From: Jarkko Sakkinen <jarkko.sakkinen@opinsys.com>
Open code tpm_buf_append_hmac_session_opt() in order to unmask the code
paths in the call sites of tpm_buf_append_hmac_session().
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@opinsys.com>
---
v3:
- No changes.
v2:
- Uncorrupt the patch.
---
drivers/char/tpm/tpm2-cmd.c | 14 +++++++++++---
include/linux/tpm.h | 23 -----------------------
security/keys/trusted-keys/trusted_tpm2.c | 12 ++++++++++--
3 files changed, 21 insertions(+), 28 deletions(-)
diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
index 86b1a4d859b9..c7bfa705ea8f 100644
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -257,9 +257,17 @@ int tpm2_get_random(struct tpm_chip *chip, u8 *dest, size_t max)
do {
tpm_buf_reset(&buf, TPM2_ST_SESSIONS, TPM2_CC_GET_RANDOM);
- tpm_buf_append_hmac_session_opt(chip, &buf, TPM2_SA_ENCRYPT
- | TPM2_SA_CONTINUE_SESSION,
- NULL, 0);
+ if (tpm2_chip_auth(chip)) {
+ tpm_buf_append_hmac_session(chip, &buf,
+ TPM2_SA_ENCRYPT |
+ TPM2_SA_CONTINUE_SESSION,
+ NULL, 0);
+ } else {
+ offset = buf.handles * 4 + TPM_HEADER_SIZE;
+ head = (struct tpm_header *)buf.data;
+ if (tpm_buf_length(&buf) == offset)
+ head->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS);
+ }
tpm_buf_append_u16(&buf, num_bytes);
tpm_buf_fill_hmac_session(chip, &buf);
err = tpm_transmit_cmd(chip, &buf,
diff --git a/include/linux/tpm.h b/include/linux/tpm.h
index 1fa02e18e688..e72e7657faa2 100644
--- a/include/linux/tpm.h
+++ b/include/linux/tpm.h
@@ -532,29 +532,6 @@ void tpm_buf_append_hmac_session(struct tpm_chip *chip, struct tpm_buf *buf,
int passphraselen);
void tpm_buf_append_auth(struct tpm_chip *chip, struct tpm_buf *buf,
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);
- }
-}
#ifdef CONFIG_TCG_TPM2_HMAC
diff --git a/security/keys/trusted-keys/trusted_tpm2.c b/security/keys/trusted-keys/trusted_tpm2.c
index e165b117bbca..c414a7006d78 100644
--- a/security/keys/trusted-keys/trusted_tpm2.c
+++ b/security/keys/trusted-keys/trusted_tpm2.c
@@ -482,8 +482,10 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
struct trusted_key_options *options,
u32 blob_handle)
{
+ struct tpm_header *head;
struct tpm_buf buf;
u16 data_len;
+ int offset;
u8 *data;
int rc;
@@ -518,8 +520,14 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
tpm2_buf_append_auth(&buf, options->policyhandle,
NULL /* nonce */, 0, 0,
options->blobauth, options->blobauth_len);
- tpm_buf_append_hmac_session_opt(chip, &buf, TPM2_SA_ENCRYPT,
- NULL, 0);
+ if (tpm2_chip_auth(chip)) {
+ tpm_buf_append_hmac_session(chip, &buf, TPM2_SA_ENCRYPT, NULL, 0);
+ } else {
+ offset = buf.handles * 4 + TPM_HEADER_SIZE;
+ head = (struct tpm_header *)buf.data;
+ if (tpm_buf_length(&buf) == offset)
+ head->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS);
+ }
}
tpm_buf_fill_hmac_session(chip, &buf);
--
2.39.5
On Mon, Sep 29, 2025 at 10:48:27PM +0300, Jarkko Sakkinen wrote:
> From: Jarkko Sakkinen <jarkko.sakkinen@opinsys.com>
>
> Open code tpm_buf_append_hmac_session_opt() in order to unmask the code
> paths in the call sites of tpm_buf_append_hmac_session().
>
> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@opinsys.com>
Reviewed-by: Jonathan McDowell <noodles@meta.com>
> ---
> v3:
> - No changes.
> v2:
> - Uncorrupt the patch.
