netdev - [PATCHv2] netfilter: Remove skb_is_nonlinear check from nf_conntrack

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-next>] [day] [month] [year] [list]

Message-ID: <20100514180138.GF15969@obsidianresearch.com>
Date:	Fri, 14 May 2010 12:01:38 -0600
From:	Jason Gunthorpe <jgunthorpe@...idianresearch.com>
To:	netfilter-devel@...r.kernel.org, netdev@...r.kernel.org,
	Patrick McHardy <kaber@...sh.net>
Subject: [PATCHv2] netfilter: Remove skb_is_nonlinear check from
	nf_conntrack_sip

At least the XEN net front driver always produces non linear skbs,
so the SIP module does nothing at all when used with that NIC.

Unconditionally linearize the skb..

Signed-off-by: Jason Gunthorpe <jgunthorpe@...idianresearch.com>
---
 net/netfilter/nf_conntrack_sip.c |    9 +++------
 1 files changed, 3 insertions(+), 6 deletions(-)

Patrick/Jan, thanks.. This is what I wanted to do in the first place,
but I couldn't convince myself it was safe, as no other nf code does
this..

Unfortunately I can no longer test it :(
 
diff --git a/net/netfilter/nf_conntrack_sip.c b/net/netfilter/nf_conntrack_sip.c
index 4b57216..02d0b59 100644
--- a/net/netfilter/nf_conntrack_sip.c
+++ b/net/netfilter/nf_conntrack_sip.c
@@ -1275,13 +1275,10 @@ static int sip_help(struct sk_buff *skb,
 
 	nf_ct_refresh(ct, skb, sip_timeout * HZ);
 
-	if (!skb_is_nonlinear(skb))
-		dptr = skb->data + dataoff;
-	else {
-		pr_debug("Copy of skbuff not supported yet.\n");
-		return NF_ACCEPT;
-	}
+	if (unlikely(skb_linearize(skb)))
+		return NF_DROP;
 
+	dptr = skb->data + dataoff;
 	datalen = skb->len - dataoff;
 	if (datalen < strlen("SIP/2.0 200"))
 		return NF_ACCEPT;
-- 
1.6.0.4

--
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