userns: Convert user specfied uids and gids in chown into kuids and kgid

Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>

diff --git a/fs/open.c b/fs/open.c
index 92335f6635452ed7f8b0b21252d88762771fb33b..e166801383238f948c2c2218a175be4ec0887c52 100644 (file)
--- a/fs/open.c
+++ b/fs/open.c
@@ -506,15 +506,24 @@ static int chown_common(struct path *path, uid_t user, gid_t group)
        struct inode *inode = path->dentry->d_inode;
        int error;
        struct iattr newattrs;
+       kuid_t uid;
+       kgid_t gid;
+
+       uid = make_kuid(current_user_ns(), user);
+       gid = make_kgid(current_user_ns(), group);
 
        newattrs.ia_valid =  ATTR_CTIME;
        if (user != (uid_t) -1) {
+               if (!uid_valid(uid))
+                       return -EINVAL;
                newattrs.ia_valid |= ATTR_UID;
-               newattrs.ia_uid = user;
+               newattrs.ia_uid = uid;
        }
        if (group != (gid_t) -1) {
+               if (!gid_valid(gid))
+                       return -EINVAL;
                newattrs.ia_valid |= ATTR_GID;
-               newattrs.ia_gid = group;
+               newattrs.ia_gid = gid;
        }
        if (!S_ISDIR(inode->i_mode))
                newattrs.ia_valid |=