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References: <20190208180857.12330-1-jarkko.sakkinen@linux.intel.com>
 <20190208180857.12330-2-jarkko.sakkinen@linux.intel.com> <20190209182022.zghnna3fa3a3x3w7@cantor>
In-Reply-To: <20190209182022.zghnna3fa3a3x3w7@cantor>
From:   Jerry Snitselaar <jsnitsel@redhat.com>
Date:   Sat, 9 Feb 2019 13:01:06 -0700
Message-ID: <CALzcddvbmjGHO4rjZ1udO7MuM3UPwuN4V43wxzMvPtnE2OusHg@mail.gmail.com>
Subject: Re: [PATCH v4 1/2] tpm: Unify the send callback behaviour
To:     Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc:     linux-integrity@vger.kernel.org,
        Linux List Kernel Mailing <linux-kernel@vger.kernel.org>,
        linux-security-module@vger.kernel.org,
        Peter Huewe <PeterHuewe@gmx.de>,
        Jason Gunthorpe <jgg@ziepe.ca>,
        Stefan Berger <stefanb@linux.vnet.ibm.com>,
        Alexander Steffen <Alexander.Steffen@infineon.com>,
        stable@vger.kernel.org
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Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Sat, Feb 9, 2019 at 11:20 AM Jerry Snitselaar <jsnitsel@redhat.com> wrote:
>
> On Fri Feb 08 19, Jarkko Sakkinen wrote:
> >The send() callback should never return length as it does not in every
> >driver except tpm_crb in the success case. The reason is that the main
> >transmit functionality only cares about whether the transmit was
> >successful or not and ignores the count completely.
> >
> >Cc: stable@vger.kernel.org
> >Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
> >---
> > drivers/char/tpm/st33zp24/st33zp24.c | 2 +-
> > drivers/char/tpm/tpm_atmel.c         | 2 +-
> > drivers/char/tpm/tpm_i2c_atmel.c     | 6 +++++-
> > drivers/char/tpm/tpm_i2c_infineon.c  | 2 +-
> > drivers/char/tpm/tpm_i2c_nuvoton.c   | 2 +-
> > drivers/char/tpm/tpm_ibmvtpm.c       | 8 ++++----
> > drivers/char/tpm/tpm_infineon.c      | 2 +-
> > drivers/char/tpm/tpm_nsc.c           | 2 +-
> > drivers/char/tpm/tpm_tis_core.c      | 2 +-
> > drivers/char/tpm/tpm_vtpm_proxy.c    | 3 +--
> > drivers/char/tpm/xen-tpmfront.c      | 2 +-
> > 11 files changed, 18 insertions(+), 15 deletions(-)
> >
> >diff --git a/drivers/char/tpm/st33zp24/st33zp24.c b/drivers/char/tpm/st33zp24/st33zp24.c
> >index 64dc560859f2..13dc614b7ebc 100644
> >--- a/drivers/char/tpm/st33zp24/st33zp24.c
> >+++ b/drivers/char/tpm/st33zp24/st33zp24.c
> >@@ -436,7 +436,7 @@ static int st33zp24_send(struct tpm_chip *chip, unsigned char *buf,
> >                       goto out_err;
> >       }
> >
> >-      return len;
> >+      return 0;
> > out_err:
> >       st33zp24_cancel(chip);
> >       release_locality(chip);
> >diff --git a/drivers/char/tpm/tpm_atmel.c b/drivers/char/tpm/tpm_atmel.c
