[Qemu-devel] 答复: [PATCH v2] net: ne2000: check ring buffer control registers

[yanghongke]

On 02/24/2016 02:11 PM, P J P wrote:
> From: Prasad J Pandit <address@hidden>
>
> Ne2000 NIC uses ring buffer of NE2000_MEM_SIZE(49152) bytes to process 
> network packets. Registers PSTART & PSTOP define ring buffer size & 
> location. Setting these registers to invalid values could lead to 
> infinite loop or OOB r/w access issues. Add check to avoid it.
>
> Reported-by: Yang Hongke <address@hidden>
> Signed-off-by: Prasad J Pandit <address@hidden>
> Tested-by: Yang Hongke <address@hidden>
> ---
>  hw/net/ne2000.c | 4 ++++
>  1 file changed, 4 insertions(+)
>
> Update per review:
>   -> 
> https://lists.gnu.org/archive/html/qemu-devel/2016-02/msg05522.html
>
> diff --git a/hw/net/ne2000.c b/hw/net/ne2000.c index b032212..ced4666 
> 100644
> --- a/hw/net/ne2000.c
> +++ b/hw/net/ne2000.c
> @@ -154,6 +154,10 @@ static int ne2000_buffer_full(NE2000State *s)  {
>      int avail, index, boundary;
>  
> +    if (s->stop <= s->start) {
> +        return 1;
> +    }
> +
>      index = s->curpag << 8;
>      boundary = s->boundary << 8;
>      if (index < boundary)

After my test, the issue is fixed with this patch.