Patch "9p: BUG before corrupting memory" has been added to the 3.4-stable tree

Patch "9p: BUG before corrupting memory" has been added to the 3.4-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    9p: BUG before corrupting memory

to the 3.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     9p-bug-before-corrupting-memory.patch
and it can be found in the queue-3.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 5fcb08befaf57faa1b00e514915c1660252b8c26 Mon Sep 17 00:00:00 2001
From: Sasha Levin <levinsasha928@gmail.com>
Date: Mon, 11 Jun 2012 10:18:13 -0500
Subject: 9p: BUG before corrupting memory

From: Sasha Levin <levinsasha928@gmail.com>

commit 5fcb08befaf57faa1b00e514915c1660252b8c26 upstream.

The BUG_ON() in pack_sg_list() would get triggered only one time after we've
corrupted some memory by sg_set_buf() into an invalid sg buffer.

I'm still working on figuring out why I manage to trigger that bug...

Signed-off-by: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 net/9p/trans_virtio.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/net/9p/trans_virtio.c
+++ b/net/9p/trans_virtio.c
@@ -192,10 +192,10 @@ static int pack_sg_list(struct scatterli
 		s = rest_of_page(data);
 		if (s > count)
 			s = count;
+		BUG_ON(index > limit);
 		sg_set_buf(&sg[index++], data, s);
 		count -= s;
 		data += s;
-		BUG_ON(index > limit);
 	}
 
 	return index-start;


Patches currently in stable-queue which might be from levinsasha928@gmail.com are

queue-3.4/9p-bug-before-corrupting-memory.patch