From e50b1e06b79e9d51efbff9627b4dd407184ef43f Mon Sep 17 00:00:00 2001 From: Lars-Peter Clausen Date: Mon, 6 Jul 2015 17:01:24 +0200 Subject: [PATCH] ASoC: dapm: Lock during userspace access The DAPM lock must be held when accessing the DAPM graph status through sysfs or debugfs, otherwise concurrent changes to the graph can result in undefined behaviour. Signed-off-by: Lars-Peter Clausen Signed-off-by: Mark Brown Cc: stable@vger.kernel.org --- sound/soc/soc-dapm.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/sound/soc/soc-dapm.c b/sound/soc/soc-dapm.c index a47a8ce7a5ea..1779430013ea 100644 --- a/sound/soc/soc-dapm.c +++ b/sound/soc/soc-dapm.c @@ -1952,6 +1952,7 @@ static ssize_t dapm_widget_power_read_file(struct file *file, size_t count, loff_t *ppos) { struct snd_soc_dapm_widget *w = file->private_data; + struct snd_soc_card *card = w->dapm->card; char *buf; int in, out; ssize_t ret; @@ -1961,6 +1962,8 @@ static ssize_t dapm_widget_power_read_file(struct file *file, if (!buf) return -ENOMEM; + mutex_lock(&card->dapm_mutex); + /* Supply widgets are not handled by is_connected_{input,output}_ep() */ if (w->is_supply) { in = 0; @@ -2007,6 +2010,8 @@ static ssize_t dapm_widget_power_read_file(struct file *file, p->sink->name); } + mutex_unlock(&card->dapm_mutex); + ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret); kfree(buf); @@ -2281,11 +2286,15 @@ static ssize_t dapm_widget_show(struct device *dev, struct snd_soc_pcm_runtime *rtd = dev_get_drvdata(dev); int i, count = 0; + mutex_lock(&rtd->card->dapm_mutex); + for (i = 0; i < rtd->num_codecs; i++) { struct snd_soc_codec *codec = rtd->codec_dais[i]->codec; count += dapm_widget_show_codec(codec, buf + count); } + mutex_unlock(&rtd->card->dapm_mutex); + return count; } -- 2.30.2