tracing/user_events: Hold event_mutex during dyn_event_add

Make sure the event_mutex is properly held during dyn_event_add call. This is required when adding dynamic events.

Reported-by Mathieu Desnoyers <[email protected]>

Signed-off-by Beau Belgrave <[email protected]>

---
 kernel/trace/trace_events_user.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

kernel/trace/trace_events_user.c +6 -2

index 8b3d241a31c2..61d78d64bdf0 100644
@@ -1165,11 +1165,11 @@ static int user_event_parse(char *name, char *args, char *flags,
 #endif
 
 	mutex_lock(&event_mutex);
+
 	ret = user_event_trace_register(user);
-	mutex_unlock(&event_mutex);
 
 	if (ret)
-		goto put_user;
+		goto put_user_lock;
 
 	user->index = index;
 

@@ -1181,8 +1181,12 @@ static int user_event_parse(char *name, char *args, char *flags,
 	set_bit(user->index, page_bitmap);
 	hash_add(register_table, &user->node, key);
 
+	mutex_unlock(&event_mutex);
+
 	*newuser = user;
 	return 0;
+put_user_lock:
+	mutex_unlock(&event_mutex);
 put_user:
 	user_event_destroy_fields(user);
 	user_event_destroy_validators(user);

base-commit: c87857e214862a125208a4b1a510839d0c5a1bd4

Signature · 1 line

2.25.1