path_connected(): pass mount and dentry separately (6b03f7ed) · Commits · 戴 / test

fs/namei.c

+5 −7

Original line number	Diff line number	Diff line
		@@ -550,22 +550,20 @@ static int __nd_alloc_stack(struct nameidata *nd)
		}

		/**
		* path_connected - Verify that a path->dentry is below path->mnt.mnt_root
		* @path: nameidate to verify
		* path_connected - Verify that a dentry is below mnt.mnt_root
		*
		* Rename can sometimes move a file or directory outside of a bind
		* mount, path_connected allows those cases to be detected.
		*/
		static bool path_connected(const struct path *path)
		static bool path_connected(struct vfsmount mnt, struct dentry dentry)
		{
		struct vfsmount *mnt = path->mnt;
		struct super_block *sb = mnt->mnt_sb;

		/* Bind mounts and multi-root filesystems can have disconnected paths */
		if (!(sb->s_iflags & SB_I_MULTIROOT) && (mnt->mnt_root == sb->s_root))
		return true;

		return is_subdir(path->dentry, mnt->mnt_root);
		return is_subdir(dentry, mnt->mnt_root);
		}

		static inline int nd_alloc_stack(struct nameidata *nd)
		@@ -1386,7 +1384,7 @@ static int follow_dotdot_rcu(struct nameidata *nd)
		return -ECHILD;
		nd->path.dentry = parent;
		nd->seq = seq;
		if (unlikely(!path_connected(&nd->path)))
		if (unlikely(!path_connected(nd->path.mnt, parent)))
		return -ECHILD;
		break;
		} else {
		@@ -1448,7 +1446,7 @@ static int path_parent_directory(struct path *path)
		/* rare case of legitimate dget_parent()... */
		path->dentry = dget_parent(path->dentry);
		dput(old);
		if (unlikely(!path_connected(path)))
		if (unlikely(!path_connected(path->mnt, path->dentry)))
		return -ENOENT;
		return 0;
		}