Hi Takashi,

i think mix is same as ext->data instead ext. ext is of extplug_priv_t *; so it is definitely not mix which is of snd_pcm_upmix_t

33 struct snd_pcm_upmix { 34 snd_pcm_extplug_t ext;

typedef struct snd_pcm_extplug_priv { snd_pcm_plugin_t plug; snd_pcm_extplug_t *data; between upmix and extplug_priv, there is a gap plug, which forbid ext to be converted to mix directly. so free(ext) in snd_pcm_extplug_close does NOT promise it will free mix too.

2017-08-30 15:02 GMT+08:00 Takashi Iwai tiwai@suse.de:

On Wed, 30 Aug 2017 07:51:59 +0200, boozer asm wrote:

...

eg. in function:SND_PCM_PLUGIN_DEFINE_FUNC(upmix) 487 mix = calloc(1, sizeof(*mix)); 488 if (mix == NULL) 489 return -ENOMEM;

mix is allocated here. but at close function, it is not freed, and no __destructor function available to free it.

and in alsa-lib/src/pcm/pcm_extplug.c static int snd_pcm_extplug_close(snd_pcm_t *pcm) { extplug_priv_t *ext = pcm->private_data;

snd_pcm_close(ext->plug.gen.slave);
clear_ext_params(ext);
if (ext->data->callback->close)
{
    ext->data->callback->close(ext->data);
}
free(ext);
return 0;

} this function does NOT free ext->data. and 366 static int upmix_close(snd_pcm_extplug_t *ext) 367 { 368 snd_pcm_upmix_t *mix = (snd_pcm_upmix_t *)ext; 369 free(mix->delayline[0]); 370 free(mix->delayline[1]); 371 return 0; 372 }

and this function does NOT free mix itself.

so I think there is memory leak.

It's freed in snd_pcm_extplug_close(). mix is identical with ext in the case of upmix.

Takashi

not sure what's the best place to call free. 1. static int snd_pcm_extplug_close(snd_pcm_t *pcm) { extplug_priv_t *ext = pcm->private_data;

snd_pcm_close(ext->plug.gen.slave); clear_ext_params(ext); if (ext->data->callback->close) { ext->data->callback->close(ext->data); } if (ext->data) free(ext->data); free(ext); return 0; }

2. 366 static int upmix_close(snd_pcm_extplug_t *ext) 367 { 368 snd_pcm_upmix_t *mix = (snd_pcm_upmix_t *)ext; 369 free(mix->delayline[0]); 370 free(mix->delayline[1]); free(mix); 371 return 0; 372 }

3. apply method in alsa-plugins/maemo/alsa-dsp.c:748:static void alsa_dsp_descructor(void) __attribute__ ((destructor));

with each methods, there are some plugins pcm_ files affected.

2017-08-30 16:17 GMT+08:00 Takashi Iwai tiwai@suse.de:

On Wed, 30 Aug 2017 09:59:59 +0200, boozer asm wrote:

...

Hi Takashi,

i think mix is same as ext->data instead ext. ext is of extplug_priv_t *; so it is definitely not mix which is of snd_pcm_upmix_t

33 struct snd_pcm_upmix { 34 snd_pcm_extplug_t ext;

typedef struct snd_pcm_extplug_priv { snd_pcm_plugin_t plug; snd_pcm_extplug_t *data; between upmix and extplug_priv, there is a gap plug, which forbid ext to

be

...

converted to mix directly. so free(ext) in snd_pcm_extplug_close does NOT promise it will free mix

too.

OK, then care to submit patches?

thanks,

Takashi