ALSA: control: Add sanity checks for user ctl id name string



There was no check about the id string of user control elements, so we
accepted even a control element with an empty string, which is
obviously bogus.  This patch adds more sanity checks of id strings.

Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

parent ddb6ca75

sound/core/control.c

+4 −0

Original line number	Diff line number	Diff line
		@@ -1170,6 +1170,10 @@ static int snd_ctl_elem_add(struct snd_ctl_file *file,

		if (info->count < 1)
		return -EINVAL;
		if (!*info->id.name)
		return -EINVAL;
		if (strnlen(info->id.name, sizeof(info->id.name)) >= sizeof(info->id.name))
		return -EINVAL;
		access = info->access == 0 ? SNDRV_CTL_ELEM_ACCESS_READWRITE :
		(info->access & (SNDRV_CTL_ELEM_ACCESS_READWRITE\|
		SNDRV_CTL_ELEM_ACCESS_INACTIVE\|