From: Greg KH on
2.6.32-stable review patch. If anyone has any objections, please let us know.

------------------

From: TARUISI Hiroaki <taruishi.hiroak(a)jp.fujitsu.com>

commit 4a8be425a8fb8fbb5d881eb55fa6634c3463b9c9 upstream.

I rebased Christian Parpart's patch to deny hard link across
subvolumes. Original patch modifies also btrfs_rename, but
I excluded it because we can move across subvolumes now and
it make no problem.
-----------------

Hard link across subvolumes should not allowed in Btrfs.
btrfs_link checks root of 'to' directory is same as root
of 'from' file. If not same, btrfs_link returns -EPERM.

Signed-off-by: TARUISI Hiroaki <taruishi.hiroak(a)jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason(a)oracle.com>
Acked-by: Jeff Mahoney <jeffm(a)suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)suse.de>


---
fs/btrfs/inode.c | 4 ++++
1 file changed, 4 insertions(+)

--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -4462,6 +4462,10 @@ static int btrfs_link(struct dentry *old
if (inode->i_nlink == 0)
return -ENOENT;

+ /* do not allow sys_link's with other subvols of the same device */
+ if (root->objectid != BTRFS_I(inode)->root->objectid)
+ return -EPERM;
+
/*
* 1 item for inode ref
* 2 items for dir items


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo(a)vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/