Re: [PATCH] module: add in-kernel support for decompressing

From: Kees Cook
Date: Thu Dec 02 2021 - 03:14:25 EST


On Wed, Dec 01, 2021 at 12:19:08PM -0800, Dmitry Torokhov wrote:
> On Wed, Dec 01, 2021 at 11:24:35AM -0800, Kees Cook wrote:
> > On Sat, Nov 27, 2021 at 09:48:22PM -0800, Dmitry Torokhov wrote:
> > > /* Flags for sys_finit_module: */
> > > #define MODULE_INIT_IGNORE_MODVERSIONS 1
> > > #define MODULE_INIT_IGNORE_VERMAGIC 2
> > > +#define MODULE_INIT_COMPRESSED_DATA 4
> >
> > bikeshedding: adding "_DATA" seems redundant/misleading? The entire
> > module is compressed, so maybe call it just MODULE_INIT_COMPRESSED ?
>
> OK, or maybe MODULE_INIT_COMPRESSED_FILE since we are indeed dealing
> with a file?

Sounds good to me! :)

As far as my tangent on using the crypto subsystem, I think that looks
like a long path, so your existing routines are likely the right place
to start. I still wonder if it might be able to use of the "acomp" API
instead of calling directly into the specific decompressor.

--
Kees Cook