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=-3.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 7116BC33CB1 for ; Fri, 17 Jan 2020 11:53:47 +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 460E120730 for ; Fri, 17 Jan 2020 11:53:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="eD59mydv" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 460E120730 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=5nhJ2GCP1B3HshMLvWrKjEyM2bQl9j3OO23ppHEWs+0=; b=eD59mydvFS/oap rokMRjI6JqntIU8wIGmBI2AJUlTHcZtAX2EnL0C32uCr8YRG949B2ASYqQJO+b600lwtC0bAuqFkw BA/3IwwhJ4F58VIB/HgNZGprsNl0/IhNUHsywHc+XTZ95Y2GMJmv9UV+gvFjDn4NkLmG4rQ0sQdId qrsh1laW19qOvcZQI9Oz9jPKmBiIR9nGIkzcw8TogIyta9z/WX0Zt+IOhBz/X8cWK2wJIZCWkZhbN H1Dot/4IvePIIseIKtw7f1WkNH0BaQFNd4kOy5fjdmnGK5bobn5eJ/MN8Ern6zKC+Ir8n78SPypWt sgvY0tCc1Sb26x+fJ3Eg==; 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 1isQC5-0002NC-8b; Fri, 17 Jan 2020 11:53:41 +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 1isQBy-0002MZ-KF for linux-arm-kernel@lists.infradead.org; Fri, 17 Jan 2020 11:53:39 +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 2F79011D4; Fri, 17 Jan 2020 03:53:34 -0800 (PST) Received: from arrakis.emea.arm.com (arrakis.cambridge.arm.com [10.1.197.42]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 6A5DB3F6C4; Fri, 17 Jan 2020 03:53:32 -0800 (PST) Date: Fri, 17 Jan 2020 11:53:30 +0000 From: Catalin Marinas To: Amit Daniel Kachhap Subject: Re: [PATCH v3 16/16] lkdtm: arm64: test kernel pointer authentication Message-ID: <20200117115330.GH26090@arrakis.emea.arm.com> References: <1576486038-9899-1-git-send-email-amit.kachhap@arm.com> <1576486038-9899-17-git-send-email-amit.kachhap@arm.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <1576486038-9899-17-git-send-email-amit.kachhap@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200117_035335_175429_864F4B6D X-CRM114-Status: GOOD ( 14.73 ) 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: Mark Rutland , Kees Cook , Suzuki K Poulose , Ard Biesheuvel , Richard Henderson , Kristina Martsenko , James Morse , Ramana Radhakrishnan , Mark Brown , Vincenzo Frascino , Will Deacon , Dave Martin , 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 Mon, Dec 16, 2019 at 02:17:18PM +0530, Amit Daniel Kachhap wrote: > This test is specific for arm64. When in-kernel Pointer Authentication > config is enabled, the return address stored in the stack is signed. > This feature helps in ROP kind of attack. If any parameters used to > generate the pac () is modified then this will fail in > the authentication stage and will lead to abort. > > This test changes the input parameter APIA kernel keys to cause abort. > The pac computed from the new key can be same as last due to hash > collision so this is retried for few times as there is no reliable way > to compare the pacs. Even though this test may fail even after retries > but this may cause authentication failure at a later stage in earlier > function returns. > > This test can be invoked as, > echo CORRUPT_PAC > /sys/kernel/debug/provoke-crash/DIRECT > > or as below if inserted as a module, > insmod lkdtm.ko cpoint_name=DIRECT cpoint_type=CORRUPT_PAC cpoint_count=1 > > [ 13.118166] lkdtm: Performing direct entry CORRUPT_PAC > [ 13.118298] lkdtm: Clearing PAC from the return address > [ 13.118466] Unable to handle kernel paging request at virtual address bfff8000108648ec > [ 13.118626] Mem abort info: > [ 13.118666] ESR = 0x86000004 > [ 13.118866] EC = 0x21: IABT (current EL), IL = 32 bits > [ 13.118966] SET = 0, FnV = 0 > [ 13.119117] EA = 0, S1PTW = 0 > > Cc: Kees Cook > Signed-off-by: Amit Daniel Kachhap Acked-by: Catalin Marinas _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel