On 191107 1221, Jason Wang wrote:
>
> On 2019/7/22 下午9:24, 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 <alx...@bu.edu>
> > ---
> > v2:
> > * Improve the comment to explain the rationale for adding the assert.
> > net/net.c | 9 +++++++++
> > 1 file changed, 9 insertions(+)
> >
> > diff --git a/net/net.c b/net/net.c
> > index 7d4098254f..4ad21df36f 100644
> > --- a/net/net.c
> > +++ b/net/net.c
> > @@ -741,6 +741,15 @@ ssize_t qemu_sendv_packet_async(NetClientState *sender,
> > size_t size = iov_size(iov, iovcnt);
> > int ret;
> > + /*
> > + * Since this function returns the size of the sent packets, and a
> > return
> > + * value of zero indicates that the packet will be sent asynchronously,
> > + * there is currently no way to report that a 0-sized packet has been
> > sent
> > + * successfully. Forbid it for now, and if someone needs this
> > functionality
> > + * later, the API will require a change.
> > + */
> > + assert(size);
>
>
> This probably will make the assertion triggerable from guest. Is this better
> to warn and return NET_BUFSIZE + 1 here?
Will do. I'll send a v3 out with this change.
Thank you
> Thanks
>
>
> > +
> > if (size > NET_BUFSIZE) {
> > return size;
> > }
>
