clear-pkgs-linux-iot-lts2018/0426-ASoC-soc-pcm-Fix-FE-and-BE-race-when-accessing-subst.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: xiao jin <jin.xiao@intel.com>
Date: Thu, 12 Apr 2018 17:32:04 +0530
Subject: [PATCH] ASoC: soc-pcm: Fix FE and BE race when accessing
 substream->runtime

After start of FE and BE, FE might close without triggering
STOP, and substream->runtime gets freed. However, BE remains
at START state and BE's substream->runtime still points to the
freed runtime.

Later if FE gets opened/started again, and triggers STOP, then
skl_platform_pcm_trigger accesses the freed old runtime data.

Fix is by assigning be_substream->runtime in dpcm_be_dai_startup
when BE's state is START.

Change-Id: If1fd0464a3c6c2a3e22c8b2af7ccc68c801e0e80
Signed-off-by: Mohit Sinha <mohit.sinha@intel.com>
Signed-off-by: xiao jin <jin.xiao@intel.com>
Reviewed-on:
Reviewed-by: Shaik, Kareem M <kareem.m.shaik@intel.com>
Reviewed-by: Gogineni, GiribabuX <giribabux.gogineni@intel.com>
Reviewed-by: Shaik, ShahinaX <shahinax.shaik@intel.com>
Reviewed-by: Kesapragada, Pardha Saradhi <pardha.saradhi.kesapragada@intel.com>
Reviewed-by: Kale, Sanyog R <sanyog.r.kale@intel.com>
Tested-by: Madiwalar, MadiwalappaX <madiwalappax.madiwalar@intel.com>
---
 sound/soc/soc-pcm.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/sound/soc/soc-pcm.c b/sound/soc/soc-pcm.c
index e8b98bf..afcb2cf 100644
--- a/sound/soc/soc-pcm.c
+++ b/sound/soc/soc-pcm.c
@@ -1620,6 +1620,8 @@ int dpcm_be_dai_startup(struct snd_soc_pcm_runtime *fe, int stream)
 		if (be->dpcm[stream].users++ != 0)
 			continue;
 
+		be_substream->runtime = be->dpcm[stream].runtime;
+
 		if ((be->dpcm[stream].state != SND_SOC_DPCM_STATE_NEW) &&
 		    (be->dpcm[stream].state != SND_SOC_DPCM_STATE_CLOSE))
 			continue;
@@ -1627,7 +1629,6 @@ int dpcm_be_dai_startup(struct snd_soc_pcm_runtime *fe, int stream)
 		dev_dbg(be->dev, "ASoC: open %s BE %s\n",
 			stream ? "capture" : "playback", be->dai_link->name);
 
-		be_substream->runtime = be->dpcm[stream].runtime;
 		err = soc_pcm_open(be_substream);
 		if (err < 0) {
 			dev_err(be->dev, "ASoC: BE open failed %d\n", err);
-- 
2.21.0