From 219df32faec97349516c29f33008fea59a46e99a Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Mon, 3 Nov 2008 08:17:05 +0100 Subject: ALSA: rawmidi - Add open check in rawmidi callbacks The drivers (e.g. mtpav) may call rawmidi functions in irq handlers even though the streams are not opened. This results in Oops or panic. This patch adds the rawmidi state check before actually operating the rawmidi buffers. Tested-by: Ingo Molnar Signed-off-by: Takashi Iwai --- sound/core/rawmidi.c | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'sound/core') diff --git a/sound/core/rawmidi.c b/sound/core/rawmidi.c index c4995c9f573..39672f68ce5 100644 --- a/sound/core/rawmidi.c +++ b/sound/core/rawmidi.c @@ -148,6 +148,8 @@ static int snd_rawmidi_runtime_free(struct snd_rawmidi_substream *substream) static inline void snd_rawmidi_output_trigger(struct snd_rawmidi_substream *substream,int up) { + if (!substream->opened) + return; if (up) { tasklet_hi_schedule(&substream->runtime->tasklet); } else { @@ -158,6 +160,8 @@ static inline void snd_rawmidi_output_trigger(struct snd_rawmidi_substream *subs static void snd_rawmidi_input_trigger(struct snd_rawmidi_substream *substream, int up) { + if (!substream->opened) + return; substream->ops->trigger(substream, up); if (!up && substream->runtime->event) tasklet_kill(&substream->runtime->tasklet); @@ -857,6 +861,8 @@ int snd_rawmidi_receive(struct snd_rawmidi_substream *substream, int result = 0, count1; struct snd_rawmidi_runtime *runtime = substream->runtime; + if (!substream->opened) + return -EBADFD; if (runtime->buffer == NULL) { snd_printd("snd_rawmidi_receive: input is not active!!!\n"); return -EINVAL; @@ -1126,6 +1132,8 @@ int snd_rawmidi_transmit_ack(struct snd_rawmidi_substream *substream, int count) int snd_rawmidi_transmit(struct snd_rawmidi_substream *substream, unsigned char *buffer, int count) { + if (!substream->opened) + return -EBADFD; count = snd_rawmidi_transmit_peek(substream, buffer, count); if (count < 0) return count; -- cgit v1.2.3