Adding Greg... On Tue, Aug 12, 2014 at 9:30 PM, Stepan Moskovchenko <stepanm@xxxxxxxxxxxxxx> wrote: > When we parse the device tree and allocate platform > devices, the 'name' of the newly-created platform_device > is set to point to the 'name' field of the 'struct device' > embedded within the platform_device. This is dangerous, > because the name of the 'struct device' is dynamically > allocated. Drivers may call dev_set_name() on the device, > which will free and reallocate the name of the device, > leaving the 'name' of the platform_device pointing to the > now-freed memory. > > Furthermore, if the dev_set_name() call is made from a > driver's probe() function and a subsequent request results > in probe deferral, the dangling 'name' reference may lead > to the device being re-probed using the wrong driver. This seems wrong. I don't think we want drivers to change their own device's name. The name is not supposed to change after registration. Rob > To mitigate these scenarios, we use kstrdup to perform a > deep copy of the device name when assigning the name of the > platform_device, so that the platform_device name is > unaffected by any calls to dev_set_name() that might made > by drivers to rename the embedded 'struct device'. > > Signed-off-by: Stepan Moskovchenko <stepanm@xxxxxxxxxxxxxx> > --- > * v2 - swap cleanup order > > drivers/of/device.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/of/device.c b/drivers/of/device.c > index f685e55..e9beae6 100644 > --- a/drivers/of/device.c > +++ b/drivers/of/device.c > @@ -54,7 +54,7 @@ int of_device_add(struct platform_device *ofdev) > > /* name and id have to be set so that the platform bus doesn't get > * confused on matching */ > - ofdev->name = dev_name(&ofdev->dev); > + ofdev->name = kstrdup(dev_name(&ofdev->dev), GFP_KERNEL); > ofdev->id = -1; > > /* device_add will assume that this device is on the same node as > @@ -75,6 +75,7 @@ EXPORT_SYMBOL(of_device_register); > > void of_device_unregister(struct platform_device *ofdev) > { > + kfree(ofdev->name); > device_unregister(&ofdev->dev); > } > EXPORT_SYMBOL(of_device_unregister); > -- > The Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, > hosted by The Linux Foundation > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html