Input: synaptics-rmi4 - fix UAF of IRQ domain on driver removal

Calling irq_domain_remove() will lead to freeing the IRQ domain
prematurely. The domain is still referenced and will be attempted to get
used via rmi_free_function_list() -> rmi_unregister_function() ->
irq_dispose_mapping() -> irq_get_irq_data()'s ->domain pointer.

With PaX's MEMORY_SANITIZE this will lead to an access fault when
attempting to dereference embedded pointers, as in Torsten's report that
was faulting on the 'domain->ops->unmap' test.

Fix this by releasing the IRQ domain only after all related IRQs have
been deactivated.

Fixes: 24d28e4f1271 ("Input: synaptics-rmi4 - convert irq distribution to irq_domain")
Reported-by: Torsten Hilbrich <torsten.hilbrich@secunet.com>
Signed-off-by: Mathias Krause <minipli@grsecurity.net>
Link: https://lore.kernel.org/r/20240222142654.856566-1-minipli@grsecurity.net
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

diff --git a/drivers/input/rmi4/rmi_driver.c b/drivers/input/rmi4/rmi_driver.c
index 258d5fe3d395c4670088aa0d736cac69c7d24550..42eaebb3bf5cc82efabccff777a8ee23b016bf49 100644 (file)
--- a/drivers/input/rmi4/rmi_driver.c
+++ b/drivers/input/rmi4/rmi_driver.c
@@ -978,12 +978,12 @@ static int rmi_driver_remove(struct device *dev)
 
        rmi_disable_irq(rmi_dev, false);
 
-       irq_domain_remove(data->irqdomain);
-       data->irqdomain = NULL;
-
        rmi_f34_remove_sysfs(rmi_dev);
        rmi_free_function_list(rmi_dev);
 
+       irq_domain_remove(data->irqdomain);
+       data->irqdomain = NULL;
+
        return 0;
 }