lkml.org 
[lkml]   [2011]   [Oct]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[24/27] x25: Prevent skb overreads when checking call user data
3.0-stable review patch.  If anyone has any objections, please let us know.

------------------
From: Matthew Daley <mattjd@gmail.com>

commit 7f81e25befdfb3272345a2e775f520e1d515fa20 upstream.

x25_find_listener does not check that the amount of call user data given
in the skb is big enough in per-socket comparisons, hence buffer
overreads may occur. Fix this by adding a check.

Signed-off-by: Matthew Daley <mattjd@gmail.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Andrew Hendry <andrew.hendry@gmail.com>
Acked-by: Andrew Hendry <andrew.hendry@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
net/x25/af_x25.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/net/x25/af_x25.c
+++ b/net/x25/af_x25.c
@@ -295,7 +295,8 @@ static struct sock *x25_find_listener(st
* Found a listening socket, now check the incoming
* call user data vs this sockets call user data
*/
- if(skb->len > 0 && x25_sk(s)->cudmatchlength > 0) {
+ if (x25_sk(s)->cudmatchlength > 0 &&
+ skb->len >= x25_sk(s)->cudmatchlength) {
if((memcmp(x25_sk(s)->calluserdata.cuddata,
skb->data,
x25_sk(s)->cudmatchlength)) == 0) {



\
 
 \ /
  Last update: 2011-10-23 08:37    [from the cache]
©2003-2011 Jasper Spaans