Commit dcd7b8bd63cb81c5b973bf86510ca3c80bbbd162 ("staging: comedi: put module _after_ detach" by myself) reversed a couple of calls in `comedi_device_attach()` when recovering from an error returned by the low-level driver's 'attach' handler. Unfortunately, that introduced a NULL pointer dereference bug as `dev->driver` is NULL after the call to `comedi_device_detach()`. We still have a pointer to the low-level comedi driver structure in the `driv` variable, so use that instead.
Unified · Split
| @@ -482,7 +482,7 @@ int comedi_device_attach(struct comedi_device *dev, struct comedi_devconfig *it) · 481 unmodified lines | |||
| 482 | ret = comedi_device_postconfig(dev); | 482 | ret = comedi_device_postconfig(dev); |
| 483 | if (ret < 0) { | 483 | if (ret < 0) { |
| 484 | comedi_device_detach(dev); | 484 | comedi_device_detach(dev); |
| 485 | module_put(dev->driver->module); | 485 | module_put(driv->module); |
| 486 | } | 486 | } |
| 487 | /* On success, the driver module count has been incremented. */ | 487 | /* On success, the driver module count has been incremented. */ |
| 488 | return ret; | 488 | return ret; |