From d7a4783883d350e33308bf7c9ef0fe4e38f9c8e2 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 1 Feb 2021 14:17:20 +0100 Subject: [PATCH] md: check for NULL ->meta_bdev before calling bdev_read_only ->meta_bdev is optional and not set for most arrays. Add a rdev_read_only helper that calls bdev_read_only for both devices in a safe way. Fixes: 6f0d9689b670 ("block: remove the NULL bdev check in bdev_read_only") Reported-by: Guoqing Jiang Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- drivers/md/md.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/drivers/md/md.c b/drivers/md/md.c index 399c81bddc1a..7c0f61078653 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -2399,6 +2399,12 @@ int md_integrity_add_rdev(struct md_rdev *rdev, struct mddev *mddev) } EXPORT_SYMBOL(md_integrity_add_rdev); +static bool rdev_read_only(struct md_rdev *rdev) +{ + return bdev_read_only(rdev->bdev) || + (rdev->meta_bdev && bdev_read_only(rdev->meta_bdev)); +} + static int bind_rdev_to_array(struct md_rdev *rdev, struct mddev *mddev) { char b[BDEVNAME_SIZE]; @@ -2408,8 +2414,7 @@ static int bind_rdev_to_array(struct md_rdev *rdev, struct mddev *mddev) if (find_rdev(mddev, rdev->bdev->bd_dev)) return -EEXIST; - if ((bdev_read_only(rdev->bdev) || bdev_read_only(rdev->meta_bdev)) && - mddev->pers) + if (rdev_read_only(rdev) && mddev->pers) return -EROFS; /* make sure rdev->sectors exceeds mddev->dev_sectors */ @@ -5843,9 +5848,7 @@ int md_run(struct mddev *mddev) continue; sync_blockdev(rdev->bdev); invalidate_bdev(rdev->bdev); - if (mddev->ro != 1 && - (bdev_read_only(rdev->bdev) || - bdev_read_only(rdev->meta_bdev))) { + if (mddev->ro != 1 && rdev_read_only(rdev)) { mddev->ro = 1; if (mddev->gendisk) set_disk_ro(mddev->gendisk, 1);