diff mbox series

KVM: x86: Zero the IOAPIC scan request dest vCPUs bitmap

Message ID 20191120121224.9850-1-nitesh@redhat.com (mailing list archive)
State New, archived
Headers show
Series KVM: x86: Zero the IOAPIC scan request dest vCPUs bitmap | expand

Commit Message

Nitesh Narayan Lal Nov. 20, 2019, 12:12 p.m. UTC
Not zeroing the bitmap used for identifying the destination vCPUs for an
IOAPIC scan request in fixed delivery mode could lead to waking up unwanted
vCPUs. This patch zeroes the vCPU bitmap before passing it to
kvm_bitmap_or_dest_vcpus(), which is responsible for setting the bitmap
with the bits corresponding to the destination vCPUs.

Fixes: 7ee30bc132c6("KVM: x86: deliver KVM IOAPIC scan request to target vCPUs")
Signed-off-by: Nitesh Narayan Lal <nitesh@redhat.com>
---
 arch/x86/kvm/ioapic.c | 1 +
 1 file changed, 1 insertion(+)

Comments

Paolo Bonzini Nov. 20, 2019, 12:33 p.m. UTC | #1
On 20/11/19 13:12, Nitesh Narayan Lal wrote:
> Not zeroing the bitmap used for identifying the destination vCPUs for an
> IOAPIC scan request in fixed delivery mode could lead to waking up unwanted
> vCPUs. This patch zeroes the vCPU bitmap before passing it to
> kvm_bitmap_or_dest_vcpus(), which is responsible for setting the bitmap
> with the bits corresponding to the destination vCPUs.
> 
> Fixes: 7ee30bc132c6("KVM: x86: deliver KVM IOAPIC scan request to target vCPUs")
> Signed-off-by: Nitesh Narayan Lal <nitesh@redhat.com>
> ---
>  arch/x86/kvm/ioapic.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/arch/x86/kvm/ioapic.c b/arch/x86/kvm/ioapic.c
> index ce30ef23c86b..9fd2dd89a1c5 100644
> --- a/arch/x86/kvm/ioapic.c
> +++ b/arch/x86/kvm/ioapic.c
> @@ -332,6 +332,7 @@ static void ioapic_write_indirect(struct kvm_ioapic *ioapic, u32 val)
>  			irq.delivery_mode = e->fields.delivery_mode << 8;
>  			irq.dest_id = e->fields.dest_id;
>  			irq.dest_mode = e->fields.dest_mode;
> +			bitmap_zero(&vcpu_bitmap, 16);
>  			kvm_bitmap_or_dest_vcpus(ioapic->kvm, &irq,
>  						 &vcpu_bitmap);
>  			if (old_dest_mode != e->fields.dest_mode ||
> 

Queued, thanks.

Paolo
diff mbox series

Patch

diff --git a/arch/x86/kvm/ioapic.c b/arch/x86/kvm/ioapic.c
index ce30ef23c86b..9fd2dd89a1c5 100644
--- a/arch/x86/kvm/ioapic.c
+++ b/arch/x86/kvm/ioapic.c
@@ -332,6 +332,7 @@  static void ioapic_write_indirect(struct kvm_ioapic *ioapic, u32 val)
 			irq.delivery_mode = e->fields.delivery_mode << 8;
 			irq.dest_id = e->fields.dest_id;
 			irq.dest_mode = e->fields.dest_mode;
+			bitmap_zero(&vcpu_bitmap, 16);
 			kvm_bitmap_or_dest_vcpus(ioapic->kvm, &irq,
 						 &vcpu_bitmap);
 			if (old_dest_mode != e->fields.dest_mode ||