LKML Archive on
help / color / mirror / Atom feed
From: Wentao_Liang <>
	Wentao_Liang <>
Subject: [PATCH] drivers:md:fix a potential use-after-free bug
Date: Thu, 28 Jul 2022 19:39:19 +0800	[thread overview]
Message-ID: <> (raw)

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.

The bug has been confirmed by Song on 2021-08-14. Now, I resend this
patch with my real name. I hope the patch can be updated in a near

Signed-off-by: Wentao_Liang <>
 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 5d09256d7f81..93fcbeac5096 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -2881,10 +2881,10 @@ 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);
 static void raid5_error(struct mddev *mddev, struct md_rdev *rdev)

             reply	other threads:[~2022-07-28  3:40 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-07-28 11:39 Wentao_Liang [this message]
2022-07-28  5:55 ` Song Liu
     [not found] <>
2021-08-13 16:16 ` Song Liu
2021-08-17  7:47   ` Guoqing Jiang

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \ \ \ \ \ \
    --subject='Re: [PATCH] drivers:md:fix a potential use-after-free bug' \

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).