Re: [Qemu-devel] [PATCH] net: vmxnet3: check for device_active before write

[Dmitry Fleytman]

Acked-by: Dmitry Fleytman <address@hidden>

> On 8 Aug 2016, at 15:38 PM, P J P <address@hidden> wrote:
> 
> From: Li Qiang <address@hidden>
> 
> Vmxnet3 device emulator does not check if the device is active,
> before using it for write. It leads to a use after free issue,
> if the vmxnet3_io_bar0_write routine is called after the device is
> deactivated. Add check to avoid it.
> 
> Reported-by: Li Qiang <address@hidden>
> Signed-off-by: Prasad J Pandit <address@hidden>
> ---
> hw/net/vmxnet3.c | 4 ++++
> 1 file changed, 4 insertions(+)
> 
> diff --git a/hw/net/vmxnet3.c b/hw/net/vmxnet3.c
> index bbf44ad..90f6943 100644
> --- a/hw/net/vmxnet3.c
> +++ b/hw/net/vmxnet3.c
> @@ -1167,6 +1167,10 @@ vmxnet3_io_bar0_write(void *opaque, hwaddr addr,
> {
>     VMXNET3State *s = opaque;
> 
> +    if (!s->device_active) {
> +        return;
> +    }
> +
>     if (VMW_IS_MULTIREG_ADDR(addr, VMXNET3_REG_TXPROD,
>                         VMXNET3_DEVICE_MAX_TX_QUEUES, VMXNET3_REG_ALIGN)) {
>         int tx_queue_idx =
> -- 
> 2.5.5
>