Commit 3c1701339284353c41 ("tpm: Keep CLKRUN enabled throughout
the duration of transmit_cmd()") added code which accessed
chip->ops, even after it was set to NULL in tpm_del_char_device(),
called from tpm_chip_unregister() in error / driver exit paths.
So fix this code.
Fixes: 3c1701339284353c41 ("tpm: Keep CLKRUN enabled throughout
the duration of transmit_cmd()")
Suggested-by: Javier Martinez Canillas <[email protected]>
Suggested-by: Jason Gunthorpe <[email protected]>
Signed-off-by: Azhar Shaikh <[email protected]>
---
drivers/char/tpm/tpm-chip.c | 5 +++++
drivers/char/tpm/tpm.h | 1 +
drivers/char/tpm/tpm_tis.c | 8 ++------
drivers/char/tpm/tpm_tis_core.c | 23 +++++++++++++++--------
drivers/char/tpm/tpm_tis_spi.c | 1 +
5 files changed, 24 insertions(+), 14 deletions(-)
diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
index 0a62c19937b6..c88ec9a32a7e 100644
--- a/drivers/char/tpm/tpm-chip.c
+++ b/drivers/char/tpm/tpm-chip.c
@@ -346,6 +346,10 @@ static void tpm_del_char_device(struct tpm_chip *chip)
down_write(&chip->ops_sem);
if (chip->flags & TPM_CHIP_FLAG_TPM2)
tpm2_shutdown(chip, TPM2_SU_CLEAR);
+ if (chip->flags & TPM_CHIP_FLAG_DO_NOT_CLEAR_OPS) {
+ up_write(&chip->ops_sem);
+ return;
+ }
chip->ops = NULL;
up_write(&chip->ops_sem);
}
@@ -454,6 +458,7 @@ int tpm_chip_register(struct tpm_chip *chip)
rc = tpm_add_legacy_sysfs(chip);
if (rc) {
+ chip->flags |= TPM_CHIP_FLAG_DO_NOT_CLEAR_OPS;
tpm_chip_unregister(chip);
return rc;
}
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index f895fba4e20d..dc2a532649e0 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -183,6 +183,7 @@ enum tpm_chip_flags {
TPM_CHIP_FLAG_VIRTUAL = BIT(3),
TPM_CHIP_FLAG_HAVE_TIMEOUTS = BIT(4),
TPM_CHIP_FLAG_ALWAYS_POWERED = BIT(5),
+ TPM_CHIP_FLAG_DO_NOT_CLEAR_OPS = BIT(6),
};
struct tpm_bios_log {
diff --git a/drivers/char/tpm/tpm_tis.c b/drivers/char/tpm/tpm_tis.c
index d29add49b033..a146ef4e499b 100644
--- a/drivers/char/tpm/tpm_tis.c
+++ b/drivers/char/tpm/tpm_tis.c
@@ -273,11 +273,9 @@ static void tpm_tis_pnp_remove(struct pnp_dev *dev)
struct tpm_chip *chip = pnp_get_drvdata(dev);
struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
+ chip->flags |= TPM_CHIP_FLAG_DO_NOT_CLEAR_OPS;
tpm_chip_unregister(chip);
tpm_tis_remove(chip);
- if (is_bsw())
- iounmap(priv->ilb_base_addr);
-
}
static struct pnp_driver tis_pnp_driver = {
@@ -326,12 +324,10 @@ static int tpm_tis_plat_remove(struct platform_device *pdev)
struct tpm_chip *chip = dev_get_drvdata(&pdev->dev);
struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
+ chip->flags |= TPM_CHIP_FLAG_DO_NOT_CLEAR_OPS;
tpm_chip_unregister(chip);
tpm_tis_remove(chip);
- if (is_bsw())
- iounmap(priv->ilb_base_addr);
-
return 0;
}
diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index c2227983ed88..d9099281fc2e 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -727,6 +727,14 @@ void tpm_tis_remove(struct tpm_chip *chip)
if (chip->ops->clk_enable != NULL)
chip->ops->clk_enable(chip, false);
+
+ if (chip->flags & TPM_CHIP_FLAG_DO_NOT_CLEAR_OPS) {
+ down_write(&chip->ops_sem);
+ chip->ops = NULL;
+ up_write(&chip->ops_sem);
+ }
+ if (priv->ilb_base_addr)
+ iounmap(priv->ilb_base_addr);
}
