From mboxrd@z Thu Jan  1 00:00:00 1970
From: Takashi Iwai <tiwai@suse.de>
Subject: Re: Seg. fault when using Salsa 0.0.25
Date: Thu, 05 Nov 2009 12:02:25 +0100
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To: Mogens Lindholdt Lauridsen <MLN@bang-olufsen.dk>
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At Thu, 5 Nov 2009 11:32:39 +0100,
Mogens Lindholdt Lauridsen wrote:
> 
> Hi,
> 
> I got an application which uses Salsa 0.0.25. When I quit this 
> application, it ends with a seg. fault.
> 
> I don't know if this is caused by my application using Salsa wrongly, or a 
> problem in Salsa.
> 
> However, I got a fix for it.
> 
> When my application closes, "hctl_elem_event_handler" is called. And since 
> "helem->private_data" is null, this causes a seg. fault:
>         snd_mixer_elem_t *elem = helem->private_data;
>         snd_mixer_t *mixer = elem->mixer;
> 
> It seems like:
>         if (!elem)
>                 return 0;
> should have been before:
>         snd_mixer_t *mixer = elem->mixer;

Ah, a typical NULL dereference.
Fixed and released as version 0.0.26 now.


thanks,

Takashi