Re: [Qemu-devel] [PATCH 1/2] net: assert that tx packets have nonzero size

[Jason Wang]

On 2019/7/20 上午2:52, Oleinik, Alexander wrote:
> Virtual devices should not try to send zero-sized packets. The caller
> should check the size prior to calling qemu_sendv_packet_async.
>
> Signed-off-by: Alexander Oleinik <address@hidden>
> ---
>   net/net.c | 3 +++
>   1 file changed, 3 insertions(+)
>
> diff --git a/net/net.c b/net/net.c
> index 7d4098254f..fad20bc611 100644
> --- a/net/net.c
> +++ b/net/net.c
> @@ -741,6 +741,9 @@ ssize_t qemu_sendv_packet_async(NetClientState *sender,
>       size_t size = iov_size(iov, iovcnt);
>       int ret;
>   
> +    /* 0-sized packets are unsupported. Check size in the caller */
> +    assert(size);


Can this be triggered through a buggy device by guest? If yes, we need 
avoid using assert() here.

Thanks


> +
>       if (size > NET_BUFSIZE) {
>           return size;
>       }