[PATCH v5 5/5] ceph: prevent snapshots to be created in encrypted locked directories

["Luís Henriques" <lhenriques@suse.de>]

With snapshot names encryption we can not allow snapshots to be created in
locked directories because the names wouldn't be encrypted.  This patch
forces the directory to be unlocked to allow a snapshot to be created.

Signed-off-by: Luís Henriques <lhenriques@suse.de>
---
 fs/ceph/dir.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c
index f48f1ff20927..44b7114ca267 100644
--- a/fs/ceph/dir.c
+++ b/fs/ceph/dir.c
@@ -1071,6 +1071,11 @@ static int ceph_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
 		err = -EDQUOT;
 		goto out;
 	}
+	if ((op == CEPH_MDS_OP_MKSNAP) && IS_ENCRYPTED(dir) &&
+	    !fscrypt_has_encryption_key(dir)) {
+		err = -ENOKEY;
+		goto out;
+	}
 
 
 	req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);