netdev - v2 [PATCH 6/7] dccp: Fix incorrect length check for ICMPv4 packets

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]

Message-ID: <20080725143033.GC7422@gerrit.erg.abdn.ac.uk>
Date:	Fri, 25 Jul 2008 15:30:33 +0100
From:	Gerrit Renker <gerrit@....abdn.ac.uk>
To:	davem@...emloft.net, dccp@...r.kernel.org, netdev@...r.kernel.org
Subject: v2 [PATCH 6/7] dccp: Fix incorrect length check for ICMPv4 packets

Unlike TCP, which only needs 8 octets of original packet data, DCCP requires
minimally 12 or 16 bytes for ICMP-payload sequence number checks.

This patch replaces the insufficient length constant of 8 with a dynamic
value, using the routine introduced previously.

Signed-off-by: Wei Yongjun <yjwei@...fujitsu.com>
Signed-off-by: Gerrit Renker <gerrit@....abdn.ac.uk>
---
 net/dccp/ipv4.c |    6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)

--- a/net/dccp/ipv4.c
+++ b/net/dccp/ipv4.c
@@ -196,8 +196,8 @@ static inline void dccp_do_pmtu_discovery(struct sock *sk,
 static void dccp_v4_err(struct sk_buff *skb, u32 info)
 {
 	const struct iphdr *iph = (struct iphdr *)skb->data;
-	const struct dccp_hdr *dh = (struct dccp_hdr *)(skb->data +
-							(iph->ihl << 2));
+	const u8 offset = (iph->ihl << 2);
+	const struct dccp_hdr *dh = (struct dccp_hdr *)(skb->data + offset);
 	struct dccp_sock *dp;
 	struct inet_sock *inet;
 	const int type = icmp_hdr(skb)->type;
@@ -207,7 +207,7 @@ static void dccp_v4_err(struct sk_buff *skb, u32 info)
 	int err;
 	struct net *net = dev_net(skb->dev);
 
-	if (skb->len < (iph->ihl << 2) + 8) {
+	if (dccp_skb_too_short(skb, offset)) {
 		ICMP_INC_STATS_BH(net, ICMP_MIB_INERRORS);
 		return;
 	}
--
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