KVM: nVMX: add missing consistency checks for CR0 and CR4

stable inclusion
from stable-v5.10.176
commit c54974ccaff73525462e278602dfe4069877cfaa
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/I6U7AN
CVE: CVE-2023-30456

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=c54974ccaff73525462e278602dfe4069877cfaa

--------------------------------

commit 112e6601 upstream.

The effective values of the guest CR0 and CR4 registers may differ from
those included in the VMCS12.  In particular, disabling EPT forces
CR4.PAE=1 and disabling unrestricted guest mode forces CR0.PG=CR0.PE=1.

Therefore, checks on these bits cannot be delegated to the processor
and must be performed by KVM.
Reported-by: NReima ISHII <ishiir@g.ecc.u-tokyo.ac.jp>
Cc: stable@vger.kernel.org
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

conflicts:
	arch/x86/kvm/vmx.c
Signed-off-by: NLin Yujun <linyujun809@huawei.com>
Reviewed-by: NXiu Jianfeng <xiujianfeng@huawei.com>
Reviewed-by: NZhang Jianhua <chris.zjh@huawei.com>
Signed-off-by: NYongqiang Liu <liuyongqiang13@huawei.com>

arch/x86/kvm/vmx.c

@@ -12763,7 +12763,7 @@ static int nested_vmx_check_vmcs_link_ptr(struct kvm_vcpu *vcpu,
 static int check_vmentry_postreqs(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12,
 				  u32 *exit_qual)
 {
-	bool ia32e;
+	bool ia32e = !!(vmcs12->vm_entry_controls & VM_ENTRY_IA32E_MODE);
 
 	*exit_qual = ENTRY_FAIL_DEFAULT;
 
@@ -12776,6 +12776,13 @@ static int check_vmentry_postreqs(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12,
 		return 1;
 	}
 
+	if ((vmcs12->guest_cr0 & (X86_CR0_PG | X86_CR0_PE)) == X86_CR0_PG)
+		return 1;
+
+	if ((ia32e && !(vmcs12->guest_cr4 & X86_CR4_PAE)) ||
+	    (ia32e && !(vmcs12->guest_cr0 & X86_CR0_PG)))
+		return 1;
+
 	/*
 	 * If the load IA32_EFER VM-entry control is 1, the following checks
 	 * are performed on the field for the IA32_EFER MSR:
@@ -12787,7 +12794,6 @@ static int check_vmentry_postreqs(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12,
 	 */
 	if (to_vmx(vcpu)->nested.nested_run_pending &&
 	    (vmcs12->vm_entry_controls & VM_ENTRY_LOAD_IA32_EFER)) {
-		ia32e = (vmcs12->vm_entry_controls & VM_ENTRY_IA32E_MODE) != 0;
 		if (!kvm_valid_efer(vcpu, vmcs12->guest_ia32_efer) ||
 		    ia32e != !!(vmcs12->guest_ia32_efer & EFER_LMA) ||
 		    ((vmcs12->guest_cr0 & X86_CR0_PG) &&