[PATCH v3] tpm: Relocate buf->handles to appropriate place
Jarkko Sakkinen
jarkko at kernel.org
Wed Jul 17 09:34:26 UTC 2024
On Wed, 2024-07-17 at 12:31 +0300, Jarkko Sakkinen wrote:
> On Wed, 2024-07-17 at 12:27 +0300, Jarkko Sakkinen wrote:
> > On Tue, 2024-07-16 at 15:32 -0400, James Bottomley wrote:
> > > On Tue, 2024-07-16 at 21:52 +0300, Jarkko Sakkinen wrote:
> > > [...]
> > > > Further, 'handles' was incorrectly place to struct tpm_buf, as tpm-
> > > > buf.c does manage its state. It is easy to grep that only piece of
> > > > code that actually uses the field is tpm2-sessions.c.
> > > >
> > > > Address the issues by moving the variable to struct tpm_chip.
> > >
> > > That's really not a good idea, you should keep counts local to the
> > > structures they're counting, not elsewhere.
> > >
> > > tpm_buf->handles counts the number of handles present in the command
> > > encoded in a particular tpm_buf. Right at the moment we only ever
> > > construct one tpm_buf per tpm (i.e. per tpm_chip) at any one time, so
> > > you can get away with moving handles into tpm_chip. If we ever
> > > constructed more than one tpm_buf per chip, the handles count would
> > > become corrupted.
> >
> > It is not an idea. That count is in the wrong place. Buffer code
> > has no use for it.
>
> Also you are misleading here again. Depending on context tpm_buf
> stores different data, including handles.
These false claims can be also proved wrong by trivial git grep,
which clearly shows its scope.
BR, Jarkko
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