From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932189AbcAHMKf (ORCPT ); Fri, 8 Jan 2016 07:10:35 -0500 Received: from mail-lf0-f41.google.com ([209.85.215.41]:34162 "EHLO mail-lf0-f41.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932107AbcAHMKd (ORCPT ); Fri, 8 Jan 2016 07:10:33 -0500 MIME-Version: 1.0 In-Reply-To: <145225444176.22215.2003378381077166898.stgit@zurg> References: <145225444176.22215.2003378381077166898.stgit@zurg> Date: Fri, 8 Jan 2016 15:10:31 +0300 Message-ID: Subject: Re: [PATCH] net: preserve IP control block during GSO segmentation From: Konstantin Khlebnikov To: Linux Kernel Network Developers , "David S. Miller" Cc: dev@openvswitch.org, Thadeu Lima de Souza Cascardo , Eric Dumazet , Florian Westphal , Linux Kernel Mailing List , Pravin Shelar , Cong Wang Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jan 8, 2016 at 3:00 PM, Konstantin Khlebnikov wrote: > Skb_gso_segment() uses skb control block during segmentation. > This patch adds 32-bytes room for previous control block which > will be copied into all resulting segments. > > This patch fixes kernel crash during fragmenting forwarded packets. > Fragmentation requires valid IP CB in skb for clearing ip options. > Also patch removes custom save/restore in ovs code, now it's redundant. > > Signed-off-by: Konstantin Khlebnikov > Link: http://lkml.kernel.org/r/CALYGNiP-0MZ-FExV2HutTvE9U-QQtkKSoE--KN=JQE5STYsjAA@mail.gmail.com This patch is alternative for [PATCH] net: prevent corruption of skb when using skb_gso_segment by Thadeu Lima de Souza Cascardo. This version have no stack allocations and no changes in code. It just shifts gso cb. From mboxrd@z Thu Jan 1 00:00:00 1970 From: Konstantin Khlebnikov Subject: Re: [PATCH] net: preserve IP control block during GSO segmentation Date: Fri, 8 Jan 2016 15:10:31 +0300 Message-ID: References: <145225444176.22215.2003378381077166898.stgit@zurg> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Cc: dev-yBygre7rU0TnMu66kgdUjQ@public.gmane.org, Florian Westphal , Linux Kernel Mailing List , Eric Dumazet , Cong Wang To: Linux Kernel Network Developers , "David S. Miller" Return-path: In-Reply-To: <145225444176.22215.2003378381077166898.stgit@zurg> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces-yBygre7rU0TnMu66kgdUjQ@public.gmane.org Sender: "dev" List-Id: netdev.vger.kernel.org T24gRnJpLCBKYW4gOCwgMjAxNiBhdCAzOjAwIFBNLCBLb25zdGFudGluIEtobGVibmlrb3YgPGtv Y3Q5aUBnbWFpbC5jb20+IHdyb3RlOgo+IFNrYl9nc29fc2VnbWVudCgpIHVzZXMgc2tiIGNvbnRy b2wgYmxvY2sgZHVyaW5nIHNlZ21lbnRhdGlvbi4KPiBUaGlzIHBhdGNoIGFkZHMgMzItYnl0ZXMg cm9vbSBmb3IgcHJldmlvdXMgY29udHJvbCBibG9jayB3aGljaAo+IHdpbGwgYmUgY29waWVkIGlu dG8gYWxsIHJlc3VsdGluZyBzZWdtZW50cy4KPgo+IFRoaXMgcGF0Y2ggZml4ZXMga2VybmVsIGNy YXNoIGR1cmluZyBmcmFnbWVudGluZyBmb3J3YXJkZWQgcGFja2V0cy4KPiBGcmFnbWVudGF0aW9u IHJlcXVpcmVzIHZhbGlkIElQIENCIGluIHNrYiBmb3IgY2xlYXJpbmcgaXAgb3B0aW9ucy4KPiBB bHNvIHBhdGNoIHJlbW92ZXMgY3VzdG9tIHNhdmUvcmVzdG9yZSBpbiBvdnMgY29kZSwgbm93IGl0 J3MgcmVkdW5kYW50Lgo+Cj4gU2lnbmVkLW9mZi1ieTogS29uc3RhbnRpbiBLaGxlYm5pa292IDxr b2N0OWlAZ21haWwuY29tPgo+IExpbms6IGh0dHA6Ly9sa21sLmtlcm5lbC5vcmcvci9DQUxZR05p UC0wTVotRkV4VjJIdXRUdkU5VS1RUXRrS1NvRS0tS049SlFFNVNUWXNqQUFAbWFpbC5nbWFpbC5j b20KClRoaXMgcGF0Y2ggaXMgYWx0ZXJuYXRpdmUgZm9yIFtQQVRDSF0gbmV0OiBwcmV2ZW50IGNv cnJ1cHRpb24gb2Ygc2tiIHdoZW4gdXNpbmcKc2tiX2dzb19zZWdtZW50IGJ5IFRoYWRldSBMaW1h IGRlIFNvdXphIENhc2NhcmRvLiBUaGlzIHZlcnNpb24gaGF2ZQpubyBzdGFjayBhbGxvY2F0aW9u cyBhbmQgbm8gY2hhbmdlcyBpbiBjb2RlLiBJdCBqdXN0IHNoaWZ0cyBnc28gY2IuCl9fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fCmRldiBtYWlsaW5nIGxpc3QK ZGV2QG9wZW52c3dpdGNoLm9yZwpodHRwOi8vb3BlbnZzd2l0Y2gub3JnL21haWxtYW4vbGlzdGlu Zm8vZGV2Cg==