Re: [tpmdd-devel] [PATCH] tpm: fix type issues in tpm_getcap()

[Nayna]

On 02/03/2017 11:45 PM, Jarkko Sakkinen wrote:
> On Fri, Feb 03, 2017 at 06:24:38PM +0530, Nayna wrote:
> > On 02/01/2017 11:23 PM, Jarkko Sakkinen wrote:
> > > There are two type issues associated with tpm_getcap().
> > >
> > > You must not do arithmetic with __be32 or __le32 types because sometimes
> > > it results incorrect results. Calculations must be done only with data
> > > that is in CPU byte order. This commit migrates tpm_getcap() to struct
> > > tpm_buf in order to sort out these issues.
> > >
> > > The second issue is with struct cap_t as the size of the type bool is
> > > assumed to be one byte. This commit sorts out the issue by changing the
> > > type to u8.
> > >
> > > Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
> > > ---
> > > v2:
> > > - Use struct tpm_buf.
> > > - Merge the type change of 'owned' to this patch.
> > >    drivers/char/tpm/tpm-interface.c | 33 ++++++++++++++++++---------------
> > >    drivers/char/tpm/tpm.h           | 15 +--------------
> > >    2 files changed, 19 insertions(+), 29 deletions(-)
> > >
> > > diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
> > > index 423938e..7af1e8c 100644
> > > --- a/drivers/char/tpm/tpm-interface.c
> > > +++ b/drivers/char/tpm/tpm-interface.c
> > > @@ -480,31 +480,34 @@ static const struct tpm_input_header tpm_getcap_header = {
> >
> > Is tpm_getcap_header still needed ?
>
> Definitely not, thanks. Are you able to try this out so I could
> move forward with pull request?

Yes, I tried it out and see a problem, I already replied that in one 
other mail.
The tag and ordinal are converted to BE twice, once in #define  and 
again in tpm_buf_init.

Thanks & Regards,
   - Nayna


> /Jarkko