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=-20.6 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL 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 82C92C433E3 for ; Tue, 21 Jul 2020 09:45:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4FA5C20771 for ; Tue, 21 Jul 2020 09:45:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="i7S9t2tE" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728907AbgGUJpC (ORCPT ); Tue, 21 Jul 2020 05:45:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38408 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725984AbgGUJpB (ORCPT ); Tue, 21 Jul 2020 05:45:01 -0400 Received: from mail-wr1-x444.google.com (mail-wr1-x444.google.com [IPv6:2a00:1450:4864:20::444]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 133B7C061794 for ; Tue, 21 Jul 2020 02:45:01 -0700 (PDT) Received: by mail-wr1-x444.google.com with SMTP id z2so20574255wrp.2 for ; Tue, 21 Jul 2020 02:45:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=VCTmXoCDoueHGgkSs0dR8Q0gxBgF8BRtzs8whbeoPBY=; b=i7S9t2tE6o1ZpRYbBoPLh0mSIFrwHpF9lRxApXBd0SVtfEaMYvKF999IuDfaCE0DdV wFP+lVdRe3oBxP2XXvkxkBId3a9rt+6LPKWVsl+ePCY53KV/eftUkC17hvcyirlr+CGK x7ecwNpbckzsh0wui6eblLsfMr8GEq9ZrWF10CjkBxj2vMY7btc6zTVBhf2gFaf+aYKQ Z9o0w00u6PzL/RWmFmEzV0p9EKWUu+yEx7/TbdTY8Td8Japa4BSiSwPQ6XbmtKjsTrTi vXBWkcRXULUnuwkT7FCat/ZEFHAvwe0oSFvoHGLxUv4FYZhSJU1tk0eMqjkihc349oCz jYCg== 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:in-reply-to :references:mime-version:content-transfer-encoding; bh=VCTmXoCDoueHGgkSs0dR8Q0gxBgF8BRtzs8whbeoPBY=; b=gpmFJ4ffkpeG+HEZybcOsGJfIDzW09VBp5B+EmyGJ93jZDlICJ/fIPz47IquqL9HVc 98HuBmJM/t8XMNiiuYY0hJrYkFus85lNgtFm4bI9YzauAy2XhViy4uEBZ0DDzCQy1uOb teq5pgU/p+Uhyd762c8QvFConZofstZ69wBjR/xD16RVWomVxS739cMOr4gGZBhNhmWY EihvNOY8G8SKkVmYubfs8ZOXFAY/bdG6qiVpJk7ig3LkuCSjyVMC+3JNS7cw3siV8mvI 5/6pLK0Ha6Ko8yx4M/VgP1kmdjpO26D8UIZ4lSYZ3C6iWbI0fRKbwtSkAK8YdJOy0cYJ NQ6w== X-Gm-Message-State: AOAM530GUyX5SFykr7mfGEwtj2Uqd9E428u6MSvIDosNmlxkW6673jHC R3t3qEBk2pB6koLySUizFwWNyQ== X-Google-Smtp-Source: ABdhPJwsEeqkTbsLPEJadyPaueujiKzL/IxGYymb0jshDg7vVUsqj2qjWEo9k1RSpX4pHM494OqVlA== X-Received: by 2002:adf:f542:: with SMTP id j2mr25975490wrp.61.1595324699596; Tue, 21 Jul 2020 02:44:59 -0700 (PDT) Received: from localhost ([2a01:4b00:8523:2d03:cd93:4ca4:af31:19e5]) by smtp.gmail.com with ESMTPSA id l1sm39195773wrb.12.2020.07.21.02.44.58 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 21 Jul 2020 02:44:58 -0700 (PDT) From: David Brazdil To: Marc Zyngier , Will Deacon , Catalin Marinas , James Morse , Julien Thierry , Suzuki K Poulose Cc: kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, android-kvm@google.com, kernel-team@android.com, David Brazdil Subject: [PATCH 1/2] KVM: arm64: Make nVHE ASLR conditional on RANDOMIZE_BASE Date: Tue, 21 Jul 2020 10:44:44 +0100 Message-Id: <20200721094445.82184-2-dbrazdil@google.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200721094445.82184-1-dbrazdil@google.com> References: <20200721094445.82184-1-dbrazdil@google.com> 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 If there are spare bits in non-VHE hyp VA, KVM unconditionally replaces them with a random tag chosen at init. Disable this if the kernel is built without RANDOMIZE_BASE to align with kernel behavior. Signed-off-by: David Brazdil --- arch/arm64/kvm/va_layout.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm64/kvm/va_layout.c b/arch/arm64/kvm/va_layout.c index a4f48c1ac28c..e0404bcab019 100644 --- a/arch/arm64/kvm/va_layout.c +++ b/arch/arm64/kvm/va_layout.c @@ -48,7 +48,7 @@ __init void kvm_compute_layout(void) va_mask = GENMASK_ULL(tag_lsb - 1, 0); tag_val = hyp_va_msb; - if (tag_lsb != (vabits_actual - 1)) { + if (IS_ENABLED(CONFIG_RANDOMIZE_BASE) && tag_lsb != (vabits_actual - 1)) { /* We have some free bits to insert a random tag. */ tag_val |= get_random_long() & GENMASK_ULL(vabits_actual - 2, tag_lsb); } -- 2.27.0 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=-12.8 required=3.