1 files changed, 18 insertions, 29 deletions

diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index 746ea36f3171..b368e2e102fa 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -1,10 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  *
  * Copyright (C) 2011 Novell Inc.
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 as published by
- * the Free Software Foundation.
  */
 
 #include <uapi/linux/magic.h>
@@ -31,29 +28,29 @@ struct ovl_dir_cache;
 
 static bool ovl_redirect_dir_def = IS_ENABLED(CONFIG_OVERLAY_FS_REDIRECT_DIR);
 module_param_named(redirect_dir, ovl_redirect_dir_def, bool, 0644);
-MODULE_PARM_DESC(ovl_redirect_dir_def,
+MODULE_PARM_DESC(redirect_dir,
 		 "Default to on or off for the redirect_dir feature");
 
 static bool ovl_redirect_always_follow =
 	IS_ENABLED(CONFIG_OVERLAY_FS_REDIRECT_ALWAYS_FOLLOW);
 module_param_named(redirect_always_follow, ovl_redirect_always_follow,
 		   bool, 0644);
-MODULE_PARM_DESC(ovl_redirect_always_follow,
+MODULE_PARM_DESC(redirect_always_follow,
 		 "Follow redirects even if redirect_dir feature is turned off");
 
 static bool ovl_index_def = IS_ENABLED(CONFIG_OVERLAY_FS_INDEX);
 module_param_named(index, ovl_index_def, bool, 0644);
-MODULE_PARM_DESC(ovl_index_def,
+MODULE_PARM_DESC(index,
 		 "Default to on or off for the inodes index feature");
 
 static bool ovl_nfs_export_def = IS_ENABLED(CONFIG_OVERLAY_FS_NFS_EXPORT);
 module_param_named(nfs_export, ovl_nfs_export_def, bool, 0644);
-MODULE_PARM_DESC(ovl_nfs_export_def,
+MODULE_PARM_DESC(nfs_export,
 		 "Default to on or off for the NFS export feature");
 
 static bool ovl_xino_auto_def = IS_ENABLED(CONFIG_OVERLAY_FS_XINO_AUTO);
 module_param_named(xino_auto, ovl_xino_auto_def, bool, 0644);
-MODULE_PARM_DESC(ovl_xino_auto_def,
+MODULE_PARM_DESC(xino_auto,
 		 "Auto enable xino feature");
 
 static void ovl_entry_stack_free(struct ovl_entry *oe)
@@ -66,7 +63,7 @@ static void ovl_entry_stack_free(struct ovl_entry *oe)
 
 static bool ovl_metacopy_def = IS_ENABLED(CONFIG_OVERLAY_FS_METACOPY);
 module_param_named(metacopy, ovl_metacopy_def, bool, 0644);
-MODULE_PARM_DESC(ovl_metacopy_def,
+MODULE_PARM_DESC(metacopy,
 		 "Default to on or off for the metadata only copy up feature");
 
 static void ovl_dentry_release(struct dentry *dentry)
@@ -995,8 +992,8 @@ static int ovl_setup_trap(struct super_block *sb, struct dentry *dir,
 	int err;
 
 	trap = ovl_get_trap_inode(sb, dir);
-	err = PTR_ERR(trap);
-	if (IS_ERR(trap)) {
+	err = PTR_ERR_OR_ZERO(trap);
+	if (err) {
 		if (err == -ELOOP)
 			pr_err("overlayfs: conflicting %s path\n", name);
 		return err;
@@ -1471,23 +1468,20 @@ out_err:
  * Check if this layer root is a descendant of:
  * - another layer of this overlayfs instance
  * - upper/work dir of any overlayfs instance
- * - a disconnected dentry (detached root)
  */
 static int ovl_check_layer(struct super_block *sb, struct dentry *dentry,
 			   const char *name)
 {
-	struct dentry *next, *parent;
-	bool is_root = false;
+	struct dentry *next = dentry, *parent;
 	int err = 0;
 
-	if (!dentry || dentry == dentry->d_sb->s_root)
+	if (!dentry)
 		return 0;
 
-	next = dget(dentry);
-	/* Walk back ancestors to fs root (inclusive) looking for traps */
-	do {
-		parent = dget_parent(next);
-		is_root = (parent == next);
+	parent = dget_parent(next);
+
+	/* Walk back ancestors to root (inclusive) looking for traps */
+	while (!err && parent != next) {
 		if (ovl_is_inuse(parent)) {
 			err = -EBUSY;
 			pr_err("overlayfs: %s path overlapping in-use upperdir/workdir\n",
@@ -1496,17 +1490,12 @@ static int ovl_check_layer(struct super_block *sb, struct dentry *dentry,
 			err = -ELOOP;
 			pr_err("overlayfs: overlapping %s path\n", name);
 		}
-		dput(next);
 		next = parent;
-	} while (!err && !is_root);
-
-	/* Did we really walk to fs root or found a detached root? */
-	if (!err && next != dentry->d_sb->s_root) {
-		err = -ESTALE;
-		pr_err("overlayfs: disconnected %s path\n", name);
+		parent = dget_parent(next);
+		dput(next);
 	}
 
-	dput(next);
+	dput(parent);
 
 	return err;
 }