Commit fe581391 authored Aug 01, 2013 by Lars-Peter Clausen Committed by Mark Brown Aug 01, 2013

ASoC: dapm: Fix empty list check in dapm_new_mux()



list_first_entry() will always return a valid pointer, even if the list is
empty. So the check whether path is NULL will always be false. So we end up
calling dapm_create_or_share_mixmux_kcontrol() with a path struct that points
right in the middle of the widget struct and by trying to modify the path the
widgets memory will become corrupted. Fix this by using list_emtpy() to check if
the widget doesn't have any paths.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Tested-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Cc: stable@vger.kernel.org

parent 56a67834

sound/soc/soc-dapm.c

+4 −3

Original line number	Diff line number	Diff line
		@@ -679,13 +679,14 @@ static int dapm_new_mux(struct snd_soc_dapm_widget *w)
		return -EINVAL;
		}

		path = list_first_entry(&w->sources, struct snd_soc_dapm_path,
		list_sink);
		if (!path) {
		if (list_empty(&w->sources)) {
		dev_err(dapm->dev, "ASoC: mux %s has no paths\n", w->name);
		return -EINVAL;
		}

		path = list_first_entry(&w->sources, struct snd_soc_dapm_path,
		list_sink);

		ret = dapm_create_or_share_mixmux_kcontrol(w, 0, path);
		if (ret < 0)
		return ret;