On Mon, Jan 12, 2026 at 04:22:24PM -0800, [email protected] wrote:
> On 12/14/25 7:38 AM, Jarkko Sakkinen wrote:
> > In all of the call sites only one session is ever append. Thus, reduce
> > AUTH_MAX_NAMES, which leads into removing constant completely.
> >
> > Signed-off-by: Jarkko Sakkinen <[email protected]>
> > ---
> > drivers/char/tpm/tpm2-sessions.c | 31 +++++++++++--------------------
> > 1 file changed, 11 insertions(+), 20 deletions(-)
> >
> > diff --git a/drivers/char/tpm/tpm2-sessions.c
> > b/drivers/char/tpm/tpm2-sessions.c
> > index 3bc3c31cf512..37570dc088cf 100644
> > --- a/drivers/char/tpm/tpm2-sessions.c
> > +++ b/drivers/char/tpm/tpm2-sessions.c
> > @@ -72,9 +72,6 @@
> > #include <crypto/sha2.h>
> > #include <crypto/utils.h>
> > -/* maximum number of names the TPM must remember for authorization */
> > -#define AUTH_MAX_NAMES 3
> > -
> > #define AES_KEY_BYTES AES_KEYSIZE_128
> > #define AES_KEY_BITS (AES_KEY_BYTES*8)
> > @@ -136,8 +133,8 @@ struct tpm2_auth {
> > * handle, but they are part of the session by name, which
> > * we must compute and remember
> > */
> > - u8 name[AUTH_MAX_NAMES][TPM2_MAX_NAME_SIZE];
> > - u16 name_size_tbl[AUTH_MAX_NAMES];
> > + u8 name[TPM2_MAX_NAME_SIZE];
> > + u16 name_size;
> > };
> > #ifdef CONFIG_TCG_TPM2_HMAC
> > @@ -261,11 +258,14 @@ EXPORT_SYMBOL_GPL(tpm2_read_public);
> > int tpm_buf_append_name(struct tpm_chip *chip, struct tpm_buf *buf,
> > u32 handle, u8 *name, u16 name_size)
> > {
> > -#ifdef CONFIG_TCG_TPM2_HMAC
>
> Removing CONFIG_TCG_TPM2_HMAC here causes a warning during compile since the
> auth variable is only used in the CONFIG_TCG_TPM2_HMAC block below.
Thanks for the remark, I'll look into this.
I should have next week bandwidth to look into your patch set too (still
rebooting from the holidays)
>
> Ross
>
> > struct tpm2_auth *auth;
> > - int slot;
> > int ret;
> > -#endif
> > +
> > + if (tpm_buf_length(buf) != TPM_HEADER_SIZE) {
> > + dev_err(&chip->dev, "too many handles\n");
> > + ret = -EIO;
> > + goto err;
> > + }
> > if (!tpm2_chip_auth(chip)) {
> > tpm_buf_append_handle(chip, buf, handle);
> > @@ -273,12 +273,6 @@ int tpm_buf_append_name(struct tpm_chip *chip, struct
> > tpm_buf *buf,
> > }
> > #ifdef CONFIG_TCG_TPM2_HMAC
> > - slot = (tpm_buf_length(buf) - TPM_HEADER_SIZE) / 4;
> > - if (slot >= AUTH_MAX_NAMES) {
> > - dev_err(&chip->dev, "too many handles\n");
> > - ret = -EIO;
> > - goto err;
> > - }
> > auth = chip->auth;
> > if (auth->session != tpm_buf_length(buf)) {
> > dev_err(&chip->dev, "session state malformed");
> > @@ -287,16 +281,14 @@ int tpm_buf_append_name(struct tpm_chip *chip, struct
> > tpm_buf *buf,
> > }
> > tpm_buf_append_u32(buf, handle);
> > auth->session += 4;
> > - memcpy(auth->name[slot], name, name_size);
> > - auth->name_size_tbl[slot] = name_size;
> > + memcpy(auth->name, name, name_size);
> > + auth->name_size = name_size;
> > #endif
> > return 0;
> > -#ifdef CONFIG_TCG_TPM2_HMAC
> > err:
> > tpm2_end_auth_session(chip);
> > return ret;
> > -#endif
> > }
> > EXPORT_SYMBOL_GPL(tpm_buf_append_name);
> > @@ -665,8 +657,7 @@ int tpm_buf_fill_hmac_session(struct tpm_chip *chip,
> > struct tpm_buf *buf)
> > /* ordinal is already BE */
> > sha256_update(&sctx, (u8 *)&head->ordinal, sizeof(head->ordinal));
> > /* add the handle names */
> > - for (i = 0; i < handles; i++)
> > - sha256_update(&sctx, auth->name[i], auth->name_size_tbl[i]);
> > + sha256_update(&sctx, auth->name, auth->name_size);
> > if (offset_s != tpm_buf_length(buf))
> > sha256_update(&sctx, &buf->data[offset_s],
> > tpm_buf_length(buf) - offset_s);
>
BR, Jarkko
