[PATCH] Input: synaptics-rmi4 - validate that the rmi_dev pointer is set before dereferencing it

From: Andrew Duggan
Date: Tue Oct 22 2019 - 21:24:14 EST


A bug in hid-rmi was causing rmi_unregister_transport_device() to be
called even if the call to rmi_register_transport_device() failed to
allocate the rmi device. A patch has been submitted to fix the issue in
hid-rmi. This patch will ensure that should a simialr situation
occur then the rmi driver will not dereference a NULL pointer.

Signed-off-by: Andrew Duggan <aduggan@xxxxxxxxxxxxx>
---
drivers/input/rmi4/rmi_bus.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/input/rmi4/rmi_bus.c b/drivers/input/rmi4/rmi_bus.c
index af706a583656..6c3abae1e159 100644
--- a/drivers/input/rmi4/rmi_bus.c
+++ b/drivers/input/rmi4/rmi_bus.c
@@ -118,8 +118,10 @@ void rmi_unregister_transport_device(struct rmi_transport_dev *xport)
{
struct rmi_device *rmi_dev = xport->rmi_dev;

- device_del(&rmi_dev->dev);
- put_device(&rmi_dev->dev);
+ if (rmi_dev) {
+ device_del(&rmi_dev->dev);
+ put_device(&rmi_dev->dev);
+ }
}
EXPORT_SYMBOL(rmi_unregister_transport_device);

--
2.20.1