userns: Convert s390 hypfs to use kuid and kgid where appropriate

Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
diff --git a/arch/s390/hypfs/inode.c b/arch/s390/hypfs/inode.c
index 6767b43..124ec1a 100644
--- a/arch/s390/hypfs/inode.c
+++ b/arch/s390/hypfs/inode.c
@@ -31,8 +31,8 @@
 					       struct dentry *dir);
 
 struct hypfs_sb_info {
-	uid_t uid;			/* uid used for files and dirs */
-	gid_t gid;			/* gid used for files and dirs */
+	kuid_t uid;			/* uid used for files and dirs */
+	kgid_t gid;			/* gid used for files and dirs */
 	struct dentry *update_file;	/* file to trigger update */
 	time_t last_update;		/* last update time in secs since 1970 */
 	struct mutex lock;		/* lock to protect update process */
@@ -229,6 +229,8 @@
 {
 	char *str;
 	substring_t args[MAX_OPT_ARGS];
+	kuid_t uid;
+	kgid_t gid;
 
 	if (!options)
 		return 0;
@@ -243,12 +245,18 @@
 		case opt_uid:
 			if (match_int(&args[0], &option))
 				return -EINVAL;
-			hypfs_info->uid = option;
+			uid = make_kuid(current_user_ns(), option);
+			if (!uid_valid(uid))
+				return -EINVAL;
+			hypfs_info->uid = uid;
 			break;
 		case opt_gid:
 			if (match_int(&args[0], &option))
 				return -EINVAL;
-			hypfs_info->gid = option;
+			gid = make_kgid(current_user_ns(), option);
+			if (!gid_valid(gid))
+				return -EINVAL;
+			hypfs_info->gid = gid;
 			break;
 		case opt_err:
 		default:
@@ -263,8 +271,8 @@
 {
 	struct hypfs_sb_info *hypfs_info = root->d_sb->s_fs_info;
 
-	seq_printf(s, ",uid=%u", hypfs_info->uid);
-	seq_printf(s, ",gid=%u", hypfs_info->gid);
+	seq_printf(s, ",uid=%u", from_kuid_munged(&init_user_ns, hypfs_info->uid));
+	seq_printf(s, ",gid=%u", from_kgid_munged(&init_user_ns, hypfs_info->gid));
 	return 0;
 }