Re: [PATCH v3 0/3] ASoC: soundwire: fix port_ready[] dynamic allocation

[Bard liao]

On 8/31/2020 11:12 PM, Pierre-Louis Bossart wrote:
> On 8/30/20 8:27 AM, Bard Liao wrote:
> > The existing code allocates memory for the total number of ports.
> > This only works if the ports are contiguous, but will break if e.g. a
> > Devices uses port0, 1, and 14. The port_ready[] array would contain 3
> > elements, which would lead to an out-of-bounds access. Conversely in
> > other cases, the wrong port index would be used leading to timeouts on
> > prepare.
> >
> > This can be fixed by allocating for the worst-case of 15
> > ports (DP0..DP14). In addition since the number is now fixed, we can
> > use an array instead of a dynamic allocation.
>
> Bard, the order of patches will break git bisect, no? I tried on my 
> side and get the following error after applying patch1
>
> sound/soc/codecs/max98373-sdw.c:337:20: error: assignment to 
> expression with array type
>   337 |  slave->port_ready = devm_kcalloc(&slave->dev, num_of_ports,
>       |
>
> the order should be
>
> ASoC: codecs: soundwire: remove port_ready[] usage from codecs.
> soundwire: add definition for maximum number of ports
> soundwire: fix port_ready[] dynamic allocation in mipi_disco


Thanks Pierre. I will send a new version soon.


> > Changes in v3:
> > - Add ASoC tag in the cover letter title.
> > - Edit the title and commit message of the third patch for better
> >    understanding.
> >
> > Changes in v2:
> > - Split patches into sdw and asoc patches. Please note that "soundwire:
> >    fix port_ready[] dynamic allocation in mipi_disco" and "ASoC: codecs:
> >    fix port_ready[] dynamic allocation in ASoC codecs" should be merged
> >    at the same time.
> >
> > Pierre-Louis Bossart (3):
> >    soundwire: add definition for maximum number of ports
> >    soundwire: fix port_ready[] dynamic allocation in mipi_disco
> >    ASoC: codecs: soundwire: remove port_ready[] usage from codecs.
> >
> >   drivers/soundwire/mipi_disco.c  | 18 +-----------------
> >   drivers/soundwire/slave.c       |  4 ++++
> >   include/linux/soundwire/sdw.h   |  5 +++--
> >   sound/soc/codecs/max98373-sdw.c | 15 +--------------
> >   sound/soc/codecs/rt1308-sdw.c   | 14 +-------------
> >   sound/soc/codecs/rt5682-sdw.c   | 15 +--------------
> >   sound/soc/codecs/rt700-sdw.c    | 15 +--------------
> >   sound/soc/codecs/rt711-sdw.c    | 15 +--------------
> >   sound/soc/codecs/rt715-sdw.c    | 33 +--------------------------------
> >   9 files changed, 14 insertions(+), 120 deletions(-)