KVM: SVM: Inject #UD for INVLPGA if EFER.SVME=0

commit d99df02 upstream.

INVLPGA should cause a #UD when EFER.SVME is not set. Add a check to
properly inject #UD when EFER.SVME=0.

Fixes: ff09238 ("KVM: SVM: Implement INVLPGA")
Cc: stable@vger.kernel.org
Signed-off-by: Kevin Cheng <chengkev@google.com>
Reviewed-by: Yosry Ahmed <yosry.ahmed@linux.dev>
Link: https://patch.msgid.link/20260228033328.2285047-3-chengkev@google.com
[sean: tag for stable@]
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: Kevin Cheng

arch/x86/kvm/svm/svm.c

@@ -2494,6 +2494,9 @@ static int invlpga_interception(struct kvm_vcpu *vcpu)
 	gva_t gva = kvm_rax_read(vcpu);
 	u32 asid = kvm_rcx_read(vcpu);
 
+	if (nested_svm_check_permissions(vcpu))
+		return 1;
+
 	/* FIXME: Handle an address size prefix. */
 	if (!is_long_mode(vcpu))
 		gva = (u32)gva;