lkml.org 
[lkml]   [2012]   [Sep]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[ 45/46] dccp: check ccid before dereferencing
Date
From: Greg KH <gregkh@linuxfoundation.org>

3.0-stable review patch. If anyone has any objections, please let me know.

------------------

From: Mathias Krause <minipli@googlemail.com>

commit 276bdb82dedb290511467a5a4fdbe9f0b52dce6f upstream.

ccid_hc_rx_getsockopt() and ccid_hc_tx_getsockopt() might be called with
a NULL ccid pointer leading to a NULL pointer dereference. This could
lead to a privilege escalation if the attacker is able to map page 0 and
prepare it with a fake ccid_ops pointer.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
net/dccp/ccid.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/net/dccp/ccid.h
+++ b/net/dccp/ccid.h
@@ -246,7 +246,7 @@ static inline int ccid_hc_rx_getsockopt(
u32 __user *optval, int __user *optlen)
{
int rc = -ENOPROTOOPT;
- if (ccid->ccid_ops->ccid_hc_rx_getsockopt != NULL)
+ if (ccid != NULL && ccid->ccid_ops->ccid_hc_rx_getsockopt != NULL)
rc = ccid->ccid_ops->ccid_hc_rx_getsockopt(sk, optname, len,
optval, optlen);
return rc;
@@ -257,7 +257,7 @@ static inline int ccid_hc_tx_getsockopt(
u32 __user *optval, int __user *optlen)
{
int rc = -ENOPROTOOPT;
- if (ccid->ccid_ops->ccid_hc_tx_getsockopt != NULL)
+ if (ccid != NULL && ccid->ccid_ops->ccid_hc_tx_getsockopt != NULL)
rc = ccid->ccid_ops->ccid_hc_tx_getsockopt(sk, optname, len,
optval, optlen);
return rc;



\
 
 \ /
  Last update: 2012-09-13 06:01    [W:0.222 / U:0.056 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site