From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Thu, 10 May 2012 23:07:37 -0400 (EDT) Message-Id: <20120510.230737.585788465862567756.davem@davemloft.net> To: ben@decadent.org.uk Cc: jrnieder@gmail.com, linux-kernel@vger.kernel.org, stable@vger.kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, eric.dumazet@gmail.com, subramanian.vijay@gmail.com Subject: Re: [ 074/167] [PATCH 14/26] tcp: fix tcp_trim_head() From: David Miller In-Reply-To: <1336705215.8274.425.camel@deadeye> References: <20120509055040.099618905@decadent.org.uk> <20120509081617.GD32230@burratino> <1336705215.8274.425.camel@deadeye> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: From: Ben Hutchings Date: Fri, 11 May 2012 04:00:15 +0100 > On Wed, 2012-05-09 at 03:16 -0500, Jonathan Nieder wrote: >> Ben Hutchings wrote: >> >> > 3.2-stable review patch. If anyone has any objections, please let me know. >> [...] >> > [ Upstream commit 4fa48bf3c75069d636fc8830743c929a062e80dc ] >> > >> > commit f07d960df3 (tcp: avoid frag allocation for small frames) >> > breaked assumption in tcp stack that skb is either linear (skb->data_len >> > == 0), or fully fragged (skb->data_len == skb->len) >> > >> > tcp_trim_head() made this assumption, we must fix it. >> >> Is this needed in the context of 3.2.y (which does not include >> f07d960df3)? > [...] > > The code being replaced really didn't make sense, but unless there is > some other case that breaks the assumption described then I don't think > this meets the stable rules. David? It's a prerequisite for cleanly applying the patch that comes right afterwards.