Commit 63444b7617c0 for kernel
commit 63444b7617c09aeed36282e061c3f80818f2b600
Author: Leon Hwang <leon.hwang@linux.dev>
Date: Thu Jul 30 23:04:08 2026 +0800
ftrace: Protect direct_functions in ftrace_find_rec_direct
Fix accessing the __rcu pointer direct_functions with RCU protection.
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260730150411.88667-2-leon.hwang@linux.dev
Fixes: d05cb470663a ("ftrace: Fix modification of direct_function hash while in use")
Acked-by: Jiri Olsa <jolsa@kernel.org>
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Leon Hwang <leon.hwang@linux.dev>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 6c47a94f5924..c5d1d0d42ccc 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -2645,7 +2645,8 @@ unsigned long ftrace_find_rec_direct(unsigned long ip)
{
struct ftrace_func_entry *entry;
- entry = __ftrace_lookup_ip(direct_functions, ip);
+ guard(preempt_notrace)();
+ entry = __ftrace_lookup_ip(rcu_dereference_sched(direct_functions), ip);
if (!entry)
return 0;