On Mon, Jul 10, 2017 at 10:11:37AM +0300, Dan Carpenter wrote: > The ptp_clock_register() function returns NULL when it's #ifdefed out > because CONFIG_PTP_1588_CLOCK is disabled. Otherwise, it's intended to > return error pointers. Unfortunately, there are a couple paths where we > forget to set the error code. It means that we could result in NULL > pointer dereferences in the callers.
Actually, this description is bogus. Callers will not dereference NULL, because they are required to check the returned pointer: /** * ptp_clock_register() - register a PTP hardware clock driver * * @info: Structure describing the new clock. * @parent: Pointer to the parent device of the new clock. * * Returns a valid pointer on success or PTR_ERR on failure. If PHC * support is missing at the configuration level, this function * returns NULL, and drivers are expected to gracefully handle that * case separately. */ Thanks, Richard
