From 4a8be425a8fb8fbb5d881eb55fa6634c3463b9c9 Mon Sep 17 00:00:00 2001 From: TARUISI Hiroaki Date: Thu, 12 Nov 2009 07:14:26 +0000 Subject: [PATCH] Btrfs: deny sys_link across subvolumes. 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 Signed-off-by: Chris Mason --- fs/btrfs/inode.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 168e8c040aab..da76cad92ecf 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -4462,6 +4462,10 @@ static int btrfs_link(struct dentry *old_dentry, struct inode *dir, 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 -- 2.20.1