[patch] w1: small type cleanup in sysfs

[patch] w1: small type cleanup in sysfs

[Dan Carpenter]

On 64 bit systems, a large value for "tmp" could be truncated so we
still end up with a ->max_slave_count which is less than one despite the
"tmp < 1" check.

This is more of a problem for static checkers than a real life issue,
but it's simple enough to fix.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

diff --git a/drivers/w1/w1.c b/drivers/w1/w1.c
index 9eb816b2ea5e..b96f61b15dc6 100644
--- a/drivers/w1/w1.c
+++ b/drivers/w1/w1.c
@@ -320,10 +320,10 @@ static ssize_t w1_master_attribute_show_timeout(struct device *dev, struct devic
 static ssize_t w1_master_attribute_store_max_slave_count(struct device *dev,
 	struct device_attribute *attr, const char *buf, size_t count)
 {
-	long tmp;
+	int tmp;
 	struct w1_master *md = dev_to_w1_master(dev);
 
-	if (kstrtol(buf, 0, &tmp) = -EINVAL || tmp < 1)
+	if (kstrtoint(buf, 0, &tmp) = -EINVAL || tmp < 1)
 		return -EINVAL;
 
 	mutex_lock(&md->mutex);

Re: [patch] w1: small type cleanup in sysfs

[David Fries]

Dan,

I have some other changes in work, how automated is your checkers?
How much work is it for me to give a github repository and branch and
find out if I introduced any problems before submitting them?


I didn't get how you could get a less than one after a check for less
than one from the description or patch until I looked at the rest of
the source code.  Looks good if the description mentions
max_slave_count is an int.

How about wording it,

On 64 bit systems, a large value for "long tmp" is truncated when
assigning to "int md->max_slave_count" so we still end up with a value
less than one despite the "tmp < 1" check.

Acked-by: David Fries <david@fries.net>

On Tue, Feb 11, 2014 at 07:08:26PM +0300, Dan Carpenter wrote:
> On 64 bit systems, a large value for "tmp" could be truncated so we
> still end up with a ->max_slave_count which is less than one despite the
> "tmp < 1" check.
> 
> This is more of a problem for static checkers than a real life issue,
> but it's simple enough to fix.
> 
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> 
> diff --git a/drivers/w1/w1.c b/drivers/w1/w1.c
> index 9eb816b2ea5e..b96f61b15dc6 100644
> --- a/drivers/w1/w1.c
> +++ b/drivers/w1/w1.c
> @@ -320,10 +320,10 @@ static ssize_t w1_master_attribute_show_timeout(struct device *dev, struct devic
>  static ssize_t w1_master_attribute_store_max_slave_count(struct device *dev,
>  	struct device_attribute *attr, const char *buf, size_t count)
>  {
> -	long tmp;
> +	int tmp;
>  	struct w1_master *md = dev_to_w1_master(dev);
>  
> -	if (kstrtol(buf, 0, &tmp) = -EINVAL || tmp < 1)
> +	if (kstrtoint(buf, 0, &tmp) = -EINVAL || tmp < 1)
>  		return -EINVAL;
>  
>  	mutex_lock(&md->mutex);

-- 
David Fries <david@fries.net>    PGP pub CB1EE8F0
http://fries.net/~david/

[patch v2] w1: small type cleanup in sysfs

[Dan Carpenter]

On 64 bit systems, a large value for "long tmp" is truncated when
assigning to "int md->max_slave_count" so we still end up with a value
less than one despite the "tmp < 1" check.

This is more of a problem for static checkers than a real life issue,
but it's simple enough to fix.

Acked-by: David Fries <david@fries.net>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
v2: clarified the commit message

diff --git a/drivers/w1/w1.c b/drivers/w1/w1.c
index 9eb816b2ea5e..b96f61b15dc6 100644
--- a/drivers/w1/w1.c
+++ b/drivers/w1/w1.c
@@ -320,10 +320,10 @@ static ssize_t w1_master_attribute_show_timeout(struct device *dev, struct devic
 static ssize_t w1_master_attribute_store_max_slave_count(struct device *dev,
 	struct device_attribute *attr, const char *buf, size_t count)
 {
-	long tmp;
+	int tmp;
 	struct w1_master *md = dev_to_w1_master(dev);
 
-	if (kstrtol(buf, 0, &tmp) = -EINVAL || tmp < 1)
+	if (kstrtoint(buf, 0, &tmp) = -EINVAL || tmp < 1)
 		return -EINVAL;
 
 	mutex_lock(&md->mutex);

Re: [patch] w1: small type cleanup in sysfs

[Dan Carpenter]

On Tue, Feb 11, 2014 at 10:45:13AM -0600, David Fries wrote:
> Dan,
> 
> I have some other changes in work, how automated is your checkers?
> How much work is it for me to give a github repository and branch and
> find out if I introduced any problems before submitting them?
> 

This is a Smatch thing I'm working on but haven't pushed yet.
Eventually it will be a part of Fengguang Wu's automated kbuild zero
day testing process.

> 
> I didn't get how you could get a less than one after a check for less
> than one from the description or patch until I looked at the rest of
> the source code.  Looks good if the description mentions
> max_slave_count is an int.
> 
> How about wording it,
> 
> On 64 bit systems, a large value for "long tmp" is truncated when
> assigning to "int md->max_slave_count" so we still end up with a value
> less than one despite the "tmp < 1" check.
> 

Sure.  That's clearer.  I have resent it.

regards,
dan carpenter

Re: [patch v2] w1: small type cleanup in sysfs

[Evgeniy Polyakov]

Hi

12.02.2014, 01:08, "Dan Carpenter" <dan.carpenter@oracle.com>:
> On 64 bit systems, a large value for "long tmp" is truncated when
> assigning to "int md->max_slave_count" so we still end up with a value
> less than one despite the "tmp < 1" check.
>
> This is more of a problem for static checkers than a real life issue,
> but it's simple enough to fix.
>
> Acked-by: David Fries <david@fries.net>
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

Looks good to me, thank you
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>