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=-9.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 83F3CC433EC for ; Mon, 27 Jul 2020 16:25:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 624BF206E7 for ; Mon, 27 Jul 2020 16:25:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=kernel-dk.20150623.gappssmtp.com header.i=@kernel-dk.20150623.gappssmtp.com header.b="AJgFVAeq" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729580AbgG0QZq (ORCPT ); Mon, 27 Jul 2020 12:25:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56624 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729486AbgG0QZp (ORCPT ); Mon, 27 Jul 2020 12:25:45 -0400 Received: from mail-pj1-x1042.google.com (mail-pj1-x1042.google.com [IPv6:2607:f8b0:4864:20::1042]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D5FA5C0619D2 for ; Mon, 27 Jul 2020 09:25:44 -0700 (PDT) Received: by mail-pj1-x1042.google.com with SMTP id c6so3170646pje.1 for ; Mon, 27 Jul 2020 09:25:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20150623.gappssmtp.com; s=20150623; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=PgFDMWbXvBiEOAL8M87yEjCfGoE6x1y/jQ7//nauM8k=; b=AJgFVAeqNc0eTNWKlRiSdboLLmWGtucMVtlkCPLfxpBGGAOOTw7XJMakcq6cwtXPte LEWZgdT2NaR/JInb5XxIN5Smg+ng7vi9zQeZMCLwjk1ov8i28QxqN+dvgNRo6VfRyAGc GBFvwT83gAamdChAgmQR7vLsWjeOfx5Uw2LjnV++DPbvKy39G2ymgTSAdCMm2x6Our1I 94YsqiAYqbGhTjUwF1TYPnjl7nZPE4pLK5AeHvUmbBHlUPuq7gkHP2amjZG1T8c4njdx M1wCjXnOwFI6Xm2Go58ZuKECCu6Tjw7+nmjJ0ZRUF/3Eill1r/Y0cYhEGxbrQi2p6703 1Qlw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=PgFDMWbXvBiEOAL8M87yEjCfGoE6x1y/jQ7//nauM8k=; b=CjAti8KSNE91hWvQwT/FsE/Qd2c6jYkXW7+qfsOxuc04HsAJi4FdoLP66kM13Dd8uQ pL7x9npq9Ul4FEDmLXv/2+p2iw9qBeh1zMuFpfWToVpDrf8iP0oFqB9zQCbo3aKzE3ri r4dijm0lawwdDi8Q+9j/VOPgM9y3vm/xclnaRTiNEgv5gNkkPOfr75fdYVi6x00LJpvM oamTIwBYWKM7NpNADBzzYMTZ8w8IB6iaNUyxIa+4PdCQ98H3XPZP/dmUwUGrA+cvC5qY PboZ4QoXA7jptui5vf6dCLjLGAvWi8388aD5TwnOyV0nlMvYJ0W3oa/9xe5xSo4sd95r YelQ== X-Gm-Message-State: AOAM533rh0kjdAytwhl+rdoizlSNEHuMvltWIFwbfLqsXnhZZeWhPNqV Qt6RG9VVcSfpjHpMFK24s4qI8YRH8Io= X-Google-Smtp-Source: ABdhPJzhbpBDCDrPt1P1xzvTKEDPhAXqIMc+mtjQuLAEnv/alhrt/rhN2nq6GrLuC3iTTLwresjkGw== X-Received: by 2002:a17:902:900b:: with SMTP id a11mr19177442plp.315.1595867144116; Mon, 27 Jul 2020 09:25:44 -0700 (PDT) Received: from [192.168.1.182] ([66.219.217.173]) by smtp.gmail.com with ESMTPSA id v15sm15621045pgo.15.2020.07.27.09.25.43 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 27 Jul 2020 09:25:43 -0700 (PDT) Subject: Re: [Linux-kernel-mentees] [PATCH] block/scsi-ioctl: Prevent kernel-infoleak in scsi_put_cdrom_generic_arg() To: Peilin Ye Cc: Dan Carpenter , Arnd Bergmann , Greg Kroah-Hartman , linux-kernel-mentees@lists.linuxfoundation.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org References: <20200727161932.322955-1-yepeilin.cs@gmail.com> From: Jens Axboe Message-ID: <78d90a98-7bd5-1604-cc27-90842c365ecf@kernel.dk> Date: Mon, 27 Jul 2020 10:25:42 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20200727161932.322955-1-yepeilin.cs@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 7/27/20 10:19 AM, Peilin Ye wrote: > scsi_put_cdrom_generic_arg() is copying uninitialized stack memory to > userspace due to the compiler not initializing holes in statically > allocated structures. Fix it by initializing `cgc32` using memset(). Could also just add the appropriate pad, so the compiler does the right thing. diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c index ef722f04f88a..72108404718f 100644 --- a/block/scsi_ioctl.c +++ b/block/scsi_ioctl.c @@ -651,6 +651,7 @@ struct compat_cdrom_generic_command { compat_int_t stat; compat_caddr_t sense; unsigned char data_direction; + unsigned char pad[3]; compat_int_t quiet; compat_int_t timeout; compat_caddr_t reserved[1]; -- Jens Axboe