> ---
> drivers/char/tpm/tpm2-cmd.c | 14 +++++++++++---
> include/linux/tpm.h | 23 -----------------------
> security/keys/trusted-keys/trusted_tpm2.c | 12 ++++++++++--
> 3 files changed, 21 insertions(+), 28 deletions(-)
>
> diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
> index 86b1a4d859b9..c7bfa705ea8f 100644
> --- a/drivers/char/tpm/tpm2-cmd.c
> +++ b/drivers/char/tpm/tpm2-cmd.c
> @@ -257,9 +257,17 @@ int tpm2_get_random(struct tpm_chip *chip, u8 *dest, size_t max)
>
> do {
> tpm_buf_reset(&buf, TPM2_ST_SESSIONS, TPM2_CC_GET_RANDOM);
> - tpm_buf_append_hmac_session_opt(chip, &buf, TPM2_SA_ENCRYPT
> - | TPM2_SA_CONTINUE_SESSION,
> - NULL, 0);
> + if (tpm2_chip_auth(chip)) {
> + tpm_buf_append_hmac_session(chip, &buf,
> + TPM2_SA_ENCRYPT |
> + TPM2_SA_CONTINUE_SESSION,
> + NULL, 0);
> + } else {
> + offset = buf.handles * 4 + TPM_HEADER_SIZE;
> + head = (struct tpm_header *)buf.data;
> + if (tpm_buf_length(&buf) == offset)
> + head->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS);
> + }
> tpm_buf_append_u16(&buf, num_bytes);
> tpm_buf_fill_hmac_session(chip, &buf);
> err = tpm_transmit_cmd(chip, &buf,
> diff --git a/include/linux/tpm.h b/include/linux/tpm.h
> index 1fa02e18e688..e72e7657faa2 100644
> --- a/include/linux/tpm.h
> +++ b/include/linux/tpm.h
> @@ -532,29 +532,6 @@ void tpm_buf_append_hmac_session(struct tpm_chip *chip, struct tpm_buf *buf,
> int passphraselen);
> void tpm_buf_append_auth(struct tpm_chip *chip, struct tpm_buf *buf,
> 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);
> - }
> -}
>
> #ifdef CONFIG_TCG_TPM2_HMAC
>
> diff --git a/security/keys/trusted-keys/trusted_tpm2.c b/security/keys/trusted-keys/trusted_tpm2.c
> index e165b117bbca..c414a7006d78 100644
> --- a/security/keys/trusted-keys/trusted_tpm2.c
> +++ b/security/keys/trusted-keys/trusted_tpm2.c
> @@ -482,8 +482,10 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
> struct trusted_key_options *options,
> u32 blob_handle)
> {
> + struct tpm_header *head;
> struct tpm_buf buf;
> u16 data_len;
> + int offset;
> u8 *data;
> int rc;
>
> @@ -518,8 +520,14 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
> tpm2_buf_append_auth(&buf, options->policyhandle,
> NULL /* nonce */, 0, 0,
> options->blobauth, options->blobauth_len);
> - tpm_buf_append_hmac_session_opt(chip, &buf, TPM2_SA_ENCRYPT,
> - NULL, 0);
> + if (tpm2_chip_auth(chip)) {
> + tpm_buf_append_hmac_session(chip, &buf, TPM2_SA_ENCRYPT, NULL, 0);
> + } else {
> + offset = buf.handles * 4 + TPM_HEADER_SIZE;
> + head = (struct tpm_header *)buf.data;
> + if (tpm_buf_length(&buf) == offset)
> + head->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS);
> + }
> }
>
> tpm_buf_fill_hmac_session(chip, &buf);
> --
> 2.39.5
>
>
J.
--
... I love you the way a bomb loves a crowd.
On Tue, Sep 30, 2025 at 12:11:47PM +0100, Jonathan McDowell wrote:
> On Mon, Sep 29, 2025 at 10:48:27PM +0300, Jarkko Sakkinen wrote:
> > From: Jarkko Sakkinen <jarkko.sakkinen@opinsys.com>
> >
> > Open code tpm_buf_append_hmac_session_opt() in order to unmask the code
> > paths in the call sites of tpm_buf_append_hmac_session().