EXPORT_SYMBOL_GPL(tpm_tis_remove);
@@ -922,21 +930,20 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,
}
rc = tpm_chip_register(chip);
- if (rc && is_bsw())
- iounmap(priv->ilb_base_addr);
+ if (rc)
+ goto out_err;
if (chip->ops->clk_enable != NULL)
chip->ops->clk_enable(chip, false);
- return rc;
-out_err:
- tpm_tis_remove(chip);
- if (is_bsw())
- iounmap(priv->ilb_base_addr);
+ return 0;
- if (chip->ops->clk_enable != NULL)
+out_err:
+ if ((chip->ops != NULL) && (chip->ops->clk_enable != NULL))
chip->ops->clk_enable(chip, false);
+ tpm_tis_remove(chip);
+
return rc;
}
EXPORT_SYMBOL_GPL(tpm_tis_core_init);
diff --git a/drivers/char/tpm/tpm_tis_spi.c b/drivers/char/tpm/tpm_tis_spi.c
index 424ff2fde1f2..79c18cfc6519 100644
--- a/drivers/char/tpm/tpm_tis_spi.c
+++ b/drivers/char/tpm/tpm_tis_spi.c
@@ -221,6 +221,7 @@ static int tpm_tis_spi_remove(struct spi_device *dev)
{
struct tpm_chip *chip = spi_get_drvdata(dev);
+ chip->flags |= TPM_CHIP_FLAG_DO_NOT_CLEAR_OPS;
tpm_chip_unregister(chip);
tpm_tis_remove(chip);
return 0;
--
1.9.1
On Thu, Dec 21, 2017 at 12:17:02PM -0800, Azhar Shaikh wrote:
> Commit 3c1701339284353c41 ("tpm: Keep CLKRUN enabled throughout
> the duration of transmit_cmd()") added code which accessed
> chip->ops, even after it was set to NULL in tpm_del_char_device(),
> called from tpm_chip_unregister() in error / driver exit paths.
> So fix this code.
>
> Fixes: 3c1701339284353c41 ("tpm: Keep CLKRUN enabled throughout
> the duration of transmit_cmd()")
>
> Suggested-by: Javier Martinez Canillas <[email protected]>
> Suggested-by: Jason Gunthorpe <[email protected]>
> Signed-off-by: Azhar Shaikh <[email protected]>
> drivers/char/tpm/tpm-chip.c | 5 +++++
> drivers/char/tpm/tpm.h | 1 +
> drivers/char/tpm/tpm_tis.c | 8 ++------
> drivers/char/tpm/tpm_tis_core.c | 23 +++++++++++++++--------
> drivers/char/tpm/tpm_tis_spi.c | 1 +
> 5 files changed, 24 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
> index 0a62c19937b6..c88ec9a32a7e 100644
> +++ b/drivers/char/tpm/tpm-chip.c
> @@ -346,6 +346,10 @@ static void tpm_del_char_device(struct tpm_chip *chip)
> down_write(&chip->ops_sem);
> if (chip->flags & TPM_CHIP_FLAG_TPM2)
> tpm2_shutdown(chip, TPM2_SU_CLEAR);
> + if (chip->flags & TPM_CHIP_FLAG_DO_NOT_CLEAR_OPS) {
> + up_write(&chip->ops_sem);
> + return;
> + }
Yikes, too ugly. Figure something else out.. ops->clk_enable is always
tpm_tis_clkrun_enable at this point, so maybe call it directly in
the removal path in tpm_tis_core?
Jason
>-----Original Message-----
>From: Jason Gunthorpe [mailto:[email protected]]
>Sent: Thursday, December 21, 2017 12:27 PM
>To: Shaikh, Azhar <[email protected]>
>Cc: [email protected]; [email protected];
>[email protected]; [email protected]; linux-
>[email protected]; [email protected]; tpmdd-
>[email protected]
>Subject: Re: [PATCH] tpm: Fix the driver cleanup code
>
>On Thu, Dec 21, 2017 at 12:17:02PM -0800, Azhar Shaikh wrote:
>> Commit 3c1701339284353c41 ("tpm: Keep CLKRUN enabled throughout the
>> duration of transmit_cmd()") added code which accessed
>> chip->ops, even after it was set to NULL in tpm_del_char_device(),
>> called from tpm_chip_unregister() in error / driver exit paths.
>> So fix this code.
