Re: [coreboot] [PATCH] Re: LZMA magic number

[Myles Watson]

> -----Original Message-----
> From: [e-mail] [mailto:[e-mail]]
> On Behalf Of Ward Vandewege
> Sent: Wednesday, August 27, 2008 3:02 PM
> To: Carl-Daniel Hailfinger
> Cc: [e-mail]
> Subject: [coreboot] [PATCH] Re: LZMA magic number
>
> On Sat, Jan 26, 2008 at 02:18:39AM +0100, Carl-Daniel Hailfinger wrote:
> > On 25.01.2008 18:58, Peter Stuge wrote:
> > > On Fri, Jan 25, 2008 at 10:55:24AM -0700, Myles Watson wrote:
> > > > I accidentally used an uncompressed payload with v2 when it
> > > > expected a compressed payload, and it gave me the message:
> > > >    Decoder scratchpad too small!!
> > > >    Decoding error = 1
> > >
> > > I got this too.
> > > > I think it would be nicer to have an error like:
> > > >    Payload not compressed with lzma!
> > >
> > > And we can check it already at build time.
> >
> > LZMA compressed payloads to not have a magic number, all you can do is
> > check if the header parameters are in a reasonable range. Sorry.
> > This problem fortunately does not exist in v3 because LAR does the
> > compression itself and notes the compression type in th header.
>
> I ran into this runtime error as well today.
>
> Please find a patch attached that makes coreboot a bit smarter in dealing
> with this situation, and avoids the fatal runtime error.

Ward,

I like the idea of assuming no compression if uncompressing it fails.  I
wonder if it would be better to copy it to dest instead of running it in
place.

Thanks,
Myles