| Message ID | 20240919075815.332017-1-amitsd@google.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [v1] usb: typec: Fix arg check for usb_power_delivery_unregister_capabilities | expand |
On Thu, Sep 19, 2024 at 12:58:12AM -0700, Amit Sunil Dhamne wrote: > usb_power_delivery_register_capabilities() returns ERR_PTR in case of > failure. usb_power_delivery_unregister_capabilities() we only check > argument ("cap") for NULL. A more robust check would be checking for > ERR_PTR as well. > > Cc: stable@vger.kernel.org > Fixes: 662a60102c12 ("usb: typec: Separate USB Power Delivery from USB Type-C") > Signed-off-by: Amit Sunil Dhamne <amitsd@google.com> > Reviewed-by: Badhri Jagan Sridharan <badhri@google.com> > --- > drivers/usb/typec/pd.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/usb/typec/pd.c b/drivers/usb/typec/pd.c > index d78c04a421bc..761fe4dddf1b 100644 > --- a/drivers/usb/typec/pd.c > +++ b/drivers/usb/typec/pd.c > @@ -519,7 +519,7 @@ EXPORT_SYMBOL_GPL(usb_power_delivery_register_capabilities); > */ > void usb_power_delivery_unregister_capabilities(struct usb_power_delivery_capabilities *cap) > { > - if (!cap) > + if (IS_ERR_OR_NULL(cap)) This feels like there's a wrong caller, why would this be called with an error value in the first place? Why not fix that? And why would this be called with NULL as well in the first place? thanks, greg k-h
On Thu, Sep 19, 2024 at 12:58:12AM GMT, Amit Sunil Dhamne wrote: > usb_power_delivery_register_capabilities() returns ERR_PTR in case of > failure. usb_power_delivery_unregister_capabilities() we only check > argument ("cap") for NULL. A more robust check would be checking for > ERR_PTR as well. No. The calling drivers are not supposed to pass ERR_PTR to usb_power_delivery_unregister_capabilities(). If you check the TCPM and UCSI driver code, they check return value of the register function before saving it internally. > Cc: stable@vger.kernel.org > Fixes: 662a60102c12 ("usb: typec: Separate USB Power Delivery from USB Type-C") > Signed-off-by: Amit Sunil Dhamne <amitsd@google.com> > Reviewed-by: Badhri Jagan Sridharan <badhri@google.com> > --- > drivers/usb/typec/pd.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/usb/typec/pd.c b/drivers/usb/typec/pd.c > index d78c04a421bc..761fe4dddf1b 100644 > --- a/drivers/usb/typec/pd.c > +++ b/drivers/usb/typec/pd.c > @@ -519,7 +519,7 @@ EXPORT_SYMBOL_GPL(usb_power_delivery_register_capabilities); > */ > void usb_power_delivery_unregister_capabilities(struct usb_power_delivery_capabilities *cap) > { > - if (!cap) > + if (IS_ERR_OR_NULL(cap)) > return; > > device_for_each_child(&cap->dev, NULL, remove_pdo); > > base-commit: 68d4209158f43a558c5553ea95ab0c8975eab18c > -- > 2.46.0.792.g87dc391469-goog >
On Thu, Sep 19, 2024 at 10:11:37AM GMT, Greg KH wrote: > On Thu, Sep 19, 2024 at 12:58:12AM -0700, Amit Sunil Dhamne wrote: > > usb_power_delivery_register_capabilities() returns ERR_PTR in case of > > failure. usb_power_delivery_unregister_capabilities() we only check > > argument ("cap") for NULL. A more robust check would be checking for > > ERR_PTR as well. > > > > Cc: stable@vger.kernel.org > > Fixes: 662a60102c12 ("usb: typec: Separate USB Power Delivery from USB Type-C") > > Signed-off-by: Amit Sunil Dhamne <amitsd@google.com> > > Reviewed-by: Badhri Jagan Sridharan <badhri@google.com> > > --- > > drivers/usb/typec/pd.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/drivers/usb/typec/pd.c b/drivers/usb/typec/pd.c > > index d78c04a421bc..761fe4dddf1b 100644 > > --- a/drivers/usb/typec/pd.c > > +++ b/drivers/usb/typec/pd.c > > @@ -519,7 +519,7 @@ EXPORT_SYMBOL_GPL(usb_power_delivery_register_capabilities); > > */ > > void usb_power_delivery_unregister_capabilities(struct usb_power_delivery_capabilities *cap) > > { > > - if (!cap) > > + if (IS_ERR_OR_NULL(cap)) > > This feels like there's a wrong caller, why would this be called with an > error value in the first place? Why not fix that? And why would this > be called with NULL as well in the first place? I think passing NULL matches the rest of the kernel, it removes unnecessary if(!NULL) statements from the caller side.
