[PATCH 5.1 42/96] ASoC: core: Fix deadlock in snd_soc_instantiate_card()

From: Greg Kroah-Hartman
Date: Mon Jul 08 2019 - 11:35:55 EST


[ Upstream commit 495f926c68ddb905a7a0192963096138c6a934e1 ]

Move the client_mutex lock to snd_soc_unbind_card() before
removing link components. This prevents the deadlock
in the error path in snd_soc_instantiate_card().

Fixes: 34ac3c3eb8 (ASoC: core: lock client_mutex while removing
link components)
Reported-by: kernelci.org bot <bot@xxxxxxxxxxxx>
Signed-off-by: Ranjani Sridharan <ranjani.sridharan@xxxxxxxxxxxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
sound/soc/soc-core.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c
index 9df3bdeb5c47..c010cc864cf3 100644
--- a/sound/soc/soc-core.c
+++ b/sound/soc/soc-core.c
@@ -1008,14 +1008,12 @@ static void soc_remove_link_components(struct snd_soc_card *card,
struct snd_soc_component *component;
struct snd_soc_rtdcom_list *rtdcom;

- mutex_lock(&client_mutex);
for_each_rtdcom(rtd, rtdcom) {
component = rtdcom->component;

if (component->driver->remove_order == order)
soc_remove_component(component);
}
- mutex_unlock(&client_mutex);
}

static void soc_remove_dai_links(struct snd_soc_card *card)
@@ -2836,12 +2834,14 @@ static void snd_soc_unbind_card(struct snd_soc_card *card, bool unregister)
snd_soc_dapm_shutdown(card);
snd_soc_flush_all_delayed_work(card);

+ mutex_lock(&client_mutex);
/* remove all components used by DAI links on this card */
for_each_comp_order(order) {
for_each_card_rtds(card, rtd) {
soc_remove_link_components(card, rtd, order);
}
}
+ mutex_unlock(&client_mutex);

soc_cleanup_card_resources(card);
if (!unregister)
--
2.20.1