Re: [PATCH] soundwire: stream: fix an invalid free

[Vinod Koul]

On 07-09-20, 07:25, Tom Rix wrote:
> 
> On 9/7/20 7:14 AM, Vinod Koul wrote:
> > Hello Tom,
> >
> > On 05-09-20, 12:26, trix@xxxxxxxxxx wrote:
> >> From: Tom Rix <trix@xxxxxxxxxx>
> >>
> >> clang static analyzer reports this problem
> >>
> >> stream.c:872:2: warning: Argument to kfree() is a constant
> >>   address (18446744073709551092), which is not memory
> >>   allocated by malloc()
> >>         kfree(stream);
> >>         ^~~~~~~~~~~~~
> >>
> >> In sdw_shutdown_stream() the stream to free is set by
> >> a call to snd_soc_dai_get_sdw_stream().  The problem block
> >> is the check if the call was successful.
> >>
> >> 	if (!sdw_stream) {
> >> 		dev_err(rtd->dev, "no stream found...
> >> 		return;
> >> 	}
> >>
> >> When snd_soc_dai_get_sdw_stream() fails, it does not
> >> always return null, sometimes it returns -ENOTSUPP.
> >>
> >> So also check for error codes.
> >> Fixes: 4550569bd779 ("soundwire: stream: add helper to startup/shutdown streams")
> >> Signed-off-by: Tom Rix <trix@xxxxxxxxxx>
> >> ---
> >>  drivers/soundwire/stream.c | 2 +-
> >>  1 file changed, 1 insertion(+), 1 deletion(-)
> >>
> >> diff --git a/drivers/soundwire/stream.c b/drivers/soundwire/stream.c
> >> index 6e36deb505b1..950231d593c2 100644
> >> --- a/drivers/soundwire/stream.c
> >> +++ b/drivers/soundwire/stream.c
> >> @@ -1913,7 +1913,7 @@ void sdw_shutdown_stream(void *sdw_substream)
> >>  
> >>  	sdw_stream = snd_soc_dai_get_sdw_stream(dai, substream->stream);
> >>  
> >> -	if (!sdw_stream) {
> >> +	if (IS_ERR_OR_NULL(sdw_stream)) {
> > Thanks for the patch. Please see commit 3471d2a192ba ("soundwire:
> > stream: fix NULL/IS_ERR confusion") in soundwire-next. This has already
> > been updated to IS_ERR() and Bard has already sent patches for
> > snd_soc_dai_get_sdw_stream() to return proper values.
> >
> > So I you can rerun this on next, you should see this fixed.
> 
> I am working on linux-next, so I will see Bard's patch when it lands there.

It should be already there... And I checked, looks like there was no
linux-next for last few days and it should be back tomorrow so should be
there

> 
> Sorry for not working on soundwire-next, but since i am fixing everywhere linux-next is easiest. 

Agree, timing this time around!

-- 
~Vinod