[PATCH tip/core/rcu 1/3] rcu: Record kvfree_call_rcu() call stack for KASAN

[paulmck]

From: Zqiang <qiang.zhang@xxxxxxxxxxxxx>

This commit adds a call to kasan_record_aux_stack() in kvfree_call_rcu()
in order to record the call stack of the code that caused the object
to be freed.  Please note that this function does not update the
allocated/freed state, which is important because RCU readers might
still be referencing this object.

Acked-by: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@xxxxxxxxx>
Signed-off-by: Zqiang <qiang.zhang@xxxxxxxxxxxxx>
Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
---
 kernel/rcu/tree.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 40e5e3d..2db736c 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -3498,6 +3498,7 @@ void kvfree_call_rcu(struct rcu_head *head, rcu_callback_t func)
 		goto unlock_return;
 	}
 
+	kasan_record_aux_stack(ptr);
 	success = kvfree_call_rcu_add_ptr_to_bulk(krcp, ptr);
 	if (!success) {
 		run_page_cache_worker(krcp);
-- 
2.9.5