[PATCH] permission checks for chdir need special treatment only on the last step

... so we ought to pass MAY_CHDIR to vfs_permission() instead of having
it triggered on every step of preceding pathname resolution.  LOOKUP_CHDIR
is killed by that.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/namei.c

@@ -268,8 +268,6 @@ int permission(struct inode *inode, int mask, struct nameidata *nd)
 		if (nd) {
 			if (nd->flags & LOOKUP_ACCESS)
 				extra |= MAY_ACCESS;
-			if (nd->flags & LOOKUP_CHDIR)
-				extra |= MAY_CHDIR;
 			if (nd->flags & LOOKUP_OPEN)
 				extra |= MAY_OPEN;
 		}