From b7aa71e12002da7369122dd17ff305bfeedf7f1c Mon Sep 17 00:00:00 2001 From: Marcelo Tosatti <mtosatti@redhat.com> Date: Tue, 26 May 2009 11:53:35 -0300 Subject: [PATCH] KVM: x86: check for cr3 validity in mmu_alloc_roots commit 89da4ff17f568bb3a1f69dce7e4c57a7f3bc0c63 Author: Marcelo Tosatti <mtosatti@redhat.com> Date: Tue May 12 18:55:45 2009 -0300 KVM: x86: check for cr3 validity in mmu_alloc_roots Verify the cr3 address stored in vcpu->arch.cr3 points to an existant memslot. If not, inject a triple fault. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com> Message-ID: <20090526145334.GD17390@amt.cnet> Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> RH-Upstream-status: applied(kvm/master) Acked-by: Marcelo Tosatti <mtosatti@redhat.com> Acked-by: Juan Quintela <quintela@redhat.com> Acked-by: Avi Kivity <avi@redhat.com> Bugzilla: 504237 --- arch/x86/kvm/mmu.c | 27 +++++++++++++++++++++++---- arch/x86/kvm/x86.c | 1 + 2 files changed, 24 insertions(+), 4 deletions(-) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 256bff9..247dca3 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -2027,7 +2027,19 @@ static void mmu_free_roots(struct kvm_vcpu *vcpu) vcpu->arch.mmu.root_hpa = INVALID_PAGE; } -static void mmu_alloc_roots(struct kvm_vcpu *vcpu) +static int mmu_check_root(struct kvm_vcpu *vcpu, gfn_t root_gfn) +{ + int ret = 0; + + if (!kvm_is_visible_gfn(vcpu->kvm, root_gfn)) { + set_bit(KVM_REQ_TRIPLE_FAULT, &vcpu->requests); + ret = 1; + } + + return ret; +} + +static int mmu_alloc_roots(struct kvm_vcpu *vcpu) { int i; gfn_t root_gfn; @@ -2042,13 +2054,15 @@ static void mmu_alloc_roots(struct kvm_vcpu *vcpu) ASSERT(!VALID_PAGE(root)); if (tdp_enabled) metaphysical = 1; + if (mmu_check_root(vcpu, root_gfn)) + return 1; sp = kvm_mmu_get_page(vcpu, root_gfn, 0, PT64_ROOT_LEVEL, metaphysical, ACC_ALL, NULL); root = __pa(sp->spt); ++sp->root_count; vcpu->arch.mmu.root_hpa = root; - return; + return 0; } metaphysical = !is_paging(vcpu); if (tdp_enabled) @@ -2065,6 +2079,8 @@ static void mmu_alloc_roots(struct kvm_vcpu *vcpu) root_gfn = vcpu->arch.pdptrs[i] >> PAGE_SHIFT; } else if (vcpu->arch.mmu.root_level == 0) root_gfn = 0; + if (mmu_check_root(vcpu, root_gfn)) + return 1; sp = kvm_mmu_get_page(vcpu, root_gfn, i << 30, PT32_ROOT_LEVEL, metaphysical, ACC_ALL, NULL); @@ -2073,6 +2089,7 @@ static void mmu_alloc_roots(struct kvm_vcpu *vcpu) vcpu->arch.mmu.pae_root[i] = root | PT_PRESENT_MASK; } vcpu->arch.mmu.root_hpa = __pa(vcpu->arch.mmu.pae_root); + return 0; } static void mmu_sync_roots(struct kvm_vcpu *vcpu) @@ -2091,7 +2108,7 @@ static void mmu_sync_roots(struct kvm_vcpu *vcpu) for (i = 0; i < 4; ++i) { hpa_t root = vcpu->arch.mmu.pae_root[i]; - if (root) { + if (root && VALID_PAGE(root)) { root &= PT64_BASE_ADDR_MASK; sp = page_header(root); mmu_sync_children(vcpu, sp); @@ -2369,9 +2386,11 @@ int kvm_mmu_load(struct kvm_vcpu *vcpu) goto out; spin_lock(&vcpu->kvm->mmu_lock); kvm_mmu_free_some_pages(vcpu); - mmu_alloc_roots(vcpu); + r = mmu_alloc_roots(vcpu); mmu_sync_roots(vcpu); spin_unlock(&vcpu->kvm->mmu_lock); + if (r) + goto out; kvm_x86_ops->set_cr3(vcpu, vcpu->arch.mmu.root_hpa); kvm_mmu_flush_tlb(vcpu); out: diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 39f7843..f61e915 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -4356,6 +4356,7 @@ int kvm_arch_set_memory_region(struct kvm *kvm, void kvm_arch_flush_shadow(struct kvm *kvm) { kvm_mmu_zap_all(kvm); + kvm_reload_remote_mmus(kvm); } int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu) -- 1.6.3.rc4.29.g8146