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-rw-r--r--include/sound/core.h2
-rw-r--r--sound/core/control.c31
-rw-r--r--sound/core/init.c1
3 files changed, 28 insertions, 6 deletions
diff --git a/include/sound/core.h b/include/sound/core.h
index eedda2c..1df3f2f 100644
--- a/include/sound/core.h
+++ b/include/sound/core.h
@@ -116,6 +116,8 @@ struct snd_card {
int user_ctl_count; /* count of all user controls */
struct list_head controls; /* all controls for this card */
struct list_head ctl_files; /* active control files */
+ struct mutex user_ctl_lock; /* protects user controls against
+ concurrent access */
struct snd_info_entry *proc_root; /* root for soundcard specific files */
struct snd_info_entry *proc_id; /* the card id */
diff --git a/sound/core/control.c b/sound/core/control.c
index f038f5a..00ab034 100644
--- a/sound/core/control.c
+++ b/sound/core/control.c
@@ -991,6 +991,7 @@ static int snd_ctl_elem_unlock(struct snd_ctl_file *file,
struct user_element {
struct snd_ctl_elem_info info;
+ struct snd_card *card;
void *elem_data; /* element data */
unsigned long elem_data_size; /* size of element data in bytes */
void *tlv_data; /* TLV data */
@@ -1034,7 +1035,9 @@ static int snd_ctl_elem_user_get(struct snd_kcontrol *kcontrol,
{
struct user_element *ue = kcontrol->private_data;
+ mutex_lock(&ue->card->user_ctl_lock);
memcpy(&ucontrol->value, ue->elem_data, ue->elem_data_size);
+ mutex_unlock(&ue->card->user_ctl_lock);
return 0;
}
@@ -1043,10 +1046,12 @@ static int snd_ctl_elem_user_put(struct snd_kcontrol *kcontrol,
{
int change;
struct user_element *ue = kcontrol->private_data;
-
+
+ mutex_lock(&ue->card->user_ctl_lock);
change = memcmp(&ucontrol->value, ue->elem_data, ue->elem_data_size) != 0;
if (change)
memcpy(ue->elem_data, &ucontrol->value, ue->elem_data_size);
+ mutex_unlock(&ue->card->user_ctl_lock);
return change;
}
@@ -1066,19 +1071,32 @@ static int snd_ctl_elem_user_tlv(struct snd_kcontrol *kcontrol,
new_data = memdup_user(tlv, size);
if (IS_ERR(new_data))
return PTR_ERR(new_data);
+ mutex_lock(&ue->card->user_ctl_lock);
change = ue->tlv_data_size != size;
if (!change)
change = memcmp(ue->tlv_data, new_data, size);
kfree(ue->tlv_data);
ue->tlv_data = new_data;
ue->tlv_data_size = size;
+ mutex_unlock(&ue->card->user_ctl_lock);
} else {
- if (! ue->tlv_data_size || ! ue->tlv_data)
- return -ENXIO;
- if (size < ue->tlv_data_size)
- return -ENOSPC;
+ int ret = 0;
+
+ mutex_lock(&ue->card->user_ctl_lock);
+ if (!ue->tlv_data_size || !ue->tlv_data) {
+ ret = -ENXIO;
+ goto err_unlock;
+ }
+ if (size < ue->tlv_data_size) {
+ ret = -ENOSPC;
+ goto err_unlock;
+ }
if (copy_to_user(tlv, ue->tlv_data, ue->tlv_data_size))
- return -EFAULT;
+ ret = -EFAULT;
+err_unlock:
+ mutex_unlock(&ue->card->user_ctl_lock);
+ if (ret)
+ return ret;
}
return change;
}
@@ -1210,6 +1228,7 @@ static int snd_ctl_elem_add(struct snd_ctl_file *file,
ue = kzalloc(sizeof(struct user_element) + private_size, GFP_KERNEL);
if (ue == NULL)
return -ENOMEM;
+ ue->card = card;
ue->info = *info;
ue->info.access = 0;
ue->elem_data = (char *)ue + sizeof(*ue);
diff --git a/sound/core/init.c b/sound/core/init.c
index 5ee8384..7bdfd19 100644
--- a/sound/core/init.c
+++ b/sound/core/init.c
@@ -232,6 +232,7 @@ int snd_card_new(struct device *parent, int idx, const char *xid,
INIT_LIST_HEAD(&card->devices);
init_rwsem(&card->controls_rwsem);
rwlock_init(&card->ctl_files_rwlock);
+ mutex_init(&card->user_ctl_lock);
INIT_LIST_HEAD(&card->controls);
INIT_LIST_HEAD(&card->ctl_files);
spin_lock_init(&card->files_lock);
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