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED,DKIM_INVALID,DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT 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 95C48C433DF for ; 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Tue, 21 Jul 2020 02:44:59 -0700 (PDT) Received: from localhost ([2a01:4b00:8523:2d03:cd93:4ca4:af31:19e5]) by smtp.gmail.com with ESMTPSA id l1sm39195773wrb.12.2020.07.21.02.44.58 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 21 Jul 2020 02:44:58 -0700 (PDT) From: David Brazdil To: Marc Zyngier , Will Deacon , Catalin Marinas , James Morse , Julien Thierry , Suzuki K Poulose Subject: [PATCH 1/2] KVM: arm64: Make nVHE ASLR conditional on RANDOMIZE_BASE Date: Tue, 21 Jul 2020 10:44:44 +0100 Message-Id: <20200721094445.82184-2-dbrazdil@google.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200721094445.82184-1-dbrazdil@google.com> References: <20200721094445.82184-1-dbrazdil@google.com> MIME-Version: 1.0 Cc: android-kvm@google.com, linux-kernel@vger.kernel.org, kernel-team@android.com, kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org X-BeenThere: kvmarm@lists.cs.columbia.edu X-Mailman-Version: 2.1.14 Precedence: list List-Id: Where KVM/ARM decisions are made List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu If there are spare bits in non-VHE hyp VA, KVM unconditionally replaces them with a random tag chosen at init. Disable this if the kernel is built without RANDOMIZE_BASE to align with kernel behavior. Signed-off-by: David Brazdil --- arch/arm64/kvm/va_layout.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm64/kvm/va_layout.c b/arch/arm64/kvm/va_layout.c index a4f48c1ac28c..e0404bcab019 100644 --- a/arch/arm64/kvm/va_layout.c +++ b/arch/arm64/kvm/va_layout.c @@ -48,7 +48,7 @@ __init void kvm_compute_layout(void) va_mask = GENMASK_ULL(tag_lsb - 1, 0); tag_val = hyp_va_msb; - if (tag_lsb != (vabits_actual - 1)) { + if (IS_ENABLED(CONFIG_RANDOMIZE_BASE) && tag_lsb != (vabits_actual - 1)) { /* We have some free bits to insert a random tag. */ tag_val |= get_random_long() & GENMASK_ULL(vabits_actual - 2, tag_lsb); } -- 2.27.0 _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm 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=-13.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_ADSP_CUSTOM_MED,DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT 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 197F7C433E2 for ; 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Tue, 21 Jul 2020 02:44:59 -0700 (PDT) Received: from localhost ([2a01:4b00:8523:2d03:cd93:4ca4:af31:19e5]) by smtp.gmail.com with ESMTPSA id l1sm39195773wrb.12.2020.07.21.02.44.58 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 21 Jul 2020 02:44:58 -0700 (PDT) From: David Brazdil To: Marc Zyngier , Will Deacon , Catalin Marinas , James Morse , Julien Thierry , Suzuki K Poulose Subject: [PATCH 1/2] KVM: arm64: Make nVHE ASLR conditional on RANDOMIZE_BASE Date: Tue, 21 Jul 2020 10:44:44 +0100 Message-Id: <20200721094445.82184-2-dbrazdil@google.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200721094445.82184-1-dbrazdil@google.com> References: <20200721094445.82184-1-dbrazdil@google.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200721_054500_969191_5DBEDA4E X-CRM114-Status: GOOD ( 13.81 ) 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: android-kvm@google.com, linux-kernel@vger.kernel.org, David Brazdil , kernel-team@android.com, kvmarm@lists.cs.columbia.edu, 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+linux-arm-kernel=archiver.kernel.org@lists.infradead.org If there are spare bits in non-VHE hyp VA, KVM unconditionally replaces them with a random tag chosen at init. Disable this if the kernel is built without RANDOMIZE_BASE to align with kernel behavior. Signed-off-by: David Brazdil --- arch/arm64/kvm/va_layout.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm64/kvm/va_layout.c b/arch/arm64/kvm/va_layout.c index a4f48c1ac28c..e0404bcab019 100644 --- a/arch/arm64/kvm/va_layout.c +++ b/arch/arm64/kvm/va_layout.c @@ -48,7 +48,7 @@ __init void kvm_compute_layout(void) va_mask = GENMASK_ULL(tag_lsb - 1, 0); tag_val = hyp_va_msb; - if (tag_lsb != (vabits_actual - 1)) { + if (IS_ENABLED(CONFIG_RANDOMIZE_BASE) && tag_lsb != (vabits_actual - 1)) { /* We have some free bits to insert a random tag. */ tag_val |= get_random_long() & GENMASK_ULL(vabits_actual - 2, tag_lsb); } -- 2.27.0 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel