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

[Jonathan McDowell <noodles@earth.li>]

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.

-- 
101 things you can't have too much of : 19 - A Good Thing.
This .sig brought to you by the letter V and the number 13
Product of the Republic of HuggieTag