> >
> > Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@opinsys.com>
>
> Reviewed-by: Jonathan McDowell <noodles@meta.com>
Thanks (short summary has a typo tho)
>
> > ---
> > v3:
> > - No changes.
> > v2:
> > - Uncorrupt the patch.
> > ---
> > drivers/char/tpm/tpm2-cmd.c | 14 +++++++++++---
> > include/linux/tpm.h | 23 -----------------------
> > security/keys/trusted-keys/trusted_tpm2.c | 12 ++++++++++--
> > 3 files changed, 21 insertions(+), 28 deletions(-)
> >
> > diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
> > index 86b1a4d859b9..c7bfa705ea8f 100644
> > --- a/drivers/char/tpm/tpm2-cmd.c
> > +++ b/drivers/char/tpm/tpm2-cmd.c
> > @@ -257,9 +257,17 @@ int tpm2_get_random(struct tpm_chip *chip, u8 *dest, size_t max)
> >
> > do {
> > tpm_buf_reset(&buf, TPM2_ST_SESSIONS, TPM2_CC_GET_RANDOM);
> > - tpm_buf_append_hmac_session_opt(chip, &buf, TPM2_SA_ENCRYPT
> > - | TPM2_SA_CONTINUE_SESSION,
> > - NULL, 0);
> > + if (tpm2_chip_auth(chip)) {
> > + tpm_buf_append_hmac_session(chip, &buf,
> > + TPM2_SA_ENCRYPT |
> > + TPM2_SA_CONTINUE_SESSION,
> > + NULL, 0);
> > + } else {
> > + offset = buf.handles * 4 + TPM_HEADER_SIZE;
> > + head = (struct tpm_header *)buf.data;
> > + if (tpm_buf_length(&buf) == offset)
> > + head->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS);
> > + }
> > tpm_buf_append_u16(&buf, num_bytes);
> > tpm_buf_fill_hmac_session(chip, &buf);
> > err = tpm_transmit_cmd(chip, &buf,
> > diff --git a/include/linux/tpm.h b/include/linux/tpm.h
> > index 1fa02e18e688..e72e7657faa2 100644
> > --- a/include/linux/tpm.h
> > +++ b/include/linux/tpm.h
> > @@ -532,29 +532,6 @@ void tpm_buf_append_hmac_session(struct tpm_chip *chip, struct tpm_buf *buf,
> > int passphraselen);
> > void tpm_buf_append_auth(struct tpm_chip *chip, struct tpm_buf *buf,
> > 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);
> > - }
> > -}
> >
> > #ifdef CONFIG_TCG_TPM2_HMAC
> >
> > diff --git a/security/keys/trusted-keys/trusted_tpm2.c b/security/keys/trusted-keys/trusted_tpm2.c
> > index e165b117bbca..c414a7006d78 100644
> > --- a/security/keys/trusted-keys/trusted_tpm2.c
> > +++ b/security/keys/trusted-keys/trusted_tpm2.c
> > @@ -482,8 +482,10 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
> > struct trusted_key_options *options,
> > u32 blob_handle)
> > {
> > + struct tpm_header *head;
> > struct tpm_buf buf;
> > u16 data_len;
> > + int offset;
> > u8 *data;
> > int rc;
> >
> > @@ -518,8 +520,14 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
> > tpm2_buf_append_auth(&buf, options->policyhandle,
> > NULL /* nonce */, 0, 0,
> > options->blobauth, options->blobauth_len);
> > - tpm_buf_append_hmac_session_opt(chip, &buf, TPM2_SA_ENCRYPT,
> > - NULL, 0);
> > + if (tpm2_chip_auth(chip)) {
> > + tpm_buf_append_hmac_session(chip, &buf, TPM2_SA_ENCRYPT, NULL, 0);
> > + } else {
> > + offset = buf.handles * 4 + TPM_HEADER_SIZE;
> > + head = (struct tpm_header *)buf.data;
> > + if (tpm_buf_length(&buf) == offset)
> > + head->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS);
> > + }
> > }
> >
> > tpm_buf_fill_hmac_session(chip, &buf);
> > --
> > 2.39.5
> >
> >
>
> J.
>
> --
> ... I love you the way a bomb loves a crowd.
BR, Jarkko
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