1 files changed, 11 insertions, 0 deletions

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 8d860e0301a0..279318677911 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -4410,6 +4410,15 @@ static int is_vm86_segment(struct kvm_vcpu *vcpu, int seg)
                 (kvm_get_rflags(vcpu) & X86_EFLAGS_VM);
 }
 
+static void kvm_check_segment_descriptor(struct kvm_vcpu *vcpu, int seg,
+                                         u16 selector)
+{
+        /* NULL selector is not valid for CS and SS */
+        if (seg == VCPU_SREG_CS || seg == VCPU_SREG_SS)
+                if (!selector)
+                        kvm_queue_exception_e(vcpu, TS_VECTOR, selector >> 3);
+}
+
 int kvm_load_segment_descriptor(struct kvm_vcpu *vcpu, u16 selector,
                                 int type_bits, int seg)
 {
@@ -4419,6 +4428,8 @@ int kvm_load_segment_descriptor(struct kvm_vcpu *vcpu, u16 selector,
                 return kvm_load_realmode_segment(vcpu, selector, seg);
         if (load_segment_descriptor_to_kvm_desct(vcpu, selector, &kvm_seg))
                 return 1;
+
+        kvm_check_segment_descriptor(vcpu, seg, selector);
         kvm_seg.type |= type_bits;
 
         if (seg != VCPU_SREG_SS && seg != VCPU_SREG_CS &&