From mboxrd@z Thu Jan 1 00:00:00 1970 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=-9.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 6527BC35DF2 for ; Tue, 25 Feb 2020 06:06:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2C05521556 for ; Tue, 25 Feb 2020 06:06:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="nbX9S2G/" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726400AbgBYGGZ (ORCPT ); Tue, 25 Feb 2020 01:06:25 -0500 Received: from mail-pj1-f66.google.com ([209.85.216.66]:50480 "EHLO mail-pj1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725837AbgBYGGZ (ORCPT ); Tue, 25 Feb 2020 01:06:25 -0500 Received: by mail-pj1-f66.google.com with SMTP id r67so794773pjb.0 for ; Mon, 24 Feb 2020 22:06:24 -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=NL+8QKcJIo9UjBfd77xLS5pLZL6WsmvH9RUdBt70aro=; b=nbX9S2G/Q+e5Mkiqv0RyvMX545B8rseKqiX9RmmWnsKFUHy4uKTyiYGVR04BWIGMGn ANz3Jv3/jZ8nlZHGOFOVJZTcm7efE+hQbIT+Phx4CeDWX8+TvbVTYgLC5KPQHZHDsdko HZY3Ds74HulEYwaavIfbL0+MybZ5WXElnkcgMjSqO5ZV33eci3E+koI78uWKjFn1Zpok WVBBf03Ua7PfZ+/OznguF6CECcKQDdta8Lq/52159hA4D8TVOVkUhtv4vjOMQYQ51DMk GNqvfkic9kibKeQikWGFPIGkU/AshDnmxa610dPzGsPpNbj/Sb3sMC8SUapAeYR0rLl3 ktxw== 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=NL+8QKcJIo9UjBfd77xLS5pLZL6WsmvH9RUdBt70aro=; b=Y0TLLaV52xnJoJvCr1a24TqYDV54Doms8uufLnMHsOOyBbnJtr9XqTgDlNs3NzYabV HJorDqu6lb8XaZSuVSMiuI5uYnQd4PZplIhCHj1R5qZI8VOKJgKpXi/yKLDbko0A4w8b JM+Pno3eRtOutFyp4dFrjkUYW62EqAdicB1CX2PCpWz+Xg3p48803BkWNoSy0UbjS757 rEYgEVAC7UflUl4ArEIzztzWOVnfzWiZmchLS8duVZ6B/95xxNWHVTSUX5Y+gHWwvEHJ fanA/d0crqCw4QR9+ki7oedJEmBH9HtPD1kZeitpeE2/yUGGySjdwv8yJ3SUiyVsbzPk O3Ng== X-Gm-Message-State: APjAAAVeQRSD3GX5ZL/ux1B1ODnlmi02hYB0g+DQwIsnK3LTEuZAM9aC NbRF3Jo8ZqKz5G6BAZ+wJmw= X-Google-Smtp-Source: APXvYqwo68ka3H5KHHir1p7/XcV8T+ufeMVKJt56gf9Yu3OmpQNTLdIXDyY4PlgwE5CBckLy2G7w6Q== X-Received: by 2002:a17:902:bb93:: with SMTP id m19mr55053436pls.310.1582610784494; Mon, 24 Feb 2020 22:06:24 -0800 (PST) Received: from phantasmagoria.svl.corp.google.com ([2620:15c:2c4:201:2b0a:8c1:6a84:1aa0]) by smtp.gmail.com with ESMTPSA id s7sm1529990pjk.22.2020.02.24.22.06.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 24 Feb 2020 22:06:23 -0800 (PST) From: Arjun Roy To: davem@davemloft.net, netdev@vger.kernel.org Cc: arjunroy@google.com, soheil@google.com, edumazet@google.com, willemb@google.com Subject: [PATCH net-next] tcp-zerocopy: Update returned getsockopt() optlen. Date: Mon, 24 Feb 2020 22:06:20 -0800 Message-Id: <20200225060620.76486-1-arjunroy.kdev@gmail.com> X-Mailer: git-send-email 2.25.0.265.gbab2e86ba0-goog MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Arjun Roy TCP receive zerocopy currently does not update the returned optlen for getsockopt(). Thus, userspace cannot properly determine if all the fields are set in the passed-in struct. This patch sets the optlen before return, in keeping with the expected operation of getsockopt(). Signed-off-by: Arjun Roy Signed-off-by: Eric Dumazet Signed-off-by: Soheil Hassas Yeganeh Signed-off-by: Willem de Bruijn Fixes: c8856c051454 ("tcp-zerocopy: Return inq along with tcp receive zerocopy.") --- net/ipv4/tcp.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 600deb39f17de..fb9894d3d30e9 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -4148,8 +4148,12 @@ static int do_tcp_getsockopt(struct sock *sk, int level, zerocopy_rcv_inq: zc.inq = tcp_inq_hint(sk); zerocopy_rcv_out: - if (!err && copy_to_user(optval, &zc, len)) - err = -EFAULT; + if (!err) { + if (put_user(len, optlen)) + return -EFAULT; + if (copy_to_user(optval, &zc, len)) + return -EFAULT; + } return err; } #endif -- 2.25.0.265.gbab2e86ba0-goog