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From: Markus Armbruster <armbru@redhat.com>
References: <20170728123127.27921-1-olaf@aepfle.de>
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Date: Fri, 28 Jul 2017 18:35:57 +0200
In-Reply-To: <20170728124832.GP8603@aepfle.de> (Olaf Hering's message of "Fri,
	28 Jul 2017 14:48:33 +0200")
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Subject: Re: [Qemu-devel] [PATCH] xen-disk: use g_malloc0 to fix build
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To: Olaf Hering <olaf@aepfle.de>
Cc: Eric Blake <eblake@redhat.com>, Kevin Wolf <kwolf@redhat.com>, Stefano Stabellini <sstabellini@kernel.org>, "open list:Block layer core" <qemu-block@nongnu.org>, "open list:All patches CC here" <qemu-devel@nongnu.org>, Max Reitz <mreitz@redhat.com>, Anthony Perard <anthony.perard@citrix.com>, "open list:X86" <xen-devel@lists.xenproject.org>

Olaf Hering <olaf@aepfle.de> writes:

> On Fri, Jul 28, Eric Blake wrote:
>
>> This version is prone to multiplication overflow (well, maybe not, but
>> you have to audit for that).  Wouldn't it be better to use:
>
> What could go wrong?
> qemu will die either way, I think.

An overflow in the size argument of malloc(), realloc(), etc. is a heap
overrun waiting to happen.