[media] rc: Call rc_register_device before irq setup
This should fix a potential race condition, when the irq handler
triggers while rc_register_device is still setting up the rdev->raw
device.
This crash has not been observed in practice, but there should be a very
small window where it could occur. Since ir_raw_event_store_with_filter
checks if rdev->raw is not NULL before using it, this bug is not
triggered if the request_irq triggers a pending irq directly (since
rdev->raw will still be NULL then).
This commit was tested on nuvoton-cir only.
Cc: Jarod Wilson <jarod@redhat.com>
Cc: Maxim Levitsky <maximlevitsky@gmail.com>
Cc: David Härdeman <david@hardeman.nu>
Signed-off-by: Matthijs Kooijman <matthijs@stdin.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/rc/ite-cir.c b/drivers/media/rc/ite-cir.c
index 8e0e661..e810846 100644
--- a/drivers/media/rc/ite-cir.c
+++ b/drivers/media/rc/ite-cir.c
@@ -1591,28 +1591,28 @@
rdev->driver_name = ITE_DRIVER_NAME;
rdev->map_name = RC_MAP_RC6_MCE;
+ ret = rc_register_device(rdev);
+ if (ret)
+ goto exit_free_dev_rdev;
+
ret = -EBUSY;
/* now claim resources */
if (!request_region(itdev->cir_addr,
dev_desc->io_region_size, ITE_DRIVER_NAME))
- goto exit_free_dev_rdev;
+ goto exit_unregister_device;
if (request_irq(itdev->cir_irq, ite_cir_isr, IRQF_SHARED,
ITE_DRIVER_NAME, (void *)itdev))
goto exit_release_cir_addr;
- ret = rc_register_device(rdev);
- if (ret)
- goto exit_free_irq;
-
ite_pr(KERN_NOTICE, "driver has been successfully loaded\n");
return 0;
-exit_free_irq:
- free_irq(itdev->cir_irq, itdev);
exit_release_cir_addr:
release_region(itdev->cir_addr, itdev->params.io_region_size);
+exit_unregister_device:
+ rc_unregister_device(rdev);
exit_free_dev_rdev:
rc_free_device(rdev);
kfree(itdev);