> >index 66a14526aaf4..a290b30a0c35 100644
> >--- a/drivers/char/tpm/tpm_atmel.c
> >+++ b/drivers/char/tpm/tpm_atmel.c
> >@@ -105,7 +105,7 @@ static int tpm_atml_send(struct tpm_chip *chip, u8 *buf, size_t count)
> >               iowrite8(buf[i], priv->iobase);
> >       }
> >
> >-      return count;
> >+      return 0;
> > }
> >
> > static void tpm_atml_cancel(struct tpm_chip *chip)
> >diff --git a/drivers/char/tpm/tpm_i2c_atmel.c b/drivers/char/tpm/tpm_i2c_atmel.c
> >index 4720b2442ffe..aa11c8a1df5e 100644
> >--- a/drivers/char/tpm/tpm_i2c_atmel.c
> >+++ b/drivers/char/tpm/tpm_i2c_atmel.c
> >@@ -65,7 +65,11 @@ static int i2c_atmel_send(struct tpm_chip *chip, u8 *buf, size_t len)
> >       dev_dbg(&chip->dev,
> >               "%s(buf=%*ph len=%0zx) -> sts=%d\n", __func__,
> >               (int)min_t(size_t, 64, len), buf, len, status);
> >-      return status;
> >+
> >+      if (status < 0)
> >+              return status;
> >+
> >+      return 0;
> > }
> >
> > static int i2c_atmel_recv(struct tpm_chip *chip, u8 *buf, size_t count)
> >diff --git a/drivers/char/tpm/tpm_i2c_infineon.c b/drivers/char/tpm/tpm_i2c_infineon.c
> >index 3b490d9d90e7..3b4e9672ff6c 100644
> >--- a/drivers/char/tpm/tpm_i2c_infineon.c
> >+++ b/drivers/char/tpm/tpm_i2c_infineon.c
> >@@ -588,7 +588,7 @@ static int tpm_tis_i2c_send(struct tpm_chip *chip, u8 *buf, size_t len)
> >       /* go and do it */
> >       iic_tpm_write(TPM_STS(tpm_dev.locality), &sts, 1);
> >
> >-      return len;
> >+      return 0;
> > out_err:
> >       tpm_tis_i2c_ready(chip);
> >       /* The TPM needs some time to clean up here,
> >diff --git a/drivers/char/tpm/tpm_i2c_nuvoton.c b/drivers/char/tpm/tpm_i2c_nuvoton.c
> >index 5700cc2ddee1..315a3b4548f7 100644
> >--- a/drivers/char/tpm/tpm_i2c_nuvoton.c
> >+++ b/drivers/char/tpm/tpm_i2c_nuvoton.c
> >@@ -465,7 +465,7 @@ static int i2c_nuvoton_send(struct tpm_chip *chip, u8 *buf, size_t len)
> >       }
> >
> >       dev_dbg(dev, "%s() -> %zd\n", __func__, len);
> >-      return len;
> >+      return 0;
> > }
> >
> > static bool i2c_nuvoton_req_canceled(struct tpm_chip *chip, u8 status)
> >diff --git a/drivers/char/tpm/tpm_ibmvtpm.c b/drivers/char/tpm/tpm_ibmvtpm.c
> >index 07b5a487d0c8..757ca45b39b8 100644
> >--- a/drivers/char/tpm/tpm_ibmvtpm.c
> >+++ b/drivers/char/tpm/tpm_ibmvtpm.c
> >@@ -139,14 +139,14 @@ static int tpm_ibmvtpm_recv(struct tpm_chip *chip, u8 *buf, size_t count)
> > }
> >
> > /**
> >- * tpm_ibmvtpm_send - Send tpm request
> >- *
> >+ * tpm_ibmvtpm_send() - Send a TPM command
> >  * @chip:     tpm chip struct
> >  * @buf:      buffer contains data to send
> >  * @count:    size of buffer
> >  *
> >  * Return:
> >- *    Number of bytes sent or < 0 on error.
