KVM: x86: Inject #GP if WRMSR sets reserved bits in APIC Self-IPI

Inject a #GP if the guest attempts to set reserved bits in the x2APIC-only
Self-IPI register.  Bits 7:0 hold the vector, all other bits are reserved.

Reported-by: Marc Orr <[email protected]>
Cc: Ben Gardon <[email protected]>
Cc: Venkatesh Srinivas <[email protected]>
Cc: [email protected]
Reviewed-by: Maxim Levitsky <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Sean Christopherson <[email protected]>
This commit is contained in:
Sean Christopherson committed 2023-01-24 10:04:34 -08:00
1 parent 85e64d09f7
commit ba5838abb0
1 file changed
+7 -3
+7 -3
View File
@@ -2324,10 +2324,14 @@ static int kvm_lapic_reg_write(struct kvm_lapic *apic, u32 reg, u32 val)
break;
case APIC_SELF_IPI:
if (apic_x2apic_mode(apic))
kvm_apic_send_ipi(apic, APIC_DEST_SELF | (val & APIC_VECTOR_MASK), 0);
else
/*
* Self-IPI exists only when x2APIC is enabled. Bits 7:0 hold
* the vector, everything else is reserved.
*/
if (!apic_x2apic_mode(apic) || (val & ~APIC_VECTOR_MASK))
ret = 1;
else
kvm_apic_send_ipi(apic, APIC_DEST_SELF | val, 0);
break;
default:
ret = 1;