From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from dpdk.org (dpdk.org [92.243.14.124]) by inbox.dpdk.org (Postfix) with ESMTP id D338EA00E6 for ; Thu, 11 Jul 2019 15:14:21 +0200 (CEST) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 01F3E322C; Thu, 11 Jul 2019 15:14:21 +0200 (CEST) Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by dpdk.org (Postfix) with ESMTP id C00711D9E; Thu, 11 Jul 2019 15:14:18 +0200 (CEST) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga006.jf.intel.com ([10.7.209.51]) by orsmga103.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 11 Jul 2019 06:14:17 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.63,478,1557212400"; d="scan'208";a="171226189" Received: from aburakov-mobl1.ger.corp.intel.com (HELO [10.237.220.82]) ([10.237.220.82]) by orsmga006.jf.intel.com with ESMTP; 11 Jul 2019 06:14:15 -0700 To: Yasufumi Ogawa , david.marchand@redhat.com Cc: dev@dpdk.org, stable@dpdk.org, Yasufumi Ogawa References: <1555379952-23517-1-git-send-email-ogawa.yasufumi@lab.ntt.co.jp> <20190711103148.9187-1-yasufum.o@gmail.com> <20190711103148.9187-2-yasufum.o@gmail.com> From: "Burakov, Anatoly" Message-ID: Date: Thu, 11 Jul 2019 14:14:15 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.7.2 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Subject: Re: [dpdk-dev] [PATCH v3 1/1] fbarray: get fbarrays from containerized secondary X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" On 11-Jul-19 12:57 PM, Yasufumi Ogawa wrote: > On 2019/07/11 19:53, Burakov, Anatoly wrote: >> On 11-Jul-19 11:31 AM, yasufum.o@gmail.com wrote: >>> From: Yasufumi Ogawa >>> >> <...> >> >>> +    if (getpid() == 1) { >>> +        FILE *hn_fp; >>> +        hn_fp = fopen("/etc/hostname", "r"); >>> +        if (hn_fp == NULL) { >>> +            RTE_LOG(ERR, EAL, >>> +                "Cannot open '/etc/hostname' for secondary\n"); >>> +            return -1; >>> +        } >>> + >>> +        /* with docker, /etc/hostname just has one entry of hostname */ >>> +        if (fscanf(hn_fp, "%s", proc_id) == EOF) { >> >> Apologies for not pointing this out earlier, but do i understand >> correctly that there's no bounds checking here, and fscanf() will >> write however many bytes it wants? > I understand "%s" is not appropriate. hostname is 12 bytes char and I > thought proc_id[16] is enough, but it is unsafe. In addition, hostname > can be defined by user with docker's option, so it should be enough for > user defined name. > > How do you think expecting max 32 chars of hostname and set boundary > "%32s" as following? > >     proc_id[33];  /* define proc id from hostname less than 33 bytes. */ >     ... >     if (fscanf(hn_fp, "%32s", proc_id) == EOF) { > As long as it takes NULL-termination into account as well, it should be OK. I can't recall off the top of my head if %32s includes NULL terminator (probably not?). -- Thanks, Anatoly