> >+ *   0 on success,
> >+ *   -errno on error
> >  */
> > static int tpm_ibmvtpm_send(struct tpm_chip *chip, u8 *buf, size_t count)
> > {
> >@@ -192,7 +192,7 @@ static int tpm_ibmvtpm_send(struct tpm_chip *chip, u8 *buf, size_t count)
> >               rc = 0;
> >               ibmvtpm->tpm_processing_cmd = false;
> >       } else
> >-              rc = count;
> >+              rc = 0;
> >
> >       spin_unlock(&ibmvtpm->rtce_lock);
> >       return rc;
> >diff --git a/drivers/char/tpm/tpm_infineon.c b/drivers/char/tpm/tpm_infineon.c
> >index d8f10047fbba..97f6d4fe0aee 100644
> >--- a/drivers/char/tpm/tpm_infineon.c
> >+++ b/drivers/char/tpm/tpm_infineon.c
> >@@ -354,7 +354,7 @@ static int tpm_inf_send(struct tpm_chip *chip, u8 * buf, size_t count)
> >       for (i = 0; i < count; i++) {
> >               wait_and_send(chip, buf[i]);
> >       }
> >-      return count;
> >+      return 0;
> > }
> >
> > static void tpm_inf_cancel(struct tpm_chip *chip)
> >diff --git a/drivers/char/tpm/tpm_nsc.c b/drivers/char/tpm/tpm_nsc.c
> >index 5d6cce74cd3f..9bee3c5eb4bf 100644
> >--- a/drivers/char/tpm/tpm_nsc.c
> >+++ b/drivers/char/tpm/tpm_nsc.c
> >@@ -226,7 +226,7 @@ static int tpm_nsc_send(struct tpm_chip *chip, u8 * buf, size_t count)
> >       }
> >       outb(NSC_COMMAND_EOC, priv->base + NSC_COMMAND);
> >
> >-      return count;
> >+      return 0;
> > }
> >
> > static void tpm_nsc_cancel(struct tpm_chip *chip)
> >diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
> >index 60e2038652b8..b9f64684c3fb 100644
> >--- a/drivers/char/tpm/tpm_tis_core.c
> >+++ b/drivers/char/tpm/tpm_tis_core.c
> >@@ -481,7 +481,7 @@ static int tpm_tis_send_main(struct tpm_chip *chip, const u8 *buf, size_t len)
> >                       goto out_err;
> >               }
> >       }
> >-      return len;
> >+      return 0;
> > out_err:
> >       tpm_tis_ready(chip);
> >       return rc;
> >diff --git a/drivers/char/tpm/tpm_vtpm_proxy.c b/drivers/char/tpm/tpm_vtpm_proxy.c
> >index 26a2be555288..d74f3de74ae6 100644
> >--- a/drivers/char/tpm/tpm_vtpm_proxy.c
> >+++ b/drivers/char/tpm/tpm_vtpm_proxy.c
> >@@ -335,7 +335,6 @@ static int vtpm_proxy_is_driver_command(struct tpm_chip *chip,
> > static int vtpm_proxy_tpm_op_send(struct tpm_chip *chip, u8 *buf, size_t count)
> > {
> >       struct proxy_dev *proxy_dev = dev_get_drvdata(&chip->dev);
> >-      int rc = 0;
> >
> >       if (count > sizeof(proxy_dev->buffer)) {
> >               dev_err(&chip->dev,
> >@@ -366,7 +365,7 @@ static int vtpm_proxy_tpm_op_send(struct tpm_chip *chip, u8 *buf, size_t count)
> >
> >       wake_up_interruptible(&proxy_dev->wq);
> >
> >-      return rc;
> >+      return 0;
> > }
> >
> > static void vtpm_proxy_tpm_op_cancel(struct tpm_chip *chip)
> >diff --git a/drivers/char/tpm/xen-tpmfront.c b/drivers/char/tpm/xen-tpmfront.c
> >index 1259e935fd58..4e2d00cb0d81 100644
> >--- a/drivers/char/tpm/xen-tpmfront.c
> >+++ b/drivers/char/tpm/xen-tpmfront.c
> >@@ -173,7 +173,7 @@ static int vtpm_send(struct tpm_chip *chip, u8 *buf, size_t count)
> >               return -ETIME;
> >       }
> >
> >-      return count;
> >+      return 0;
> > }
> >
> > static int vtpm_recv(struct tpm_chip *chip, u8 *buf, size_t count)
> >--
> >2.19.1
> >
>
> Does st33zp24_i2c_send need an update as well? It does 'return write8_reg()'.

Disregard this question. It is st33zp24_send that would be the one to
change, and you already dealt with that.