Commit c5b96789 authored by Peter Zijlstra's avatar Peter Zijlstra Committed by Ingo Molnar
Browse files

perf/bpf: Robustify perf_event_free_bpf_prog() 



Ensure perf_event_free_bpf_prog() is safe to call a second time;
notably without making any references to event->pmu when there is no
prog left.

Note: perf_event_detach_bpf_prog() might leave a stale event->prog

Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
Reviewed-by: default avatarRavi Bangoria <ravi.bangoria@amd.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20241104135518.978956692@infradead.org
parent adc38b4c

kernel/events/core.c

+3 −0
Original line number Diff line number Diff line
@@ -10905,6 +10905,9 @@ int perf_event_set_bpf_prog(struct perf_event *event, struct bpf_prog *prog, 


void perf_event_free_bpf_prog(struct perf_event *event)

{

	if (!event->prog)

		return;



	if (!perf_event_is_tracing(event)) {

		perf_event_free_bpf_handler(event);

		return;