4.14-stable review patch. If anyone has any objections, please let me know.
------------------
From: Zhang Shurong zhang_shurong@foxmail.com
[ Upstream commit 8b0472b50bcf0f19a5119b00a53b63579c8e1e4d ]
If rddev->raid_disk is greater than mddev->raid_disks, there will be an out-of-bounds in raid1_remove_disk(). We have already found similar reports as follows:
1) commit d17f744e883b ("md-raid10: fix KASAN warning") 2) commit 1ebc2cec0b7d ("dm raid: fix KASAN warning in raid5_remove_disk")
Fix this bug by checking whether the "number" variable is valid.
Signed-off-by: Zhang Shurong zhang_shurong@foxmail.com Reviewed-by: Yu Kuai yukuai3@huawei.com Link: https://lore.kernel.org/r/tencent_0D24426FAC6A21B69AC0C03CE4143A508F09@qq.co... Signed-off-by: Song Liu song@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/md/raid1.c | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index 28f78199de3ba..3e54b6639e213 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -1775,6 +1775,10 @@ static int raid1_remove_disk(struct mddev *mddev, struct md_rdev *rdev) struct r1conf *conf = mddev->private; int err = 0; int number = rdev->raid_disk; + + if (unlikely(number >= conf->raid_disks)) + goto abort; + struct raid1_info *p = conf->mirrors + number;
if (rdev != p->rdev)