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 985ACC35E01 for ; Tue, 25 Feb 2020 20:39:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6CB8220675 for ; Tue, 25 Feb 2020 20:39:05 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="nN7tdWIf" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731860AbgBYUjE (ORCPT ); Tue, 25 Feb 2020 15:39:04 -0500 Received: from mail-pj1-f68.google.com ([209.85.216.68]:33928 "EHLO mail-pj1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728119AbgBYUjE (ORCPT ); Tue, 25 Feb 2020 15:39:04 -0500 Received: by mail-pj1-f68.google.com with SMTP id f2so1368892pjq.1 for ; Tue, 25 Feb 2020 12:39:03 -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=0sQIbI7dBNLv69VANmscf3kTolWr8JxCUdMFG96rkYc=; b=nN7tdWIfojfI4nX3ebOyntvIy8OKYbZurdDqGQAyiHFxI46/v9P+hmaS0jgFBfcMct WJqdMxLE1ImzscclDZMarEfQ4xO4EoSIaDMbXxJcksfAbndg4mz09YDkIixPe8vf5Tf8 8H1PTrd2IV3Ab8xP6+1qNdffBgqfWe8JF3JOqBtQDE3D/y02jjOuo8KqXSNM9RCe5+NG 33shaNKZrUdwQVfbxnmB1Hf16hysNK90AY9zCMI7kT158G/P2k568mOcXyxprgNCQHUE jn0dNJ+wTsjmQN27uvVqq3yx5n5JsB9gQRaYSe+5Z8sYVxXYdtLrJnfE5/drHo+LsbSB zWvA== 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=0sQIbI7dBNLv69VANmscf3kTolWr8JxCUdMFG96rkYc=; b=oVZWYmrW1zYCaKYc3UzvenjttEquUh5SAcECkvhGjJjJ85dm1HYwPEbE+I/ZO3vHb9 nGVyq3ezoYvudGkMhJ5OnIDPJ68BkgXv5tEk2zJCl/MBWeiab8c2pECzpuOhOHjBDMIX AMp4VUz6HM2xPtqEbu7+HGxV1ZraE1g2wfZCnz5V9yyRJKSKZxTgDXvQsbQx3/wJSoWE 53pPqH5fCt6MVKlzcaq0sBP+fBShpiBXfaYopyBkCjUChPNGvgj7JHYFeDB+q+AWOiTX BI/E2ZZBMlttb5siIkrBfs+Ce04cAYW+bKEziXHHHV1eaKCNrXB/lo7h0W7TQWMgXRu4 NkpA== X-Gm-Message-State: APjAAAXR5lHTL2pb0vbFZ8OiV3J75KT5+ggNLg/BPUrvjksIGj8go1vi 3q3dyOnT3obBf8ImyE/WyYU= X-Google-Smtp-Source: APXvYqzYlrfnti+Ws8CI6bIVyArXSp4kEjzCyWXGniVa4VoiZExo0DN5xeFEe8EjLAcn83QcxOylhA== X-Received: by 2002:a17:90a:9416:: with SMTP id r22mr995925pjo.2.1582663142772; Tue, 25 Feb 2020 12:39:02 -0800 (PST) Received: from phantasmagoria.svl.corp.google.com ([2620:15c:2c4:201:2b0a:8c1:6a84:1aa0]) by smtp.gmail.com with ESMTPSA id e30sm9641pga.6.2020.02.25.12.39.01 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 25 Feb 2020 12:39:02 -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 v2 net-next] tcp-zerocopy: Update returned getsockopt() optlen. Date: Tue, 25 Feb 2020 12:38:54 -0800 Message-Id: <20200225203854.184524-1-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() if the user passed in a larger than expected value. Thus, userspace cannot properly determine if all the fields are set in the passed-in struct. This patch sets the optlen for this case before returning, in keeping with the expected operation of getsockopt(). Fixes: c8856c051454 ("tcp-zerocopy: Return inq along with tcp receive zerocopy.") 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 | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 600deb39f17de..9644047262ece 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -4124,8 +4124,11 @@ static int do_tcp_getsockopt(struct sock *sk, int level, return -EFAULT; if (len < offsetofend(struct tcp_zerocopy_receive, length)) return -EINVAL; - if (len > sizeof(zc)) + if (len > sizeof(zc)) { len = sizeof(zc); + if (put_user(len, optlen)) + return -EFAULT; + } if (copy_from_user(&zc, optval, len)) return -EFAULT; lock_sock(sk); -- 2.25.0.265.gbab2e86ba0-goog