Re: [PATCH 2/4] tpm2-sessions: Remove unused parameter from tpm_buf_append_auth

Jonathan McDowell
2025-09-24T08:48:10Z

On Mon, Sep 22, 2025 at 07:43:15PM +0300, Jarkko Sakkinen wrote:
>From: Jarkko Sakkinen <jarkko.sakkinen@opinsys.com>
>
>In earlier bug fix, an extra parameter was by mistake to the function.
>
>Fixes: 27184f8905ba ("tpm: Opt-in in disable PCR integrity protection")
>Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@opinsys.com>
>---
> drivers/char/tpm/tpm2-cmd.c | 2 +-
> drivers/char/tpm/tpm2-sessions.c | 5 ++---
> include/linux/tpm.h | 25 +------------------------
> 3 files changed, 4 insertions(+), 28 deletions(-)
>
>diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
>index 7d77f6fbc152..61a4daaef292 100644
>--- a/drivers/char/tpm/tpm2-cmd.c
>+++ b/drivers/char/tpm/tpm2-cmd.c
>@@ -191,7 +191,7 @@ int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx,
> tpm_buf_append_hmac_session(chip, &buf, 0, NULL, 0);
> } else {
> tpm_buf_append_handle(chip, &buf, pcr_idx);
>- tpm_buf_append_auth(chip, &buf, 0, NULL, 0);
>+ tpm_buf_append_auth(chip, &buf, NULL, 0);
> }
>
> tpm_buf_append_u32(&buf, chip->nr_allocated_banks);
>diff --git a/drivers/char/tpm/tpm2-sessions.c b/drivers/char/tpm/tpm2-sessions.c
>index 6d03c224e6b2..13f019d1312a 100644
>--- a/drivers/char/tpm/tpm2-sessions.c
>+++ b/drivers/char/tpm/tpm2-sessions.c
>@@ -266,7 +266,7 @@ void tpm_buf_append_name(struct tpm_chip *chip, struct tpm_buf *buf,
> EXPORT_SYMBOL_GPL(tpm_buf_append_name);
>
> void tpm_buf_append_auth(struct tpm_chip *chip, struct tpm_buf *buf,
>- u8 attributes, u8 *passphrase, int passphrase_len)
>+ u8 *passphrase, int passphrase_len)
> {
> /* offset tells us where the sessions area begins */
> int offset = buf->handles * 4 + TPM_HEADER_SIZE;
>@@ -327,8 +327,7 @@ void tpm_buf_append_hmac_session(struct tpm_chip *chip, struct tpm_buf *buf,
> #endif
>
> if (!tpm2_chip_auth(chip)) {
>- tpm_buf_append_auth(chip, buf, attributes, passphrase,
>- passphrase_len);
>+ tpm_buf_append_auth(chip, buf, passphrase, passphrase_len);
> return;
> }

This chunk below should be in patch 3/4 where you open code
tpm_buf_append_hmac_session_opt, rather than here:

>diff --git a/include/linux/tpm.h b/include/linux/tpm.h
>index 667d290789ca..a8984d273c28 100644
>--- a/include/linux/tpm.h
>+++ b/include/linux/tpm.h
>@@ -533,30 +533,7 @@ void tpm_buf_append_hmac_session(struct tpm_chip *chip, struct tpm_buf *buf,
> u8 attributes, u8 *passphrase,
> int passphraselen);
> void tpm_buf_append_auth(struct tpm_chip *chip, struct tpm_buf *buf,
>- u8 attributes, u8 *passphrase, int passphraselen);
>-static inline void tpm_buf_append_hmac_session_opt(struct tpm_chip *chip,
>- struct tpm_buf *buf,
>- u8 attributes,
>- u8 *passphrase,
>- int passphraselen)
>-{
>- struct tpm_header *head;
>- int offset;
>-
>- if (tpm2_chip_auth(chip)) {
>- tpm_buf_append_hmac_session(chip, buf, attributes, passphrase, passphraselen);
>- } else {
>- offset = buf->handles * 4 + TPM_HEADER_SIZE;
>- head = (struct tpm_header *)buf->data;
>-
>- /*
>- * If the only sessions are optional, the command tag must change to
>- * TPM2_ST_NO_SESSIONS.
>- */
>- if (tpm_buf_length(buf) == offset)
>- head->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS);
>- }
>-}
>+ u8 *passphrase, int passphraselen);
>
> #ifdef CONFIG_TCG_TPM2_HMAC
>
>--
>2.39.5
>
>

J.

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