From: Barnabás Pőcze Date: Mon, 14 Nov 2022 19:54:23 +0000 (+0000) Subject: timerqueue: Use rb_entry_safe() in timerqueue_getnext() X-Git-Tag: v5.15.92~1381 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=07b8659b8e5b3a4a68cc9afc3e0577a7ef30f571;p=platform%2Fkernel%2Flinux-rpi.git timerqueue: Use rb_entry_safe() in timerqueue_getnext() [ Upstream commit 2f117484329b233455ee278f2d9b0a4356835060 ] When `timerqueue_getnext()` is called on an empty timer queue, it will use `rb_entry()` on a NULL pointer, which is invalid. Fix that by using `rb_entry_safe()` which handles NULL pointers. This has not caused any issues so far because the offset of the `rb_node` member in `timerqueue_node` is 0, so `rb_entry()` is essentially a no-op. Fixes: 511885d7061e ("lib/timerqueue: Rely on rbtree semantics for next timer") Signed-off-by: Barnabás Pőcze Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/r/20221114195421.342929-1-pobrn@protonmail.com Signed-off-by: Sasha Levin --- diff --git a/include/linux/timerqueue.h b/include/linux/timerqueue.h index 9388408..adc80e2 100644 --- a/include/linux/timerqueue.h +++ b/include/linux/timerqueue.h @@ -35,7 +35,7 @@ struct timerqueue_node *timerqueue_getnext(struct timerqueue_head *head) { struct rb_node *leftmost = rb_first_cached(&head->rb_root); - return rb_entry(leftmost, struct timerqueue_node, node); + return rb_entry_safe(leftmost, struct timerqueue_node, node); } static inline void timerqueue_init(struct timerqueue_node *node)