Re: [PATCH v3 2/6] tpm: Store TPM buffer length

From: Jarkko Sakkinen
Date: Wed Nov 15 2023 - 16:05:03 EST


On Mon Nov 6, 2023 at 9:36 PM EET, Jerry Snitselaar wrote:
> On Tue, Oct 24, 2023 at 04:15:20AM +0300, Jarkko Sakkinen wrote:
> > Both TPM commands and sized buffers (TPM2B) have a fixed size header, which
> > is followed by the body. Store TPM buffer length to a new field in the
> > struct tpm_buf.
> >
> > The invariant here is that the length field must always contain the total
> > length of the buffer, i.e. the sum header and body length. The value must
> > then be mapped to the length representation of the buffer type, and this
> > correspondence must be maintained.
> >
> > Signed-off-by: Jarkko Sakkinen <jarkko@xxxxxxxxxx>
> > ---
> > drivers/char/tpm/tpm-buf.c | 36 ++++++++++++++++-------
> > drivers/char/tpm/tpm-interface.c | 18 +++++++++---
> > include/linux/tpm.h | 10 +++----
> > security/keys/trusted-keys/trusted_tpm1.c | 8 ++---
> > 4 files changed, 49 insertions(+), 23 deletions(-)
> >
> > diff --git a/drivers/char/tpm/tpm-buf.c b/drivers/char/tpm/tpm-buf.c
> > index 88ce1a5402de..8dc6b9db006b 100644
> > --- a/drivers/char/tpm/tpm-buf.c
> > +++ b/drivers/char/tpm/tpm-buf.c
> > @@ -18,6 +18,12 @@ int tpm_buf_init(struct tpm_buf *buf, u16 tag, u32 ordinal)
> > }
> > EXPORT_SYMBOL_GPL(tpm_buf_init);
> >
> > +/**
> > + * tpm_buf_reset() - Initialize a TPM command
> > + * @buf: A @tpm_buf
>
> One minor thing I meant to mention, did you intend this to be &tpm_buf like it
> is for tpm_buf_append?

Yep, thanks. I'll change it to &tpm_buf.

BR, Jarkko