6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Takashi Iwai <tiwai@xxxxxxx>
[ Upstream commit e77aa4b2eaa7fb31b2a7a50214ecb946b2a8b0f6 ]
When a destination client is a user client in the legacy MIDI mode and
it sets the no-UMP-conversion flag, currently the all UMP events are
still passed as-is. But this may confuse the user-space, because the
event packet size is different from the legacy mode.
Since we cannot handle UMP events in user clients unless it's running
in the UMP client mode, we should filter out those events instead of
accepting blindly. This patch addresses it by slightly adjusting the
conditions for UMP event handling at the event delivery time.
Fixes: 329ffe11a014 ("ALSA: seq: Allow suppressing UMP conversions")
Link: https://lore.kernel.org/b77a2cd6-7b59-4eb0-a8db-22d507d3af5f@xxxxxxxxx
Link: https://patch.msgid.link/20250217170034.21930-1-tiwai@xxxxxxx
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
sound/core/seq/seq_clientmgr.c | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)
diff --git a/sound/core/seq/seq_clientmgr.c b/sound/core/seq/seq_clientmgr.c
index 8b7dfbc8e8207..54931ad0dc990 100644
--- a/sound/core/seq/seq_clientmgr.c
+++ b/sound/core/seq/seq_clientmgr.c
@@ -682,12 +682,18 @@ static int snd_seq_deliver_single_event(struct snd_seq_client *client,
dest_port->time_real);
#if IS_ENABLED(CONFIG_SND_SEQ_UMP)
- if (!(dest->filter & SNDRV_SEQ_FILTER_NO_CONVERT)) {
- if (snd_seq_ev_is_ump(event)) {
+ if (snd_seq_ev_is_ump(event)) {
+ if (!(dest->filter & SNDRV_SEQ_FILTER_NO_CONVERT)) {
result = snd_seq_deliver_from_ump(client, dest, dest_port,
event, atomic, hop);
goto __skip;
- } else if (snd_seq_client_is_ump(dest)) {
+ } else if (dest->type == USER_CLIENT &&
+ !snd_seq_client_is_ump(dest)) {
+ result = 0; // drop the event
+ goto __skip;
+ }
+ } else if (snd_seq_client_is_ump(dest)) {
+ if (!(dest->filter & SNDRV_SEQ_FILTER_NO_CONVERT)) {
result = snd_seq_deliver_to_ump(client, dest, dest_port,
event, atomic, hop);
goto __skip;
--
2.39.5
