From 7c7335877105364f7f5181e80ff34206b54be81f Mon Sep 17 00:00:00 2001 From: Clemens Ladisch Date: Mon, 7 Mar 2011 13:22:50 +0100 Subject: [PATCH] ALSA: control: fix numid conflict check for new controls The purpose of the snd_ctl_hole_check() function is to find conflicts between the numerical IDs of the new control and those of any existing controls. However, it would fail to detect an existing control whose count is smaller than the new control's count and whose interval of IDs is entirely contained in the interval of the new control's IDs. To fix this, use the correct formula to detect overlapping intervals, which happens to simplify the condition. This problem was not encountered so far because ALSA does not yet allow drivers to allocate specific control IDs. Signed-off-by: Clemens Ladisch Signed-off-by: Takashi Iwai --- sound/core/control.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/sound/core/control.c b/sound/core/control.c index 9ce00ed20fba..d1b5ce818a4f 100644 --- a/sound/core/control.c +++ b/sound/core/control.c @@ -285,10 +285,8 @@ static unsigned int snd_ctl_hole_check(struct snd_card *card, struct snd_kcontrol *kctl; list_for_each_entry(kctl, &card->controls, list) { - if ((kctl->id.numid <= card->last_numid && - kctl->id.numid + kctl->count > card->last_numid) || - (kctl->id.numid <= card->last_numid + count - 1 && - kctl->id.numid + kctl->count > card->last_numid + count - 1)) + if (kctl->id.numid < card->last_numid + 1 + count && + kctl->id.numid + kctl->count > card->last_numid + 1) return card->last_numid = kctl->id.numid + kctl->count - 1; } return card->last_numid; -- 2.30.2