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=-11.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable 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 2B5C2C433E6 for ; Fri, 17 Jul 2020 19:08:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 095612064C for ; Fri, 17 Jul 2020 19:08:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=broadcom.com header.i=@broadcom.com header.b="dcvrHKCi" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728347AbgGQTI0 (ORCPT ); Fri, 17 Jul 2020 15:08:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59136 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728238AbgGQTI0 (ORCPT ); Fri, 17 Jul 2020 15:08:26 -0400 Received: from mail-wm1-x344.google.com (mail-wm1-x344.google.com [IPv6:2a00:1450:4864:20::344]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A0D5BC0619D3 for ; Fri, 17 Jul 2020 12:08:25 -0700 (PDT) Received: by mail-wm1-x344.google.com with SMTP id w3so18743742wmi.4 for ; Fri, 17 Jul 2020 12:08:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=broadcom.com; s=google; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-transfer-encoding:content-language; bh=Vo1PWad/RfqR/fd/AxYuedHKeK/43VW6RrtpDOaz9v8=; b=dcvrHKCi7EdXkVVflvWIzJMBuN+o9keHjn/eQMQl9puSF5R7O7DfHZLCUxp+w3PrWg RRv4HZwam1InZBLTuOrqNRz7hhCb/mni2bgXb63cAv3msuRhOVpvy4cEjaPX/8j3HViS qsgnJAxeGvco2ycqJryemyRflNwJm5df8VHLA= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-transfer-encoding :content-language; bh=Vo1PWad/RfqR/fd/AxYuedHKeK/43VW6RrtpDOaz9v8=; b=bt1thlF/lwtVn8lZqv5oxlaY/fWnX8us2GbkLboEnM41SqhrT9kMgVwg4rOlU04a0l rinwK6cb6emEPlmnXgwgkbm9YaSN2CWg48h7NCXyaYYYV8qov7LMqBHVtfai9vuM8YyE N39UXu2ePEsZ5qnZ3bXUJZExTnUda6g8fMI3rlgo3CVGdl8v/z1BlAq6sNQZ87DsLXHN B9g4ERU0pPkx6L6tR6IQgBXilwJVl+Bx0X9R2rLQQPkStSDdsoio/KSDp5FD1kpa43BE M9HDOEbfw6DsjxvHP6KIy4+nMuZbA5r2eEgaX+eCEKPy/SnPpl36/0Jn1NmTu6gQ07gf UF+A== X-Gm-Message-State: AOAM530Lw2eesUtvm64l15E08zyDwAyw7WB2zyZHGOtQfgL3Jk/umRlH VlTQkpJJhhQyKEn8a1+f4GIbqg== X-Google-Smtp-Source: ABdhPJzhdwmEm/2PwY3ttPxyPeh/Z71MNC7/SFg7UbZCAs8kktCvaWRYquORL/03TJsnWTyEaFX32Q== X-Received: by 2002:a1c:27c1:: with SMTP id n184mr11044183wmn.6.1595012904136; Fri, 17 Jul 2020 12:08:24 -0700 (PDT) Received: from [10.136.13.65] ([192.19.228.250]) by smtp.gmail.com with ESMTPSA id d132sm15237532wmd.35.2020.07.17.12.08.16 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 17 Jul 2020 12:08:23 -0700 (PDT) Subject: Re: [PATCH 01/13] firmware_loader: EFI firmware loader must handle pre-allocated buffer To: Kees Cook Cc: stable@vger.kernel.org, Mimi Zohar , Matthew Wilcox , James Morris , Luis Chamberlain , Greg Kroah-Hartman , "Rafael J. Wysocki" , Alexander Viro , Jessica Yu , Dmitry Kasatkin , "Serge E. Hallyn" , Casey Schaufler , "Eric W. Biederman" , Peter Zijlstra , Matthew Garrett , David Howells , Mauro Carvalho Chehab , Randy Dunlap , "Joel Fernandes (Google)" , KP Singh , Dave Olsthoorn , Hans de Goede , Peter Jones , Andrew Morton , Stephen Boyd , Paul Moore , Stephen Smalley , linux-security-module@vger.kernel.org, linux-integrity@vger.kernel.org, selinux@vger.kernel.org, linux-fsdevel@vger.kernel.org, kexec@lists.infradead.org, linux-kernel@vger.kernel.org References: <20200717174309.1164575-1-keescook@chromium.org> <20200717174309.1164575-2-keescook@chromium.org> From: Scott Branden Message-ID: Date: Fri, 17 Jul 2020 12:08:14 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20200717174309.1164575-2-keescook@chromium.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Sender: selinux-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: selinux@vger.kernel.org On 2020-07-17 10:42 a.m., Kees Cook wrote: > The EFI platform firmware fallback would clobber any pre-allocated > buffers. Instead, correctly refuse to reallocate when too small (as > already done in the sysfs fallback), or perform allocation normally > when needed. > > Fixes: e4c2c0ff00ec ("firmware: Add new platform fallback mechanism and firm ware_request_platform()") > Cc: stable@vger.kernel.org > Signed-off-by: Kees Cook Acked-by: Scott Branden > --- > To aid in backporting, this change is made before moving > kernel_read_file() to separate header/source files. > --- > drivers/base/firmware_loader/fallback_platform.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/drivers/base/firmware_loader/fallback_platform.c b/drivers/base/firmware_loader/fallback_platform.c > index cdd2c9a9f38a..685edb7dd05a 100644 > --- a/drivers/base/firmware_loader/fallback_platform.c > +++ b/drivers/base/firmware_loader/fallback_platform.c > @@ -25,7 +25,10 @@ int firmware_fallback_platform(struct fw_priv *fw_priv, u32 opt_flags) > if (rc) > return rc; /* rc == -ENOENT when the fw was not found */ > > - fw_priv->data = vmalloc(size); > + if (fw_priv->data && size > fw_priv->allocated_size) > + return -ENOMEM; > + if (!fw_priv->data) > + fw_priv->data = vmalloc(size); > if (!fw_priv->data) > return -ENOMEM; >