>>
>> Fixes: 3c1701339284353c41 ("tpm: Keep CLKRUN enabled throughout the
>> duration of transmit_cmd()")
>>
>> Suggested-by: Javier Martinez Canillas <[email protected]>
>> Suggested-by: Jason Gunthorpe <[email protected]>
>> Signed-off-by: Azhar Shaikh <[email protected]>
>> drivers/char/tpm/tpm-chip.c | 5 +++++
>> drivers/char/tpm/tpm.h | 1 +
>> drivers/char/tpm/tpm_tis.c | 8 ++------
>> drivers/char/tpm/tpm_tis_core.c | 23 +++++++++++++++--------
>> drivers/char/tpm/tpm_tis_spi.c | 1 +
>> 5 files changed, 24 insertions(+), 14 deletions(-)
>>
>> diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
>> index 0a62c19937b6..c88ec9a32a7e 100644
>> +++ b/drivers/char/tpm/tpm-chip.c
>> @@ -346,6 +346,10 @@ static void tpm_del_char_device(struct tpm_chip
>*chip)
>> down_write(&chip->ops_sem);
>> if (chip->flags & TPM_CHIP_FLAG_TPM2)
>> tpm2_shutdown(chip, TPM2_SU_CLEAR);
>> + if (chip->flags & TPM_CHIP_FLAG_DO_NOT_CLEAR_OPS) {
>> + up_write(&chip->ops_sem);
>> + return;
>> + }
>
>Yikes, too ugly. Figure something else out.. ops->clk_enable is always
>tpm_tis_clkrun_enable at this point, so maybe call it directly in the removal
>path in tpm_tis_core?
>
Yes I thought about it too. But if some other chip->ops function in future, which *might* be in this same case, hence for that introduced this flag.
I can use ops->clk_enable instead of introducing the new flag.
>Jason
Regards,
Azhar Shaikh
On Thu, Dec 21, 2017 at 08:31:14PM +0000, Shaikh, Azhar wrote:
> Yes I thought about it too. But if some other chip->ops function in
> future, which *might* be in this same case, hence for that
> introduced this flag.
It can't be - the ops struct is constant, can't be modified, and
tpm_tis_core controls what is set. If someone future person meddles in
this then they can fix here to.
Recommend a short comment in the ops clk_enale initializer and call direct?
Jason
>-----Original Message-----
>From: [email protected] [mailto:linux-integrity-
>[email protected]] On Behalf Of Jason Gunthorpe
>Sent: Thursday, December 21, 2017 12:39 PM
>To: Shaikh, Azhar <[email protected]>
>Cc: [email protected]; [email protected];
>[email protected]; [email protected]; linux-
>[email protected]; [email protected]; tpmdd-
>[email protected]
>Subject: Re: [PATCH] tpm: Fix the driver cleanup code
>
>On Thu, Dec 21, 2017 at 08:31:14PM +0000, Shaikh, Azhar wrote:
>
>> Yes I thought about it too. But if some other chip->ops function in
>> future, which *might* be in this same case, hence for that introduced
>> this flag.
>
>It can't be - the ops struct is constant, can't be modified, and tpm_tis_core
>controls what is set. If someone future person meddles in this then they can
>fix here to.
>
Yes, I checked this part. What I was referring to is any other callback function similar to clk_enable if gets added in future and then needs to
Access ops even after it is set to NULL...
>Recommend a short comment in the ops clk_enale initializer and call direct?
>
But yes I get your point now.
So do you mean something like this?
diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index d9099281fc2e..1187e72483f2 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -716,8 +716,7 @@ void tpm_tis_remove(struct tpm_chip *chip)
u32 interrupt;
int rc;
- if (chip->ops->clk_enable != NULL)
- chip->ops->clk_enable(chip, true);
+ tpm_tis_clkrun_enable(chip, true);
rc = tpm_tis_read32(priv, reg, &interrupt);
if (rc < 0)
@@ -725,14 +724,8 @@ void tpm_tis_remove(struct tpm_chip *chip)
tpm_tis_write32(priv, reg, ~TPM_GLOBAL_INT_ENABLE & interrupt);
- if (chip->ops->clk_enable != NULL)
- chip->ops->clk_enable(chip, false);
+ tpm_tis_clkrun_enable(chip, false);
- if (chip->flags & TPM_CHIP_FLAG_DO_NOT_CLEAR_OPS) {
- down_write(&chip->ops_sem);
- chip->ops = NULL;
- up_write(&chip->ops_sem);
- }
if (priv->ilb_base_addr)
iounmap(priv->ilb_base_addr);
}
>Jason
Regards,
Azhar Shaikh
On Thu, Dec 21, 2017 at 09:54:26PM +0000, Shaikh, Azhar wrote:
> Yes, I checked this part. What I was referring to is any other
> callback function similar to clk_enable if gets added in future and
> then needs to Access ops even after it is set to NULL...
You can't call callback functions after tpm_unregister_chip, it isn't
allowed.
This is a special case where we know the specific implementation of
this specific callback is OK.
> But yes I get your point now.
>
> So do you mean something like this?
Yes
Jason