From mboxrd@z Thu Jan 1 00:00:00 1970 From: Patrick McHardy Subject: Re: [PATCHv2] netfilter: Remove skb_is_nonlinear check from nf_conntrack_sip Date: Fri, 14 May 2010 20:42:43 +0200 Message-ID: <4BED99A3.2050404@trash.net> References: <20100514180138.GF15969@obsidianresearch.com> <4BED92AF.50704@trash.net> <20100514182601.GJ15969@obsidianresearch.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Cc: netfilter-devel@vger.kernel.org, netdev@vger.kernel.org To: Jason Gunthorpe Return-path: In-Reply-To: <20100514182601.GJ15969@obsidianresearch.com> Sender: netdev-owner@vger.kernel.org List-Id: netfilter-devel.vger.kernel.org Jason Gunthorpe wrote: > On Fri, May 14, 2010 at 08:13:03PM +0200, Patrick McHardy wrote: >> Your patch is based on an old version, the current version also >> supports TCP. I'll commit this patch to my tree after some testing. > > Thanks! > >> diff --git a/net/netfilter/nf_conntrack_sip.c b/net/netfilter/nf_conntrack_sip.c >> index b20f427..45750cc 100644 >> +++ b/net/netfilter/nf_conntrack_sip.c >> @@ -1393,10 +1393,8 @@ static int sip_help_tcp(struct sk_buff *skb, unsigned int protoff, >> >> nf_ct_refresh(ct, skb, sip_timeout * HZ); >> >> - if (skb_is_nonlinear(skb)) { >> - pr_debug("Copy of skbuff not supported yet.\n"); >> + if (unlikely(skb_linearize(skb))) >> return NF_ACCEPT; >> - } > > Should this be NF_DROP? As I understand it skb_linearize only failes > if it runs out of memory, which probably means dropping is OK. But > passing a packet that might need rewriting could be harmful.. We so far also didn't rewrite the packet. But agreed, its a corner case and dropping it is the safer choice.