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
