[PATCH 22/36] ALSA: seq: Prohibit creating ports with special numbers

From: Takashi Iwai
Date: Fri May 19 2023 - 05:32:47 EST


Some port numbers are special, such as 254 for subscribers and 255 for
broadcast. Return error if application tries to create such a port.

Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
---
sound/core/seq/seq_clientmgr.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/sound/core/seq/seq_clientmgr.c b/sound/core/seq/seq_clientmgr.c
index 2dac8c3355fd..0f26f20596d7 100644
--- a/sound/core/seq/seq_clientmgr.c
+++ b/sound/core/seq/seq_clientmgr.c
@@ -1206,6 +1206,8 @@ static int snd_seq_ioctl_create_port(struct snd_seq_client *client, void *arg)
port_idx = info->addr.port;
else
port_idx = -1;
+ if (port_idx >= SNDRV_SEQ_ADDRESS_UNKNOWN)
+ return -EINVAL;
err = snd_seq_create_port(client, port_idx, &port);
if (err < 0)
return err;
--
2.35.3