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=-6.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 A689CC43463 for ; Fri, 18 Sep 2020 21:35:33 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id BD91320663 for ; Fri, 18 Sep 2020 21:35:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="Qm/FmtT5" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BD91320663 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=chromium.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-19952-kernel-hardening=archiver.kernel.org@lists.openwall.com Received: (qmail 24329 invoked by uid 550); 18 Sep 2020 21:35:26 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Received: (qmail 24306 invoked from network); 18 Sep 2020 21:35:26 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=OsXO9Vng0uZ8zdPlCQEPUkvMN685QAvewZuZv3id6Vk=; b=Qm/FmtT5Dnyrxf4BCgQpgqbDw7sS/zTtWsVgCPYD/Z8fGcfQ5xbRlGReuouD+SHCd9 dZJK4vmeSlLB9LbvCFrufdgXKAOEcR0Sj+Z6M4GjiMmOMsAqZazgwvwTj14O7ZQgEo98 fFyktTytinUg2oHTwmTXsDyGhM3irl/3gs0Oc= 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:in-reply-to; bh=OsXO9Vng0uZ8zdPlCQEPUkvMN685QAvewZuZv3id6Vk=; b=lusUni+qkZ3AmodEA3Cq9ON2htGjmEzzZofulV0L/c2SUm9pKVoaxt7dnSniC7LKlR /dKcasizsHYmHiJS/NIAWa8QR10IkjNnYiDmnwmyFwVmbdIZ2+UJVZ7cZXwj6UlG1uC6 iku9KixJDldn55WFJkMwYTFINkNXj5HK8u6tFtNBx+kaEJZlSKCOrD99XVFb5fXsPgyT ua4VIyKL7xoQ8JfyRZ/khNdGDdX05dTL49Df3JZqxXbFvKdz1Cng3iH1pLyepNJZMFBt kgY471gyx3Yc43EjIZlC8OikcYJSMfKa9kzyXv52lYV+o3GrYZyVtxGH2L4DMOZhDXUv 5StQ== X-Gm-Message-State: AOAM533j30oXz6iAgFlh51rpNRoBznD4M/FlONtTq4jMHgUgDlfHeAmc F4zUdh7sCktEuYc9AWoajDN82Q== X-Google-Smtp-Source: ABdhPJyK4NrndRd3u8+tWx5b+nRCti5n/xaxbJJsCKhy+21AIJjWUWUQo+BNLBjVu3tDwrR5itradw== X-Received: by 2002:a17:90a:156:: with SMTP id z22mr14965929pje.140.1600464914535; Fri, 18 Sep 2020 14:35:14 -0700 (PDT) Date: Fri, 18 Sep 2020 14:35:12 -0700 From: Kees Cook To: John Wood Cc: kernel-hardening@lists.openwall.com, Jann Horn , Matthew Wilcox , Jonathan Corbet , Alexander Viro , Ingo Molnar , Peter Zijlstra , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Luis Chamberlain , Iurii Zaikin , James Morris , "Serge E. Hallyn" , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-security-module@vger.kernel.org Subject: Re: [RFC PATCH 6/6] security/fbfam: Mitigate a fork brute force attack Message-ID: <202009181433.EAF237C36@keescook> References: <20200910202107.3799376-1-keescook@chromium.org> <20200910202107.3799376-7-keescook@chromium.org> <202009101649.2A0BF95@keescook> <20200918152116.GB3229@ubuntu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200918152116.GB3229@ubuntu> On Fri, Sep 18, 2020 at 06:02:16PM +0200, John Wood wrote: > On Thu, Sep 10, 2020 at 04:56:19PM -0700, Kees Cook wrote: > > On Thu, Sep 10, 2020 at 01:21:07PM -0700, Kees Cook wrote: > > > + pr_warn("fbfam: Offending process with PID %d killed\n", > > > + p->pid); > > > > I'd make this ratelimited (along with Jann's suggestions). > > Sorry, but I don't understand what you mean with "make this ratelimited". > A clarification would be greatly appreciated. Ah! Yes, sorry for not being more clear. There are ratelimit helpers for the pr_*() family of functions, e.g.: pr_warn_ratelimited("brute: Offending process with PID... -- Kees Cook