FAILED: patch "[PATCH] ALSA: seq: Fix UMP group 16 filtering" failed to apply to 6.6-stable tree

[<gregkh@linuxfoundation.org>]

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The patch below does not apply to the 6.6-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x 92429ca999db99febced82f23362a71b2ba4c1d8
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2026051225-snare-worshiper-0bea@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 92429ca999db99febced82f23362a71b2ba4c1d8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?C=C3=A1ssio=20Gabriel?= <cassiogabrielcontato@gmail.com>
Date: Wed, 6 May 2026 00:15:48 -0300
Subject: [PATCH] ALSA: seq: Fix UMP group 16 filtering
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The sequencer UAPI defines group_filter as an unsigned int bitmap.
Bit 0 filters groupless messages and bits 1-16 filter UMP groups 1-16.

The internal snd_seq_client storage is only unsigned short, so bit 16
is truncated when userspace sets the filter. The same truncation affects
the automatic UMP client filter used to avoid delivery to inactive
groups, so events for group 16 cannot be filtered.

Store the internal bitmap as unsigned int and keep both userspace-provided
and automatically generated values limited to the defined UAPI bits.

Fixes: d2b706077792 ("ALSA: seq: Add UMP group filter")
Cc: stable@vger.kernel.org
Signed-off-by: Cássio Gabriel <cassiogabrielcontato@gmail.com>
Link: https://patch.msgid.link/20260506-alsa-seq-ump-group16-filter-v1-1-b75160bf6993@gmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/sound/core/seq/seq_clientmgr.c b/sound/core/seq/seq_clientmgr.c
index 75a7a2af9d8c..5719637575a9 100644
--- a/sound/core/seq/seq_clientmgr.c
+++ b/sound/core/seq/seq_clientmgr.c
@@ -1253,7 +1253,7 @@ static int snd_seq_ioctl_set_client_info(struct snd_seq_client *client,
 	if (client->user_pversion >= SNDRV_PROTOCOL_VERSION(1, 0, 3))
 		client->midi_version = client_info->midi_version;
 	memcpy(client->event_filter, client_info->event_filter, 32);
-	client->group_filter = client_info->group_filter;
+	client->group_filter = client_info->group_filter & SND_SEQ_GROUP_FILTER_MASK;
 
 	/* notify the change */
 	snd_seq_system_client_ev_client_change(client->number);
diff --git a/sound/core/seq/seq_clientmgr.h b/sound/core/seq/seq_clientmgr.h
index ece02c58db70..feea8bb7d987 100644
--- a/sound/core/seq/seq_clientmgr.h
+++ b/sound/core/seq/seq_clientmgr.h
@@ -14,6 +14,9 @@
 
 /* client manager */
 
+#define SND_SEQ_GROUP_FILTER_MASK	GENMASK(SNDRV_UMP_MAX_GROUPS, 0)
+#define SND_SEQ_GROUP_FILTER_GROUPS	GENMASK(SNDRV_UMP_MAX_GROUPS, 1)
+
 struct snd_seq_user_client {
 	struct file *file;	/* file struct of client */
 	/* ... */
@@ -40,7 +43,7 @@ struct snd_seq_client {
 	int number;		/* client number */
 	unsigned int filter;	/* filter flags */
 	DECLARE_BITMAP(event_filter, 256);
-	unsigned short group_filter;
+	unsigned int group_filter;
 	snd_use_lock_t use_lock;
 	int event_lost;
 	/* ports */
diff --git a/sound/core/seq/seq_ump_client.c b/sound/core/seq/seq_ump_client.c
index fdc76f23e03f..9079ccfdc866 100644
--- a/sound/core/seq/seq_ump_client.c
+++ b/sound/core/seq/seq_ump_client.c
@@ -369,7 +369,7 @@ static void setup_client_group_filter(struct seq_ump_client *client)
 	cptr = snd_seq_kernel_client_get(client->seq_client);
 	if (!cptr)
 		return;
-	filter = ~(1U << 0); /* always allow groupless messages */
+	filter = SND_SEQ_GROUP_FILTER_GROUPS; /* always allow groupless messages */
 	for (p = 0; p < SNDRV_UMP_MAX_GROUPS; p++) {
 		if (client->ump->groups[p].active)
 			filter &= ~(1U << (p + 1));