CVE-2024-56665: bpf,perf: Fix invalid prog_array access in perf_event_detach_bpf_prog

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-12-27 · updated 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: bpf,perf: Fix invalid prog_array access in perf_event_detach_bpf_prog Syzbot reported [1] crash that happens for following tracing scenario: - create tracepoint perf event with attr.inherit=1, attach it to the process and set bpf program to it - attached process forks -> chid creates inherited event the new child event shares the parent's bpf program and tp_event (hence prog_array) which is global for tracepoint - exit both process and its child -> release both events - first perf_event_detach_bpf_prog call will release tp_event->prog_array and second perf_event_detach_bpf_prog will crash, because tp_event->prog_array is NULL The fix makes sure the perf_event_detach_bpf_prog checks prog_array is valid before it tries to remove the bpf program from it. [1] https://lore.kernel.org/bpf/Z1MR6dCIKajNS6nU@krava/T/#m91dbf0688221ec7a7fc95e896a7ef9ff93b0b8ad

Affected products

Linux kernel: from 5.15.170 before 5.16; from 6.1.115 before 6.1.121; from 6.6.59 before 6.6.67; from 6.11.6 before 6.12.6; 6.13-rc1, 6.13-rc2 — fixed in 5.16, 6.1.121, 6.12.6, 6.6.67

How to fix

Upgrade to a fixed version: Linux kernel 5.16, 6.1.121, 6.12.6, 6.6.67. Check the vendor advisory for mitigations.

References

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