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

[Wischer, Timo (ADITG/ESB)]

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_external.h;h=12958e70a5230de9c74029c641a395a2073c8646;hb=refs/heads/master#l239)

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.c;h=56552fa1aa0ef0e6383abf4029b63944a841c2c4;hb=refs/heads/master#l419)

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?





Best regards



Timo Wischer

 

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