From b3f1dfb6e818a2352c38e3e37bb983eae98621b5 Mon Sep 17 00:00:00 2001 From: Jim Mattson Date: Mon, 17 Jul 2017 12:00:34 -0700 Subject: [PATCH] KVM: nVMX: Disallow VM-entry in MOV-SS shadow MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Immediately following MOV-to-SS/POP-to-SS, VM-entry is disallowed. This check comes after the check for a valid VMCS. When this check fails, the instruction pointer should fall through to the next instruction, the ALU flags should be set to indicate VMfailValid, and the VM-instruction error should be set to 26 ("VM entry with events blocked by MOV SS"). Signed-off-by: Jim Mattson Signed-off-by: Radim Krčmář --- arch/x86/kvm/vmx.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index a0c472bcb2a2..791c018a0034 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -10492,6 +10492,7 @@ static int nested_vmx_run(struct kvm_vcpu *vcpu, bool launch) { struct vmcs12 *vmcs12; struct vcpu_vmx *vmx = to_vmx(vcpu); + u32 interrupt_shadow = vmx_get_interrupt_shadow(vcpu); u32 exit_qual; int ret; @@ -10516,6 +10517,12 @@ static int nested_vmx_run(struct kvm_vcpu *vcpu, bool launch) * for misconfigurations which will anyway be caught by the processor * when using the merged vmcs02. */ + if (interrupt_shadow & KVM_X86_SHADOW_INT_MOV_SS) { + nested_vmx_failValid(vcpu, + VMXERR_ENTRY_EVENTS_BLOCKED_BY_MOV_SS); + goto out; + } + if (vmcs12->launch_state == launch) { nested_vmx_failValid(vcpu, launch ? VMXERR_VMLAUNCH_NONCLEAR_VMCS -- 2.20.1