From patchwork Wed Feb 3 19:29:52 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Willem de Bruijn X-Patchwork-Id: 12065207 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2CFE4C433DB for ; Wed, 3 Feb 2021 19:31:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DD15364F84 for ; Wed, 3 Feb 2021 19:31:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231153AbhBCTaq (ORCPT ); Wed, 3 Feb 2021 14:30:46 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35684 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229832AbhBCTai (ORCPT ); Wed, 3 Feb 2021 14:30:38 -0500 Received: from mail-qv1-xf2c.google.com (mail-qv1-xf2c.google.com [IPv6:2607:f8b0:4864:20::f2c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 87BEAC06178C for ; Wed, 3 Feb 2021 11:29:58 -0800 (PST) Received: by mail-qv1-xf2c.google.com with SMTP id h21so544884qvb.8 for ; Wed, 03 Feb 2021 11:29:58 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=OBAOidSrXm2Sy3YWpFzBuwWGoxluD1cVMxKH70h9RdA=; b=VvcwiUzaV4GaYHjC04reFXKGPZNzf8sPDljnzOcaFj6isl8heE+W+aC3WVVWIh1RYZ QvPgf7zap2cTNZIBoB83sf0VPWrAkwjsdyeW5zaczqYsrrZEdBcB/NYjf/tKQAwc+d5b qZv3NSQx09nPJl/apPmammstQwGJ3wEn6R3IXuI7mp6eQzO0u1DLNRcnHijYbuHXhMvZ CSFk9Zh5414yO4BHNueOMEaWql6PfZiubz2Bi8l5ikMJY6w4Cs/Vjz7+73Sz986fsDVj UfAIO6OWx8qcNNYStwG52WJWAl8WPTWyZDSy5fgFgOVmOaI9wLA2y44PvAUhYjlC1cvw w1oQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=OBAOidSrXm2Sy3YWpFzBuwWGoxluD1cVMxKH70h9RdA=; b=AtcMvOgqFdXqeAbahaDyfZCGL1gxT0fmzh7MWqri9AbAD+wOb5wo7ZemjUVRKwxLec VF2cV5LMIqddEWvz8YA4F3brDB3a/AO3JTH9fRH+FAcNLdIH84aVUuzDGLyMo8++z1Ms h2qKEMorhiUE8LpYowsxQWPNcStzHdPd3DUP8kDE2terKVHgp8NrY+gf8hosY1nFRGId dh1BA26NpOZalf7k43q0H+SIE363ES9jU0yBguSu4rOmoF/jOPD+tu8ZsA7fUlh5NF96 qqAaU4i/81FG/mOZwYYvda4YjnwOud0h+tLt1Pin8WO19gRCKFin6zbBof+nZrjVuirs LaYg== X-Gm-Message-State: AOAM5308zV1nd8psfhRUXcplS3eNXgU/yy64/44OByXqB8sGlDRBuKk8 cpxrlCnSeVLlNzWxNVhHPQY1cWAAeaw= X-Google-Smtp-Source: ABdhPJypGVbp6daxuqqqhcX0BZcKVcJUqMuChO8YXteg5DQ5SOWG1a0spbI3XNwEIFME3b71C/Tsbg== X-Received: by 2002:a0c:9ac2:: with SMTP id k2mr4374168qvf.3.1612380597373; Wed, 03 Feb 2021 11:29:57 -0800 (PST) Received: from willemb.nyc.corp.google.com ([2620:0:1003:312:2842:1f5d:2de6:8f67]) by smtp.gmail.com with ESMTPSA id c17sm2704135qkb.13.2021.02.03.11.29.54 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 03 Feb 2021 11:29:55 -0800 (PST) From: Willem de Bruijn To: netdev@vger.kernel.org Cc: davem@davemloft.net, kuba@kernel.org, oliver.graute@gmail.com, sagi@grimberg.me, viro@zeniv.linux.org.uk, hch@lst.de, alexander.duyck@gmail.com, eric.dumazet@gmail.com, Willem de Bruijn Subject: [PATCH net v2] udp: fix skb_copy_and_csum_datagram with odd segment sizes Date: Wed, 3 Feb 2021 14:29:52 -0500 Message-Id: <20210203192952.1849843-1-willemdebruijn.kernel@gmail.com> X-Mailer: git-send-email 2.30.0.365.g02bc693789-goog MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org From: Willem de Bruijn When iteratively computing a checksum with csum_block_add, track the offset "pos" to correctly rotate in csum_block_add when offset is odd. The open coded implementation of skb_copy_and_csum_datagram did this. With the switch to __skb_datagram_iter calling csum_and_copy_to_iter, pos was reinitialized to 0 on each call. Bring back the pos by passing it along with the csum to the callback. Changes v1->v2 - pass csum value, instead of csump pointer (Alexander Duyck) Link: https://lore.kernel.org/netdev/20210128152353.GB27281@optiplex/ Fixes: 950fcaecd5cc ("datagram: consolidate datagram