On Wed, Nov 09, 2016 at 11:58:31AM +0100, Oliver Neukum wrote: > On Tue, 2016-11-08 at 16:41 +0100, Johan Hovold wrote: > > On Tue, Nov 08, 2016 at 03:13:13PM +0100, Oliver Neukum wrote: > > > On Tue, 2016-11-08 at 13:26 +0100, Johan Hovold wrote: > > > > Drop invalid user-pointer checks from ioctl handlers. > > > > > > > > A NULL-pointer can be valid in user space and copy_to_user() takes > > > > care > > > > of sanity checking. > > > > > > Shouldn't we bail out early in these cases? > > > > I don't think it's worth it, and this is also the general pattern for > > such ioctls. The added overhead for an error case like this is really > > negligible. > > OK, as you say. Also remember that access_ok() is not a sufficient sanity check, and would specifically fail to catch the NULL-pointer case. Thanks, Johan -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
