From e5b3dd2d92c4511e81f6e4ec9c5bb7ad25e03d13 Mon Sep 17 00:00:00 2001 From: Wentao_Liang Date: Thu, 28 Jul 2022 19:39:19 +0800 Subject: [PATCH] drivers:md:fix a potential use-after-free bug [ Upstream commit 104212471b1c1817b311771d817fb692af983173 ] In line 2884, "raid5_release_stripe(sh);" drops the reference to sh and may cause sh to be released. However, sh is subsequently used in lines 2886 "if (sh->batch_head && sh != sh->batch_head)". This may result in an use-after-free bug. It can be fixed by moving "raid5_release_stripe(sh);" to the bottom of the function. Signed-off-by: Wentao_Liang Signed-off-by: Song Liu Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- drivers/md/raid5.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index dad426cc0f90..6f04473f0838 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -2670,10 +2670,10 @@ static void raid5_end_write_request(struct bio *bi) if (!test_and_clear_bit(R5_DOUBLE_LOCKED, &sh->dev[i].flags)) clear_bit(R5_LOCKED, &sh->dev[i].flags); set_bit(STRIPE_HANDLE, &sh->state); - raid5_release_stripe(sh); if (sh->batch_head && sh != sh->batch_head) raid5_release_stripe(sh->batch_head); + raid5_release_stripe(sh); } static void raid5_error(struct mddev *mddev, struct md_rdev *rdev)