ALSA: hda: hda_component: Fix mutex crash if nothing ever binds

Move the initialization of parent->mutex into
hda_component_manager_init() so that it is always valid.

In hda_component_manager_bind() do not clear the parent information.
Only zero-fill the per-component data ready for it to be filled in
by the components as they bind.

Previously parent->mutex was being initialized only in
hda_component_manager_bind(). This meant that it was only
initialized if all components appeared and there was a bind callback.
If there wasn't a bind the mutex object was not valid when the
Realtek driver called any of the other functions.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Fixes: 047b9cbbaa8e ("ALSA: hda: hda_component: Protect shared data with a mutex")
Link: https://patch.msgid.link/20240826094940.45563-1-rf@opensource.cirrus.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/sound/pci/hda/hda_component.c b/sound/pci/hda/hda_component.c
index 7b19cb38b4e025a363435595d2d8ca03ba86cf02..b7dfdb10d15672673fc36f01e6e8cc31a3e036b1 100644 (file)
--- a/sound/pci/hda/hda_component.c
+++ b/sound/pci/hda/hda_component.c
@@ -141,8 +141,7 @@ int hda_component_manager_bind(struct hda_codec *cdc,
        int ret;
 
        /* Init shared and component specific data */
-       memset(parent, 0, sizeof(*parent));
-       mutex_init(&parent->mutex);
+       memset(parent->comps, 0, sizeof(parent->comps));
        parent->codec = cdc;
 
        mutex_lock(&parent->mutex);
@@ -164,6 +163,8 @@ int hda_component_manager_init(struct hda_codec *cdc,
        struct hda_scodec_match *sm;
        int ret, i;
 
+       mutex_init(&parent->mutex);
+
        for (i = 0; i < count; i++) {
                sm = devm_kmalloc(dev, sizeof(*sm), GFP_KERNEL);
                if (!sm)