If there is anything in damp->path_source_cache or damp->path_sink_cache, it can not be valid after the widgets have been freed. Without this patch a repeated remove and load of a machine driver may cause NULL pointer reference in dapm_wcache_lookup() when a freed widget, not belonging to any list, is haunting in the wcache.

Signed-off-by: Jyri Sarha jsarha@ti.com Reported-by: Felipe Balbi balbi@ti.com --- The patch fixes the problem reported here: http://mailman.alsa-project.org/pipermail/alsa-devel/2015-October/099431.htm...

sound/soc/soc-dapm.c | 3 +++ 1 file changed, 3 insertions(+)

diff --git a/sound/soc/soc-dapm.c b/sound/soc/soc-dapm.c index ff8bda4..d78db59 100644 --- a/sound/soc/soc-dapm.c +++ b/sound/soc/soc-dapm.c @@ -2286,6 +2286,9 @@ static void dapm_free_widgets(struct snd_soc_dapm_context *dapm) continue; snd_soc_dapm_free_widget(w); } + + dapm->path_sink_cache.widget = NULL; + dapm->path_source_cache.widget = NULL; }

static struct snd_soc_dapm_widget *dapm_find_widget(