From: Joel Becker <joel.becker@oracle.com>
Date: Fri, 23 Apr 2010 22:24:59 +0000 (-0700)
Subject: ocfs2_dlmfs: Fix math error when reading LVB.
X-Git-Tag: v2.6.33.4~84
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=fc535314b6f4dc8b400e0bd46bbb42d974d0ff06;p=karo-tx-linux.git

ocfs2_dlmfs: Fix math error when reading LVB.

commit a36d515c7a2dfacebcf41729f6812dbc424ebcf0 upstream.

When asked for a partial read of the LVB in a dlmfs file, we can
accidentally calculate a negative count.

Reported-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/fs/ocfs2/dlm/dlmfs.c b/fs/ocfs2/dlm/dlmfs.c
index 02bf17808bdc..18bc101d603f 100644
--- a/fs/ocfs2/dlm/dlmfs.c
+++ b/fs/ocfs2/dlm/dlmfs.c
@@ -205,7 +205,7 @@ static ssize_t dlmfs_file_read(struct file *filp,
 	if ((count + *ppos) > i_size_read(inode))
 		readlen = i_size_read(inode) - *ppos;
 	else
-		readlen = count - *ppos;
+		readlen = count;
 
 	lvb_buf = kmalloc(readlen, GFP_NOFS);
 	if (!lvb_buf)