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 48a066e72d ("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
This commit is contained in:
Linus Torvalds 2013-11-29 09:27:19 -08:00
commit b01537bfbc

View file

@ -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;
}
/*