Re: [PATCH] hda: add bounds checking for the codec command fields v2

[Wu Fengguang <fengguang.wu@intel.com>]

On Fri, Jul 17, 2009 at 06:46:01PM +0800, Takashi Iwai wrote:
> At Fri, 17 Jul 2009 18:41:05 +0800,
> Guo, Chaohong wrote:
> > 
> > Although it does address this issue, I am not comfortable with this fixing. 
> > It seems more like a workaround than fix.
> 
> No, it's rather for catching a bug.  This is definitely neither
> "workaround" nor "fix".

Yes, I wrote this mainly for catching unknown bugs.

> >  Moreover, if long format node
> > ID is used in the future,  the code will cause little trouble for maintaining.
> 
> Well, the current code doesn't support the long id (as the restriction
> of HD-audio controller side), so we'd need major changes in anyway.
> Thus this check is no big issue for maintenance, at least to me :)

Does the HDA spec define cmd format that accept long form NID?
If so, can you point me to the specific location please? Thanks.

> > what I want is to fix it during parsing connection list, and verify the node
> > id is valid there .  
> 
> Heh, this was already fixed :)

AFAIK, snd_hda_get_connections() won't return NIDs bigger than
0x7f(short) or 0x7ffff(long).

Thanks,
Fengguang