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>
---
drivers/md/raid1.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index dd25832eb045..3e294dc408fa 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -1829,6 +1829,10 @@ 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 >= mddev->raid_disks))
+ goto abort;
+
struct raid1_info *p = conf->mirrors + number;
if (rdev != p->rdev)
--
2.30.2
