releases/3.18.6/asoc-soc-compress.c-fix-null-dereference.patch

From d3268a40d4b19ff7bee23f52eabbc4e96bb685e8 Mon Sep 17 00:00:00 2001
From: Qais Yousef <qais.yousef@imgtec.com>
Date: Wed, 14 Jan 2015 08:47:29 +0000
Subject: ASoC: soc-compress.c: fix NULL dereference

From: Qais Yousef <qais.yousef@imgtec.com>

commit d3268a40d4b19ff7bee23f52eabbc4e96bb685e8 upstream.

In soc_new_compress() when rtd->dai_link->dynamic is set, we create the pcm
substreams with this call:

   ret = snd_pcm_new_internal(rtd->card->snd_card, new_name, num,
                                   1, 0, &be_pcm);

which passes 0 as capture_count leading to

   be_pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream

being NULL, hence when trying to set rtd a few lines below we get an oops.

Fix by using rtd->dai_link->dpcm_playback and rtd->dai_link->dpcm_capture as
playback_count and capture_count to snd_pcm_new_internal().

Signed-off-by: Qais Yousef <qais.yousef@imgtec.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 sound/soc/soc-compress.c |    9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

--- a/sound/soc/soc-compress.c
+++ b/sound/soc/soc-compress.c
@@ -666,7 +666,8 @@ int soc_new_compress(struct snd_soc_pcm_
 			rtd->dai_link->stream_name);
 
 		ret = snd_pcm_new_internal(rtd->card->snd_card, new_name, num,
-				1, 0, &be_pcm);
+				rtd->dai_link->dpcm_playback,
+				rtd->dai_link->dpcm_capture, &be_pcm);
 		if (ret < 0) {
 			dev_err(rtd->card->dev, "ASoC: can't create compressed for %s\n",
 				rtd->dai_link->name);
@@ -675,8 +676,10 @@ int soc_new_compress(struct snd_soc_pcm_
 
 		rtd->pcm = be_pcm;
 		rtd->fe_compr = 1;
-		be_pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream->private_data = rtd;
-		be_pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream->private_data = rtd;
+		if (rtd->dai_link->dpcm_playback)
+			be_pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream->private_data = rtd;
+		else if (rtd->dai_link->dpcm_capture)
+			be_pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream->private_data = rtd;
 		memcpy(compr->ops, &soc_compr_dyn_ops, sizeof(soc_compr_dyn_ops));
 	} else
 		memcpy(compr->ops, &soc_compr_ops, sizeof(soc_compr_ops));