On Sat, 2023-01-07 at 01:10 +0000, Sean Christopherson wrote: > 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 <marcorr@xxxxxxxxxx> > Cc: Ben Gardon <bgardon@xxxxxxxxxx> > Cc: Venkatesh Srinivas <venkateshs@xxxxxxxxxxxx> > Cc: stable@xxxxxxxxxxxxxxx > Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx> > --- > arch/x86/kvm/lapic.c | 10 +++++++--- > 1 file changed, 7 insertions(+), 3 deletions(-) > > diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c > index 80f92cbc4029..f77da92c6ea6 100644 > --- a/arch/x86/kvm/lapic.c > +++ b/arch/x86/kvm/lapic.c > @@ -2315,10 +2315,14 @@ 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; Reviewed-by: Maxim Levitsky <mlevitsk@xxxxxxxxxx> Best regards, Maxim Levitsky
