From 2697e4fb9209dfe1d1b24c92d254158f63d4bc8e Mon Sep 17 00:00:00 2001 From: Jarkko Nikula Date: Tue, 15 Apr 2014 16:58:09 +0300 Subject: [PATCH] ASoC: dapm: Fix widget double free with auto-disable DAPM kcontrol Commit 9e1fda4ae158 ("ASoC: dapm: Implement mixer input auto-disable") is trying to free the widget it allocated by snd_soc_dapm_new_control() call in dapm_kcontrol_data_alloc() by adding kfree(data->widget) to dapm_kcontrol_free(). This is causing a widget double free with auto-disabled DAPM kcontrols in sound card unregistration because widgets are already freed before dapm_kcontrol_free() is called. Reason for that is all widgets are added into dapm->card->widgets list in snd_soc_dapm_new_control() and freed in dapm_free_widgets() during execution of snd_soc_dapm_free(). Now snd_soc_dapm_free() calls for different DAPM contexts happens before snd_card_free() call from where the call chain to dapm_kcontrol_free() begins: soc_cleanup_card_resources() soc_remove_dai_links() soc_remove_link_dais() snd_soc_dapm_free(&cpu_dai->dapm) soc_remove_link_components() soc_remove_platform() snd_soc_dapm_free(&platform->dapm) soc_remove_codec() snd_soc_dapm_free(&codec->dapm) snd_soc_dapm_free(&card->dapm) snd_card_free() snd_card_do_free() snd_device_free_all() snd_device_free() snd_ctl_dev_free() snd_ctl_remove() snd_ctl_free_one() dapm_kcontrol_free() This wasn't making harm with ordinary DAPM kcontrols since data->widget is NULL for them. Fixes: 9e1fda4ae158 (ASoC: dapm: Implement mixer input auto-disable) Signed-off-by: Jarkko Nikula Acked-by: Lars-Peter Clausen Signed-off-by: Mark Brown Cc: stable@vger.kernel.org --- sound/soc/soc-dapm.c | 1 - 1 file changed, 1 deletion(-) diff --git a/sound/soc/soc-dapm.c b/sound/soc/soc-dapm.c index c8a780d0d057..7769b0a2bc5a 100644 --- a/sound/soc/soc-dapm.c +++ b/sound/soc/soc-dapm.c @@ -254,7 +254,6 @@ static int dapm_kcontrol_data_alloc(struct snd_soc_dapm_widget *widget, static void dapm_kcontrol_free(struct snd_kcontrol *kctl) { struct dapm_kcontrol_data *data = snd_kcontrol_chip(kctl); - kfree(data->widget); kfree(data->wlist); kfree(data); } -- 2.20.1