Memory allocated with trigger_data_alloc() require trigger_data_free() for proper cleanup.
Replace kfree() with trigger_data_free() to fix this.
Found via static analysis and code review.
Fixes: e1f187d09e11 ("tracing: Have existing event_command.parse() implementations use helpers") Cc: stable@vger.kernel.org Signed-off-by: Miaoqian Lin linmq006@gmail.com --- kernel/trace/trace_events_hist.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index 5e6e70540eef..f9886fff7123 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -6902,7 +6902,7 @@ static int event_hist_trigger_parse(struct event_command *cmd_ops,
remove_hist_vars(hist_data);
- kfree(trigger_data); + trigger_data_free(trigger_data);
destroy_hist_data(hist_data); goto out;
On Thu, 11 Dec 2025 14:00:58 +0400 Miaoqian Lin linmq006@gmail.com wrote:
@@ -6902,7 +6902,7 @@ static int event_hist_trigger_parse(struct event_command *cmd_ops, remove_hist_vars(hist_data);
- kfree(trigger_data);
- trigger_data_free(trigger_data);
destroy_hist_data(hist_data); goto out;
The above code has this:
out_free: event_trigger_reset_filter(cmd_ops, trigger_data);
remove_hist_vars(hist_data);
kfree(trigger_data);
destroy_hist_data(hist_data); goto out;
Where we have;
void event_trigger_reset_filter(struct event_command *cmd_ops, struct event_trigger_data *trigger_data) { if (cmd_ops->set_filter) cmd_ops->set_filter(NULL, trigger_data, NULL); }
And trigger_data_free() starts with:
void trigger_data_free(struct event_trigger_data *data) { if (data->cmd_ops->set_filter) data->cmd_ops->set_filter(NULL, data, NULL);
thus it looks like the current code is an open coded version of trigger_data_free() without synchronization (as it isn't needed here).
Thus, I believe this is more of a clean up and not a fix (something to go into the next merge window and not the current -rc release).
And the code can be changed to also remove the event_trigger_reset_filter() call.
-- Steve
linux-stable-mirror@lists.linaro.org
-
Miaoqian Lin -
Steven Rostedt