Merge branch 'topic/ctl-add-remove-fixes' into for-linus

* topic/ctl-add-remove-fixes:
  sound: snd_ctl_remove_user_ctl: prevent removal of kernel controls
  sound: snd_ctl_remove_unlocked_id: simplify user control counting
  sound: snd_ctl_remove_unlocked_id: simplify error paths
  sound: snd_ctl_elem_add: fix value count check
This commit is contained in:
Takashi Iwai 2009-09-10 15:32:47 +02:00
commit f604529d0c
1 changed files with 17 additions and 17 deletions

View File

@ -414,7 +414,7 @@ int snd_ctl_remove_id(struct snd_card *card, struct snd_ctl_elem_id *id)
EXPORT_SYMBOL(snd_ctl_remove_id); EXPORT_SYMBOL(snd_ctl_remove_id);
/** /**
* snd_ctl_remove_unlocked_id - remove the unlocked control of the given id and release it * snd_ctl_remove_user_ctl - remove and release the unlocked user control
* @file: active control handle * @file: active control handle
* @id: the control id to remove * @id: the control id to remove
* *
@ -423,7 +423,7 @@ EXPORT_SYMBOL(snd_ctl_remove_id);
* *
* Returns 0 if successful, or a negative error code on failure. * Returns 0 if successful, or a negative error code on failure.
*/ */
static int snd_ctl_remove_unlocked_id(struct snd_ctl_file * file, static int snd_ctl_remove_user_ctl(struct snd_ctl_file * file,
struct snd_ctl_elem_id *id) struct snd_ctl_elem_id *id)
{ {
struct snd_card *card = file->card; struct snd_card *card = file->card;
@ -433,15 +433,23 @@ static int snd_ctl_remove_unlocked_id(struct snd_ctl_file * file,
down_write(&card->controls_rwsem); down_write(&card->controls_rwsem);
kctl = snd_ctl_find_id(card, id); kctl = snd_ctl_find_id(card, id);
if (kctl == NULL) { if (kctl == NULL) {
up_write(&card->controls_rwsem); ret = -ENOENT;
return -ENOENT; goto error;
}
if (!(kctl->vd[0].access & SNDRV_CTL_ELEM_ACCESS_USER)) {
ret = -EINVAL;
goto error;
} }
for (idx = 0; idx < kctl->count; idx++) for (idx = 0; idx < kctl->count; idx++)
if (kctl->vd[idx].owner != NULL && kctl->vd[idx].owner != file) { if (kctl->vd[idx].owner != NULL && kctl->vd[idx].owner != file) {
up_write(&card->controls_rwsem); ret = -EBUSY;
return -EBUSY; goto error;
} }
ret = snd_ctl_remove(card, kctl); ret = snd_ctl_remove(card, kctl);
if (ret < 0)
goto error;
card->user_ctl_count--;
error:
up_write(&card->controls_rwsem); up_write(&card->controls_rwsem);
return ret; return ret;
} }
@ -951,7 +959,7 @@ static int snd_ctl_elem_add(struct snd_ctl_file *file,
if (card->user_ctl_count >= MAX_USER_CONTROLS) if (card->user_ctl_count >= MAX_USER_CONTROLS)
return -ENOMEM; return -ENOMEM;
if (info->count > 1024) if (info->count < 1)
return -EINVAL; return -EINVAL;
access = info->access == 0 ? SNDRV_CTL_ELEM_ACCESS_READWRITE : access = info->access == 0 ? SNDRV_CTL_ELEM_ACCESS_READWRITE :
(info->access & (SNDRV_CTL_ELEM_ACCESS_READWRITE| (info->access & (SNDRV_CTL_ELEM_ACCESS_READWRITE|
@ -1052,18 +1060,10 @@ static int snd_ctl_elem_remove(struct snd_ctl_file *file,
struct snd_ctl_elem_id __user *_id) struct snd_ctl_elem_id __user *_id)
{ {
struct snd_ctl_elem_id id; struct snd_ctl_elem_id id;
int err;
if (copy_from_user(&id, _id, sizeof(id))) if (copy_from_user(&id, _id, sizeof(id)))
return -EFAULT; return -EFAULT;
err = snd_ctl_remove_unlocked_id(file, &id); return snd_ctl_remove_user_ctl(file, &id);
if (! err) {
struct snd_card *card = file->card;
down_write(&card->controls_rwsem);
card->user_ctl_count--;
up_write(&card->controls_rwsem);
}
return err;
} }
static int snd_ctl_subscribe_events(struct snd_ctl_file *file, int __user *ptr) static int snd_ctl_subscribe_events(struct snd_ctl_file *file, int __user *ptr)