1.5 KiB
CVE-2024-56665
Description
In the Linux kernel, the following vulnerability has been resolved:bpf,perf: Fix invalid prog_array access in perf_event_detach_bpf_progSyzbot 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 NULLThe fix makes sure the perf_event_detach_bpf_prog checks prog_arrayis valid before it tries to remove the bpf program from it.[1] https://lore.kernel.org/bpf/Z1MR6dCIKajNS6nU@krava/T/#m91dbf0688221ec7a7fc95e896a7ef9ff93b0b8ad
POC
Reference
No PoCs from references.