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=-14.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 CC3AAC10F00 for ; Sat, 7 Mar 2020 09:39:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A26582070A for ; Sat, 7 Mar 2020 09:39:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="S/Ump+m7" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726267AbgCGJjm (ORCPT ); Sat, 7 Mar 2020 04:39:42 -0500 Received: from mail-pg1-f196.google.com ([209.85.215.196]:42913 "EHLO mail-pg1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725909AbgCGJjm (ORCPT ); Sat, 7 Mar 2020 04:39:42 -0500 Received: by mail-pg1-f196.google.com with SMTP id h8so2274016pgs.9 for ; Sat, 07 Mar 2020 01:39:41 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=TQrEvZ13F8kEvhfqqpGuqFY2wEN2DIfUxspJmPRPnIo=; b=S/Ump+m7pX1/2CQ88Se755gIiG6OFrXK2l/vah7aFG/d2RAfEoB7TE8hjfGUTil34U yOaTgDLAAka5xml/5Pud4/O/GJ4N43tPXekh3oTC0Ip5ViOMJHy5GwRKliFKleSrNjt5 CntuBDxL66X6Tt4URFw7EACYFPbil8BU9wlYdCaH/uXNYaDvqi624jOc9Un1jcgUEi3p MNa45X3SwRRzhlZoAhG5vXImE/Yy7RrqiZw18wVv0XwDZ17L+OjYm4JBQmXEmeD2mfXp CcoGiIiEnVw6N4a3/flDIX+mJwATmetu4O3tOBszVqf/yyvFawLFMIaIn+CEIlN8y7V+ ugXw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=TQrEvZ13F8kEvhfqqpGuqFY2wEN2DIfUxspJmPRPnIo=; b=KTXmHMjl7t0dZBKpYZRDp/Di45HQhV/osG11vyKE0y0Qk0PKqQwA4/RDzD5polyYdl c7y1ttSMtZimX6W5bqE9b+N5gDXVZa9pOEG6zPZPz09FCXtOPHU0qJfAmvlJJhSrkt8E TMelJmbWXN4noYuq9BA5V/Mcr1bOm34resflf+N2eHT9p6FrIu1xha70KcpZMmltE2Ax 7R+M4ZmNH+IPv1C5kzoqTv/egLkk7fEOS7Xwu2k/iS6YbL3T+UG3y6u3zEh0buWvODTj mHzw+98AAMosWzd2Jc9OrH68Hr9tk/NHK6AuGB6Ca6C0MQvqIlmAZF0HsP1cLYzcRZ86 rWLg== X-Gm-Message-State: ANhLgQ1YbO4cbjhsfH0qbba8dKnUDQ2CRcF6Bd2M98gCmmuAV3NRb1zr KM7ATIKVLw28cQqrcSBWmiw= X-Google-Smtp-Source: ADFU+vsMj19AZ1LMNkk/TpNkNt56C7jYnDIJMIFA0yMpCIVVFSYlfPbfxqUpAEoPlL07hhQWMJ5ofg== X-Received: by 2002:a63:348b:: with SMTP id b133mr7346984pga.372.1583573980485; Sat, 07 Mar 2020 01:39:40 -0800 (PST) Received: from debian.net.fpt ([2405:4800:58f7:2133:c967:474d:b56a:15e9]) by smtp.gmail.com with ESMTPSA id q13sm37932689pgh.30.2020.03.07.01.39.36 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 07 Mar 2020 01:39:39 -0800 (PST) From: Phong Tran To: catalin.marinas@arm.com, will@kernel.org, alexios.zavras@intel.com, tglx@linutronix.de, akpm@linux-foundation.org, steven.price@arm.com, steve.capper@arm.com, mark.rutland@arm.com, broonie@kernel.org, keescook@chromium.org Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, kernel-hardening@lists.openwall.com, Phong Tran Subject: [PATCH] arm64: add check_wx_pages debugfs for CHECK_WX Date: Sat, 7 Mar 2020 16:39:26 +0700 Message-Id: <20200307093926.27145-1-tranmanphong@gmail.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org follow the suggestion from https://github.com/KSPP/linux/issues/35 Signed-off-by: Phong Tran --- arch/arm64/Kconfig.debug | 3 ++- arch/arm64/include/asm/ptdump.h | 2 ++ arch/arm64/mm/dump.c | 1 + arch/arm64/mm/ptdump_debugfs.c | 18 ++++++++++++++++++ 4 files changed, 23 insertions(+), 1 deletion(-) diff --git a/arch/arm64/Kconfig.debug b/arch/arm64/Kconfig.debug index 1c906d932d6b..be552fa351e2 100644 --- a/arch/arm64/Kconfig.debug +++ b/arch/arm64/Kconfig.debug @@ -48,7 +48,8 @@ config DEBUG_WX of other unfixed kernel bugs easier. There is no runtime or memory usage effect of this option - once the kernel has booted up - it's a one time check. + once the kernel has booted up - it's a one time check and + can be checked by echo "1" to "check_wx_pages" debugfs in runtime. If in doubt, say "Y". diff --git a/arch/arm64/include/asm/ptdump.h b/arch/arm64/include/asm/ptdump.h index 38187f74e089..b80d6b4fc508 100644 --- a/arch/arm64/include/asm/ptdump.h +++ b/arch/arm64/include/asm/ptdump.h @@ -24,9 +24,11 @@ struct ptdump_info { void ptdump_walk(struct seq_file *s, struct ptdump_info *info); #ifdef CONFIG_PTDUMP_DEBUGFS void ptdump_debugfs_register(struct ptdump_info *info, const char *name); +int ptdump_check_wx_init(void); #else static inline void ptdump_debugfs_register(struct ptdump_info *info, const char *name) { } +static inline int ptdump_check_wx_init(void) { return 0; } #endif void ptdump_check_wx(void); #endif /* CONFIG_PTDUMP_CORE */ diff --git a/arch/arm64/mm/dump.c b/arch/arm64/mm/dump.c index 860c00ec8bd3..60c99a047763 100644 --- a/arch/arm64/mm/dump.c +++ b/arch/arm64/mm/dump.c @@ -378,6 +378,7 @@ static int ptdump_init(void) #endif ptdump_initialize(); ptdump_debugfs_register(&kernel_ptdump_info, "kernel_page_tables"); + ptdump_check_wx_init(); return 0; } device_initcall(ptdump_init); diff --git a/arch/arm64/mm/ptdump_debugfs.c b/arch/arm64/mm/ptdump_debugfs.c index 1f2eae3e988b..73cddc12c3c2 100644 --- a/arch/arm64/mm/ptdump_debugfs.c +++ b/arch/arm64/mm/ptdump_debugfs.c @@ -16,3 +16,21 @@ void ptdump_debugfs_register(struct ptdump_info *info, const char *name) { debugfs_create_file(name, 0400, NULL, info, &ptdump_fops); } + +static int check_wx_debugfs_set(void *data, u64 val) +{ + if (val != 1ULL) + return -EINVAL; + + ptdump_check_wx(); + + return 0; +} + +DEFINE_SIMPLE_ATTRIBUTE(check_wx_fops, NULL, check_wx_debugfs_set, "%llu\n"); + +int ptdump_check_wx_init(void) +{ + return debugfs_create_file("check_wx_pages", 0200, NULL, + NULL, &check_wx_fops) ? 0 : -ENOMEM; +} -- 2.20.1