From 37f6a4e237303549c8676dfe1fd1991ceab512eb Mon Sep 17 00:00:00 2001 From: Marcelo Tosatti Date: Fri, 3 Jan 2014 17:09:32 -0200 Subject: KVM: x86: handle invalid root_hpa everywhere Rom Freiman notes other code paths vulnerable to bug fixed by 989c6b34f6a9480e397b. Signed-off-by: Marcelo Tosatti --- arch/x86/kvm/mmu.c | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'arch/x86/kvm/mmu.c') diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 31a570287fc..e50425d0f5f 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -2832,6 +2832,9 @@ static bool fast_page_fault(struct kvm_vcpu *vcpu, gva_t gva, int level, bool ret = false; u64 spte = 0ull; + if (!VALID_PAGE(vcpu->arch.mmu.root_hpa)) + return false; + if (!page_fault_can_be_fast(error_code)) return false; @@ -3227,6 +3230,9 @@ static u64 walk_shadow_page_get_mmio_spte(struct kvm_vcpu *vcpu, u64 addr) struct kvm_shadow_walk_iterator iterator; u64 spte = 0ull; + if (!VALID_PAGE(vcpu->arch.mmu.root_hpa)) + return spte; + walk_shadow_page_lockless_begin(vcpu); for_each_shadow_entry_lockless(vcpu, addr, iterator, spte) if (!is_shadow_present_pte(spte)) @@ -4513,6 +4519,9 @@ int kvm_mmu_get_spte_hierarchy(struct kvm_vcpu *vcpu, u64 addr, u64 sptes[4]) u64 spte; int nr_sptes = 0; + if (!VALID_PAGE(vcpu->arch.mmu.root_hpa)) + return nr_sptes; + walk_shadow_page_lockless_begin(vcpu); for_each_shadow_entry_lockless(vcpu, addr, iterator, spte) { sptes[iterator.level-1] = spte; -- cgit v1.2.3-18-g5258