On Thu, 12 Dec 2019 at 23:28, James Bottomley
<James.Bottomley@xxxxxxxxxxxxxxxxxxxxx> wrote:
>
> The original code, before it was moved into security/keys/trusted-keys
> had a flush after the blob unseal. Without that flush, the volatile
> handles increase in the TPM until it becomes unusable and the system
> either has to be rebooted or the TPM volatile area manually flushed.
> Fix by adding back the lost flush, which we now have to export because
> of the relocation of the trusted key code may cause the consumer to be
> modular.
>
> Signed-off-by: James Bottomley <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx>
> Fixes: 2e19e10131a0 ("KEYS: trusted: Move TPM2 trusted keys code")
>
Overall looks good to me with following minor comment.
> ---
> drivers/char/tpm/tpm.h | 1 -
> drivers/char/tpm/tpm2-cmd.c | 1 +
> include/linux/tpm.h | 1 +
> security/keys/trusted-keys/trusted_tpm2.c | 1 +
> 4 files changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
> index b9e1547be6b5..5620747da0cf 100644
> --- a/drivers/char/tpm/tpm.h
> +++ b/drivers/char/tpm/tpm.h
> @@ -218,7 +218,6 @@ int tpm2_pcr_read(struct tpm_chip *chip, u32 pcr_idx,
> int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx,
> struct tpm_digest *digests);
> int tpm2_get_random(struct tpm_chip *chip, u8 *dest, size_t max);
> -void tpm2_flush_context(struct tpm_chip *chip, u32 handle);
> ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id,
> u32 *value, const char *desc);
>
> diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
> index fdb457704aa7..13696deceae8 100644
> --- a/drivers/char/tpm/tpm2-cmd.c
> +++ b/drivers/char/tpm/tpm2-cmd.c
> @@ -362,6 +362,7 @@ void tpm2_flush_context(struct tpm_chip *chip, u32 handle)
> tpm_transmit_cmd(chip, &buf, 0, "flushing context");
> tpm_buf_destroy(&buf);
> }
> +EXPORT_SYMBOL_GPL(tpm2_flush_context);
>
> struct tpm2_get_cap_out {
> u8 more_data;
> diff --git a/include/linux/tpm.h b/include/linux/tpm.h
> index 0d6e949ba315..03e9b184411b 100644
> --- a/include/linux/tpm.h
> +++ b/include/linux/tpm.h
> @@ -403,6 +403,7 @@ extern int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx,
> extern int tpm_send(struct tpm_chip *chip, void *cmd, size_t buflen);
> extern int tpm_get_random(struct tpm_chip *chip, u8 *data, size_t max);
> extern struct tpm_chip *tpm_default_chip(void);
> +void tpm2_flush_context(struct tpm_chip *chip, u32 handle);
Shouldn't this be declared as "extern" similar to other APIs? Also, I
think we need "#else" part for this API as well.
-Sumit
> #else
> static inline int tpm_is_tpm2(struct tpm_chip *chip)
> {
> diff --git a/security/keys/trusted-keys/trusted_tpm2.c b/security/keys/trusted-keys/trusted_tpm2.c
> index a9810ac2776f..08ec7f48f01d 100644
> --- a/security/keys/trusted-keys/trusted_tpm2.c
> +++ b/security/keys/trusted-keys/trusted_tpm2.c
> @@ -309,6 +309,7 @@ int tpm2_unseal_trusted(struct tpm_chip *chip,
> return rc;
>
> rc = tpm2_unseal_cmd(chip, payload, options, blob_handle);
> + tpm2_flush_context(chip, blob_handle);
>
> return rc;
> }
> --
> 2.16.4
>
