Re: [PATCH 2/8] pstore: Do not use crash buffer for decompression

From: Kees Cook
Date: Wed Nov 14 2018 - 02:56:17 EST


On Fri, Nov 2, 2018 at 1:24 PM, Joel Fernandes <joel@xxxxxxxxxxxxxxxxx> wrote:
> On Thu, Nov 01, 2018 at 04:51:54PM -0700, Kees Cook wrote:
>> static void decompress_record(struct pstore_record *record)
>> {
>> + int ret;
>> int unzipped_len;
>
> nit: We could get rid of the unzipped_len variable now I think.

I didn't follow this -- it gets used quite a bit. I don't see a clean
way to remove it?

>> + workspace = kmalloc(unzipped_len + record->ecc_notice_size,
>
> Should tihs be unzipped_len + record->ecc_notice_size + 1. The extra byte
> being for the NULL character of the ecc notice?
>
> This occurred to me when I saw the + 1 in ram.c. It could be better to just
> abstract the size as a macro.

Ooh, yes, good catch. I'll get this fixed.

Thanks for the review!

--
Kees Cook