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 Received: from mm01.cs.columbia.edu (mm01.cs.columbia.edu [128.59.11.253]) by smtp.lore.kernel.org (Postfix) with ESMTP id AD498C433F5 for ; Wed, 27 Apr 2022 22:04:50 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 23EE240C0A; Wed, 27 Apr 2022 18:04:50 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Authentication-Results: mm01.cs.columbia.edu (amavisd-new); dkim=softfail (fail, message has been altered) header.i=@kernel.org Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id HKj8ByunuiWg; Wed, 27 Apr 2022 18:04:48 -0400 (EDT) Received: from mm01.cs.columbia.edu (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id DD1BB41049; Wed, 27 Apr 2022 18:04:48 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 024BB40BE7 for ; Wed, 27 Apr 2022 18:04:48 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Mgr1vPQlKQE2 for ; Wed, 27 Apr 2022 18:04:46 -0400 (EDT) Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id BD45B40BA9 for ; Wed, 27 Apr 2022 18:04:46 -0400 (EDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id CDBBA61E13; Wed, 27 Apr 2022 22:04:45 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 061F1C385A9; Wed, 27 Apr 2022 22:04:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1651097085; bh=pd+ppBS4AMOOPk2OjVc3EDZ0y0+9s9EffkC7oPOrVaA=; h=From:To:Cc:Subject:Date:From; b=bNd0y9GXq5k/qn0mRLOX7NDrArqeGsR6IzOkgOvtveIcb8irWHjo6I8JXX7U6wfyF lSrhzyx70dySogcKsWMtoVQq6oIOmNNbCICS6dDL+/oZOdMfw6v5Mk8YKjwLBZuwpY 6S6KEf99Zgjmx7/E0G7xXPQ0UcSzp7GrviE+cej2UfIYUzShMMV7wHSCxU5f9lcDzj iXESud4NQi2xXHC36GuAS80f/ZCigDGqxr4GR1wDf1L/9LKCPpni4Yni/OFOslwkrd dPpD919UPz2vAnTUBWgdNUsJ3qj6Z7xcNzzc2IxImlr1bqM8rvg1NlY4ft29WNSogB AzQErIphDSG5w== Received: from sofa.misterjones.org ([185.219.108.64] helo=hot-poop.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1njpm6-007U5C-Ix; Wed, 27 Apr 2022 23:04:42 +0100 From: Marc Zyngier To: kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu Subject: [PATCH v2] KVM: arm64: Inject exception on out-of-IPA-range translation fault Date: Wed, 27 Apr 2022 23:04:34 +0100 Message-Id: <20220427220434.3097449-1-maz@kernel.org> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, james.morse@arm.com, suzuki.poulose@arm.com, alexandru.elisei@arm.com, kernel-team@android.com, qperret@google.com, will@kernel.org, christoffer.dall@arm.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Cc: Will Deacon , kernel-team@android.com, Christoffer Dall 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 When taking a translation fault for an IPA that is outside of the range defined by the hypervisor (between the HW PARange and the IPA range), we stupidly treat it as an IO and forward the access to userspace. Of course, userspace can't do much with it, and things end badly. Arguably, the guest is braindead, but we should at least catch the case and inject an exception. Check the faulting IPA against: - the sanitised PARange: inject an address size fault - the IPA size: inject an abort Reported-by: Christoffer Dall Signed-off-by: Marc Zyngier --- arch/arm64/include/asm/kvm_emulate.h | 1 + arch/arm64/kvm/inject_fault.c | 28 ++++++++++++++++++++++++++++ arch/arm64/kvm/mmu.c | 19 +++++++++++++++++++ 3 files changed, 48 insertions(+) diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h index 7496deab025a..f71358271b71 100644 --- a/arch/arm64/include/asm/kvm_emulate.h +++ b/arch/arm64/include/asm/kvm_emulate.h @@ -40,6 +40,7 @@ void kvm_inject_undefined(struct kvm_vcpu *vcpu); void kvm_inject_vabt(struct kvm_vcpu *vcpu); void kvm_inject_dabt(struct kvm_vcpu *vcpu, unsigned long addr); void kvm_inject_pabt(struct kvm_vcpu *vcpu, unsigned long addr); +void kvm_inject_size_fault(struct kvm_vcpu *vcpu); void kvm_vcpu_wfi(struct kvm_vcpu *vcpu); diff --git a/arch/arm64/kvm/inject_fault.c b/arch/arm64/kvm/inject_fault.c index b47df73e98d7..ba20405d2dc2 100644 --- a/arch/arm64/kvm/inject_fault.c +++ b/arch/arm64/kvm/inject_fault.c @@ -145,6 +145,34 @@ void kvm_inject_pabt(struct kvm_vcpu *vcpu, unsigned long addr) inject_abt64(vcpu, true, addr); } +void kvm_inject_size_fault(struct kvm_vcpu *vcpu) +{ + unsigned long addr, esr; + + addr = kvm_vcpu_get_fault_ipa(vcpu); + addr |= kvm_vcpu_get_hfar(vcpu) & GENMASK(11, 0); + + if (kvm_vcpu_trap_is_iabt(vcpu)) + kvm_inject_pabt(vcpu, addr); + else + kvm_inject_dabt(vcpu, addr); + + /* + * If AArch64 or LPAE, set FSC to 0 to indicate an Address + * Size Fault at level 0, as if exceeding PARange. + * + * Non-LPAE guests will only get the external abort, as there + * is no way to to describe the ASF. + */ + if (vcpu_el1_is_32bit(vcpu) && + !(vcpu_read_sys_reg(vcpu, TCR_EL1) & TTBCR_EAE)) + return; + + esr = vcpu_read_sys_reg(vcpu, ESR_EL1); + esr &= ~GENMASK_ULL(5, 0); + vcpu_write_sys_reg(vcpu, esr, ESR_EL1); +} + /** * kvm_inject_undefined - inject an undefined instruction into the guest * @vcpu: The vCPU in which to inject the exception diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index 53ae2c0640bc..5400fc020164 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -1337,6 +1337,25 @@ int kvm_handle_guest_abort(struct kvm_vcpu *vcpu) fault_ipa = kvm_vcpu_get_fault_ipa(vcpu); is_iabt = kvm_vcpu_trap_is_iabt(vcpu); + if (fault_status == FSC_FAULT) { + /* Beyond sanitised PARange (which is the IPA limit) */ + if (fault_ipa >= BIT_ULL(get_kvm_ipa_limit())) { + kvm_inject_size_fault(vcpu); + return 1; + } + + /* Falls between the IPA range and the PARange? */ + if (fault_ipa >= BIT_ULL(vcpu->arch.hw_mmu->pgt->ia_bits)) { + fault_ipa |= kvm_vcpu_get_hfar(vcpu) & GENMASK(11, 0); + + if (is_iabt) + kvm_inject_pabt(vcpu, fault_ipa); + else + kvm_inject_dabt(vcpu, fault_ipa); + return 1; + } + } + /* Synchronous External Abort? */ if (kvm_vcpu_abt_issea(vcpu)) { /* -- 2.34.1 _______________________________________________ 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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 27A00C433EF for ; Wed, 27 Apr 2022 22:05:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-Id:Date:Subject:Cc :To:From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References: List-Owner; bh=goilhBDVnUGvuqJv0LRLCj7It5/HUxLBjXPdfh3QaRI=; b=ikNHgugfjf5fZx 0ketXipqsBT/YWMK7WzoibGiTEcKjE3wgFLZfo1/ie11m8E3eiy6jTvo1ZOwDU0cbLyyJDoLANPaW /I7P3hfnMUXvCZJndhA88F6HtqS0kIsSR/GwZg0YG2MqaDZTEOGBCd5op93+lJixw6J/9RbbiKIAT LiIZhzuLW4gnd2COBLd7XppMo38ecU9ctG7aI3hFaRBbEkdF2dmkkXsQhQSK+zp2F2SIQ1R0NBPnz bfcc/vrXAGafQOqcIvtgb5eIqc+JUfiF6BzodLZsHdekK8E0sMMxq608NHVgGX2t7zWTBfvn0bLqY POmWSTQuqdjZjyBoxsmQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1njpmD-003ipY-IF; Wed, 27 Apr 2022 22:04:49 +0000 Received: from dfw.source.kernel.org ([2604:1380:4641:c500::1]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1njpmA-003io4-97 for linux-arm-kernel@lists.infradead.org; Wed, 27 Apr 2022 22:04:47 +0000 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id CDBBA61E13; Wed, 27 Apr 2022 22:04:45 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 061F1C385A9; Wed, 27 Apr 2022 22:04:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1651097085; bh=pd+ppBS4AMOOPk2OjVc3EDZ0y0+9s9EffkC7oPOrVaA=; h=From:To:Cc:Subject:Date:From; b=bNd0y9GXq5k/qn0mRLOX7NDrArqeGsR6IzOkgOvtveIcb8irWHjo6I8JXX7U6wfyF lSrhzyx70dySogcKsWMtoVQq6oIOmNNbCICS6dDL+/oZOdMfw6v5Mk8YKjwLBZuwpY 6S6KEf99Zgjmx7/E0G7xXPQ0UcSzp7GrviE+cej2UfIYUzShMMV7wHSCxU5f9lcDzj iXESud4NQi2xXHC36GuAS80f/ZCigDGqxr4GR1wDf1L/9LKCPpni4Yni/OFOslwkrd dPpD919UPz2vAnTUBWgdNUsJ3qj6Z7xcNzzc2IxImlr1bqM8rvg1NlY4ft29WNSogB AzQErIphDSG5w== Received: from sofa.misterjones.org ([185.219.108.64] helo=hot-poop.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1njpm6-007U5C-Ix; Wed, 27 Apr 2022 23:04:42 +0100 From: Marc Zyngier To: kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu Cc: James Morse , Suzuki K Poulose , Alexandru Elisei , kernel-team@android.com, Quentin Perret , Will Deacon , Christoffer Dall Subject: [PATCH v2] KVM: arm64: Inject exception on out-of-IPA-range translation fault Date: Wed, 27 Apr 2022 23:04:34 +0100 Message-Id: <20220427220434.3097449-1-maz@kernel.org> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, james.morse@arm.com, suzuki.poulose@arm.com, alexandru.elisei@arm.com, kernel-team@android.com, qperret@google.com, will@kernel.org, christoffer.dall@arm.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220427_150446_442650_46A2DB44 X-CRM114-Status: GOOD ( 17.60 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , 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 When taking a translation fault for an IPA that is outside of the range defined by the hypervisor (between the HW PARange and the IPA range), we stupidly treat it as an IO and forward the access to userspace. Of course, userspace can't do much with it, and things end badly. Arguably, the guest is braindead, but we should at least catch the case and inject an exception. Check the faulting IPA against: - the sanitised PARange: inject an address size fault - the IPA size: inject an abort Reported-by: Christoffer Dall Signed-off-by: Marc Zyngier --- arch/arm64/include/asm/kvm_emulate.h | 1 + arch/arm64/kvm/inject_fault.c | 28 ++++++++++++++++++++++++++++ arch/arm64/kvm/mmu.c | 19 +++++++++++++++++++ 3 files changed, 48 insertions(+) diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h index 7496deab025a..f71358271b71 100644 --- a/arch/arm64/include/asm/kvm_emulate.h +++ b/arch/arm64/include/asm/kvm_emulate.h @@ -40,6 +40,7 @@ void kvm_inject_undefined(struct kvm_vcpu *vcpu); void kvm_inject_vabt(struct kvm_vcpu *vcpu); void kvm_inject_dabt(struct kvm_vcpu *vcpu, unsigned long addr); void kvm_inject_pabt(struct kvm_vcpu *vcpu, unsigned long addr); +void kvm_inject_size_fault(struct kvm_vcpu *vcpu); void kvm_vcpu_wfi(struct kvm_vcpu *vcpu); diff --git a/arch/arm64/kvm/inject_fault.c b/arch/arm64/kvm/inject_fault.c index b47df73e98d7..ba20405d2dc2 100644 --- a/arch/arm64/kvm/inject_fault.c +++ b/arch/arm64/kvm/inject_fault.c @@ -145,6 +145,34 @@ void kvm_inject_pabt(struct kvm_vcpu *vcpu, unsigned long addr) inject_abt64(vcpu, true, addr); } +void kvm_inject_size_fault(struct kvm_vcpu *vcpu) +{ + unsigned long addr, esr; + + addr = kvm_vcpu_get_fault_ipa(vcpu); + addr |= kvm_vcpu_get_hfar(vcpu) & GENMASK(11, 0); + + if (kvm_vcpu_trap_is_iabt(vcpu)) + kvm_inject_pabt(vcpu, addr); + else + kvm_inject_dabt(vcpu, addr); + + /* + * If AArch64 or LPAE, set FSC to 0 to indicate an Address + * Size Fault at level 0, as if exceeding PARange. + * + * Non-LPAE guests will only get the external abort, as there + * is no way to to describe the ASF. + */ + if (vcpu_el1_is_32bit(vcpu) && + !