[PATCH] KVM: nSVM: Gate CET state copy in svm_copy_vmrun_state() on guest SHSTK

[Jim Mattson <jmattson@google.com>]

Like nested_vmcb02_prepare_save() and nested_svm_vmexit_update_vmcb12(),
svm_copy_vmrun_state() should gate copying s_cet, isst_addr, and ssp on
guest_cpu_cap_has(vcpu, X86_FEATURE_SHSTK) (i.e. the feature is advertised
to the guest). Instead, copying is gated on
kvm_cpu_cap_has(X86_FEATURE_SHSTK) (i.e. the host supports shadow stacks).

Check guest_cpu_cap_has(vcpu, X86_FEATURE_SHSTK) instead of
kvm_cpu_cap_has(X86_FEATURE_SHSTK) in svm_copy_vmrun_state().

Fixes: c5ba49458513 ("KVM: nSVM: Save/load CET Shadow Stack state to/from vmcb12/vmcb02")
Signed-off-by: Jim Mattson <jmattson@google.com>
---
 arch/x86/kvm/svm/nested.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index 1299fdadeb73..b73bc9c3ebdb 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -1248,7 +1248,7 @@ void svm_copy_vmrun_state(struct kvm_vcpu *vcpu, struct vmcb_save_area *to_save,
 	to_save->rip = from_save->rip;
 	to_save->cpl = 0;
 
-	if (kvm_cpu_cap_has(X86_FEATURE_SHSTK)) {
+	if (guest_cpu_cap_has(vcpu, X86_FEATURE_SHSTK)) {
 		to_save->s_cet  = from_save->s_cet;
 		to_save->isst_addr = from_save->isst_addr;
 		to_save->ssp = from_save->ssp;
-- 
2.56.1.703.gf848ed807c-goog