Re: [PATCH v5 6/7] tpm: ensure that the output of PCR read contains the correct digest size

[Roberto Sassu]

On 11/16/2018 2:41 PM, Jarkko Sakkinen wrote:
> On Wed, Nov 14, 2018 at 04:31:07PM +0100, Roberto Sassu wrote:
> > This patch protects against data corruption that could happen in the bus,
> > by checking that that the digest size returned by the TPM during a PCR read
> > matches the size of the algorithm passed to tpm2_pcr_read().
> >
> > This check is performed after information about the PCR banks has been
> > retrieved.
> >
> > Signed-off-by: Roberto Sassu <roberto.sassu@xxxxxxxxxx>
> > Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
> > Cc: stable@xxxxxxxxxxxxxxx
>
> Missing fixes tag.

Before this patch set, tpm2_pcr_extend() always copied 20 bytes from the
output sent by the TPM.

Roberto


> /Jarkko

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