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=-2.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT 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 28A6EC43381 for ; Tue, 19 Feb 2019 12:51:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EA0BF204EC for ; Tue, 19 Feb 2019 12:51:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="J3p5FTkR" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728497AbfBSMvV (ORCPT ); Tue, 19 Feb 2019 07:51:21 -0500 Received: from mail-pl1-f193.google.com ([209.85.214.193]:45045 "EHLO mail-pl1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726847AbfBSMvU (ORCPT ); Tue, 19 Feb 2019 07:51:20 -0500 Received: by mail-pl1-f193.google.com with SMTP id c4so5374897pls.11 for ; Tue, 19 Feb 2019 04:51:20 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:date:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=YLJGGyw1ORKNIxDzpGH3jaJrr4hlEb1GdSZgwab9IMQ=; b=J3p5FTkRPx5k3vWXcaE2DQjD9+0XI8sPoJ8kmZc1MjGtFvdDX3SUXshVlTk10hJPjS EfV096wwIsLUqfc+yVHWLGgYJzl9Hf5IaAMQ8S5PojxX+ekvnvMpArWbDSLPdFa3x0vq PZ9LRESzCxKgK4TjqVxN2G2LkBoltx6zFbf7INGD0o9Aw6/RYKsbu4PJM49yNH1pE4ZY jqiAL0aDZ0fETTGuD8NjWBl5sVdMpcCI1Ot8xmNprfdE313VPuJ/+PbOv9HtAHmK1rpM MJ7GjRb0q2RA+pOk9EmboDHIwGnbVxLQ/AxGbnhe6d62Jh44NGLegq27cXDMKpiULGV8 UiAw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:date:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=YLJGGyw1ORKNIxDzpGH3jaJrr4hlEb1GdSZgwab9IMQ=; b=iA/DAdiVHS+TOCRZKLko0hZGG3KbqHB7G53W6TvP8VK1eQI43bKLP6YvjuDCY6bybd Ux8/o4PWL0OeX9qPSQ0a0cFqZp1qxWDHPUXJiCQr9d8yKQ/NBUxjaLlAtOARL8+nuENx Gyg5BzTzQOxR4cdNE9gWBEclb+OgOprf+UKIlNzbGX1hMO80a5MfG/kl3IbhKVH2uW4o cv+WatrS2CErjfIXb7zDWQCBEzaX4O4a7l2SZyLg43hYgu+fAe8qyUQNRIbCMmIcS5HT oXzq0ewnieD1XOWpHNfQvVKMXaQKrn/zrckFgkvX9ojyqhzDd70Pxz9ymHy5QKWX1+fW gB7A== X-Gm-Message-State: AHQUAubtcK9guZ4GNQreAd7bi0s2ULDsbuwtalFNAXpQgnyVn5pLLT1/ 7atXE1vSGv9zpNaTC0N8FVA= X-Google-Smtp-Source: AHgI3IbYZ8RvAWcr9gVEqtVXARLnBq5KSuAP70g3+6heBIzfDCJflRQMOS2Nf3xLcRbWgtyXJx2heQ== X-Received: by 2002:a17:902:7586:: with SMTP id j6mr14706120pll.259.1550580680185; Tue, 19 Feb 2019 04:51:20 -0800 (PST) Received: from localhost ([121.137.63.184]) by smtp.gmail.com with ESMTPSA id u186sm23735615pfu.51.2019.02.19.04.51.18 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Tue, 19 Feb 2019 04:51:19 -0800 (PST) From: Sergey Senozhatsky X-Google-Original-From: Sergey Senozhatsky Date: Tue, 19 Feb 2019 21:51:15 +0900 To: Andy Shevchenko Cc: Sergey Senozhatsky , Petr Mladek , Andy Shevchenko , Rasmus Villemoes , Linus Torvalds , "Tobin C . Harding" , Joe Perches , Andrew Morton , Michal Hocko , Sergey Senozhatsky , Steven Rostedt , Linux Kernel Mailing List Subject: Re: [PATCH v6 8/9] vsprintf: Prevent crash when dereferencing invalid pointers Message-ID: <20190219125115.GA19910@tigerII.localdomain> References: <20190208152310.29531-1-pmladek@suse.com> <20190208152310.29531-9-pmladek@suse.com> <20190219033003.GA2284@jagdpanzerIV> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.11.3 (2019-02-01) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On (02/19/19 13:02), Andy Shevchenko wrote: [..] > And if it's not? You will get in either case incomplete information, > but at least with "(e" (or even "(") you might get a clue that it > errornous conditions. The thing I'm signaling here is that in some cases we still can crash the kernel; with the difference that invalid dereference can now be a memory corruption. Just saying. -ss