6.6-stable review patch. If anyone has any objections, please let me know.
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From: Jiri Olsa jolsa@kernel.org
[ Upstream commit 0ee288e69d033850bc87abe0f9cc3ada24763d7f ]
Peter reported that perf_event_detach_bpf_prog might skip to release the bpf program for -ENOENT error from bpf_prog_array_copy.
This can't happen because bpf program is stored in perf event and is detached and released only when perf event is freed.
Let's drop the -ENOENT check and make sure the bpf program is released in any case.
Fixes: 170a7e3ea070 ("bpf: bpf_prog_array_copy() should return -ENOENT if exclude_prog not found") Reported-by: Peter Zijlstra peterz@infradead.org Signed-off-by: Jiri Olsa jolsa@kernel.org Signed-off-by: Andrii Nakryiko andrii@kernel.org Link: https://lore.kernel.org/bpf/20241023200352.3488610-1-jolsa@kernel.org
Closes: https://lore.kernel.org/lkml/20241022111638.GC16066@noisy.programming.kicks-... Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/trace/bpf_trace.c | 2 -- 1 file changed, 2 deletions(-)
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index ecc86a595b754..9064f75de7e46 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -2217,8 +2217,6 @@ void perf_event_detach_bpf_prog(struct perf_event *event)
old_array = bpf_event_rcu_dereference(event->tp_event->prog_array); ret = bpf_prog_array_copy(old_array, event->prog, NULL, 0, &new_array); - if (ret == -ENOENT) - goto unlock; if (ret < 0) { bpf_prog_array_delete_safe(old_array, event->prog); } else {