1 From 8b0d519c119a64887df868e7f821e8a714da3d71 Mon Sep 17 00:00:00 2001
2 From: Andy Whitcroft <apw@canonical.com>
3 Date: Tue, 1 May 2012 16:17:52 +0100
4 Subject: [PATCH 12/13] ovl: switch to __inode_permission()
5 Patch-mainline: not yet
7 When checking permissions on an overlayfs inode we do not take into
8 account either device cgroup restrictions nor security permissions.
9 This allows a user to mount an overlayfs layer over a restricted device
10 directory and by pass those permissions to open otherwise restricted
13 Switch over to __inode_permissions.
15 Signed-off-by: Andy Whitcroft <apw@canonical.com>
16 Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
18 fs/overlayfs/inode.c | 12 +-----------
19 1 file changed, 1 insertion(+), 11 deletions(-)
21 Index: linux-3.6-rc7-master/fs/overlayfs/inode.c
22 ===================================================================
23 --- linux-3.6-rc7-master.orig/fs/overlayfs/inode.c 2012-09-28 13:37:02.000000000 +0200
24 +++ linux-3.6-rc7-master/fs/overlayfs/inode.c 2012-09-28 13:37:08.000000000 +0200
25 @@ -100,19 +100,9 @@ int ovl_permission(struct inode *inode,
26 if (is_upper && !IS_RDONLY(inode) && IS_RDONLY(realinode) &&
27 (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)))
31 - * Nobody gets write access to an immutable file.
34 - if (IS_IMMUTABLE(realinode))
38 - if (realinode->i_op->permission)
39 - err = realinode->i_op->permission(realinode, mask);
41 - err = generic_permission(realinode, mask);
42 + err = __inode_permission(realinode, mask);