From mboxrd@z Thu Jan  1 00:00:00 1970
From: Avi Kivity <avi@redhat.com>
Subject: Re: [PATCH] KVM: Enhance the coalesced_mmio_write() parameter to
 avoid stack buffer overflow
Date: Mon, 12 Apr 2010 13:28:32 +0300
Message-ID: <4BC2F5D0.4090902@redhat.com>
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On 04/12/2010 04:57 AM, wzt.wzt@gmail.com wrote:
> coalesced_mmio_write() is not check the len value, if len is negative,
> memcpy(ring->coalesced_mmio[ring->last].data, val, len); will cause
> stack buffer overflow.
>
>    

How can len be negative?  It can only be between 1 and 8.

-- 
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.