diff options
| -rw-r--r-- | drivers/staging/comedi/comedi_fops.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/drivers/staging/comedi/comedi_fops.c b/drivers/staging/comedi/comedi_fops.c index 1464f550a5a..fbd3d1c6c64 100644 --- a/drivers/staging/comedi/comedi_fops.c +++ b/drivers/staging/comedi/comedi_fops.c @@ -104,9 +104,13 @@ static int comedi_ioctl(struct inode *inode, struct file *file, const unsigned minor = iminor(file->f_dentry->d_inode); struct comedi_device_file_info *dev_file_info = comedi_get_device_file_info(minor); - comedi_device *dev = dev_file_info->device; + comedi_device *dev; int rc; + if (dev_file_info == NULL || dev_file_info->device == NULL) + return -ENODEV; + dev = dev_file_info->device; + mutex_lock(&dev->mutex); /* Device config is special, because it must work on |