Input: fix open/close races in joystick drivers - add a semaphore
to the ones that register more than one input device.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
diff --git a/drivers/input/joystick/gamecon.c b/drivers/input/joystick/gamecon.c
index 462fc38..95bbdd3 100644
--- a/drivers/input/joystick/gamecon.c
+++ b/drivers/input/joystick/gamecon.c
@@ -81,6 +81,7 @@
struct timer_list timer;
unsigned char pads[GC_MAX + 1];
int used;
+ struct semaphore sem;
char phys[5][32];
};
@@ -503,22 +504,33 @@
static int gc_open(struct input_dev *dev)
{
struct gc *gc = dev->private;
+ int err;
+
+ err = down_interruptible(&gc->sem);
+ if (err)
+ return err;
+
if (!gc->used++) {
parport_claim(gc->pd);
parport_write_control(gc->pd->port, 0x04);
mod_timer(&gc->timer, jiffies + GC_REFRESH_TIME);
}
+
+ up(&gc->sem);
return 0;
}
static void gc_close(struct input_dev *dev)
{
struct gc *gc = dev->private;
+
+ down(&gc->sem);
if (!--gc->used) {
- del_timer(&gc->timer);
+ del_timer_sync(&gc->timer);
parport_write_control(gc->pd->port, 0x00);
parport_release(gc->pd);
}
+ up(&gc->sem);
}
static struct gc __init *gc_probe(int *config, int nargs)
@@ -542,11 +554,12 @@
return NULL;
}
- if (!(gc = kmalloc(sizeof(struct gc), GFP_KERNEL))) {
+ if (!(gc = kcalloc(1, sizeof(struct gc), GFP_KERNEL))) {
parport_put_port(pp);
return NULL;
}
- memset(gc, 0, sizeof(struct gc));
+
+ init_MUTEX(&gc->sem);
gc->pd = parport_register_device(pp, "gamecon", NULL, NULL, NULL, PARPORT_DEV_EXCL, NULL);