup to existing names.

[1]: thesofproject#4055 (comment)

Signed-off-by: Joshua Grisham <josh@joshuagrisham.com>
Link: https://patch.msgid.link/20240909193000.838815-1-josh@joshuagrisham.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
amboar pushed a commit to amboar/linux that referenced this pull request Sep 18, 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 openbmc#1:  select FDMA library for lan966x.

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

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

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

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

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

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

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

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

Patch openbmc#11: uses library helpers throughout.

Patch openbmc#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>
amboar pushed a commit to amboar/linux that referenced this pull request Sep 18, 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 openbmc#1 was attempted in RFC v1. RFC v2 implements approach openbmc#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>
amboar pushed a commit to amboar/linux that referenced this pull request Sep 18, 2024
…git/netfilter/nf

Pablo Neira Ayuso says:

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

The following batch contains two fixes from Florian Westphal:

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

Patch openbmc#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>
amboar pushed a commit to amboar/linux that referenced this pull request Sep 18, 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 openbmc#1 adds the new DSCP attribute but rejects its usage.

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

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

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

Link: https://patch.msgid.link/20240911093748.3662015-1-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
amboar pushed a commit to amboar/linux that referenced this pull request Sep 18, 2024
Nelson Escobar says:

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

Patch openbmc#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 openbmc#2: Collect per queue statistics

Patch openbmc#3: Report per queue stats in netdev qstats

Patch openbmc#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>
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