RE: [GIT PULL] integrity subsystem updates for v5.8

[Roberto Sassu]

> From: linux-integrity-owner@xxxxxxxxxxxxxxx [mailto:linux-integrity-
> owner@xxxxxxxxxxxxxxx] On Behalf Of Linus Torvalds
> Sent: Sunday, June 7, 2020 9:59 PM
> On Fri, Jun 5, 2020 at 10:03 AM Mimi Zohar <zohar@xxxxxxxxxxxxx> wrote:
> >
> > The main changes are extending the TPM 2.0 PCR banks with bank
> > specific file hashes, calculating the "boot_aggregate" based on other
> > TPM PCR banks, using the default IMA hash algorithm, instead of SHA1,
> > as the basis for the cache hash table key, and preventing the mprotect
> > syscall to circumvent an IMA mmap appraise policy rule.
> 
> I'm not sure why I didn't notice this during my test builds, but this
> results in a new warning:
> 
>   WARNING: modpost: vmlinux.o(.text+0x496264): Section mismatch in
> reference from the function ima_calc_boot_aggregate() to the function
> .init.text:ima_pcrread()
>   The function ima_calc_boot_aggregate() references
>   the function __init ima_pcrread().
>   This is often because ima_calc_boot_aggregate lacks a __init
>   annotation or the annotation of ima_pcrread is wrong.
> 
> and I think the warning is real - and the problem is real, not just a
> missing annotation.
> 
> It looks like ima_calc_boot_aggregate() may be called not only at init
> time (ima_eventdigest_init() is referenced from "struct
> ima_template_field supported_fields[]", for example)
> 
> So calling an __init function would be very wrong, because it might be
> gone by that time.
> 
> Hmm?

Right, I also missed it. Will send a patch soon.

Roberto

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