Re: [Qemu-devel] [PATCH V4 for 3.1 0/4] Fix possible OOB during queuing packets

From: Jason Wang <jasowang@redhat.com>
To: Peter Maydell <peter.maydell@linaro.org>
Cc: QEMU Developers <qemu-devel@nongnu.org>,
	"Michael S. Tsirkin" <mst@redhat.com>, P J P <ppandit@redhat.com>,
	Li Qiang <liq3ea@163.com>, Li Qiang <liq3ea@gmail.com>,
	Paolo Bonzini <pbonzini@redhat.com>,
	Thomas Huth <thuth@redhat.com>, Eric Blake <eblake@redhat.com>
Subject: Re: [Qemu-devel] [PATCH V4 for 3.1 0/4] Fix possible OOB during queuing packets
Date: Tue, 4 Dec 2018 10:28:32 +0800	[thread overview]
Message-ID: <eaf87c46-3306-876c-8fb5-6b4f391c3f00@redhat.com> (raw)
In-Reply-To: <CAFEAcA-n+vJ505AF1xzq6y4HUab8ivX-4sQ29jBXsogfZh0=FQ@mail.gmail.com>

On 2018/12/4 上午12:18, Peter Maydell wrote:
> On Mon, 3 Dec 2018 at 10:06, Jason Wang <jasowang@redhat.com> wrote:
>> Hi:
>>
>> This series tries to fix a possible OOB during queueing packets
>> through qemu_net_queue_append_iov(). This could happen when it tries
>> to queue a packet whose size is larger than INT_MAX which may lead
>> integer overflow. We've fixed similar issue in the past during
>> qemu_net_queue_deliver_iov() by ignoring large packets there. Let's
>> just move the check earlier to qemu_sendv_packet_async() and reduce
>> the limitation to NET_BUFSIZE. A simple qtest were also added this.
>>
>> Please review.
> I did a test build and run, and the new test generates warning
> messages during "make check":
>    /ppc64/virtio/net/pci/large_tx:
> qemu-system-ppc64: warning: hub 0 is not connected to host network
> (similarly for /i386/ and /x86_64/).
>
> thank
> -- PMM

This is intended, we don't need any host networking device. This makes 
it very simpler and easier to trigger the queuing at hub. I can add a 
patch to suppress this warning if qtest is enabled.

Thanks