We didn't check if a port with the given port number has been already
present at creating a new port. Check it and return -EBUSY properly
if the port number conflicts.
Reviewed-by: Jaroslav Kysela <perex@xxxxxxxx>
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
---
sound/core/seq/seq_clientmgr.c | 12 ++++++++----
sound/core/seq/seq_ports.c | 25 ++++++++++++++++---------
sound/core/seq/seq_ports.h | 5 +++--
3 files changed, 27 insertions(+), 15 deletions(-)
diff --git a/sound/core/seq/seq_clientmgr.c b/sound/core/seq/seq_clientmgr.c
index 019af1343325..06743114cabf 100644
--- a/sound/core/seq/seq_clientmgr.c
+++ b/sound/core/seq/seq_clientmgr.c
@@ -1194,15 +1194,19 @@ static int snd_seq_ioctl_create_port(struct snd_seq_client *client, void *arg)
struct snd_seq_port_info *info = arg;
struct snd_seq_client_port *port;
struct snd_seq_port_callback *callback;
- int port_idx;
+ int port_idx, err;
/* it is not allowed to create the port for an another client */
if (info->addr.client != client->number)
return -EPERM;
- port = snd_seq_create_port(client, (info->flags & SNDRV_SEQ_PORT_FLG_GIVEN_PORT) ? info->addr.port : -1);
- if (port == NULL)
- return -ENOMEM;
+ if (info->flags & SNDRV_SEQ_PORT_FLG_GIVEN_PORT)
+ port_idx = info->addr.port;
+ else
+ port_idx = -1;
+ err = snd_seq_create_port(client, port_idx, &port);
+ if (err < 0)
+ return err;
if (client->type == USER_CLIENT && info->kernel) {
port_idx = port->addr.port;
diff --git a/sound/core/seq/seq_ports.c b/sound/core/seq/seq_ports.c
index 25fcf5a2c71c..500b1a5a9679 100644
--- a/sound/core/seq/seq_ports.c
+++ b/sound/core/seq/seq_ports.c
@@ -107,33 +107,34 @@ static void port_subs_info_init(struct snd_seq_port_subs_info *grp)
}
-/* create a port, port number is returned (-1 on failure);
+/* create a port, port number or a negative error code is returned
* the caller needs to unref the port via snd_seq_port_unlock() appropriately
*/
-struct snd_seq_client_port *snd_seq_create_port(struct snd_seq_client *client,
- int port)
+int snd_seq_create_port(struct snd_seq_client *client, int port,
+ struct snd_seq_client_port **port_ret)
{
struct snd_seq_client_port *new_port, *p;
- int num = -1;
+ int num;
+ *port_ret = NULL;
+
/* sanity check */
if (snd_BUG_ON(!client))
- return NULL;
+ return -EINVAL;
if (client->num_ports >= SNDRV_SEQ_MAX_PORTS) {
pr_warn("ALSA: seq: too many ports for client %d\n", client->number);
- return NULL;
+ return -EINVAL;
}
/* create a new port */
new_port = kzalloc(sizeof(*new_port), GFP_KERNEL);
if (!new_port)
- return NULL; /* failure, out of memory */
+ return -ENOMEM; /* failure, out of memory */
/* init port data */
new_port->addr.client = client->number;
new_port->addr.port = -1;
new_port->owner = THIS_MODULE;
- sprintf(new_port->name, "port-%d", num);
snd_use_lock_init(&new_port->use_lock);
port_subs_info_init(&new_port->c_src);
port_subs_info_init(&new_port->c_dest);
@@ -143,6 +144,10 @@ struct snd_seq_client_port *snd_seq_create_port(struct snd_seq_client *client,
mutex_lock(&client->ports_mutex);
write_lock_irq(&client->ports_lock);
list_for_each_entry(p, &client->ports_list_head, list) {
+ if (p->addr.port == port) {
+ num = -EBUSY;
+ goto unlock;
+ }
if (p->addr.port > num)
break;
if (port < 0) /* auto-probe mode */
@@ -153,10 +158,12 @@ struct snd_seq_client_port *snd_seq_create_port(struct snd_seq_client *client,
client->num_ports++;
new_port->addr.port = num; /* store the port number in the port */
sprintf(new_port->name, "port-%d", num);
+ *port_ret = new_port;
+ unlock:
write_unlock_irq(&client->ports_lock);
mutex_unlock(&client->ports_mutex);
- return new_port;
+ return num;
}
/* */
diff --git a/sound/core/seq/seq_ports.h b/sound/core/seq/seq_ports.h
index b1f2c4943174..44f0e9e96bbf 100644
--- a/sound/core/seq/seq_ports.h
+++ b/sound/core/seq/seq_ports.h
@@ -86,8 +86,9 @@ struct snd_seq_client_port *snd_seq_port_query_nearest(struct snd_seq_client *cl
/* unlock the port */
#define snd_seq_port_unlock(port) snd_use_lock_free(&(port)->use_lock)
-/* create a port, port number is returned (-1 on failure) */
-struct snd_seq_client_port *snd_seq_create_port(struct snd_seq_client *client, int port_index);
+/* create a port, port number or a negative error code is returned */
+int snd_seq_create_port(struct snd_seq_client *client, int port_index,
+ struct snd_seq_client_port **port_ret);
/* delete a port */
int snd_seq_delete_port(struct snd_seq_client *client, int port);
--
2.35.3
