[PATCH 5.4 050/102] ALSA: seq: virmidi: Fix running status after receiving sysex

From: Greg Kroah-Hartman
Date: Tue Mar 24 2020 - 09:17:45 EST


From: Takashi Iwai <tiwai@xxxxxxx>

commit 4384f167ce5fa7241b61bb0984d651bc528ddebe upstream.

The virmidi driver handles sysex event exceptionally in a short-cut
snd_seq_dump_var_event() call, but this missed the reset of the
running status. As a result, it may lead to an incomplete command
right after the sysex when an event with the same running status was
queued.

Fix it by clearing the running status properly via alling
snd_midi_event_reset_decode() for that code path.

Reported-by: Andreas Steinmetz <ast@xxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/3b4a4e0f232b7afbaf0a843f63d0e538e3029bfd.camel@xxxxxxxx
Link: https://lore.kernel.org/r/20200316090506.23966-2-tiwai@xxxxxxx
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
sound/core/seq/seq_virmidi.c | 1 +
1 file changed, 1 insertion(+)

--- a/sound/core/seq/seq_virmidi.c
+++ b/sound/core/seq/seq_virmidi.c
@@ -81,6 +81,7 @@ static int snd_virmidi_dev_receive_event
if ((ev->flags & SNDRV_SEQ_EVENT_LENGTH_MASK) != SNDRV_SEQ_EVENT_LENGTH_VARIABLE)
continue;
snd_seq_dump_var_event(ev, (snd_seq_dump_func_t)snd_rawmidi_receive, vmidi->substream);
+ snd_midi_event_reset_decode(vmidi->parser);
} else {
len = snd_midi_event_decode(vmidi->parser, msg, sizeof(msg), ev);
if (len > 0)