[PATCH] TPM: Long default timeout fix

[PATCH] TPM: Long default timeout fix

[Rajiv Andrade]

If duration variable value is 0 at this point, it's because
chip->vendor.duration wasn't filled by tpm_get_timeouts() yet.
This patch sets then the lowest timeout just to give enough
time for tpm_get_timeouts() to further succeed.

This fix avoids long boot times in case another entity attempts
to send commands to the TPM when the TPM isn't accessible.

Signed-off-by: Rajiv Andrade <srajiv@linux.vnet.ibm.com>
---
 drivers/char/tpm/tpm.c |   10 ++++++----
 1 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/char/tpm/tpm.c b/drivers/char/tpm/tpm.c
index 7c41335..5635ac0 100644
--- a/drivers/char/tpm/tpm.c
+++ b/drivers/char/tpm/tpm.c
@@ -364,12 +364,14 @@ unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip,
 		    tpm_protected_ordinal_duration[ordinal &
 						   TPM_PROTECTED_ORDINAL_MASK];
 
-	if (duration_idx != TPM_UNDEFINED)
+	if (duration_idx != TPM_UNDEFINED) {
 		duration = chip->vendor.duration[duration_idx];
-	if (duration <= 0)
+		/* if duration is 0, it's because chip->vendor.duration wasn't */
+		/* filled yet, so we set the lowest timeout just to give enough */
+		/* time for tpm_get_timeouts() to succeed */
+		return (duration <= 0 ? HZ : duration);
+	} else 
 		return 2 * 60 * HZ;
-	else
-		return duration;
 }
 EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
 
-- 
1.7.2.3

Re: [PATCH] TPM: Long default timeout fix

[Michal Schmidt]

James,

what is the status of this patch from Rajiv? It has been in Fedora
kernels for some time, but I do not see it applied upstream:

On Fri, 12 Nov 2010 19:18:50 -0200 Rajiv Andrade wrote:
> If duration variable value is 0 at this point, it's because
> chip->vendor.duration wasn't filled by tpm_get_timeouts() yet.
> This patch sets then the lowest timeout just to give enough
> time for tpm_get_timeouts() to further succeed.
> 
> This fix avoids long boot times in case another entity attempts
> to send commands to the TPM when the TPM isn't accessible.
> 
> Signed-off-by: Rajiv Andrade <srajiv@linux.vnet.ibm.com>
> ---
>  drivers/char/tpm/tpm.c |   10 ++++++----
>  1 files changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/char/tpm/tpm.c b/drivers/char/tpm/tpm.c
> index 7c41335..5635ac0 100644
> --- a/drivers/char/tpm/tpm.c
> +++ b/drivers/char/tpm/tpm.c
> @@ -364,12 +364,14 @@ unsigned long tpm_calc_ordinal_duration(struct
> tpm_chip *chip, tpm_protected_ordinal_duration[ordinal &
>  						   TPM_PROTECTED_ORDINAL_MASK];
>  
> -	if (duration_idx != TPM_UNDEFINED)
> +	if (duration_idx != TPM_UNDEFINED) {
>  		duration = chip->vendor.duration[duration_idx];
> -	if (duration <= 0)
> +		/* if duration is 0, it's because
> chip->vendor.duration wasn't */
> +		/* filled yet, so we set the lowest timeout just to
> give enough */
> +		/* time for tpm_get_timeouts() to succeed */
> +		return (duration <= 0 ? HZ : duration);
> +	} else 
>  		return 2 * 60 * HZ;
> -	else
> -		return duration;
>  }
>  EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
>  

Re: [PATCH] TPM: Long default timeout fix

[James Morris]

On Thu, 20 Jan 2011, Michal Schmidt wrote:

> James,
> 
> what is the status of this patch from Rajiv? It has been in Fedora
> kernels for some time, but I do not see it applied upstream:

I don't know -- was it sent to me?

> 
> On Fri, 12 Nov 2010 19:18:50 -0200 Rajiv Andrade wrote:
> > If duration variable value is 0 at this point, it's because
> > chip->vendor.duration wasn't filled by tpm_get_timeouts() yet.
> > This patch sets then the lowest timeout just to give enough
> > time for tpm_get_timeouts() to further succeed.
> > 
> > This fix avoids long boot times in case another entity attempts
> > to send commands to the TPM when the TPM isn't accessible.
> > 
> > Signed-off-by: Rajiv Andrade <srajiv@linux.vnet.ibm.com>
> > ---
> >  drivers/char/tpm/tpm.c |   10 ++++++----
> >  1 files changed, 6 insertions(+), 4 deletions(-)
> > 
> > diff --git a/drivers/char/tpm/tpm.c b/drivers/char/tpm/tpm.c
> > index 7c41335..5635ac0 100644
> > --- a/drivers/char/tpm/tpm.c
> > +++ b/drivers/char/tpm/tpm.c
> > @@ -364,12 +364,14 @@ unsigned long tpm_calc_ordinal_duration(struct
> > tpm_chip *chip, tpm_protected_ordinal_duration[ordinal &
> >  						   TPM_PROTECTED_ORDINAL_MASK];
> >  
> > -	if (duration_idx != TPM_UNDEFINED)
> > +	if (duration_idx != TPM_UNDEFINED) {
> >  		duration = chip->vendor.duration[duration_idx];
> > -	if (duration <= 0)
> > +		/* if duration is 0, it's because
> > chip->vendor.duration wasn't */
> > +		/* filled yet, so we set the lowest timeout just to
> > give enough */
> > +		/* time for tpm_get_timeouts() to succeed */
> > +		return (duration <= 0 ? HZ : duration);
> > +	} else 
> >  		return 2 * 60 * HZ;
> > -	else
> > -		return duration;
> >  }
> >  EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
> >  
> 

-- 
James Morris
<jmorris@namei.org>

Re: [PATCH] TPM: Long default timeout fix

[James Morris]

On Thu, 20 Jan 2011, Michal Schmidt wrote:

> what is the status of this patch from Rajiv? It has been in Fedora
> kernels for some time, but I do not see it applied upstream:
> 
> On Fri, 12 Nov 2010 19:18:50 -0200 Rajiv Andrade wrote:
> > If duration variable value is 0 at this point, it's because
> > chip->vendor.duration wasn't filled by tpm_get_timeouts() yet.
> > This patch sets then the lowest timeout just to give enough
> > time for tpm_get_timeouts() to further succeed.
> > 
> > This fix avoids long boot times in case another entity attempts
> > to send commands to the TPM when the TPM isn't accessible.
> > 
> > Signed-off-by: Rajiv Andrade <srajiv@linux.vnet.ibm.com>

Applied to
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6#for-linus

-- 
James Morris
<jmorris@namei.org>