The following commit has been merged into the perf/core branch of tip:
Commit-ID: 26700b1359a121c42eb7517e053a86b07466b79b
Gitweb: https://git.kernel.org/tip/26700b1359a121c42eb7517e053a86b07466b79b
Author: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
AuthorDate: Mon, 04 Nov 2024 14:39:22 +01:00
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitterDate: Sat, 01 Mar 2025 20:06:47 +01:00
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: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Alexei Starovoitov <ast@xxxxxxxxxx>
Cc: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
Cc: Andrii Nakryiko <andrii@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20241104135518.978956692@xxxxxxxxxxxxx
---
kernel/events/core.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 525c64e..ab4e497 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -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;
|