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=-11.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 B47DBC433ED for ; Thu, 1 Apr 2021 06:48:01 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 2E4816108F for ; Thu, 1 Apr 2021 06:48:01 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2E4816108F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id BADFF6B0080; Thu, 1 Apr 2021 02:48:00 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id B85106B0081; Thu, 1 Apr 2021 02:48:00 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A4CCB6B0082; Thu, 1 Apr 2021 02:48:00 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0052.hostedemail.com [216.40.44.52]) by kanga.kvack.org (Postfix) with ESMTP id 852E26B0080 for ; Thu, 1 Apr 2021 02:48:00 -0400 (EDT) Received: from smtpin15.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 474F3181AF5C1 for ; Thu, 1 Apr 2021 06:48:00 +0000 (UTC) X-FDA: 77982868320.15.BBC8F07 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf11.hostedemail.com (Postfix) with ESMTP id 83A4A2000249 for ; Thu, 1 Apr 2021 06:47:58 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id 7893B60234; Thu, 1 Apr 2021 06:47:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1617259678; bh=tRF5I0Qsbg2Np5QB7V1/YuBDHKtI8bbQUe6g0xCoumM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=c/7zpxLm7znv7fkR45JOEMKw5uxJpwUq4F/1LadSRYUeUzg+JeXdLSBrBSNslKaW6 +B2BEtPIOteUleHTe6fTnZJiLZbezcW6kj/ZBLsC8Rr9+8q6RKJX33FT0wC56k6s9O +ubJqacreW3aCQbf9DQVQIyAk4GQ/VJ8Y0XP7Qjt3mIguZDNNArdE42xQ9QWXol6cM NVAak9gl1Vi2d97aRKcYS9/9uyTsOGRVPVDuRgngTZdG4JacGZK0hRJTF4faaS3aNG T1OQTF1tZBHnDNIo75OKLu4SOKKGXxC3zW3CTO0jCyF6+q8Q29KRNO0O+4jJPDPC/f QqA+/0ecsotiQ== Date: Wed, 31 Mar 2021 23:47:53 -0700 From: Nathan Chancellor To: kernel test robot Cc: Kees Cook , Greg Kroah-Hartman , kbuild-all@lists.01.org, clang-built-linux@googlegroups.com, Andrew Morton , Linux Memory Management List , "Rafael J. Wysocki" , Michal Hocko , Alexey Dobriyan , Lee Duncan , Chris Leech , Adam Nichols Subject: Re: [PATCH v3] sysfs: Unconditionally use vmalloc for buffer Message-ID: <20210401064753.6ub6dhcuu6zuhdjq@archlinux-ax161> References: <20210401022145.2019422-1-keescook@chromium.org> <202104011400.HiuLgSvb-lkp@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <202104011400.HiuLgSvb-lkp@intel.com> X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 83A4A2000249 X-Stat-Signature: rae4qcoinyjoyqd5ewbcjc44dgdpe5sp Received-SPF: none (kernel.org>: No applicable sender policy available) receiver=imf11; identity=mailfrom; envelope-from=""; helo=mail.kernel.org; client-ip=198.145.29.99 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1617259678-722876 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, Apr 01, 2021 at 02:41:37PM +0800, kernel test robot wrote: > Hi Kees, > > I love your patch! Perhaps something to improve: > > [auto build test WARNING on driver-core/driver-core-testing] > [also build test WARNING on kees/for-next/pstore v5.12-rc5 next-20210331] > [cannot apply to hnaz-linux-mm/master] > [If your patch is applied to the wrong git tree, kindly drop us a note. > And when submitting patch, we suggest to use '--base' as documented in > https://git-scm.com/docs/git-format-patch] > > url: https://github.com/0day-ci/linux/commits/Kees-Cook/sysfs-Unconditionally-use-vmalloc-for-buffer/20210401-102455 > base: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core.git d225ef6fda7ce9ff7d28764bd1cceea2d0215e8b > config: powerpc-randconfig-r001-20210401 (attached as .config) > compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project 1c268a8ff4e90a85d0e634350b1104080614cf2b) > reproduce (this is a W=1 build): > wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross > chmod +x ~/bin/make.cross > # install powerpc cross compiling tool for clang build > # apt-get install binutils-powerpc-linux-gnu > # https://github.com/0day-ci/linux/commit/c80ca56c15314908ebc1881678da3b36e007a2f4 > git remote add linux-review https://github.com/0day-ci/linux > git fetch --no-tags linux-review Kees-Cook/sysfs-Unconditionally-use-vmalloc-for-buffer/20210401-102455 > git checkout c80ca56c15314908ebc1881678da3b36e007a2f4 > # save the attached .config to linux build tree > COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=powerpc > > If you fix the issue, kindly add following tag as appropriate > Reported-by: kernel test robot > > All warnings (new ones prefixed by >>): > > >> fs/sysfs/file.c:52:14: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] > return NULL + !*ppos; > ~~~~ ^ > 1 warning generated. > Arnd addressed other warnings of this nature in this patch: https://lore.kernel.org/r/20201028151202.3074398-1-arnd@kernel.org/ which it seems never got picked up :( Cheers, Nathan > vim +52 fs/sysfs/file.c > > 35 > 36 /* > 37 * To be proactively defensive against sysfs show() handlers that do not > 38 * correctly stay within their PAGE_SIZE buffer, use the vmap area to gain > 39 * the trailing guard page which will stop linear buffer overflows. > 40 */ > 41 static void *sysfs_kf_seq_start(struct seq_file *sf, loff_t *ppos) > 42 { > 43 struct kernfs_open_file *of = sf->private; > 44 struct kernfs_node *kn = of->kn; > 45 > 46 WARN_ON_ONCE(sf->buf); > 47 sf->buf = __vmalloc(kn->attr.size, GFP_KERNEL_ACCOUNT); > 48 if (!sf->buf) > 49 return ERR_PTR(-ENOMEM); > 50 sf->size = kn->attr.size; > 51 > > 52 return NULL + !*ppos; > 53 } > 54 > > --- > 0-DAY CI Kernel Test Service, Intel Corporation > https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org