Commit 3ca30d40 authored Jul 25, 2011 by Pavel Shilovsky Committed by Al Viro Jul 25, 2011

CIFS: Fix oops while mounting with prefixpath



commit fec11dd9 caused
a regression when we have already mounted //server/share/a
and want to mount //server/share/a/b.

The problem is that lookup_one_len calls __lookup_hash
with nd pointer as NULL. Then __lookup_hash calls
do_revalidate in the case when dentry exists and we end
up with NULL pointer deference in cifs_d_revalidate:

if (nd->flags & LOOKUP_RCU)
	return -ECHILD;

Fix this by checking nd for NULL.

Signed-off-by: Pavel Shilovsky <piastryyy@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

parent 340a0a01

fs/cifs/dir.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -641,7 +641,7 @@ lookup_out:
		static int
		cifs_d_revalidate(struct dentry direntry, struct nameidata nd)
		{
		if (nd->flags & LOOKUP_RCU)
		if (nd && (nd->flags & LOOKUP_RCU))
		return -ECHILD;

		if (direntry->d_inode) {

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