Commit ce9d7f7b authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'CVE-2014-7970' of git://git.kernel.org/pub/scm/linux/kernel/git/luto/linux 

Pull pivot_root() fix from Andy Lutomirski.

Prevent a leak of unreachable mounts.

* 'CVE-2014-7970' of git://git.kernel.org/pub/scm/linux/kernel/git/luto/linux:
  mnt: Prevent pivot_root from creating a loop in the mount tree
parents 2d65a9f4 0d082601

fs/namespace.c

+3 −0
Original line number Diff line number Diff line
@@ -2915,6 +2915,9 @@ SYSCALL_DEFINE2(pivot_root, const char __user *, new_root, 
	/* make sure we can reach put_old from new_root */

	if (!is_path_reachable(old_mnt, old.dentry, &new))

		goto out4;

	/* make certain new is below the root */

	if (!is_path_reachable(new_mnt, new.dentry, &root))

		goto out4;

	root_mp->m_count++; /* pin it so it won't go away */

	lock_mount_hash();

	detach_mnt(new_mnt, &parent_path);