Re: [alsa-devel] SEGFault when optininal snd_ctl_ext_callback::read_event() not set

On Thu, 05 Oct 2017 14:03:14 +0200, Wischer, Timo (ADITG/ESB) wrote:

Hi all,

snd_ctl_ext_callback::read_event() callback is mentioned as optional (see http://git.alsa-project.org/?p=alsa-lib.git;a=blob;f=include/control_externa...)

but there is no NULL check and the NULL pointer will be called if the read_event function callback pointer is not set. (see http://git.alsa-project.org/?p=alsa-lib.git;a=blob;f=src/control/control_ext...)

I think a default function has to be provided which will be called when the callback is not set or the read_event() callback should not be marked as optional.

What is your opinion?

It should have a NULL check there, as documentation clearly states that it's optional.

Care to submit a fix patch?

thanks,

Takashi