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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E1925C433FE for ; Tue, 1 Mar 2022 14:52:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235425AbiCAOxH (ORCPT ); Tue, 1 Mar 2022 09:53:07 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43338 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235348AbiCAOxF (ORCPT ); Tue, 1 Mar 2022 09:53:05 -0500 Received: from mail-qv1-xf2a.google.com (mail-qv1-xf2a.google.com [IPv6:2607:f8b0:4864:20::f2a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AE60749CAD for ; Tue, 1 Mar 2022 06:52:24 -0800 (PST) Received: by mail-qv1-xf2a.google.com with SMTP id d3so16804548qvb.5 for ; Tue, 01 Mar 2022 06:52:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=E4qIR0gbcynkMM7ipUNgXxHtJnS+/1BP2qbABctPj58=; b=T3YPMIJe1af7lUTVV3bFe73oGWTJnD/WaKm7NT6U3TLybc38VVyUhFY/ZZk0vAUhv3 NWZ3Fi28dMn7x3xi0UIXfGe9GXBY9OMv/TJ/itZNQSgmkVHk1a2b1hT/mU/SVXNcvrw4 gY4FhSkdV9LQYeQjCjr+gZncH7wNtx1zQFNSjJcVZeiakOfpHAdqwKYivbHa9iavDZ7g EaYSyuli2AlRgvzr1kWd6PqOx5J4djFmV+JWk35M5myDqLV8IdWPIZrvE5hTIClcoFw1 V0fr2p2ycUkvrZ4SKlaQBQzFCtiGK87NOfUjN5zZGhUqwi25A0dNMjz5AAMbqj6Dr7T7 RS3g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=E4qIR0gbcynkMM7ipUNgXxHtJnS+/1BP2qbABctPj58=; b=VfUfaPNPRWz8OP7bQl9E2A8De1NqCk6BDbHzVoENfFDwS/vap2ilPKa1Fc9HrDpqUp T5lerxjfJWGlTb0FbdcN/8SV5RjZlnWCAXS9uqlQtIy/4JGZ8es2mqWTny0U65zxfQMo tyGw11ozI/pMDXprSK0HVlRUThaIuXSlBPctYatxafjjEHyMaeKuX8IvsMM2K+kFgHiL C+vCVt83DIDsGrnun12ogA2RBysGHBIZlpX0ypf/mJNOqFV6TBVZSvdFpqBtfRZzl0u8 UQ4jiHoTUgF0tvF4q8bMZkK9VwqkqijgdjzEIk4WgTFc/CEbixhEZRm8J9hoTaa10rul 8ZRA== X-Gm-Message-State: AOAM531vkDqnbU2MViABUZfn3QqIoNECDlZHnF6nVR4ej6Bo88yDhWpS MGg60xiaxX7hG20YL6mYu1TYerffKGg= X-Google-Smtp-Source: ABdhPJxM8d3rf4+61QuWR4y1+Co47trb4aiIeRigZ9VTRLnb9N5mr5m7XYkkQjXfDHD+hqlcrFbasg== X-Received: by 2002:a05:6214:21aa:b0:42d:f4ff:fc9 with SMTP id t10-20020a05621421aa00b0042df4ff0fc9mr17364804qvc.49.1646146343827; Tue, 01 Mar 2022 06:52:23 -0800 (PST) Received: from mail-yw1-f178.google.com (mail-yw1-f178.google.com. [209.85.128.178]) by smtp.gmail.com with ESMTPSA id c6-20020ac87d86000000b002ddd9f33ed1sm8833024qtd.44.2022.03.01.06.52.23 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 01 Mar 2022 06:52:23 -0800 (PST) Received: by mail-yw1-f178.google.com with SMTP id 00721157ae682-2db569555d6so90811267b3.12 for ; Tue, 01 Mar 2022 06:52:23 -0800 (PST) X-Received: by 2002:a81:6603:0:b0:2d6:d166:8c31 with SMTP id a3-20020a816603000000b002d6d1668c31mr24731960ywc.351.1646146342611; Tue, 01 Mar 2022 06:52:22 -0800 (PST) MIME-Version: 1.0 References: <20220301144453.snstwdjy3kmpi4zf@begin> In-Reply-To: <20220301144453.snstwdjy3kmpi4zf@begin> From: Willem de Bruijn Date: Tue, 1 Mar 2022 09:51:45 -0500 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH] SO_ZEROCOPY should rather return -ENOPROTOOPT To: Samuel Thibault , willemb@google.com, davem@davemloft.net, kuba@kernel.org, linux-kernel@vger.kernel.org Cc: Network Development Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Mar 1, 2022 at 9:44 AM Samuel Thibault wrote: > > ENOTSUPP is documented as "should never be seen by user programs", and > is not exposed in , so applications cannot safely check against > it. We should rather return the well-known -ENOPROTOOPT. > > Signed-off-by: Samuel Thibault > > diff --git a/net/core/sock.c b/net/core/sock.c > index 4ff806d71921..6e5b84194d56 100644 > --- a/net/core/sock.c > +++ b/net/core/sock.c > @@ -1377,9 +1377,9 @@ int sock_setsockopt(struct socket *sock, int level, int optname, > if (!(sk_is_tcp(sk) || > (sk->sk_type == SOCK_DGRAM && > sk->sk_protocol == IPPROTO_UDP))) > - ret = -ENOTSUPP; > + ret = -ENOPROTOOPT; > } else if (sk->sk_family != PF_RDS) { > - ret = -ENOTSUPP; > + ret = -ENOPROTOOPT; > } > if (!ret) { > if (val < 0 || val > 1) That should have been a public error code. Perhaps rather EOPNOTSUPP. The problem with a change now is that it will confuse existing applications that check for -524 (ENOTSUPP).