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 4AC4BC35DF2 for ; Tue, 25 Feb 2020 05:58:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1A86D21556 for ; Tue, 25 Feb 2020 05:58:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="aAGSYtEi" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727018AbgBYF6f (ORCPT ); Tue, 25 Feb 2020 00:58:35 -0500 Received: from mail-pl1-f195.google.com ([209.85.214.195]:46894 "EHLO mail-pl1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725783AbgBYF6f (ORCPT ); Tue, 25 Feb 2020 00:58:35 -0500 Received: by mail-pl1-f195.google.com with SMTP id y8so5025411pll.13 for ; Mon, 24 Feb 2020 21:58:33 -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=aL8HKc/o91pieXxtZUmutnJ9MzrPiOY52OcfTyzO3tQ=; b=aAGSYtEiWE7jghj1DaUabB+/pW4SPjW4fd/jB0FYcj+KI7+aOVcQcv+a5z3NnkKaLk SB1aD+h8X0FiF7+LWVu69ImZcMiDDFa08lMXu/B+nERklYrqzEZjvCWdj4ExajibthBS zGKiZGxhV9CA6pJDO+LG/CAr2jTmljg6LTQrhLgzmWK15W6GuHxUp/8P/1lz2plU6T9F IP6dHDGIG7tSb/jn3aolwSm1NuSeSLfJmeGP0oS/0YK1QaqvrQ4dl7J7J/o2c199WZip iw8ytwjnxxNr6ywgLY5QeZ5lmKIQkDNH7B1uuQZK1LivVRWdjAnsT15oQhmTnXOya8CY hZzA== 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=aL8HKc/o91pieXxtZUmutnJ9MzrPiOY52OcfTyzO3tQ=; b=jHGHe/P8RWVi84A4aRQN6PBjTt68lZlL1nXW5QAAIMjtBq8CJLoJ/9Y9t56rSB71n/ NA9rYiXfTIe26/hg3U8g10TJkO95JEUM34Cj/v2vfqjUJJkkeJfySIJFLhGYgRpYpiiQ +XgCL31cb4G3zjC27mAAmDAhFPl2ff7dZL8GSkHhn7KO7n7a26Ms4DMznNGGGr7TH0yb 5XVONl8BYx8r/6oE2W1aWMsu4ySaWS8c+vebYpbPySLhzuH4vtjEKa061Qb52M33VSrb 1/YErx0PCPoG3Di0DRDgRvTED5UM+wtEha9fi54kuw06uY4mftXXRsdsCG85siyNqHmY wr2A== X-Gm-Message-State: APjAAAUBBmhB0cfnwoa0o2bX4LmbzOByibcto7h44IRL+o6yeUYi4YU8 z6kp9T2/H1Re7my67G6RAng= X-Google-Smtp-Source: APXvYqzj8ah2m+pb28FMF9JbCvbIf7kUma/2EtgcKJR8Lph1es1xJ8LDKtboycsj2HysUH/3Rf9L/g== X-Received: by 2002:a17:902:b98d:: with SMTP id i13mr1088234pls.250.1582610313054; Mon, 24 Feb 2020 21:58:33 -0800 (PST) Received: from phantasmagoria.svl.corp.google.com ([2620:15c:2c4:201:2b0a:8c1:6a84:1aa0]) by smtp.gmail.com with ESMTPSA id x6sm7158536pgb.70.2020.02.24.21.58.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 24 Feb 2020 21:58:32 -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 21:58:06 -0800 Message-Id: <20200225055806.74881-1-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 --- 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