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.
Signed-off-by: Takashi Iwai tiwai@suse.de --- sound/core/seq/seq_clientmgr.c | 12 ++++++++---- sound/core/seq/seq_ports.c | 24 ++++++++++++++++-------- sound/core/seq/seq_ports.h | 5 +++-- 3 files changed, 27 insertions(+), 14 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..188262b04b72 100644 --- a/sound/core/seq/seq_ports.c +++ b/sound/core/seq/seq_ports.c @@ -107,28 +107,30 @@ 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; @@ -143,6 +145,10 @@ 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 +159,12 @@ 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);