From: Nitesh Narayan Lal Date: Fri, 13 Mar 2020 13:16:24 +0000 (-0400) Subject: KVM: x86: Initializing all kvm_lapic_irq fields in ioapic_write_indirect X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=0c22056f8c43265da21a3dfe7b7e1379e5ff7c72;p=linux.git KVM: x86: Initializing all kvm_lapic_irq fields in ioapic_write_indirect Previously all fields of structure kvm_lapic_irq were not initialized before it was passed to kvm_bitmap_or_dest_vcpus(). Which will cause an issue when any of those fields are used for processing a request. For example not initializing the msi_redir_hint field before passing to the kvm_bitmap_or_dest_vcpus(), may lead to a misbehavior of kvm_apic_map_get_dest_lapic(). This will specifically happen when the kvm_lowest_prio_delivery() returns TRUE due to a non-zero garbage value of msi_redir_hint, which should not happen as the request belongs to APIC fixed delivery mode and we do not want to deliver the interrupt only to the lowest priority candidate. This patch initializes all the fields of kvm_lapic_irq based on the values of ioapic redirect_entry object before passing it on to kvm_bitmap_or_dest_vcpus(). Fixes: 7ee30bc132c6 ("KVM: x86: deliver KVM IOAPIC scan request to target vCPUs") Signed-off-by: Nitesh Narayan Lal Reviewed-by: Vitaly Kuznetsov [Set level to false since the value doesn't really matter. Suggested by Vitaly Kuznetsov. - Paolo] Signed-off-by: Paolo Bonzini --- diff --git a/arch/x86/kvm/ioapic.c b/arch/x86/kvm/ioapic.c index 7668fed1ce652..750ff0b294047 100644 --- a/arch/x86/kvm/ioapic.c +++ b/arch/x86/kvm/ioapic.c @@ -378,12 +378,15 @@ static void ioapic_write_indirect(struct kvm_ioapic *ioapic, u32 val) if (e->fields.delivery_mode == APIC_DM_FIXED) { struct kvm_lapic_irq irq; - irq.shorthand = APIC_DEST_NOSHORT; irq.vector = e->fields.vector; irq.delivery_mode = e->fields.delivery_mode << 8; - irq.dest_id = e->fields.dest_id; irq.dest_mode = kvm_lapic_irq_dest_mode(!!e->fields.dest_mode); + irq.level = false; + irq.trig_mode = e->fields.trig_mode; + irq.shorthand = APIC_DEST_NOSHORT; + irq.dest_id = e->fields.dest_id; + irq.msi_redir_hint = false; bitmap_zero(&vcpu_bitmap, 16); kvm_bitmap_or_dest_vcpus(ioapic->kvm, &irq, &vcpu_bitmap);