From patchwork Thu Jun 6 16:48:44 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexander Potapenko X-Patchwork-Id: 10981073 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 6D31892A for ; Fri, 7 Jun 2019 08:55:45 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5C50528956 for ; Fri, 7 Jun 2019 08:55:45 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 4FBDC28A03; Fri, 7 Jun 2019 08:55:45 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.5 required=2.0 tests=BAYES_00,DATE_IN_PAST_12_24, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,RCVD_IN_DNSWL_HI,USER_IN_DEF_DKIM_WL autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C900228956 for ; Fri, 7 Jun 2019 08:55:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726880AbfFGIzo (ORCPT ); Fri, 7 Jun 2019 04:55:44 -0400 Received: from mail-vk1-f201.google.com ([209.85.221.201]:56462 "EHLO mail-vk1-f201.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726531AbfFGIzo (ORCPT ); Fri, 7 Jun 2019 04:55:44 -0400 Received: by mail-vk1-f201.google.com with SMTP id a4so514339vki.23 for ; Fri, 07 Jun 2019 01:55:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=7sAcFhzm9//uuWPzvmk6JGPNvQAtroDUafFgbzLm/yQ=; b=rdCdjwMg3gY0shibBU1Y00zUYQIbtOM1x+c+yT+bFe7iBq5B+DoGdkjBVtzSVU+VH4 pP96pPCG+Y973PP3O/lWES1n/UCOKtZa3RNHsidIfwLMPCrenvyWFxRyRqzXyZsOsCjr qSODaba6lZJocr0BUenu+4ZEbh1HblpWCFTpj73QuxvyUjbyJLZFozdmYeqn4HCfWCGh /AMfOsdrVXar7zg8+8htj5UxeyZr5izHf4MgEsCAHA6hwcqCH0BBWjwFe+k9QgjrSEmp U+n4drC9Dr/6Kek1dfT2CT1N1chYQ3TylncKuorf8JsVOifT/sDp1sYcXeCWD0MPL07+ 5kBg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=7sAcFhzm9//uuWPzvmk6JGPNvQAtroDUafFgbzLm/yQ=; b=KxHmUddiL1xSGvjTzY4dogHe9S+XIjGMuDImV0erov3vy+/1UI/ge7oxpQNB8NqMim L0adyb/BXsHvOM7uSwNdGxAg4EIT4ZmAsRVlksYFhHLzA6fZaUf262zxkeXktdydknrs Nk+v7l1OSW0kAdj3oPmGPUmSQOmbU4pW9bvyO6fHYog9b0zh0LVY0xmNqta6b0E0yvqI xwiaILhtS9t6MQSRg4K0hm4DE6AsTecizWEp1JyMMVjc7GC8HfMJOwDWzlb8APJkVGpo mC3FMnvlnEpRJRh6NcaA3AuLG3TvfH9+Po+cZuGIHIeJDV6A/sO2quYhVEzM8NyaZ3lk ot7A== X-Gm-Message-State: APjAAAUAshQoWyWFBj3rKPl8g6MzvVUjluh6Q58lppJIOByQQbvCFgPl UMo//rsVztqQwvolhxeiPLNky0i1eeE= X-Google-Smtp-Source: APXvYqxl2fR/kTIk2qghgxJ9BB+AYD6tf6ZHiB+nSiWLpCvBpXZOF6k/lSrBGI83j05i6uqHwLil+lUnGI4= X-Received: by 2002:a1f:e906:: with SMTP id g6mr514895vkh.25.1559897742846; Fri, 07 Jun 2019 01:55:42 -0700 (PDT) Date: Thu, 6 Jun 2019 18:48:44 +0200 In-Reply-To: <20190606164845.179427-1-glider@google.com> Message-Id: <20190606164845.179427-3-glider@google.com> Mime-Version: 1.0 References: <20190606164845.179427-1-glider@google.com> X-Mailer: git-send-email 2.22.0.rc1.311.g5d7573a151-goog Subject: [PATCH v6 2/3] mm: init: report memory auto-initialization features at boot time From: Alexander Potapenko To: Andrew Morton , Christoph Lameter Cc: Alexander Potapenko , Kees Cook , Dmitry Vyukov , James Morris , Jann Horn , Kostya Serebryany , Laura Abbott , Mark Rutland , Masahiro Yamada , Matthew Wilcox , Nick Desaulniers , Randy Dunlap , Sandeep Patil , "Serge E. Hallyn" , Souptick Joarder , Marco Elver , Kaiwan N Billimoria , kernel-hardening@lists.openwall.com, linux-mm@kvack.org, linux-security-module@vger.kernel.org Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: X-Virus-Scanned: ClamAV using ClamSMTP Print the currently enabled stack and heap initialization modes. Stack initialization is enabled by a config flag, while heap initialization is configured at boot time with defaults being set in the config. It's more convenient for the user to have all information about these hardening measures in one place. The possible options for stack are: - "all" for CONFIG_INIT_STACK_ALL; - "byref_all" for CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF_ALL; - "byref" for CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF; - "__user" for CONFIG_GCC_PLUGIN_STRUCTLEAK_USER; - "off" otherwise. Depending on the values of init_on_alloc and init_on_free boottime options we also report "heap alloc" and "heap free" as "on"/"off". In the init_on_free mode initializing pages at boot time may take some time, so print a notice about that as well. Signed-off-by: Alexander Potapenko Suggested-by: Kees Cook To: Andrew Morton To: Christoph Lameter Cc: Dmitry Vyukov Cc: James Morris Cc: Jann Horn Cc: Kostya Serebryany Cc: Laura Abbott Cc: Mark Rutland Cc: Masahiro Yamada Cc: Matthew Wilcox Cc: Nick Desaulniers Cc: Randy Dunlap Cc: Sandeep Patil Cc: "Serge E. Hallyn" Cc: Souptick Joarder Cc: Marco Elver Cc: Kaiwan N Billimoria Cc: kernel-hardening@lists.openwall.com Cc: linux-mm@kvack.org Cc: linux-security-module@vger.kernel.org Acked-by: Kees Cook --- v6: - update patch description, fixed message about clearing memory --- init/main.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/init/main.c b/init/main.c index 66a196c5e4c3..e68ef1f181f9 100644 --- a/init/main.c +++ b/init/main.c @@ -520,6 +520,29 @@ static inline void initcall_debug_enable(void) } #endif +/* Report memory auto-initialization states for this boot. */ +void __init report_meminit(void) +{ + const char *stack; + + if (IS_ENABLED(CONFIG_INIT_STACK_ALL)) + stack = "all"; + else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF_ALL)) + stack = "byref_all"; + else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF)) + stack = "byref"; + else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_USER)) + stack = "__user"; + else + stack = "off"; + + pr_info("mem auto-init: stack:%s, heap alloc:%s, heap free:%s\n", + stack, want_init_on_alloc(GFP_KERNEL) ? "on" : "off", + want_init_on_free() ? "on" : "off"); + if (want_init_on_free()) + pr_info("mem auto-init: clearing system memory may take some time...\n"); +} + /* * Set up kernel memory allocators */ @@ -530,6 +553,7 @@ static void __init mm_init(void) * bigger than MAX_ORDER unless SPARSEMEM. */ page_ext_init_flatmem(); + report_meminit(); mem_init(); kmem_cache_init(); pgtable_init();