bpf,perf: Fix invalid prog_array access in perf_event_detach_bpf_prog
Summary
bpf,perf: Fix invalid prog_array access in perf_event_detach_bpf_prog
Original description
The description as published by the source.
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 packages
Fix status by distribution
Fixed packages published by each distribution for this CVE
- BellSoft Alpaquita BELL-CVE-2024-56665 linux-lts Fixed in: 6.1.121-r0
- Debian DEBIAN-CVE-2024-56665 linux Fixed in: 6.1.123-1
- Ubuntu UBUNTU-CVE-2024-56665 linux-hwe-edge
References
- advisory github.com
- advisory nvd.nist.gov
- package git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web lists.debian.org