[PATCH AUTOSEL 4.19 022/205] ALSA: seq: Do error checks at creating system ports

From: Sasha Levin
Date: Fri Nov 08 2019 - 06:38:22 EST


From: Takashi Iwai <tiwai@xxxxxxx>

[ Upstream commit b8e131542b47b81236ecf6768c923128e1f5db6e ]

snd_seq_system_client_init() doesn't check the errors returned from
its port creations. Let's do it properly and handle the error paths.

Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
sound/core/seq/seq_system.c | 18 +++++++++++++++---
1 file changed, 15 insertions(+), 3 deletions(-)

diff --git a/sound/core/seq/seq_system.c b/sound/core/seq/seq_system.c
index 8ce1d0b40dce1..ce1f1e4727ab1 100644
--- a/sound/core/seq/seq_system.c
+++ b/sound/core/seq/seq_system.c
@@ -123,6 +123,7 @@ int __init snd_seq_system_client_init(void)
{
struct snd_seq_port_callback pcallbacks;
struct snd_seq_port_info *port;
+ int err;

port = kzalloc(sizeof(*port), GFP_KERNEL);
if (!port)
@@ -144,7 +145,10 @@ int __init snd_seq_system_client_init(void)
port->flags = SNDRV_SEQ_PORT_FLG_GIVEN_PORT;
port->addr.client = sysclient;
port->addr.port = SNDRV_SEQ_PORT_SYSTEM_TIMER;
- snd_seq_kernel_client_ctl(sysclient, SNDRV_SEQ_IOCTL_CREATE_PORT, port);
+ err = snd_seq_kernel_client_ctl(sysclient, SNDRV_SEQ_IOCTL_CREATE_PORT,
+ port);
+ if (err < 0)
+ goto error_port;

/* register announcement port */
strcpy(port->name, "Announce");
@@ -154,16 +158,24 @@ int __init snd_seq_system_client_init(void)
port->flags = SNDRV_SEQ_PORT_FLG_GIVEN_PORT;
port->addr.client = sysclient;
port->addr.port = SNDRV_SEQ_PORT_SYSTEM_ANNOUNCE;
- snd_seq_kernel_client_ctl(sysclient, SNDRV_SEQ_IOCTL_CREATE_PORT, port);
+ err = snd_seq_kernel_client_ctl(sysclient, SNDRV_SEQ_IOCTL_CREATE_PORT,
+ port);
+ if (err < 0)
+ goto error_port;
announce_port = port->addr.port;

kfree(port);
return 0;
+
+ error_port:
+ snd_seq_system_client_done();
+ kfree(port);
+ return err;
}


/* unregister our internal client */
-void __exit snd_seq_system_client_done(void)
+void snd_seq_system_client_done(void)
{
int oldsysclient = sysclient;

--
2.20.1