2.6.32-longterm review patch.  If anyone has any objections, please let me know.

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

From: Mathias Krause <mini...@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 <mini...@googlemail.com>
Cc: Gerrit Renker <ger...@erg.abdn.ac.uk>
Signed-off-by: David S. Miller <da...@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
Signed-off-by: Willy Tarreau <w...@1wt.eu>
---
 net/dccp/ccid.h |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/dccp/ccid.h b/net/dccp/ccid.h
index facedd2..ab260b0 100644
--- a/net/dccp/ccid.h
+++ b/net/dccp/ccid.h
@@ -214,7 +214,7 @@ static inline int ccid_hc_rx_getsockopt(struct ccid *ccid, 
struct sock *sk,
                                        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;
@@ -225,7 +225,7 @@ static inline int ccid_hc_tx_getsockopt(struct ccid *ccid, 
struct sock *sk,
                                        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;
-- 
1.7.2.1.45.g54fbc



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