From: Jim Mattson Date: Fri, 6 Dec 2019 15:46:36 -0800 Subject: kvm: nVMX: VMWRITE checks unsupported field before read-only field Git-commit: 693e02cc24090c379217138719d9d84e50036b24 Patch-mainline: v5.6-rc1 References: bsc#1164331 According to the SDM, VMWRITE checks to see if the secondary source operand corresponds to an unsupported VMCS field before it checks to see if the secondary source operand corresponds to a VM-exit information field and the processor does not support writing to VM-exit information fields. Fixes: 49f705c5324aa ("KVM: nVMX: Implement VMREAD and VMWRITE") Signed-off-by: Jim Mattson Cc: Paolo Bonzini Reviewed-by: Peter Shier Reviewed-by: Oliver Upton Reviewed-by: Jon Cargille Signed-off-by: Paolo Bonzini Acked-by: Joerg Roedel --- arch/x86/kvm/vmx/nested.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index a3ec92c316f6..e2fa5aefed29 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -4883,6 +4883,12 @@ static int handle_vmwrite(struct kvm_vcpu *vcpu) field = kvm_register_readl(vcpu, (((vmx_instruction_info) >> 28) & 0xf)); + + offset = vmcs_field_to_offset(field); + if (offset < 0) + return nested_vmx_failValid(vcpu, + VMXERR_UNSUPPORTED_VMCS_COMPONENT); + /* * If the vCPU supports "VMWRITE to any supported field in the * VMCS," then the "read-only" fields are actually read/write. @@ -4899,11 +4905,6 @@ static int handle_vmwrite(struct kvm_vcpu *vcpu) if (!is_guest_mode(vcpu) && !is_shadow_field_rw(field)) copy_vmcs02_to_vmcs12_rare(vcpu, vmcs12); - offset = vmcs_field_to_offset(field); - if (offset < 0) - return nested_vmx_failValid(vcpu, - VMXERR_UNSUPPORTED_VMCS_COMPONENT); - /* * Some Intel CPUs intentionally drop the reserved bits of the AR byte * fields on VMWRITE. Emulate this behavior to ensure consistent KVM