netdev - [PATCH net-next v2 1/4] Fix null pointer dereference in UDP uncompression function

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Fri,  6 Jul 2012 00:50:22 -0400
From:	Tony Cheneau <tony.cheneau@...esiak.org>
To:	"David S. Miller" <davem@...emloft.net>
Cc:	netdev@...r.kernel.org,
	Alexander Smirnov <alex.bluesman.smirnov@...il.com>
Subject: [PATCH net-next v2 1/4] Fix null pointer dereference in UDP uncompression function

When a UDP packet gets fragmented, a crash will occur at reassembly time.
This is because skb->transport_header is not set during earlier period of fragment reassembly.
As a consequence, call to udp_hdr() return NULL and uh (which is NULL) gets
dereferenced without much test.

---
 net/ieee802154/6lowpan.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/net/ieee802154/6lowpan.c b/net/ieee802154/6lowpan.c
index f4070e5..07fa200 100644
--- a/net/ieee802154/6lowpan.c
+++ b/net/ieee802154/6lowpan.c
@@ -314,6 +314,9 @@ lowpan_uncompress_udp_header(struct sk_buff *skb)
 {
 	struct udphdr *uh = udp_hdr(skb);
 	u8 tmp;
+
+	if (!uh)
+		goto err;
 
 	if (lowpan_fetch_skb_u8(skb, &tmp))
 		goto err;
-- 
1.7.3.4

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html