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=-5.5 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no 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 46B7EC433F7 for ; Thu, 16 Jul 2020 09:43:08 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 270F52071B for ; Thu, 16 Jul 2020 09:43:08 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 270F52071B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=i-love.sakura.ne.jp Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 40E7C6EC3E; Thu, 16 Jul 2020 09:42:50 +0000 (UTC) Received: from www262.sakura.ne.jp (www262.sakura.ne.jp [202.181.97.72]) by gabe.freedesktop.org (Postfix) with ESMTPS id 6C8E86EB9E for ; Wed, 15 Jul 2020 15:29:07 +0000 (UTC) Received: from fsav101.sakura.ne.jp (fsav101.sakura.ne.jp [27.133.134.228]) by www262.sakura.ne.jp (8.15.2/8.15.2) with ESMTP id 06FFT1XC042748; Thu, 16 Jul 2020 00:29:01 +0900 (JST) (envelope-from penguin-kernel@i-love.sakura.ne.jp) Received: from www262.sakura.ne.jp (202.181.97.72) by fsav101.sakura.ne.jp (F-Secure/fsigk_smtp/550/fsav101.sakura.ne.jp); Thu, 16 Jul 2020 00:29:01 +0900 (JST) X-Virus-Status: clean(F-Secure/fsigk_smtp/550/fsav101.sakura.ne.jp) Received: from [192.168.1.9] (M106072142033.v4.enabler.ne.jp [106.72.142.33]) (authenticated bits=0) by www262.sakura.ne.jp (8.15.2/8.15.2) with ESMTPSA id 06FFT1MI042742 (version=TLSv1.2 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Thu, 16 Jul 2020 00:29:01 +0900 (JST) (envelope-from penguin-kernel@i-love.sakura.ne.jp) Subject: Re: [PATCH v2] fbdev: Detect integer underflow at "struct fbcon_ops"->clear_margins. To: Dan Carpenter References: <20200715015102.3814-1-penguin-kernel@I-love.SAKURA.ne.jp> <20200715094836.GD2571@kadam> <9e6eac10-c5c3-f518-36cc-9ea32fb5d7fe@i-love.sakura.ne.jp> <20200715151220.GE2571@kadam> From: Tetsuo Handa Message-ID: Date: Thu, 16 Jul 2020 00:29:00 +0900 User-Agent: Mozilla/5.0 (Windows NT 6.3; Win64; x64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20200715151220.GE2571@kadam> Content-Language: en-US X-Mailman-Approved-At: Thu, 16 Jul 2020 09:42:42 +0000 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-fbdev@vger.kernel.org, Bartlomiej Zolnierkiewicz , Greg Kroah-Hartman , syzbot , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, George Kennedy , Jiri Slaby , Dmitry Vyukov Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On 2020/07/16 0:12, Dan Carpenter wrote: > I've complained about integer overflows in fbdev for a long time... > > What I'd like to see is something like the following maybe. I don't > know how to get the vc_data in fbmem.c so it doesn't include your checks > for negative. Yes. Like I said "Thus, I consider that we need more sanity/constraints checks." at https://lore.kernel.org/lkml/b1e7dd6a-fc22-bba8-0abb-d3e779329bce@i-love.sakura.ne.jp/ , we want basic checks. That's a task for fbdev people who should be familiar with necessary constraints. Anyway, my two patches are small and low cost; can we apply these patches regardless of basic checks? _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel