Re: [PATCH] tpm: Fix TPM 1.2 Shutdown sequence to prevent future TPM operations

Jarkko Sakkinen
2019-06-14T15:15:18Z

On Thu, Jun 13, 2019 at 08:20:41AM -0700, Doug Anderson wrote:
> Found the patch in your tree at
> <http://git.infradead.org/users/jjs/linux-tpmdd.git/commit/41f15a4f02092d531fb34b42a06e9a1603a7df27>.
> I'm decidedly a non-expert here, mostly just wrangling a patch that
> someone else came up with. :-) ...but let's see...
>
> I think you're asking if the "Fixes" looks sane. I guess it depends
> on what you're trying to accomplish. Certainly what you've tagged in
> "Fixes" marks the point where it would be easiest to backport this fix
> to. ...but I think the problem is much older than that patch.
>
> As I understand it, this problem has existed for much longer. I
> believe that ${SUBJECT} patch evolved from an investigation that Luigi
> Semenzato did back in 2013 when we got back some Chromebooks whose
> TPMs claimed that they had been "attacked". Said another way, I
> believe it is an evolution of the patch <https://crrev.com/c/57988>
> ("CHROMIUM: workaround for Infineon TPM broken defensive timeout").
>
> ...so technically someone ought to want this on all old kernels.
> Maybe keep the "Cc: stable" but remove the "Fixes"?

I guess that is what we have to do then.

/Jarkko