Commit 18dd0aa5 authored Aug 17, 2009 by Clemens Ladisch Committed by Takashi Iwai Aug 17, 2009

sound: snd_ctl_remove_user_ctl: prevent removal of kernel controls



Ensure that userspace can remove only user controls.  Controls created
by kernel drivers must not be removed because they might be referenced
in calls to snd_ctl_notify().

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

parent f217ac59

sound/core/control.c

+4 −0

Original line number	Diff line number	Diff line
		@@ -436,6 +436,10 @@ static int snd_ctl_remove_user_ctl(struct snd_ctl_file * file,
		ret = -ENOENT;
		goto error;
		}
		if (!(kctl->vd[0].access & SNDRV_CTL_ELEM_ACCESS_USER)) {
		ret = -EINVAL;
		goto error;
		}
		for (idx = 0; idx < kctl->count; idx++)
		if (kctl->vd[idx].owner != NULL && kctl->vd[idx].owner != file) {
		ret = -EBUSY;