installer setuid fallback for perf and slabinfo plugins

[ilyam8]

Summary

ssia, noticed the problem when building a static version locally.

@Ferroin setcap is not available in our helper images. It is ok to setuid these plugins because setuid bit will be overwritten in install-or-update.sh (static build).

[/usr/src/netdata]# sh -c setcap cap_perfmon+ep "/opt/netdata/usr/libexec/netdata/plugins.d/perf.plugin" || setcap cap_sys_admin+ep "/opt/netdata/usr/libexec/netdata/plugins.d/perf.plugin"
sh: setcap: not found
sh: setcap: not found
 FAILED  ''

[/usr/src/netdata]# setcap cap_dac_read_search+ep /opt/netdata/usr/libexec/netdata/plugins.d/slabinfo.plugin
./netdata-installer.sh: line 344: setcap: not found
 FAILED  ''

Test Plan

• install from source.
• build static and install.

Check slabinfo/perf plugins permissions/capabilities.

Additional Information

For users: How does this change affect me?

[thiagoftsm]

Current master on my environment is setting:

bash-5.2# ls -l /usr/libexec/netdata/plugins.d/slabinfo.plugin /usr/libexec/netdata/plugins.d/perf.plugin 
-rwxr-x--- 1 root netdata 2197008 Aug 16 14:54 /usr/libexec/netdata/plugins.d/perf.plugin
-rwxr-x--- 1 root netdata 2188272 Aug 16 14:54 /usr/libexec/netdata/plugins.d/slabinfo.plugin

And this PR is keeping permissions with plugin running normally:

bash-5.2# ls -l /usr/libexec/netdata/plugins.d/slabinfo.plugin /usr/libexec/netdata/plugins.d/perf.plugin 
-rwxr-x--- 1 root netdata 2647128 Aug 16 14:42 /usr/libexec/netdata/plugins.d/perf.plugin
-rwxr-x--- 1 root netdata 2638432 Aug 16 14:42 /usr/libexec/netdata/plugins.d/slabinfo.plugin
bash-5.2# netdata
2023-08-16 14:43:58: netdata IERR  : MAIN : (0048@daemon/common.c     :get_netdata_cpu): System CPUs: 4, (system: 4, cgroups cpuset v1: 4, cgroups cpuset v2: 0, netdata.conf: 4)
bash-5.2# grep perf /var/log/netdata/*
/var/log/netdata/access.log:2023-08-16 14:44:55: 2: 1474 '[localhost]:46696' 'DATA' (sent/all = 2310/15036 bytes -85%, prep/sent/total = 0.42/0.15/0.57 ms) 200 '//api/v2/data?points=304&format=json2&time_group=average&time_resampling=0&after=1692196196&before=1692197096&group_by%5B0%5D=dimension&group_by_label%5B0%5D=&aggregation%5B0%5D=sum&options=jsonwrap%7Cnonzero%7Cflip%7Cms%7Cjw-anomaly-rates%7Cminify&contexts=*&scope_contexts=perf.cpu_cycles&scope_nodes=*&nodes=*&instances=*&dimensions=*&labels=*'
/var/log/netdata/access.log:2023-08-16 14:44:58: 2: 1474 '[localhost]:46696' 'DATA' (sent/all = 2327/15065 bytes -85%, prep/sent/total = 0.52/0.20/0.72 ms) 200 '//api/v2/data?points=304&format=json2&time_group=average&time_resampling=0&after=1692196199&before=1692197099&group_by%5B0%5D=dimension&group_by_label%5B0%5D=&aggregation%5B0%5D=sum&options=jsonwrap%7Cnonzero%7Cflip%7Cms%7Cjw-anomaly-rates%7Cminify&contexts=*&scope_contexts=perf.cpu_cycles&scope_nodes=*&nodes=*&instances=*&dimensions=*&labels=*'
/var/log/netdata/collector.log:2023-08-16 14:44:04: go.d ERROR: prometheus[performance_counters_exporter_local] Get "http://127.0.0.1:9358/metrics": dial tcp 127.0.0.1:9358: connect: connection refused
/var/log/netdata/collector.log:2023-08-16 14:44:04: go.d ERROR: prometheus[performance_counters_exporter_local] check failed
/var/log/netdata/collector.log:2023-08-16 14:44:04: go.d ERROR: prometheus[windows_perflib_exporter_local] Get "http://127.0.0.1:9432/metrics": dial tcp 127.0.0.1:9432: connect: connection refused
/var/log/netdata/collector.log:2023-08-16 14:44:04: go.d ERROR: prometheus[windows_perflib_exporter_local] check failed
/var/log/netdata/collector.log:2023-08-16 14:44:04: go.d ERROR: prometheus[iperf3_exporter_local] Get "http://127.0.0.1:9579/metrics": dial tcp 127.0.0.1:9579: connect: connection refused
/var/log/netdata/collector.log:2023-08-16 14:44:04: go.d ERROR: prometheus[iperf3_exporter_local] check failed
/var/log/netdata/collector.log:2023-08-16 14:44:04: go.d ERROR: prometheus[opvizor_performance_analyzer_process_exporter_local] Get "http://127.0.0.1:9585/metrics": dial tcp 127.0.0.1:9585: connect: connection refused
/var/log/netdata/collector.log:2023-08-16 14:44:04: go.d ERROR: prometheus[opvizor_performance_analyzer_process_exporter_local] check failed
/var/log/netdata/error.log:2023-08-16 14:44:02: netdata INFO  : PD[perf] : (0250@libnetdata/threads/t:netdata_thread_): thread created with task id 1498
/var/log/netdata/error.log:2023-08-16 14:44:02: netdata INFO  : PD[perf] : (0210@libnetdata/threads/t:thread_set_name): set name of thread 1498 to PD[perf]
/var/log/netdata/error.log:2023-08-16 14:44:02: netdata INFO  : MAIN : (2115@daemon/main.c       :main           ): NETDATA STARTUP: completed in 4291 ms. Enjoy real-time performance monitoring!
/var/log/netdata/error.log:2023-08-16 14:44:02: netdata INFO  : PD[perf] : (0160@collectors/plugins.d:pluginsd_worker): PLUGINSD: 'host:hades' connected to '/usr/libexec/netdata/plugins.d/perf.plugin' running on pid 1510
/var/log/netdata/error.log:2023-08-16 14:44:55: netdata IERR  : WEB[1] : (0416@database/ram/rrddim_:rrddim_query_fi): QUERY: query for chart 'perf.cpu_cycles' dimension 'cpu' has been stopped unfinished
/var/log/netdata/error.log:2023-08-16 14:44:55: netdata IERR  : WEB[1] : (0416@database/ram/rrddim_:rrddim_query_fi): QUERY: query for chart 'perf.cpu_cycles' dimension 'ref_cpu' has been stopped unfinished
/var/log/netdata/error.log:2023-08-16 14:44:58: netdata IERR  : WEB[1] : (0416@database/ram/rrddim_:rrddim_query_fi): QUERY: query for chart 'perf.cpu_cycles' dimension 'cpu' has been stopped unfinished
/var/log/netdata/error.log:2023-08-16 14:44:58: netdata IERR  : WEB[1] : (0416@database/ram/rrddim_:rrddim_query_fi): QUERY: query for chart 'perf.cpu_cycles' dimension 'ref_cpu' has been stopped unfinished

LGTM!