diff options
| author | Ali Ahmet Memiş <aliamemis@disroot.org> | 2026-09-11 18:56:47 +0300 |
|---|---|---|
| committer | Steven Rostedt <rostedt@goodmis.org> | 2026-09-12 13:27:41 -0400 |
| commit | bcfe2816e6ec46c3f4c58aa4264476665ddb3f69 (patch) | |
| tree | ad4f8d85fb6280eb6cf9ef6b194977dbfa8a75b8 | |
| parent | b4dcc18b97913888e8d009624e07c8014ce41b84 (diff) | |
tracing: Don't dereference trace_event_file in deferred trigger free
The enable_event trigger defers trace_event_put_ref() to the
trigger free kthread, but the trace_event_file can already be freed
when the instance is removed.
Keep the trace_event_call directly in enable_trigger_data so the
deferred free does not access the freed trace_event_file.
Cc: stable@vger.kernel.org
Fixes: e091351b3881 ("tracing: Delay module ref count for "enable_event" trigger")
Reported-by: Alexander Gordeev <agordeev@linux.ibm.com>
Closes: https://lore.kernel.org/all/20260828134340.2501683A24-agordeev@linux.ibm.com/
Link: https://patch.msgid.link/20260911155650.354844-1-aliamemis@disroot.org
Signed-off-by: Ali Ahmet Memiş <aliamemis@disroot.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| -rw-r--r-- | kernel/trace/trace.h | 1 | ||||
| -rw-r--r-- | kernel/trace/trace_events_trigger.c | 4 |
2 files changed, 4 insertions, 1 deletions
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index bd3c8f80300f..3749485a7d85 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -1953,6 +1953,7 @@ struct event_trigger_data { struct enable_trigger_data { struct trace_event_file *file; + struct trace_event_call *call; bool enable; bool hist; }; diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c index 149300cc5e8a..4d2fde996c0f 100644 --- a/kernel/trace/trace_events_trigger.c +++ b/kernel/trace/trace_events_trigger.c @@ -1728,7 +1728,8 @@ static void enable_trigger_private_data_free(struct event_trigger_data *data) { struct enable_trigger_data *enable_data = data->private_data; - trace_event_put_ref(enable_data->file->event_call); + /* The file may already be freed here, only the call is kept alive */ + trace_event_put_ref(enable_data->call); kfree(enable_data); } @@ -1801,6 +1802,7 @@ int event_enable_trigger_parse(struct event_command *cmd_ops, enable_data->hist = hist; enable_data->enable = enable; enable_data->file = event_enable_file; + enable_data->call = event_enable_file->event_call; trigger_data = trigger_data_alloc(cmd_ops, cmd, param, enable_data); if (!trigger_data) |