Hi Greg, Dmitry, Thanks for the review! On 9/19/24 3:03 AM, Dmitry Baryshkov wrote: > On Thu, Sep 19, 2024 at 10:11:37AM GMT, Greg KH wrote: >> On Thu, Sep 19, 2024 at 12:58:12AM -0700, Amit Sunil Dhamne wrote: >>> usb_power_delivery_register_capabilities() returns ERR_PTR in case of >>> failure. usb_power_delivery_unregister_capabilities() we only check >>> argument ("cap") for NULL. A more robust check would be checking for >>> ERR_PTR as well. >>> >>> Cc: stable@vger.kernel.org >>> Fixes: 662a60102c12 ("usb: typec: Separate USB Power Delivery from USB Type-C") >>> Signed-off-by: Amit Sunil Dhamne <amitsd@google.com> >>> Reviewed-by: Badhri Jagan Sridharan <badhri@google.com> >>> --- >>> drivers/usb/typec/pd.c | 2 +- >>> 1 file changed, 1 insertion(+), 1 deletion(-) >>> >>> diff --git a/drivers/usb/typec/pd.c b/drivers/usb/typec/pd.c >>> index d78c04a421bc..761fe4dddf1b 100644 >>> --- a/drivers/usb/typec/pd.c >>> +++ b/drivers/usb/typec/pd.c >>> @@ -519,7 +519,7 @@ EXPORT_SYMBOL_GPL(usb_power_delivery_register_capabilities); >>> */ >>> void usb_power_delivery_unregister_capabilities(struct usb_power_delivery_capabilities *cap) >>> { >>> - if (!cap) >>> + if (IS_ERR_OR_NULL(cap)) >> This feels like there's a wrong caller, why would this be called with an >> error value in the first place? Why not fix that? And why would this >> be called with NULL as well in the first place? > I think passing NULL matches the rest of the kernel, it removes > unnecessary if(!NULL) statements from the caller side. > The reason for this patch was just to be a little more defensive in case things slip through cracks and be consistent with the rest of the PD class. For example usb_power_delivery_unregister() & usb_power_delivery_unlink_device() has similar arg checks. Regards, Amit
diff --git a/drivers/usb/typec/pd.c b/drivers/usb/typec/pd.c index d78c04a421bc..761fe4dddf1b 100644 --- a/drivers/usb/typec/pd.c +++ b/drivers/usb/typec/pd.c @@ -519,7 +519,7 @@ EXPORT_SYMBOL_GPL(usb_power_delivery_register_capabilities); */ void usb_power_delivery_unregister_capabilities(struct usb_power_delivery_capabilities *cap) { - if (!cap) + if (IS_ERR_OR_NULL(cap)) return; device_for_each_child(&cap->dev, NULL, remove_pdo);
usb_power_delivery_register_capabilities() returns ERR_PTR in case of failure. usb_power_delivery_unregister_capabilities() we only check argument ("cap") for NULL. A more robust check would be checking for ERR_PTR as well. Cc: stable@vger.kernel.org Fixes: 662a60102c12 ("usb: typec: Separate USB Power Delivery from USB Type-C") Signed-off-by: Amit Sunil Dhamne <amitsd@google.com> Reviewed-by: Badhri Jagan Sridharan <badhri@google.com> --- drivers/usb/typec/pd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) base-commit: 68d4209158f43a558c5553ea95ab0c8975eab18c