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=-13.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,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 26F7FC10F27 for ; Mon, 9 Mar 2020 12:17:28 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id EB471205ED for ; Mon, 9 Mar 2020 12:17:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="Drn8bMft" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EB471205ED Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=GX1ImonsKBG4EYGrLlpgco9NWtWI5s5ofVlkImCjQWE=; b=Drn8bMftVC184r fnCaKQ7oJn395Y3d7yJ+kHUEGaRIx/ItOjO3SWIzSnaAxVWvun+A7Nvb2VttMx2B35eBCGsIlGwG3 dVXRZ8afmIIrrO6uwssVSAC9c6OylTOKYhPbZ9vlPiaLC+MuT2V/KoTNLawyFLSa0KWfnXTo/3Lx/ ecp9G8QZH4F4mAW3gfsFqHKbCFbs6CLVpTA/K1bb96xKspvSgST+m+Pdqg8qN9pKHAFr/m6O0Ktx9 FiMyNzRuHqnIKk0aaoPpzKOVVv69DcKP3BaWue8fjrGOGVyc2h7e3CMvmisl0k6/GOy4aI8jGgX94 rfWKj8xVKbqEs1NH7hrg==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jBHLY-0000Cf-Ny; Mon, 09 Mar 2020 12:17:24 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jBHLW-0000C6-7r for linux-arm-kernel@lists.infradead.org; Mon, 09 Mar 2020 12:17:23 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id B9EC030E; Mon, 9 Mar 2020 05:17:20 -0700 (PDT) Received: from lakrids.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 19ABF3F6CF; Mon, 9 Mar 2020 05:17:18 -0700 (PDT) Date: Mon, 9 Mar 2020 12:17:14 +0000 From: Mark Rutland To: Phong Tran Subject: Re: [PATCH] arm64: add check_wx_pages debugfs for CHECK_WX Message-ID: <20200309121713.GA26309@lakrids.cambridge.arm.com> References: <20200307093926.27145-1-tranmanphong@gmail.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200307093926.27145-1-tranmanphong@gmail.com> User-Agent: Mutt/1.11.1+11 (2f07cb52) (2018-12-01) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200309_051722_372022_F2574B7A X-CRM114-Status: GOOD ( 19.39 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: keescook@chromium.org, steve.capper@arm.com, catalin.marinas@arm.com, kernel-hardening@lists.openwall.com, linux-kernel@vger.kernel.org, steven.price@arm.com, alexios.zavras@intel.com, broonie@kernel.org, tglx@linutronix.de, will@kernel.org, akpm@linux-foundation.org, linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Sat, Mar 07, 2020 at 04:39:26PM +0700, Phong Tran wrote: > follow the suggestion from > https://github.com/KSPP/linux/issues/35 That says: | This should be implemented for all architectures ... so surely this should be in generic code, rahter than being arm64-specific? Thanks, Mark. > > 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 > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel