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=-10.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 2D6DCC433E1 for ; Wed, 26 Aug 2020 19:43:28 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 71FCC2076C for ; Wed, 26 Aug 2020 19:43:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="c0wPYmSc" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 71FCC2076C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=chromium.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-19668-kernel-hardening=archiver.kernel.org@lists.openwall.com Received: (qmail 1052 invoked by uid 550); 26 Aug 2020 19:43:21 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Received: (qmail 1026 invoked from network); 26 Aug 2020 19:43:21 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=sSiqGYhL6mx7GdlZDbkT4CADd/LuyDj2qvehSXEkfFs=; b=c0wPYmScaFMOZj7JWatRYkrF0jD6jFzMN0Md0N1TNOWQ9Ph4qv2dl5i7bl2XuK/2g8 QKQ+2ztblAFVz0LXeFtgAblEZtefFyuhCfkrAiGsrXjmDzeryGjhlqYD71z0uo1vnxHD Gt8H/Qw2aAnM1D6yPctfoHqtXYkRpOmyeWoJQ= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=sSiqGYhL6mx7GdlZDbkT4CADd/LuyDj2qvehSXEkfFs=; b=Q2OkaIuO4tr0SvCetR7L/+TqMvV1tlQePPwmnWNX7o8GgO8UcRG9eYinSndMN8uIwd 8BU2VYX5xhIh4mBQCk/zE5liK1vSk2A5ieYPF2/g6DcQ8zXTY9w7wjBMkxjwXU7vcfTn Qt/XZuhgEmhb9+YRNY553pJFrtVr+K2ic7NCdddWqgij9Xoq2xXNRwkQ8leMA+CYEFgD wS5QiBFpgYJHw82lf3OObDblJegNgaeeyOhRA2rc4wSw3h6gx9PjBV3IzKTNPpiQDmOC 0GyOdkAw1IVwK9oahVmRK/BBh8ERgCJz62qkBm1akCjTayq9LWnsfnJOLv6I+0fn1TUt GXDw== X-Gm-Message-State: AOAM531g3OT8dcRhEaNv2EIBSCKoSBu9k99Yg3HSZIiUMcXb9WWSGqiZ uRXLNYu3wmNY8SAh8HBHUHLJoQ== X-Google-Smtp-Source: ABdhPJyQnpR7N2xazFbp7J7MUFKkTkxsUr7ZQgxByGJ39DlvvIGGA/PzpplC4Eu0qakGcWY/M93Ulg== X-Received: by 2002:a63:4450:: with SMTP id t16mr11747991pgk.3.1598470989316; Wed, 26 Aug 2020 12:43:09 -0700 (PDT) Date: Wed, 26 Aug 2020 12:43:07 -0700 From: Kees Cook To: Stefano Garzarella Cc: Jens Axboe , Christian Brauner , Jann Horn , Jeff Moyer , linux-fsdevel@vger.kernel.org, Sargun Dhillon , Alexander Viro , Kernel Hardening , Stefan Hajnoczi , linux-kernel@vger.kernel.org, Aleksa Sarai , io-uring@vger.kernel.org Subject: Re: [PATCH v4 1/3] io_uring: use an enumeration for io_uring_register(2) opcodes Message-ID: <202008261241.074D8765@keescook> References: <20200813153254.93731-1-sgarzare@redhat.com> <20200813153254.93731-2-sgarzare@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200813153254.93731-2-sgarzare@redhat.com> On Thu, Aug 13, 2020 at 05:32:52PM +0200, Stefano Garzarella wrote: > The enumeration allows us to keep track of the last > io_uring_register(2) opcode available. > > Behaviour and opcodes names don't change. > > Signed-off-by: Stefano Garzarella > --- > include/uapi/linux/io_uring.h | 27 ++++++++++++++++----------- > 1 file changed, 16 insertions(+), 11 deletions(-) > > diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h > index d65fde732518..cdc98afbacc3 100644 > --- a/include/uapi/linux/io_uring.h > +++ b/include/uapi/linux/io_uring.h > @@ -255,17 +255,22 @@ struct io_uring_params { > /* > * io_uring_register(2) opcodes and arguments > */ > -#define IORING_REGISTER_BUFFERS 0 > -#define IORING_UNREGISTER_BUFFERS 1 > -#define IORING_REGISTER_FILES 2 > -#define IORING_UNREGISTER_FILES 3 > -#define IORING_REGISTER_EVENTFD 4 > -#define IORING_UNREGISTER_EVENTFD 5 > -#define IORING_REGISTER_FILES_UPDATE 6 > -#define IORING_REGISTER_EVENTFD_ASYNC 7 > -#define IORING_REGISTER_PROBE 8 > -#define IORING_REGISTER_PERSONALITY 9 > -#define IORING_UNREGISTER_PERSONALITY 10 > +enum { > + IORING_REGISTER_BUFFERS, Actually, one *tiny* thought. Since this is UAPI, do we want to be extra careful here and explicitly assign values? We can't change the meaning of a number (UAPI) but we can add new ones, etc? This would help if an OP were removed (to stop from triggering a cascade of changed values)... for example: enum { IORING_REGISTER_BUFFERS = 0, IORING_UNREGISTER_BUFFERS = 1, ... -- Kees Cook