This is a note to let you know that I've just added the patch titled
md: fix an incorrect NULL check in does_sb_need_changing
to the 5.18-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
md-fix-an-incorrect-null-check-in-does_sb_need_changing.patch
and it can be found in the queue-5.18 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From fc8738343eefc4ea8afb6122826dea48eacde514 Mon Sep 17 00:00:00 2001
From: Xiaomeng Tong <xiam0nd.tong@xxxxxxxxx>
Date: Fri, 8 Apr 2022 16:37:28 +0800
Subject: md: fix an incorrect NULL check in does_sb_need_changing
From: Xiaomeng Tong <xiam0nd.tong@xxxxxxxxx>
commit fc8738343eefc4ea8afb6122826dea48eacde514 upstream.
The bug is here:
if (!rdev)
The list iterator value 'rdev' will *always* be set and non-NULL
by rdev_for_each(), so it is incorrect to assume that the iterator
value will be NULL if the list is empty or no element found.
Otherwise it will bypass the NULL check and lead to invalid memory
access passing the check.
To fix the bug, use a new variable 'iter' as the list iterator,
while using the original variable 'rdev' as a dedicated pointer to
point to the found element.
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 2aa82191ac36 ("md-cluster: Perform a lazy update")
Acked-by: Guoqing Jiang <guoqing.jiang@xxxxxxxxx>
Signed-off-by: Xiaomeng Tong <xiam0nd.tong@xxxxxxxxx>
Acked-by: Goldwyn Rodrigues <rgoldwyn@xxxxxxxx>
Signed-off-by: Song Liu <song@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/md/md.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -2627,14 +2627,16 @@ static void sync_sbs(struct mddev *mddev
static bool does_sb_need_changing(struct mddev *mddev)
{
- struct md_rdev *rdev;
+ struct md_rdev *rdev = NULL, *iter;
struct mdp_superblock_1 *sb;
int role;
/* Find a good rdev */
- rdev_for_each(rdev, mddev)
- if ((rdev->raid_disk >= 0) && !test_bit(Faulty, &rdev->flags))
+ rdev_for_each(iter, mddev)
+ if ((iter->raid_disk >= 0) && !test_bit(Faulty, &iter->flags)) {
+ rdev = iter;
break;
+ }
/* No good device found. */
if (!rdev)
Patches currently in stable-queue which might be from xiam0nd.tong@xxxxxxxxx are
queue-5.18/md-fix-an-incorrect-null-check-in-does_sb_need_changing.patch
queue-5.18/scsi-dc395x-fix-a-missing-check-on-list-iterator.patch
queue-5.18/drm-nouveau-clk-fix-an-incorrect-null-check-on-list-iterator.patch
queue-5.18/media-uvcvideo-fix-missing-check-to-determine-if-ele.patch
queue-5.18/md-fix-an-incorrect-null-check-in-md_reload_sb.patch
queue-5.18/drm-nouveau-kms-nv50-atom-fix-an-incorrect-null-check-on-list-iterator.patch
