From: Jaroslav Kysela <perex@perex.cz>
Date: Thu, 20 Mar 2025 20:55:23 +0000 (+0100)
Subject: seq: add more checks to snd_seq_hw_set_client_info for older kernels
X-Git-Tag: v1.2.14~19
X-Git-Url: https://git.alsa-project.org/?a=commitdiff_plain;h=1b9a073e6a4e56a0faf75188966968621abd0786;p=alsa-lib.git

seq: add more checks to snd_seq_hw_set_client_info for older kernels

The snd_seq_set_client_midi_version() should fail for older kernel
when applications are trying to configure new midi versions.

BugLink: https://gitlab.freedesktop.org/pipewire/pipewire/-/issues/4621
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
---

diff --git a/src/seq/seq_hw.c b/src/seq/seq_hw.c
index e88a7b22..5e9b8953 100644
--- a/src/seq/seq_hw.c
+++ b/src/seq/seq_hw.c
@@ -125,6 +125,15 @@ static int snd_seq_hw_set_client_info(snd_seq_t *seq, snd_seq_client_info_t * in
 {
 	snd_seq_hw_t *hw = seq->private_data;
 
+	/* added fields are not checked on older kernels */
+	if (SNDRV_PROTOCOL_VERSION(1, 0, 3) > hw->version) {
+		if (info->midi_version > 0)
+			return -EINVAL;
+		if (info->filter & SNDRV_SEQ_FILTER_NO_CONVERT)
+			return -EINVAL;
+		if (info->group_filter != 0)
+			return -EINVAL;
+	}
 	if (ioctl(hw->fd, SNDRV_SEQ_IOCTL_SET_CLIENT_INFO, info) < 0) {
 		/*SYSERR("SNDRV_SEQ_IOCTL_SET_CLIENT_INFO failed");*/
 		return -errno;