(vcpu_read_sys_reg(vcpu, TCR_EL1) & TTBCR_EAE)) + return; + + esr = vcpu_read_sys_reg(vcpu, ESR_EL1); + esr &= ~GENMASK_ULL(5, 0); + vcpu_write_sys_reg(vcpu, esr, ESR_EL1); +} + /** * kvm_inject_undefined - inject an undefined instruction into the guest * @vcpu: The vCPU in which to inject the exception diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index 53ae2c0640bc..5400fc020164 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -1337,6 +1337,25 @@ int kvm_handle_guest_abort(struct kvm_vcpu *vcpu) fault_ipa = kvm_vcpu_get_fault_ipa(vcpu); is_iabt = kvm_vcpu_trap_is_iabt(vcpu); + if (fault_status == FSC_FAULT) { + /* Beyond sanitised PARange (which is the IPA limit) */ + if (fault_ipa >= BIT_ULL(get_kvm_ipa_limit())) { + kvm_inject_size_fault(vcpu); + return 1; + } + + /* Falls between the IPA range and the PARange? */ + if (fault_ipa >= BIT_ULL(vcpu->arch.hw_mmu->pgt->ia_bits)) { + fault_ipa |= kvm_vcpu_get_hfar(vcpu) & GENMASK(11, 0); + + if (is_iabt) + kvm_inject_pabt(vcpu, fault_ipa); + else + kvm_inject_dabt(vcpu, fault_ipa); + return 1; + } + } + /* Synchronous External Abort? */ if (kvm_vcpu_abt_issea(vcpu)) { /* -- 2.34.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel 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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1C137C433EF for ; Wed, 27 Apr 2022 22:04:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238081AbiD0WIB (ORCPT ); Wed, 27 Apr 2022 18:08:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54462 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237989AbiD0WH7 (ORCPT ); Wed, 27 Apr 2022 18:07:59 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A764D82D37 for ; Wed, 27 Apr 2022 15:04:47 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 57E3EB82AE8 for ; Wed, 27 Apr 2022 22:04:46 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 061F1C385A9; Wed, 27 Apr 2022 22:04:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1651097085; bh=pd+ppBS4AMOOPk2OjVc3EDZ0y0+9s9EffkC7oPOrVaA=; h=From:To:Cc:Subject:Date:From; b=bNd0y9GXq5k/qn0mRLOX7NDrArqeGsR6IzOkgOvtveIcb8irWHjo6I8JXX7U6wfyF lSrhzyx70dySogcKsWMtoVQq6oIOmNNbCICS6dDL+/oZOdMfw6v5Mk8YKjwLBZuwpY 6S6KEf99Zgjmx7/E0G7xXPQ0UcSzp7GrviE+cej2UfIYUzShMMV7wHSCxU5f9lcDzj iXESud4NQi2xXHC36GuAS80f/ZCigDGqxr4GR1wDf1L/9LKCPpni4Yni/OFOslwkrd dPpD919UPz2vAnTUBWgdNUsJ3qj6Z7xcNzzc2IxImlr1bqM8rvg1NlY4ft29WNSogB AzQErIphDSG5w== Received: from sofa.misterjones.org ([185.219.108.64] helo=hot-poop.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1njpm6-007U5C-Ix; Wed, 27 Apr 2022 23:04:42 +0100 From: Marc Zyngier To: kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu Cc: James Morse , Suzuki K Poulose , Alexandru Elisei , kernel-team@android.com, Quentin Perret , Will Deacon , Christoffer Dall Subject: [PATCH v2] KVM: arm64: Inject exception on out-of-IPA-range translation fault Date: Wed, 27 Apr 2022 23:04:34 +0100 Message-Id: <20220427220434.3097449-1-maz@kernel.org> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, james.morse@arm.com, suzuki.poulose@arm.com, alexandru.elisei@arm.com, kernel-team@android.com, qperret@google.com, will@kernel.org, christoffer.dall@arm.