[alsa-devel] [PATCH 07/10] ALSA: rme96: Return error code in PCM copy ops

[Takashi Iwai]

At Fri, 15 Nov 2013 10:40:07 +0100,
Knut Petersen wrote:
> 
> On 29.10.2013 17:00, Takashi Iwai wrote:
> > Just pass the error code returned from copy_from_user_toio() and
> > copy_to_user_fromio() helpers.
> >
> > Spotted by coverity CID 114119.
> >
> > Signed-off-by: Takashi Iwai <tiwai at suse.de>
> > ---
> >   sound/pci/rme96.c | 10 ++++------
> >   1 file changed, 4 insertions(+), 6 deletions(-)
> >
> > diff --git a/sound/pci/rme96.c b/sound/pci/rme96.c
> > index bb9ebc5543d7..0236363c301f 100644
> > --- a/sound/pci/rme96.c
> > +++ b/sound/pci/rme96.c
> > @@ -350,9 +350,8 @@ snd_rme96_playback_copy(struct snd_pcm_substream *substream,
> >   	struct rme96 *rme96 = snd_pcm_substream_chip(substream);
> >   	count <<= rme96->playback_frlog;
> >   	pos <<= rme96->playback_frlog;
> > -	copy_from_user_toio(rme96->iobase + RME96_IO_PLAY_BUFFER + pos, src,
> > -			    count);
> > -	return 0;
> > +	return copy_from_user_toio(rme96->iobase + RME96_IO_PLAY_BUFFER + pos, src,
> > +				   count);
> 
> Under which circumstances could copy_from_user_toio() fail?

When copy_from_user() fails.

> >   }
> >   
> >   static int
> > @@ -365,9 +364,8 @@ snd_rme96_capture_copy(struct snd_pcm_substream *substream,
> >   	struct rme96 *rme96 = snd_pcm_substream_chip(substream);
> >   	count <<= rme96->capture_frlog;
> >   	pos <<= rme96->capture_frlog;
> > -	copy_to_user_fromio(dst, rme96->iobase + RME96_IO_REC_BUFFER + pos,
> > -			    count);
> > -        return 0;
> > +	return copy_to_user_fromio(dst, rme96->iobase + RME96_IO_REC_BUFFER + pos,
> > +				   count);
> When will copy_to_user_fromio() fail?

When copy_to_user() fails.


Takashi