From: Christoph Hellwig <hch@lst.de>
Date: Thu, 12 Feb 2009 18:56:00 +0000 (+0100)
Subject: xfs: reject swapext ioctl on swapfiles
X-Git-Tag: v2.6.30-rc1~232^2~21^2
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=7c8f7af67de19a7ae33a6fc06764771265b0cc56;p=karo-tx-linux.git

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 ac96ab9f70a2..e6d839bddbf0 100644
--- a/fs/xfs/xfs_dfrag.c
+++ b/fs/xfs/xfs_dfrag.c
@@ -79,6 +79,12 @@ xfs_swapext(
 		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);