KVM: emulator: Fix io permission checking for 64bit guest
Current implementation truncates upper 32bit of TR base address during IO
permission bitmap check. The patch fixes this.
Reported-and-tested-by: Francis Moreau <francis.moro@gmail.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index b9c2b8e..01f08a6 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -4162,8 +4162,8 @@
return get_segment_base(vcpu, seg);
}
-static bool emulator_get_cached_descriptor(struct desc_struct *desc, int seg,
- struct kvm_vcpu *vcpu)
+static bool emulator_get_cached_descriptor(struct desc_struct *desc, u32 *base3,
+ int seg, struct kvm_vcpu *vcpu)
{
struct kvm_segment var;
@@ -4176,6 +4176,10 @@
var.limit >>= 12;
set_desc_limit(desc, var.limit);
set_desc_base(desc, (unsigned long)var.base);
+#ifdef CONFIG_X86_64
+ if (base3)
+ *base3 = var.base >> 32;
+#endif
desc->type = var.type;
desc->s = var.s;
desc->dpl = var.dpl;
@@ -4188,8 +4192,8 @@
return true;
}
-static void emulator_set_cached_descriptor(struct desc_struct *desc, int seg,
- struct kvm_vcpu *vcpu)
+static void emulator_set_cached_descriptor(struct desc_struct *desc, u32 base3,
+ int seg, struct kvm_vcpu *vcpu)
{
struct kvm_segment var;
@@ -4197,6 +4201,9 @@
kvm_get_segment(vcpu, &var, seg);
var.base = get_desc_base(desc);
+#ifdef CONFIG_X86_64
+ var.base |= ((u64)base3) << 32;
+#endif
var.limit = get_desc_limit(desc);
if (desc->g)
var.limit = (var.limit << 12) | 0xfff;