netdev - Re: [PATCH] icmp: Fixed bug in raw sockets causing incorrect ICMP SNMP counter values

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:	Sun, 11 Oct 2015 16:09:29 -0700
From:	Eric Dumazet <eric.dumazet@...il.com>
To:	Ben Cox <ben@...jojo.co.uk>
Cc:	davem@...emloft.net, netdev@...r.kernel.org,
	linux-kernel@...r.kernel.org, ben+patches@...jojo.co.uk,
	David L Stevens <dlstevens@...ibm.com>
Subject: Re: [PATCH] icmp: Fixed bug in raw sockets causing incorrect ICMP
 SNMP counter values

On Sun, 2015-10-11 at 15:44 -0700, Eric Dumazet wrote:
> On Sun, 2015-10-11 at 15:43 -0700, Eric Dumazet wrote:
> 
> > But your code reads 21th byte.
> 
> BTW, nice catch !

Maybe the following one.

1) We properly set transport header
2) We use icmp_hdr() helper.

diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c
index 561cd4b8fc6e..ffe25cd1f0e0 100644
--- a/net/ipv4/raw.c
+++ b/net/ipv4/raw.c
@@ -406,11 +406,11 @@ static int raw_send_hdrinc(struct sock *sk, struct flowi4 *fl4,
 			ip_select_ident(net, skb, NULL);
 
 		iph->check = ip_fast_csum((unsigned char *)iph, iph->ihl);
+		skb->transport_header += iphlen;
+		if (iph->protocol == IPPROTO_ICMP &&
+		    length >= iphlen + sizeof(struct icmphdr))
+			icmp_out_count(net, icmp_hdr(skb)->type);
 	}
-	if (iph->protocol == IPPROTO_ICMP)
-		icmp_out_count(net, ((struct icmphdr *)
-			skb_transport_header(skb))->type);
-
 	err = NF_HOOK(NFPROTO_IPV4, NF_INET_LOCAL_OUT, sk, skb,
 		      NULL, rt->dst.dev, dst_output_sk);
 	if (err > 0)


--
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