Patch "ASoC: topology: Add missing rwsem around snd_ctl_remove() calls" has been added to the 4.4-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    ASoC: topology: Add missing rwsem around snd_ctl_remove() calls

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     asoc-topology-add-missing-rwsem-around-snd_ctl_remov.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 0c763d8c72d2fa9505965186b9c641551dc7ca68
Author: Takashi Iwai <tiwai@xxxxxxx>
Date:   Tue Nov 16 08:18:12 2021 +0100

    ASoC: topology: Add missing rwsem around snd_ctl_remove() calls
    
    [ Upstream commit 7e567b5ae06315ef2d70666b149962e2bb4b97af ]
    
    snd_ctl_remove() has to be called with card->controls_rwsem held (when
    called after the card instantiation).  This patch add the missing
    rwsem calls around it.
    
    Fixes: 8a9782346dcc ("ASoC: topology: Add topology core")
    Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
    Link: https://lore.kernel.org/r/20211116071812.18109-1-tiwai@xxxxxxx
    Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/sound/soc/soc-topology.c b/sound/soc/soc-topology.c
index 0675ab3fec6c7..ff12f2aa4e51d 100644
--- a/sound/soc/soc-topology.c
+++ b/sound/soc/soc-topology.c
@@ -1831,6 +1831,7 @@ EXPORT_SYMBOL_GPL(snd_soc_tplg_widget_remove_all);
 /* remove dynamic controls from the component driver */
 int snd_soc_tplg_component_remove(struct snd_soc_component *comp, u32 index)
 {
+	struct snd_card *card = comp->card->snd_card;
 	struct snd_soc_dobj *dobj, *next_dobj;
 	int pass = SOC_TPLG_PASS_END;
 
@@ -1838,6 +1839,7 @@ int snd_soc_tplg_component_remove(struct snd_soc_component *comp, u32 index)
 	while (pass >= SOC_TPLG_PASS_START) {
 
 		/* remove mixer controls */
+		down_write(&card->controls_rwsem);
 		list_for_each_entry_safe(dobj, next_dobj, &comp->dobj_list,
 			list) {
 
@@ -1870,6 +1872,7 @@ int snd_soc_tplg_component_remove(struct snd_soc_component *comp, u32 index)
 				break;
 			}
 		}
+		up_write(&card->controls_rwsem);
 		pass--;
 	}