Re: [PATCH v8 08/17] tpm: call tpm2_flush_space() on error in tpm_try_transmit()

From: Sasha Levin
Date: Fri Nov 16 2018 - 11:20:00 EST


On Fri, Nov 16, 2018 at 02:38:32PM +0200, Jarkko Sakkinen wrote:
Always call tpm2_flush_space() on failure in tpm_try_transmit() so that
the volatile memory of the TPM gets cleared. If /dev/tpm0 does not have
sufficient permissions (usually it has), this could lead to the leakage
of TPM objects. Through /dev/tpmrm0 this issue does not raise any new
security concerns.

Cc: James Bottomley <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 745b361e989a ("tpm:tpm: infrastructure for TPM spaces")
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
Reviewed-by: Stefan Berger <stefanb@xxxxxxxxxxxxx>

Hi Jarkko,

This patch seems to depend on previous patches in this series, but those
were not tagged for stable. Do they also need to be backported? If so,
can you tag them as such?

--
Thanks,
Sasha