Commit b01537bf authored Nov 29, 2013 by Linus Torvalds

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull vfs dentry reference count fix from Al Viro.

This fixes a possible inode_permission NULL pointer dereference (and
other problems) that were due to the root dentry count being decremented
too much.  In commit 48a066e7 ("RCU'd vfsmounts") the placement of
clearing the LOOKUP_RCU bit changed, and we then returned failure of
incrementing the lockref on the parent dentry with LOOKUP_RCU cleared.

But that meant we needed to go through the same cleanup routines that
the later failures did wrt LOOKUP_ROOT and nd->root.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fix bogus path_put() of nd->root after some unlazy_walk() failures

parents 282c183b d870b4a1

fs/namei.c

+1 −2

Original line number	Diff line number	Diff line
		@@ -513,8 +513,7 @@ static int unlazy_walk(struct nameidata nd, struct dentry dentry)

		if (!lockref_get_not_dead(&parent->d_lockref)) {
		nd->path.dentry = NULL;
		rcu_read_unlock();
		return -ECHILD;
		goto out;
		}

		/*