From ec4ab9d2fc08132113dc5d45ac68af2158377122 Mon Sep 17 00:00:00 2001 From: Dan Robertson Date: Wed, 12 May 2021 14:07:57 -0400 Subject: [PATCH] bcachefs: Fix possible null deref on mount Ensure that the block device pointer in a superblock handle is not null before dereferencing it in bch2_dev_to_fs. The block device pointer may be null when mounting a new bcachefs filesystem given another mounted bcachefs filesystem exists that has at least one device that is offline. Signed-off-by: Dan Robertson Signed-off-by: Kent Overstreet --- fs/bcachefs/super.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/bcachefs/super.c b/fs/bcachefs/super.c index 9065e264c5675..71493b5ff6951 100644 --- a/fs/bcachefs/super.c +++ b/fs/bcachefs/super.c @@ -117,7 +117,7 @@ struct bch_fs *bch2_dev_to_fs(dev_t dev) list_for_each_entry(c, &bch_fs_list, list) for_each_member_device_rcu(ca, c, i, NULL) - if (ca->disk_sb.bdev->bd_dev == dev) { + if (ca->disk_sb.bdev && ca->disk_sb.bdev->bd_dev == dev) { closure_get(&c->cl); goto found; } -- 2.30.2