7.3-stable review patch. If anyone has any objections, please let me know. ------------------ From: David Carlier commit 66877a312ae3c2c3d849e82e882f642ffd4ec3e2 upstream. trace_module_record() walks ftrace_trace_arrays from the module notifier without trace_types_lock. A concurrent rmdir of an instance removes it from the list and frees it under that lock, so a module load or unload can walk into a freed trace_array. Cc: stable@vger.kernel.org Fixes: 5f3719f697c3 ("tracing: Update modules to persistent instances when loaded") Link: https://patch.msgid.link/20261016061638.214847-1-devnexen@gmail.com Signed-off-by: David Carlier Signed-off-by: Steven Rostedt Signed-off-by: Greg Kroah-Hartman --- kernel/trace/trace.c | 2 ++ 1 file changed, 2 insertions(+) --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -9263,6 +9263,8 @@ static void trace_module_record(struct m struct trace_array *tr; unsigned long flags; + guard(mutex)(&trace_types_lock); + list_for_each_entry(tr, &ftrace_trace_arrays, list) { flags = tr->flags & (TRACE_ARRAY_FL_BOOT | TRACE_ARRAY_FL_LAST_BOOT); /* Update any persistent trace array that has already been started */