Re: [Qemu-devel] [PATCH v4] aarch64: Allow -kernel option to take a gzip-compressed kernel.

[Peter Crosthwaite]

On Mon, Aug 4, 2014 at 6:48 PM, Richard W.M. Jones <address@hidden> wrote:
> 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 <address@hidden> 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.

Ok. If you really do need this artificial limit then I think you
should just make your own macro with the same value.

Regards,
Peter

> 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.
>
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