copy to iter helpers") Reported-by: Oliver Graute Signed-off-by: Willem de Bruijn Reviewed-by: Alexander Duyck Reviewed-by: Eric Dumazet --- include/linux/uio.h | 8 +++++++- lib/iov_iter.c | 24 ++++++++++++++---------- net/core/datagram.c | 12 ++++++++++-- 3 files changed, 31 insertions(+), 13 deletions(-) diff --git a/include/linux/uio.h b/include/linux/uio.h index 72d88566694e..27ff8eb786dc 100644 --- a/include/linux/uio.h +++ b/include/linux/uio.h @@ -260,7 +260,13 @@ static inline void iov_iter_reexpand(struct iov_iter *i, size_t count) { i->count = count; } -size_t csum_and_copy_to_iter(const void *addr, size_t bytes, void *csump, struct iov_iter *i); + +struct csum_state { + __wsum csum; + size_t off; +}; + +size_t csum_and_copy_to_iter(const void *addr, size_t bytes, void *csstate, struct iov_iter *i); size_t csum_and_copy_from_iter(void *addr, size_t bytes, __wsum *csum, struct iov_iter *i); bool csum_and_copy_from_iter_full(void *addr, size_t bytes, __wsum *csum, struct iov_iter *i); size_t hash_and_copy_to_iter(const void *addr, size_t bytes, void *hashp, diff --git a/lib/iov_iter.c b/lib/iov_iter.c index a21e6a5792c5..f0b2ccb1bb01 100644 --- a/lib/iov_iter.c +++ b/lib/iov_iter.c @@ -592,14 +592,15 @@ static __wsum csum_and_memcpy(void *to, const void *from, size_t len, } static size_t csum_and_copy_to_pipe_iter(const void *addr, size_t bytes, - __wsum *csum, struct iov_iter *i) + struct csum_state *csstate, + struct iov_iter *i) { struct pipe_inode_info *pipe = i->pipe; unsigned int p_mask = pipe->ring_size - 1; + __wsum sum = csstate->csum; + size_t off = csstate->off; unsigned int i_head; size_t n, r; - size_t off = 0; - __wsum sum = *csum; if (!sanity(i)) return 0; @@ -621,7 +622,8 @@ static size_t csum_and_copy_to_pipe_iter(const void *addr, size_t bytes, i_head++; } while (n); i->count -= bytes; - *csum = sum; + csstate->csum = sum; + csstate->off = off; return bytes; } @@ -1522,18 +1524,19 @@ bool csum_and_copy_from_iter_full(void *addr, size_t bytes, __wsum *csum, } EXPORT_SYMBOL(csum_and_copy_from_iter_full); -size_t csum_and_copy_to_iter(const void *addr, size_t bytes, void *csump, +size_t csum_and_copy_to_iter(const void *addr, size_t bytes, void *_csstate, struct iov_iter *i) { + struct csum_state *csstate = _csstate; const char *from = addr; - __wsum *csum = csump; __wsum sum, next; - size_t off = 0; + size_t off; if (unlikely(iov_iter_is_pipe(i))) - return csum_and_copy_to_pipe_iter(addr, bytes, csum, i); + return csum_and_copy_to_pipe_iter(addr, bytes, _csstate, i); - sum = *csum; + sum = csstate->csum; + off = csstate->off; if (unlikely(iov_iter_is_discard(i))) { WARN_ON(1); /* for now */ return 0; @@ -1561,7 +1564,8 @@ size_t csum_and_copy_to_iter(const void *addr, size_t bytes, void *csump, off += v.iov_len; }) ) - *csum = sum; + csstate->csum = sum; + csstate->off = off; return bytes; } EXPORT_SYMBOL(csum_and_copy_to_iter); diff --git a/net/core/datagram.c b/net/core/datagram.c index 81809fa735a7..15ab9ffb27fe 100644 --- a/net/core/datagram.c +++ b/net/core/datagram.c @@ -721,8 +721,16 @@ static int skb_copy_and_csum_datagram(const struct sk_buff *skb, int offset, struct iov_iter *to, int len, __wsum *csump) { - return __skb_datagram_iter(skb, offset, to, len, true, - csum_and_copy_to_iter, csump); + struct csum_state csdata = { .csum = *csump }; + int ret; + + ret = __skb_datagram_iter(skb, offset, to, len, true, + csum_and_copy_to_iter, &csdata); + if (ret) + return ret; + + *csump = csdata.csum; + return 0; } /**