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Improper Input Validation Affecting perf package, versions *

Severity

 Recommended
0.0
medium
0
10

Based on CentOS security rating.

Threat Intelligence

EPSS
0.03% (8th percentile)

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  • Snyk IDSNYK-CENTOS6-PERF-10463952
  • published20 Jun 2025
  • disclosed18 Jun 2025
Report a new vulnerability Found a mistake?

Introduced: 18 Jun 2025

NewCVE-2022-50008  (opens in a new tab)
CWE-20  (opens in a new tab)

How to fix?

There is no fixed version for Centos:6 perf.

NVD Description

Note: Versions mentioned in the description apply only to the upstream perf package and not the perf package as distributed by Centos. See How to fix? for Centos:6 relevant fixed versions and status.

In the Linux kernel, the following vulnerability has been resolved:

kprobes: don't call disarm_kprobe() for disabled kprobes

The assumption in __disable_kprobe() is wrong, and it could try to disarm an already disarmed kprobe and fire the WARN_ONCE() below. [0] We can easily reproduce this issue.

  1. Write 0 to /sys/kernel/debug/kprobes/enabled.

echo 0 > /sys/kernel/debug/kprobes/enabled

  1. Run execsnoop. At this time, one kprobe is disabled.

/usr/share/bcc/tools/execsnoop &

[1] 2460 PCOMM PID PPID RET ARGS

cat /sys/kernel/debug/kprobes/list

ffffffff91345650 r __x64_sys_execve+0x0 [FTRACE] ffffffff91345650 k __x64_sys_execve+0x0 [DISABLED][FTRACE]

  1. Write 1 to /sys/kernel/debug/kprobes/enabled, which changes kprobes_all_disarmed to false but does not arm the disabled kprobe.

echo 1 > /sys/kernel/debug/kprobes/enabled

cat /sys/kernel/debug/kprobes/list

ffffffff91345650 r __x64_sys_execve+0x0 [FTRACE] ffffffff91345650 k __x64_sys_execve+0x0 [DISABLED][FTRACE]

  1. Kill execsnoop, when __disable_kprobe() calls disarm_kprobe() for the disabled kprobe and hits the WARN_ONCE() in __disarm_kprobe_ftrace().

fg

/usr/share/bcc/tools/execsnoop ^C

Actually, WARN_ONCE() is fired twice, and __unregister_kprobe_top() misses some cleanups and leaves the aggregated kprobe in the hash table. Then, __unregister_trace_kprobe() initialises tk->rp.kp.list and creates an infinite loop like this.

aggregated kprobe.list -> kprobe.list -. ^ | '.__.'

In this situation, these commands fall into the infinite loop and result in RCU stall or soft lockup.

cat /sys/kernel/debug/kprobes/list : show_kprobe_addr() enters into the infinite loop with RCU.

/usr/share/bcc/tools/execsnoop : warn_kprobe_rereg() holds kprobe_mutex, and __get_valid_kprobe() is stuck in the loop.

To avoid the issue, make sure we don't call disarm_kprobe() for disabled kprobes.

[0] Failed to disarm kprobe-ftrace at __x64_sys_execve+0x0/0x40 (error -2) WARNING: CPU: 6 PID: 2460 at kernel/kprobes.c:1130 __disarm_kprobe_ftrace.isra.19 (kernel/kprobes.c:1129) Modules linked in: ena CPU: 6 PID: 2460 Comm: execsnoop Not tainted 5.19.0+ #28 Hardware name: Amazon EC2 c5.2xlarge/, BIOS 1.0 10/16/2017 RIP: 0010:__disarm_kprobe_ftrace.isra.19 (kernel/kprobes.c:1129) Code: 24 8b 02 eb c1 80 3d c4 83 f2 01 00 75 d4 48 8b 75 00 89 c2 48 c7 c7 90 fa 0f 92 89 04 24 c6 05 ab 83 01 e8 e4 94 f0 ff <0f> 0b 8b 04 24 eb b1 89 c6 48 c7 c7 60 fa 0f 92 89 04 24 e8 cc 94 RSP: 0018:ffff9e6ec154bd98 EFLAGS: 00010282 RAX: 0000000000000000 RBX: ffffffff930f7b00 RCX: 0000000000000001 RDX: 0000000080000001 RSI: ffffffff921461c5 RDI: 00000000ffffffff RBP: ffff89c504286da8 R08: 0000000000000000 R09: c0000000fffeffff R10: 0000000000000000 R11: ffff9e6ec154bc28 R12: ffff89c502394e40 R13: ffff89c502394c00 R14: ffff9e6ec154bc00 R15: 0000000000000000 FS: 00007fe800398740(0000) GS:ffff89c812d80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c00057f010 CR3: 0000000103b54006 CR4: 00000000007706e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: <TASK> __disable_kprobe (kernel/kprobes.c:1716) disable_kprobe (kernel/kprobes.c:2392) __disable_trace_kprobe (kernel/trace/trace_kprobe.c:340) disable_trace_kprobe (kernel/trace/trace_kprobe.c:429) perf_trace_event_unreg.isra.2 (./include/linux/tracepoint.h:93 kernel/trace/trace_event_perf.c:168) perf_kprobe_destroy (kernel/trace/trace_event_perf.c:295) _free_event (kernel/events/core.c:4971) perf_event_release_kernel (kernel/events/core.c:5176) perf_release (kernel/events/core.c:5186) __fput (fs/file_table.c:321) task_work_run (./include/linux/ ---truncated---

CVSS Base Scores

version 3.1