Commit 8060b2bd authored by Chao Gao's avatar Chao Gao Committed by Sean Christopherson
Browse files

KVM: nVMX: Add consistency checks for CR0.WP and CR4.CET 



Add consistency checks for CR4.CET and CR0.WP in guest-state or host-state
area in the VMCS12. This ensures that configurations with CR4.CET set and
CR0.WP not set result in VM-entry failure, aligning with architectural
behavior.

Tested-by: default avatarMathias Krause <minipli@grsecurity.net>
Tested-by: default avatarJohn Allen <john.allen@amd.com>
Tested-by: default avatarRick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: default avatarChao Gao <chao.gao@intel.com>
Reviewed-by: default avatarBinbin Wu <binbin.wu@linux.intel.com>
Link: https://lore.kernel.org/r/20250919223258.1604852-33-seanjc@google.com


Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
parent 62588499

arch/x86/kvm/vmx/nested.c

+6 −0
Original line number Diff line number Diff line
@@ -3110,6 +3110,9 @@ static int nested_vmx_check_host_state(struct kvm_vcpu *vcpu, 
	    CC(!kvm_vcpu_is_legal_cr3(vcpu, vmcs12->host_cr3)))

		return -EINVAL;



	if (CC(vmcs12->host_cr4 & X86_CR4_CET && !(vmcs12->host_cr0 & X86_CR0_WP)))

		return -EINVAL;



	if (CC(is_noncanonical_msr_address(vmcs12->host_ia32_sysenter_esp, vcpu)) ||

	    CC(is_noncanonical_msr_address(vmcs12->host_ia32_sysenter_eip, vcpu)))

		return -EINVAL;
@@ -3224,6 +3227,9 @@ static int nested_vmx_check_guest_state(struct kvm_vcpu *vcpu, 
	    CC(!nested_guest_cr4_valid(vcpu, vmcs12->guest_cr4)))

		return -EINVAL;



	if (CC(vmcs12->guest_cr4 & X86_CR4_CET && !(vmcs12->guest_cr0 & X86_CR0_WP)))

		return -EINVAL;



	if ((vmcs12->vm_entry_controls & VM_ENTRY_LOAD_DEBUG_CONTROLS) &&

	    (CC(!kvm_dr7_valid(vmcs12->guest_dr7)) ||

	     CC(!vmx_is_valid_debugctl(vcpu, vmcs12->guest_ia32_debugctl, false))))