From: Patrick McHardy <kaber@trash.net>
Date: Tue, 5 Jun 2007 12:14:22 +0000 (+0200)
Subject: [UBUNTU] CVE-2007-2876 NETFILTER: {ip, nf}_conntrack_sctp: fix remotely triggerable ...
X-Git-Url: http://kernel.ubuntu.com/git?p=ubuntu/ubuntu-edgy.git;a=commitdiff;h=3ccb814b91bca2e0a6fe4b5d1c5dbb35a06a848b

[UBUNTU] CVE-2007-2876 NETFILTER: {ip, nf}_conntrack_sctp: fix remotely triggerable NULL ptr dereference

When creating a new connection by sending an unknown chunk type, we
don't transition to a valid state, causing a NULL pointer dereference in
sctp_packet when accessing sctp_timeouts[SCTP_CONNTRACK_NONE].

Fix by don't creating new conntrack entry if initial state is invalid.

Noticed by Vilmos Nebehaj <vilmos.nebehaj@ramsys.hu>

CC: Kiran Kumar Immidi <immidi_kiran@yahoo.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>

modified:   net/ipv4/netfilter/ip_conntrack_proto_sctp.c
modified:   net/netfilter/nf_conntrack_proto_sctp.c
---

--- a/net/ipv4/netfilter/ip_conntrack_proto_sctp.c
+++ b/net/ipv4/netfilter/ip_conntrack_proto_sctp.c
@@ -461,7 +461,8 @@ static int sctp_new(struct ip_conntrack 
 						SCTP_CONNTRACK_NONE, sch->type);
 
 		/* Invalid: delete conntrack */
-		if (newconntrack == SCTP_CONNTRACK_MAX) {
+		if (newconntrack == SCTP_CONNTRACK_NONE ||
+		    newconntrack == SCTP_CONNTRACK_MAX) {
 			DEBUGP("ip_conntrack_sctp: invalid new deleting.\n");
 			return 0;
 		}
--- a/net/netfilter/nf_conntrack_proto_sctp.c
+++ b/net/netfilter/nf_conntrack_proto_sctp.c
@@ -467,7 +467,8 @@ static int sctp_new(struct nf_conn *conn
 					 SCTP_CONNTRACK_NONE, sch->type);
 
 		/* Invalid: delete conntrack */
-		if (newconntrack == SCTP_CONNTRACK_MAX) {
+		if (newconntrack == SCTP_CONNTRACK_NONE ||
+		    newconntrack == SCTP_CONNTRACK_MAX) {
 			DEBUGP("nf_conntrack_sctp: invalid new deleting.\n");
 			return 0;
 		}