commit 66570e966dd9 ("kvm: x86: only provide PV features if enabled in
guest's CPUID") only protects against disallowed guest writes to KVM
paravirtual msrs, leaving msr reads unchecked. Fix this by enforcing
KVM_CPUID_FEATURES for msr reads as well.
Fixes: 66570e966dd9 ("kvm: x86: only provide PV features if enabled in guest's CPUID")
Signed-off-by: Oliver Upton <oupton@xxxxxxxxxx>
Reviewed-by: Peter Shier <pshier@xxxxxxxxxx>
---
arch/x86/kvm/x86.c | 34 ++++++++++++++++++++++++++++++++++
1 file changed, 34 insertions(+)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 397f599b20e5..4016c07c8920 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3463,29 +3463,63 @@ int kvm_get_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
msr_info->data = vcpu->arch.efer;
break;
case MSR_KVM_WALL_CLOCK:
+ if (!guest_pv_has(vcpu, KVM_FEATURE_CLOCKSOURCE))
+ return 1;
+
+ msr_info->data = vcpu->kvm->arch.wall_clock;
+ break;
case MSR_KVM_WALL_CLOCK_NEW:
+ if (!guest_pv_has(vcpu, KVM_FEATURE_CLOCKSOURCE2))
+ return 1;
+
msr_info->data = vcpu->kvm->arch.wall_clock;
break;
case MSR_KVM_SYSTEM_TIME:
+ if (!guest_pv_has(vcpu, KVM_FEATURE_CLOCKSOURCE))
+ return 1;
+
+ msr_info->data = vcpu->arch.time;
+ break;
case MSR_KVM_SYSTEM_TIME_NEW:
+ if (!guest_pv_has(vcpu, KVM_FEATURE_CLOCKSOURCE2))
+ return 1;
+
msr_info->data = vcpu->arch.time;
break;
case MSR_KVM_ASYNC_PF_EN:
+ if (!guest_pv_has(vcpu, KVM_FEATURE_ASYNC_PF))
+ return 1;
+
msr_info->data = vcpu->arch.apf.msr_en_val;
break;
case MSR_KVM_ASYNC_PF_INT:
+ if (!guest_pv_has(vcpu, KVM_FEATURE_ASYNC_PF_INT))
+ return 1;
+
msr_info->data = vcpu->arch.apf.msr_int_val;
break;
case MSR_KVM_ASYNC_PF_ACK:
+ if (!guest_pv_has(vcpu, KVM_FEATURE_ASYNC_PF))
+ return 1;
+
msr_info->data = 0;
break;
case MSR_KVM_STEAL_TIME:
+ if (!guest_pv_has(vcpu, KVM_FEATURE_STEAL_TIME))
+ return 1;
+
msr_info->data = vcpu->arch.st.msr_val;
break;
case MSR_KVM_PV_EOI_EN:
+ if (!guest_pv_has(vcpu, KVM_FEATURE_PV_EOI))
+ return 1;
+
msr_info->data = vcpu->arch.pv_eoi.msr_val;
break;
case MSR_KVM_POLL_CONTROL:
+ if (!guest_pv_has(vcpu, KVM_FEATURE_POLL_CONTROL))
+ return 1;
+
msr_info->data = vcpu->arch.msr_kvm_poll_control;
break;
case MSR_IA32_P5_MC_ADDR:
--
2.29.0.rc2.309.g374f81d7ae-goog
