ftrace: Protect direct_functions in ftrace_find_rec_direct

Fix accessing the __rcu pointer direct_functions with RCU protection.

Leon Hwang committed 3 months ago

Commit 63444b71 parent f0ece161 file · +2 −1Browse files

Unified · Split

@@ -2645,7 +2645,8 @@ unsigned long ftrace_find_rec_direct(unsigned long ip) · 2644 unmodified lines
2645	{	2645	{
2646	struct ftrace_func_entry *entry;	2646	struct ftrace_func_entry *entry;
2647		2647
2648	entry = __ftrace_lookup_ip(direct_functions, ip);	2648	guard(preempt_notrace)();
		2649	entry = __ftrace_lookup_ip(rcu_dereference_sched(direct_functions), ip);
2649	if (!entry)	2650	if (!entry)
2650	return 0;	2651	return 0;
2651		2652