[PATCH 5.7 160/204] md-cluster: Fix potential error pointer dereference in resize_bitmaps()

Greg Kroah-Hartman
2020-08-20T12:53:48Z

From: Dan Carpenter <dan.carpenter@oracle.com>

[ Upstream commit e8abe1de43dac658dacbd04a4543e0c988a8d386 ]

The error handling calls md_bitmap_free(bitmap) which checks for NULL
but will Oops if we pass an error pointer. Let's set "bitmap" to NULL
on this error path.

Fixes: afd756286083 ("md-cluster/raid10: resize all the bitmaps before start reshape")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/md/md-cluster.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/md/md-cluster.c b/drivers/md/md-cluster.c
index 73fd50e779754..d50737ec40394 100644
--- a/drivers/md/md-cluster.c
+++ b/drivers/md/md-cluster.c
@@ -1139,6 +1139,7 @@ static int resize_bitmaps(struct mddev *mddev, sector_t newsize, sector_t oldsiz
bitmap = get_bitmap_from_slot(mddev, i);
if (IS_ERR(bitmap)) {
pr_err("can't get bitmap from slot %d\n", i);
+ bitmap = NULL;
goto out;
}
counts = &bitmap->counts;
--
2.25.1