Re: [PATCH] thermal: Fix potential NULL pointer accesses

[Zhang Rui <rui.zhang@intel.com>]

On 三, 2012-08-08 at 23:25 -0700, Guenter Roeck wrote:
> On Thu, Aug 09, 2012 at 08:44:55AM +0800, Zhang Rui wrote:
> > On 二, 2012-08-07 at 22:36 -0700, Guenter Roeck wrote:
> > > The type parameter in thermal_zone_device_register and
> > > thermal_cooling_device_register can be NULL, indicating that no sysfs attribute
> > > for the type should be created. Only call strlen() and strcpy() on type if it is
> > > not NULL.
> > > 
> > > This patch addresses Coverity #102180 and #102182: Dereference before null check
> > > 
> > > Signed-off-by: Guenter Roeck <linux@roeck-us.net>
> > 
> > Acked-by: Zhang Rui <rui.zhang@intel.com>
> > 
> How do we get this patch upstream ? I thought you'd take it through your tree.
> 
yep.

thanks,
rui
> Thanks,
> Guenter
> 
> > > ---
> > > Applies on top of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux.git (thermal).
> > > 
> > >  drivers/thermal/thermal_sys.c |    8 ++++----
> > >  1 file changed, 4 insertions(+), 4 deletions(-)
> > > 
> > > diff --git a/drivers/thermal/thermal_sys.c b/drivers/thermal/thermal_sys.c
> > > index 5be8728..e69f76d 100644
> > > --- a/drivers/thermal/thermal_sys.c
> > > +++ b/drivers/thermal/thermal_sys.c
> > > @@ -900,7 +900,7 @@ thermal_cooling_device_register(char *type, void *devdata,
> > >  	struct thermal_zone_device *pos;
> > >  	int result;
> > >  
> > > -	if (strlen(type) >= THERMAL_NAME_LENGTH)
> > > +	if (type && strlen(type) >= THERMAL_NAME_LENGTH)
> > >  		return ERR_PTR(-EINVAL);
> > >  
> > >  	if (!ops || !ops->get_max_state || !ops->get_cur_state ||
> > > @@ -917,7 +917,7 @@ thermal_cooling_device_register(char *type, void *devdata,
> > >  		return ERR_PTR(result);
> > >  	}
> > >  
> > > -	strcpy(cdev->type, type);
> > > +	strcpy(cdev->type, type ? : "");
> > >  	mutex_init(&cdev->lock);
> > >  	INIT_LIST_HEAD(&cdev->thermal_instances);
> > >  	cdev->ops = ops;
> > > @@ -1343,7 +1343,7 @@ struct thermal_zone_device *thermal_zone_device_register(const char *type,
> > >  	int count;
> > >  	int passive = 0;
> > >  
> > > -	if (strlen(type) >= THERMAL_NAME_LENGTH)
> > > +	if (type && strlen(type) >= THERMAL_NAME_LENGTH)
> > >  		return ERR_PTR(-EINVAL);
> > >  
> > >  	if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips)
> > > @@ -1365,7 +1365,7 @@ struct thermal_zone_device *thermal_zone_device_register(const char *type,
> > >  		return ERR_PTR(result);
> > >  	}
> > >  
> > > -	strcpy(tz->type, type);
> > > +	strcpy(tz->type, type ? : "");
> > >  	tz->ops = ops;
> > >  	tz->device.class = &thermal_class;
> > >  	tz->devdata = devdata;
> > 
> > 
> >