xfs: reject swapext ioctl on swapfiles
Swapfiles are magic - I/O is directly initialized by the VM without
involving the filesystem. Swapping out extents underneath the VM thus
can cause severe problems.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Felix Blyakher <felixb@sgi.com>
diff --git a/fs/xfs/xfs_dfrag.c b/fs/xfs/xfs_dfrag.c
index ac96ab9..e6d839b 100644
--- a/fs/xfs/xfs_dfrag.c
+++ b/fs/xfs/xfs_dfrag.c
@@ -79,6 +79,12 @@
goto out_put_target_file;
}
+ if (IS_SWAPFILE(file->f_path.dentry->d_inode) ||
+ IS_SWAPFILE(target_file->f_path.dentry->d_inode)) {
+ error = XFS_ERROR(EINVAL);
+ goto out_put_target_file;
+ }
+
ip = XFS_I(file->f_path.dentry->d_inode);
tip = XFS_I(target_file->f_path.dentry->d_inode);