[PATCH v2 2/8] KVM: x86: nSVM: Cache g_pat in vmcb_save_area_cached

[Jim Mattson]

To avoid TOCTTOU issues, all fields in the vmcb12 save area that are
subject to validation must be copied to svm->nested.save prior to
validation, since vmcb12 is writable by the guest. Add g_pat to this set in
preparation for validting it.

Fixes: 3d6368ef580a ("KVM: SVM: Add VMRUN handler")
Signed-off-by: Jim Mattson <jmatt...@google.com>
---
 arch/x86/kvm/svm/nested.c | 2 ++
 arch/x86/kvm/svm/svm.h    | 1 +
 2 files changed, 3 insertions(+)

diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index f295a41ec659..07a57a43fc3b 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -506,6 +506,8 @@ static void __nested_copy_vmcb_save_to_cache(struct 
vmcb_save_area_cached *to,
 
        to->dr6 = from->dr6;
        to->dr7 = from->dr7;
+
+       to->g_pat = from->g_pat;
 }
 
 void nested_copy_vmcb_save_to_cache(struct vcpu_svm *svm,
diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h
index 7d28a739865f..39138378531e 100644
--- a/arch/x86/kvm/svm/svm.h
+++ b/arch/x86/kvm/svm/svm.h
@@ -145,6 +145,7 @@ struct vmcb_save_area_cached {
        u64 cr0;
        u64 dr7;
        u64 dr6;
+       u64 g_pat;
 };
 
 struct vmcb_ctrl_area_cached {
-- 
2.52.0.457.g6b5491de43-goog