- use xz patch source

[packages/kernel.git] / ovl12-ovl-switch-to-__inode_permission.patch

From 8b0d519c119a64887df868e7f821e8a714da3d71 Mon Sep 17 00:00:00 2001
From: Andy Whitcroft <apw@canonical.com>
Date: Tue, 1 May 2012 16:17:52 +0100
Subject: [PATCH 12/13] ovl: switch to __inode_permission()
Patch-mainline: not yet

When checking permissions on an overlayfs inode we do not take into
account either device cgroup restrictions nor security permissions.
This allows a user to mount an overlayfs layer over a restricted device
directory and by pass those permissions to open otherwise restricted
files.

Switch over to __inode_permissions.

Signed-off-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
---
 fs/overlayfs/inode.c |   12 +-----------
 1 file changed, 1 insertion(+), 11 deletions(-)

Index: linux-3.6-rc7-master/fs/overlayfs/inode.c
===================================================================
--- linux-3.6-rc7-master.orig/fs/overlayfs/inode.c	2012-09-28 13:37:02.000000000 +0200
+++ linux-3.6-rc7-master/fs/overlayfs/inode.c	2012-09-28 13:37:08.000000000 +0200
@@ -100,19 +100,9 @@ int ovl_permission(struct inode *inode,
 		if (is_upper && !IS_RDONLY(inode) && IS_RDONLY(realinode) &&
 		    (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)))
 			goto out_dput;
-
-		/*
-		 * Nobody gets write access to an immutable file.
-		 */
-		err = -EACCES;
-		if (IS_IMMUTABLE(realinode))
-			goto out_dput;
 	}
 
-	if (realinode->i_op->permission)
-		err = realinode->i_op->permission(realinode, mask);
-	else
-		err = generic_permission(realinode, mask);
+	err = __inode_permission(realinode, mask);
 out_dput:
 	dput(alias);
 	return err;