[PATCH] USB Elan FTDI: check for workqueue creation

From: Cyrill Gorcunov
Date: Mon Feb 19 2007 - 13:18:54 EST


This patch prevents from NULL pointer usage if
workqueue creation failed.

Signed-off-by: Cyrill Gorcunov <gorcunov@xxxxxxxxx>

---

drivers/usb/misc/ftdi-elan.c | 24 +++++++++++++++++++-----
1 files changed, 19 insertions(+), 5 deletions(-)

diff --git a/drivers/usb/misc/ftdi-elan.c b/drivers/usb/misc/ftdi-elan.c
index 0c1d66d..67a25e9 100644
--- a/drivers/usb/misc/ftdi-elan.c
+++ b/drivers/usb/misc/ftdi-elan.c
@@ -57,9 +57,9 @@ module_param(distrust_firmware, bool, 0);
MODULE_PARM_DESC(distrust_firmware, "true to distrust firmware power/overcurren"
"t setup");
extern struct platform_driver u132_platform_driver;
-static struct workqueue_struct *status_queue;
-static struct workqueue_struct *command_queue;
-static struct workqueue_struct *respond_queue;
+static struct workqueue_struct *status_queue = NULL;
+static struct workqueue_struct *command_queue = NULL;
+static struct workqueue_struct *respond_queue = NULL;
/*
* ftdi_module_lock exists to protect access to global variables
*
@@ -2905,17 +2905,31 @@ static int __init ftdi_elan_init(void)
{
int result;
printk(KERN_INFO "driver %s built at %s on %s\n", ftdi_elan_driver.name,
- __TIME__, __DATE__);
+ __TIME__, __DATE__);
init_MUTEX(&ftdi_module_lock);
INIT_LIST_HEAD(&ftdi_static_list);
status_queue = create_singlethread_workqueue("ftdi-status-control");
+ if (!status_queue)
+ goto err1;
command_queue = create_singlethread_workqueue("ftdi-command-engine");
+ if (!command_queue)
+ goto err2;
respond_queue = create_singlethread_workqueue("ftdi-respond-engine");
+ if (!respond_queue)
+ goto err3;
result = usb_register(&ftdi_elan_driver);
if (result)
printk(KERN_ERR "usb_register failed. Error number %d\n",
- result);
+ result);
return result;
+
+ err3:
+ destroy_workqueue(command_queue);
+ err2:
+ destroy_workqueue(status_queue);
+ err1:
+ printk(KERN_ERR "%s couldn't create workqueue\n", ftdi_elan_driver.name);
+ return -ENOMEM;
}

static void __exit ftdi_elan_exit(void)
-
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