* Re: [PATCH] tracing: Use more common error handling code in event_enable_trigger_parse()
2026-06-16 20:33 [PATCH] tracing: Use more common error handling code in event_enable_trigger_parse() Markus Elfring
@ 2026-07-01 20:37 ` Steven Rostedt
0 siblings, 0 replies; 2+ messages in thread
From: Steven Rostedt @ 2026-07-01 20:37 UTC (permalink / raw)
To: Markus Elfring
Cc: linux-trace-kernel, Masami Hiramatsu, Mathieu Desnoyers,
Tom Zanussi, LKML, kernel-janitors
On Tue, 16 Jun 2026 22:33:17 +0200
Markus Elfring <Markus.Elfring@web.de> wrote:
> From: Markus Elfring <elfring@users.sourceforge.net>
> Date: Tue, 16 Jun 2026 22:22:52 +0200
>
> Use an additional label so that a bit of exception handling can be better
> reused at the end of this function implementation.
>
> This issue was detected by using the Coccinelle software.
>
> Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
> ---
> kernel/trace/trace_events_trigger.c | 10 ++++------
> 1 file changed, 4 insertions(+), 6 deletions(-)
>
> diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c
> index 655db2e82513..7e17dd6d5b50 100644
> --- a/kernel/trace/trace_events_trigger.c
> +++ b/kernel/trace/trace_events_trigger.c
> @@ -1789,17 +1789,14 @@ int event_enable_trigger_parse(struct event_command *cmd_ops,
> enable_data->file = event_enable_file;
>
> trigger_data = trigger_data_alloc(cmd_ops, cmd, param, enable_data);
> - if (!trigger_data) {
> - kfree(enable_data);
> - return ret;
> - }
> + if (!trigger_data)
> + goto out_free_enable_data;
>
> if (remove) {
> event_trigger_unregister(cmd_ops, file, glob+1, trigger_data);
> kfree(trigger_data);
> - kfree(enable_data);
> ret = 0;
> - return ret;
> + goto out_free_enable_data;
> }
>
> /* Up the trigger_data count to make sure nothing frees it on failure */
> @@ -1837,6 +1834,7 @@ int event_enable_trigger_parse(struct event_command *cmd_ops,
> out_free:
> event_trigger_reset_filter(cmd_ops, trigger_data);
> event_trigger_free(trigger_data);
> +out_free_enable_data:
> kfree(enable_data);
Ug, let's not add more error labels now that we have cleanup code.
Untested, but this would be cleaner:
diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c
index 655db2e82513..7da096acaf2b 100644
--- a/kernel/trace/trace_events_trigger.c
+++ b/kernel/trace/trace_events_trigger.c
@@ -1739,7 +1739,7 @@ int event_enable_trigger_parse(struct event_command *cmd_ops,
char *glob, char *cmd, char *param_and_filter)
{
struct trace_event_file *event_enable_file;
- struct enable_trigger_data *enable_data;
+ struct enable_trigger_data *enable_data __free(kfree) = NULL;
struct event_trigger_data *trigger_data;
struct trace_array *tr = file->tr;
char *param, *filter;
@@ -1789,17 +1789,13 @@ int event_enable_trigger_parse(struct event_command *cmd_ops,
enable_data->file = event_enable_file;
trigger_data = trigger_data_alloc(cmd_ops, cmd, param, enable_data);
- if (!trigger_data) {
- kfree(enable_data);
+ if (!trigger_data)
return ret;
- }
if (remove) {
event_trigger_unregister(cmd_ops, file, glob+1, trigger_data);
kfree(trigger_data);
- kfree(enable_data);
- ret = 0;
- return ret;
+ return 0;
}
/* Up the trigger_data count to make sure nothing frees it on failure */
@@ -1829,6 +1825,7 @@ int event_enable_trigger_parse(struct event_command *cmd_ops,
goto out_disable;
event_trigger_free(trigger_data);
+ no_free_ptr(enable_free);
return ret;
out_disable:
trace_event_enable_disable(event_enable_file, 0, 1);
@@ -1837,7 +1834,6 @@ int event_enable_trigger_parse(struct event_command *cmd_ops,
out_free:
event_trigger_reset_filter(cmd_ops, trigger_data);
event_trigger_free(trigger_data);
- kfree(enable_data);
return ret;
}
-- Steve
^ permalink raw reply related [flat|nested] 2+ messages in thread