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Date: Mon, 4 Aug 2014 09:48:44 +0100
From: "Richard W.M. Jones" <rjones@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH v4] aarch64: Allow -kernel option to take a
 gzip-compressed kernel.
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To: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Cc: Peter Maydell <peter.maydell@linaro.org>, "qemu-devel@nongnu.org Developers" <qemu-devel@nongnu.org>

On Mon, Aug 04, 2014 at 09:05:39AM +1000, Peter Crosthwaite wrote:
> On Sun, Aug 3, 2014 at 1:45 AM, Richard W.M. Jones <rjones@redhat.com> wrote:
> > +    max_bytes = UBOOT_MAX_GUNZIP_BYTES;
> 
> Why does u-boot's maximum size limit apply here?

We need some maximum to prevent people uploading a kernel (perhaps
from an untrusted source) which is some sort of malicious gzip file
that expands to a huge size.

In this case the u-boot limit is 64 MB which is larger than most
possible kernels, so it seemed like a reasonable limit to choose.
You're right there is no connection to u-boot, except that both the
-kernel option and u-boot have similar concerns with maximum kernel
size, and presumably the u-boot limit is battle-tested.

I'll split the patch into two and send v5 soon.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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