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

[Nayna <nayna@linux.vnet.ibm.com>]

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@linux.intel.com>
>>> ---
>>> 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
>