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=-2.1 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,URIBL_BLOCKED, 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 45D9FC433F4 for ; Wed, 19 Sep 2018 02:39:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C4150214C2 for ; Wed, 19 Sep 2018 02:39:39 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="T+J92YQo" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C4150214C2 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726986AbeISIPN (ORCPT ); Wed, 19 Sep 2018 04:15:13 -0400 Received: from mail-pf1-f193.google.com ([209.85.210.193]:35745 "EHLO mail-pf1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725817AbeISIPN (ORCPT ); Wed, 19 Sep 2018 04:15:13 -0400 Received: by mail-pf1-f193.google.com with SMTP id p12-v6so1950679pfh.2 for ; Tue, 18 Sep 2018 19:39:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to :user-agent; bh=bNeTefKUd+LxqN7vrK/zspG7NrUiLeXoyMOycJqMg8g=; b=T+J92YQoMV4Y1IxH84RRbLIFszYtIlq8TWeYzfxh7HHVPnTKm8Y200m75S5HUBzTnO Hf0VHTV+9MERtV8FeRIZ4QCO6v0cm5K06qd5uWE8tZ8UyVNwgeF7MuILriw+HJnI1Ler qd0IRxEXmGFQTYQSBord1XdUDbDGe8uC0rz4vYHlvl+b+vE8eMcFQyPHZT+Znt01r0hc NKl9j+KBuOYwlYI62knyFOoy+gAQa10ZS5CH3M8sjzIGwcYfYdLyneWoKgbDTWNv00Gn rl+yl1xfLBn1MnUI7PoPiL3OD7JvjePwlGDljdegiYYDdibLOR9yi8smvYfgm/PVuG3p Wy0w== 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:content-transfer-encoding :in-reply-to:user-agent; bh=bNeTefKUd+LxqN7vrK/zspG7NrUiLeXoyMOycJqMg8g=; b=iatfxy6L//fta4P/GAXw+woH4OgaCjiWIKYveq9wvIMoDl33D01T6S8i4ILTo/+o79 Jvg3uGpOubY50BzIMJi0oUEDLamBzLcvW3N2Dw7ayR8EvINXQhVixL8OhkwkQc2jAJ1B GayBVO30d1VZRflMVCutrxf9FiAoRXxMq7Jo6Jxr+1uHto+9O++BjCp+ZCVTmTmtLdNC 07egaL1e09K6flD/BltR6LgKFMKr5ZmgpcR8Hhqn4DC58FynLTVoj+VDnpGFqvLYbC0l jUu6E5Fte4KbZIFpD/bwOmDjnYa74mx3R0xqkh72rSmEveHb3nItSSYBEhKDtGlt7Lsv 5RrA== X-Gm-Message-State: APzg51BnhzZnTMfzfWbewIn+KA4PvmH4bcm2EulstdaGAON8qTgN04hu kZJeadzBtJO0b96RClwrkLM= X-Google-Smtp-Source: ANB0Vdbt/S682h9ccbvJzEXiyhFkgD4Zma4FYVsU35yJOgO++U2aqWIsNpUAv7N4fwVyBnm+OmWEQA== X-Received: by 2002:a62:bd4:: with SMTP id 81-v6mr33859021pfl.67.1537324776752; Tue, 18 Sep 2018 19:39:36 -0700 (PDT) Received: from localhost ([175.223.11.230]) by smtp.gmail.com with ESMTPSA id k69-v6sm22541230pgd.9.2018.09.18.19.39.34 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Tue, 18 Sep 2018 19:39:35 -0700 (PDT) Date: Wed, 19 Sep 2018 11:39:32 +0900 From: Sergey Senozhatsky To: He Zhe Cc: Sergey Senozhatsky , pmladek@suse.com, sergey.senozhatsky@gmail.com, rostedt@goodmis.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 1/2] printk: Fix panic caused by passing log_buf_len to command line Message-ID: <20180919023932.GA14090@jagdpanzerIV> References: <1537291068-443145-1-git-send-email-zhe.he@windriver.com> <20180919015030.GA423@jagdpanzerIV> <6c354803-5341-7237-9ee3-7882252c7483@windriver.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <6c354803-5341-7237-9ee3-7882252c7483@windriver.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On (09/19/18 10:27), He Zhe wrote: > On 2018年09月19日 09:50, Sergey Senozhatsky wrote: > > On (09/19/18 01:17), zhe.he@windriver.com wrote: > >> @@ -1048,7 +1048,14 @@ static void __init log_buf_len_update(unsigned size) > >> /* save requested log_buf_len since it's too early to process it */ > >> static int __init log_buf_len_setup(char *str) > >> { > >> - unsigned size = memparse(str, &str); > >> + unsigned size; > > unsigned int size; > > This is in v1 but then Steven suggested that it should be split out > and only keep the pure fix part here. Ah, I see. Hmm... memparse() returns u64 value. A user *probably* can ask the kernel to allocate log_buf larger than 'unsigned int'. So may be I'd do two fixes here: First - switch to u64 size. Second - check for NULL str. Steven, Petr, what do you think? -ss