4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Zhang Shurong <zhang_shurong@xxxxxxxxxxx> [ 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@xxxxxxxxxxx> Reviewed-by: Yu Kuai <yukuai3@xxxxxxxxxx> Link: https://lore.kernel.org/r/tencent_0D24426FAC6A21B69AC0C03CE4143A508F09@xxxxxx Signed-off-by: Song Liu <song@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/md/raid1.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index 0f8b1fb3d0517..b459a3af94224 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -1783,6 +1783,10 @@ 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) -- 2.40.1