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

[Pierre-Louis Bossart]

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

> 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(-)