Re: [PATCH] tpm: fix byte order related arithmetic inconsistency in tpm_getcap()

From: Jason Gunthorpe
Date: Tue May 09 2017 - 11:13:22 EST


On Tue, May 09, 2017 at 05:13:53PM +0300, Jarkko Sakkinen wrote:
> On Sun, May 07, 2017 at 08:50:02PM +0300, Jarkko Sakkinen wrote:
> > You should not do arithmetic with __be32 or __le32 types because
> > sometimes it results incorrect results. Calculations must be done only
> > with integers that are in in the CPU byte order. This commit migrates
> > tpm_getcap() to struct tpm_buf in order to sort out these issues.
> >
> > Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
> > Now this should work as Robertos patches move byte order conversion
> > where it should be. Sadly I'm out of reach to my Dell E6400 laptop
> > that I use for TPM 1.2 testing.
> > drivers/char/tpm/tpm-interface.c | 30 ++++++++++++++++--------------
> > drivers/char/tpm/tpm.h | 13 -------------
> > 2 files changed, 16 insertions(+), 27 deletions(-)
>
> I've now tested this with TPM 1.2. Any complains?

Seems reasonable, but which linke had the problematic arithmetic?

Jason