[alsa-devel] Applied "ASoC: core: Fix access to uninitialized list heads" to the asoc tree

[Mark Brown]

The patch

   ASoC: core: Fix access to uninitialized list heads

has been applied to the asoc tree at

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git 

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.  

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark

>From 07d22a9bb623714dc3199099c5cce3df6aef496c Mon Sep 17 00:00:00 2001
From: Takashi Iwai <tiwai at suse.de>
Date: Wed, 4 Dec 2019 16:14:54 +0100
Subject: [PATCH] ASoC: core: Fix access to uninitialized list heads

The error path of soc_new_pcm_runtime() invokes soc_free_pcm_runtime()
that may cause a few problems.  First off, it calls list_del() for
rtd->list that may not be initialized.  Similarly,
snd_soc_pcm_component_free() traverses over the component list that
may not be initialized, either.  Such access to the uninitialized list
head would lead to either a BUG_ON() or a memory corruption.

This patch fixes the access to uninitialized list heads by
initializing the list heads properly at the beginning before those
error paths.

Signed-off-by: Takashi Iwai <tiwai at suse.de>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart at linux.intel.com>
Link: https://lore.kernel.org/r/20191204151454.21643-1-tiwai@suse.de
Signed-off-by: Mark Brown <broonie at kernel.org>
---
 sound/soc/soc-core.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c
index 6050c4c62fe8..8ef0efeed0a7 100644
--- a/sound/soc/soc-core.c
+++ b/sound/soc/soc-core.c
@@ -479,6 +479,12 @@ static struct snd_soc_pcm_runtime *soc_new_pcm_runtime(
 		goto free_rtd;
 
 	rtd->dev = dev;
+	INIT_LIST_HEAD(&rtd->list);
+	INIT_LIST_HEAD(&rtd->component_list);
+	INIT_LIST_HEAD(&rtd->dpcm[SNDRV_PCM_STREAM_PLAYBACK].be_clients);
+	INIT_LIST_HEAD(&rtd->dpcm[SNDRV_PCM_STREAM_CAPTURE].be_clients);
+	INIT_LIST_HEAD(&rtd->dpcm[SNDRV_PCM_STREAM_PLAYBACK].fe_clients);
+	INIT_LIST_HEAD(&rtd->dpcm[SNDRV_PCM_STREAM_CAPTURE].fe_clients);
 	dev_set_drvdata(dev, rtd);
 	INIT_DELAYED_WORK(&rtd->delayed_work, close_delayed_work);
 
@@ -494,12 +500,6 @@ static struct snd_soc_pcm_runtime *soc_new_pcm_runtime(
 	/*
 	 * rtd remaining settings
 	 */
-	INIT_LIST_HEAD(&rtd->component_list);
-	INIT_LIST_HEAD(&rtd->dpcm[SNDRV_PCM_STREAM_PLAYBACK].be_clients);
-	INIT_LIST_HEAD(&rtd->dpcm[SNDRV_PCM_STREAM_CAPTURE].be_clients);
-	INIT_LIST_HEAD(&rtd->dpcm[SNDRV_PCM_STREAM_PLAYBACK].fe_clients);
-	INIT_LIST_HEAD(&rtd->dpcm[SNDRV_PCM_STREAM_CAPTURE].fe_clients);
-
 	rtd->card = card;
 	rtd->dai_link = dai_link;
 	if (!rtd->dai_link->ops)
-- 
2.20.1