staging: comedi: check s->async for poll(), read() and write()

[pandora-kernel.git] / drivers / staging / comedi / comedi_fops.c

diff --git a/drivers/staging/comedi/comedi_fops.c b/drivers/staging/comedi/comedi_fops.c
index ab9f5ed..a023f52 100644 (file)
--- a/drivers/staging/comedi/comedi_fops.c
+++ b/drivers/staging/comedi/comedi_fops.c
@@ -136,6 +136,11 @@ static long comedi_unlocked_ioctl(struct file *file, unsigned int cmd,
        /* Device config is special, because it must work on
         * an unconfigured device. */
        if (cmd == COMEDI_DEVCONFIG) {
+               if (minor >= COMEDI_NUM_BOARD_MINORS) {
+                       /* Device config not appropriate on non-board minors. */
+                       rc = -ENOTTY;
+                       goto done;
+               }
                rc = do_devconfig_ioctl(dev,
                                        (struct comedi_devconfig __user *)arg);
                goto done;
@@ -1569,7 +1574,7 @@ static unsigned int comedi_poll(struct file *file, poll_table * wait)
 
        mask = 0;
        read_subdev = comedi_get_read_subdevice(dev_file_info);
-       if (read_subdev) {
+       if (read_subdev && read_subdev->async) {
                poll_wait(file, &read_subdev->async->wait_head, wait);
                if (!read_subdev->busy
                    || comedi_buf_read_n_available(read_subdev->async) > 0
@@ -1579,7 +1584,7 @@ static unsigned int comedi_poll(struct file *file, poll_table * wait)
                }
        }
        write_subdev = comedi_get_write_subdevice(dev_file_info);
-       if (write_subdev) {
+       if (write_subdev && write_subdev->async) {
                poll_wait(file, &write_subdev->async->wait_head, wait);
                comedi_buf_write_alloc(write_subdev->async,
                                       write_subdev->async->prealloc_bufsz);
@@ -1621,7 +1626,7 @@ static ssize_t comedi_write(struct file *file, const char __user *buf,
        }
 
        s = comedi_get_write_subdevice(dev_file_info);
-       if (s == NULL) {
+       if (s == NULL || s->async == NULL) {
                retval = -EIO;
                goto done;
        }
@@ -1732,7 +1737,7 @@ static ssize_t comedi_read(struct file *file, char __user *buf, size_t nbytes,
        }
 
        s = comedi_get_read_subdevice(dev_file_info);
-       if (s == NULL) {
+       if (s == NULL || s->async == NULL) {
                retval = -EIO;
                goto done;
        }