From patchwork Wed Jan 28 09:58:11 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Karl Beldan X-Patchwork-Id: 434288 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id D95921401EF for ; Thu, 29 Jan 2015 13:16:57 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932207AbbA2CQ2 (ORCPT ); Wed, 28 Jan 2015 21:16:28 -0500 Received: from mail-wi0-f178.google.com ([209.85.212.178]:41067 "EHLO mail-wi0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753777AbbA2CQ0 (ORCPT ); Wed, 28 Jan 2015 21:16:26 -0500 Received: by mail-wi0-f178.google.com with SMTP id bs8so9773731wib.5; Wed, 28 Jan 2015 18:16:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:cc:subject:date:message-id; bh=O1yWSf31FhDliY8Kvs1SVzuKUEfj/EzDeII4OaCyYLE=; b=yam+p6LbI8AzC6FH2sTM7U5X5U+BBC6vEx1caJT90TU/QqR5t4V/K/N5PLb6j3skft jJjAt8u2VAeA1f9aXylxr4B4bH+ekq+1e7ywz+zF00AQPWCRyfTF88mVYTCb5UiwqLwS I1kUPL9rAB1fDfa+VJQTpNx07+pYTOYf13koZ2Vn0Ud2c76+4lDh1hFDPGtjwxt87YCD w4ywHCpAXZUyAhp5syqbAd9c70zUvSoCgbl21Gk0bIFAgQVPb5SnWBkyzl3I6+2WSTLy v51e4fkUQqXbHI18tifPtdk9zfZdMrsYfqgx82cZ5bthwxl6sQsF/vGiC1N0JnSa3CaV Guog== X-Received: by 10.180.20.177 with SMTP id o17mr5389380wie.20.1422439153627; Wed, 28 Jan 2015 01:59:13 -0800 (PST) Received: from magnum.frso.rivierawaves.com (vpn.rivierawaves.com. [91.151.119.162]) by mx.google.com with ESMTPSA id q10sm5329897wjr.41.2015.01.28.01.59.12 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Wed, 28 Jan 2015 01:59:12 -0800 (PST) From: Karl Beldan X-Google-Original-From: Karl Beldan Cc: Karl Beldan , Karl Beldan , Al Viro , Eric Dumazet , Arnd Bergmann , Mike Frysinger , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: [PATCH v2] lib/checksum.c: fix carry in csum_tcpudp_nofold Date: Wed, 28 Jan 2015 10:58:11 +0100 Message-Id: <1422439091-31413-1-git-send-email-karl.beldan@rivierawaves.com> X-Mailer: git-send-email 2.0.1 To: unlisted-recipients:; (no To-header on input) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org The carry from the 64->32bits folding was dropped, e.g with: saddr=0xFFFFFFFF daddr=0xFF0000FF len=0xFFFF proto=0 sum=1, csum_tcpudp_nofold returned 0 instead of 1. Signed-off-by: Karl Beldan Cc: Al Viro Cc: Eric Dumazet Cc: Arnd Bergmann Cc: Mike Frysinger Cc: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: stable@vger.kernel.org Signed-off-by: Eric Dumazet --- lib/checksum.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/lib/checksum.c b/lib/checksum.c index 129775e..fcf3894 100644 --- a/lib/checksum.c +++ b/lib/checksum.c @@ -47,6 +47,15 @@ static inline unsigned short from32to16(unsigned int x) return x; } +static inline u32 from64to32(u64 x) +{ + /* add up 32-bit and 32-bit for 32+c bit */ + x = (x & 0xffffffff) + (x >> 32); + /* add up carry.. */ + x = (x & 0xffffffff) + (x >> 32); + return (u32)x; +} + static unsigned int do_csum(const unsigned char *buff, int len) { int odd; @@ -195,8 +204,7 @@ __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr, #else s += (proto + len) << 8; #endif - s += (s >> 32); - return (__force __wsum)s; + return (__force __wsum)from64to32(s); } EXPORT_SYMBOL(csum_tcpudp_nofold); #endif