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org When taking a translation fault for an IPA that is outside of the range defined by the hypervisor (between the HW PARange and the IPA range), we stupidly treat it as an IO and forward the access to userspace. Of course, userspace can't do much with it, and things end badly. Arguably, the guest is braindead, but we should at least catch the case and inject an exception. Check the faulting IPA against: - the sanitised PARange: inject an address size fault - the IPA size: inject an abort Reported-by: Christoffer Dall Signed-off-by: Marc Zyngier --- arch/arm64/include/asm/kvm_emulate.h | 1 + arch/arm64/kvm/inject_fault.c | 28 ++++++++++++++++++++++++++++ arch/arm64/kvm/mmu.c | 19 +++++++++++++++++++ 3 files changed, 48 insertions(+) diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h index 7496deab025a..f71358271b71 100644 --- a/arch/arm64/include/asm/kvm_emulate.h +++ b/arch/arm64/include/asm/kvm_emulate.h @@ -40,6 +40,7 @@ void kvm_inject_undefined(struct kvm_vcpu *vcpu); void kvm_inject_vabt(struct kvm_vcpu *vcpu); void kvm_inject_dabt(struct kvm_vcpu *vcpu, unsigned long addr); void kvm_inject_pabt(struct kvm_vcpu *vcpu, unsigned long addr); +void kvm_inject_size_fault(struct kvm_vcpu *vcpu); void kvm_vcpu_wfi(struct kvm_vcpu *vcpu); diff --git a/arch/arm64/kvm/inject_fault.c b/arch/arm64/kvm/inject_fault.c index b47df73e98d7..ba20405d2dc2 100644 --- a/arch/arm64/kvm/inject_fault.c +++ b/arch/arm64/kvm/inject_fault.c @@ -145,6 +145,34 @@ void kvm_inject_pabt(struct kvm_vcpu *vcpu, unsigned long addr) inject_abt64(vcpu, true, addr); } +void kvm_inject_size_fault(struct kvm_vcpu *vcpu) +{ + unsigned long addr, esr; + + addr = kvm_vcpu_get_fault_ipa(vcpu); + addr |= kvm_vcpu_get_hfar(vcpu) & GENMASK(11, 0); + + if (kvm_vcpu_trap_is_iabt(vcpu)) + kvm_inject_pabt(vcpu, addr); + else + kvm_inject_dabt(vcpu, addr); + + /* + * If AArch64 or LPAE, set FSC to 0 to indicate an Address + * Size Fault at level 0, as if exceeding PARange. + * + * Non-LPAE guests will only get the external abort, as there + * is no way to to describe the ASF. + */ + if (vcpu_el1_is_32bit(vcpu) && + !(vcpu_read_sys_reg(vcpu, TCR_EL1) & TTBCR_EAE)) + return; + + esr = vcpu_read_sys_reg(vcpu, ESR_EL1); + esr &= ~GENMASK_ULL(5, 0); + vcpu_write_sys_reg(vcpu, esr, ESR_EL1); +} + /** * kvm_inject_undefined - inject an undefined instruction into the guest * @vcpu: The vCPU in which to inject the exception diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index 53ae2c0640bc..5400fc020164 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -1337,6 +1337,25 @@ int kvm_handle_guest_abort(struct kvm_vcpu *vcpu) fault_ipa = kvm_vcpu_get_fault_ipa(vcpu); is_iabt = kvm_vcpu_trap_is_iabt(vcpu); + if (fault_status == FSC_FAULT) { + /* Beyond sanitised PARange (which is the IPA limit) */ + if (fault_ipa >= BIT_ULL(get_kvm_ipa_limit())) { + kvm_inject_size_fault(vcpu); + return 1; + } + + /* Falls between the IPA range and the PARange? */ + if (fault_ipa >= BIT_ULL(vcpu->arch.hw_mmu->pgt->ia_bits)) { + fault_ipa |= kvm_vcpu_get_hfar(vcpu) & GENMASK(11, 0); + + if (is_iabt) + kvm_inject_pabt(vcpu, fault_ipa); + else + kvm_inject_dabt(vcpu, fault_ipa); + return 1; + } + } + /* Synchronous External Abort? */ if (kvm_vcpu_abt_issea(vcpu)) { /* -- 2.34.1