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Date: Thu, 20 Nov 2014 16:05:09 +0800
From: Gonglei <arei.gonglei@huawei.com>
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Subject: Re: [Qemu-devel] [PATCH 4/4] rtl8139: fix Pointer to local outside
 scope
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To: Jason Wang <jasowang@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>, "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>, "stefanha@redhat.com" <stefanha@redhat.com>, "Huangpeng (Peter)" <peter.huangpeng@huawei.com>

On 2014/11/20 15:50, Jason Wang wrote:

>>> Maybe just initialize iov unconditionally at the beginning and check
>>> >> dot1q_buf instead of iov for the rest of the functions. (Need deal with
>>> >> size < ETHER_ADDR_LEN * 2)
>> > More complicated, because we can't initialize iov when
>> >  "size < ETHER_ADDR_LEN * 2".
>> >
>> > Best regards,
>> > -Gonglei
>> >
> Probably not: you can just do something like:
> 
>     if (dot1q_buf && size < ETHER_ADDR_LEN * 2) {
>         dot1q_buf = NULL;
>     }
> 
> and check dot1q_buf afterwards. Or just drop the packet since its size
> was less than mininum frame length that Ethernet allows.

Sorry, I don't understand. But,
what's your meaning "initialize iov unconditionally at the beginning"?

Best regards,
-Gonglei