[PATCH] mm/hugetlbfs: fix error handling when setting up mounts

[Mike Kravetz]

It is assumed that the hugetlbfs_vfsmount[] array will contain
either a valid vfsmount pointer or NULL for each hstate after
initialization.  Changes made while converting to use fs_context
broke this assumption.

Reported-by: Chengguang Xu <cgxu519@xxxxxxxxxxxx>
Fixes: 32021982a324 ("hugetlbfs: Convert to fs_context")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
---
 fs/hugetlbfs/inode.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index a478df035651..178389209561 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -1470,15 +1470,17 @@ static int __init init_hugetlbfs_fs(void)
 	i = 0;
 	for_each_hstate(h) {
 		mnt = mount_one_hugetlbfs(h);
-		if (IS_ERR(mnt) && i == 0) {
+		if (IS_ERR(mnt)) {
+			hugetlbfs_vfsmount[i] = NULL;
 			error = PTR_ERR(mnt);
-			goto out;
+		} else {
+			hugetlbfs_vfsmount[i] = mnt;
 		}
-		hugetlbfs_vfsmount[i] = mnt;
 		i++;
 	}
 
-	return 0;
+	if (hugetlbfs_vfsmount[default_hstate_idx] != NULL)
+		return 0;
 
  out:
 	kmem_cache_destroy(hugetlbfs_inode_cachep);
-- 
2.20.1