[RFC v7 34/41] ext4: Don't allow unmapped identifiers in richacls

[Andreas Gruenbacher <agruenba@redhat.com>]

Don't allow acls which contain unmapped identifiers: they are meaningful
for remote file systems only.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
---
 fs/ext4/richacl.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/fs/ext4/richacl.c b/fs/ext4/richacl.c
index 6758def..ca6e0cb 100644
--- a/fs/ext4/richacl.c
+++ b/fs/ext4/richacl.c
@@ -68,8 +68,13 @@ ext4_set_richacl(handle_t *handle, struct inode *inode, struct richacl *acl)
 	int retval;
 
 	if (acl) {
-		mode_t mode = inode->i_mode;
+		mode_t mode;
 
+		/* Don't allow acls with unmapped identifiers. */
+		if (richacl_has_unmapped_identifiers(acl))
+			return -EINVAL;
+
+		mode = inode->i_mode;
 		if (richacl_equiv_mode(acl, &mode) == 0) {
 			inode->i_mode = mode;
 			ext4_mark_inode_dirty(handle, inode);
-- 
2.4.3