[PATCH] Input: refuse to register absolute devices without absinfo

From: Dmitry Torokhov
Date: Tue Jan 31 2017 - 18:16:14 EST


If device is supposed to send absolute events (i.e. EV_ABS bit is set in
dev->evbit) but dev->absinfo is not allocated, then the driver has done
something wrong, and we should not register such device. Otherwise we'll
crash later, when driver tries to send absolute event.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
---
drivers/input/input.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/drivers/input/input.c b/drivers/input/input.c
index f0d2d45a68e3..4617f2db9e36 100644
--- a/drivers/input/input.c
+++ b/drivers/input/input.c
@@ -2095,6 +2095,12 @@ int input_register_device(struct input_dev *dev)
const char *path;
int error;

+ if (test_bit(EV_ABS, dev->evbit) && !dev->absinfo) {
+ dev_err(&dev->dev,
+ "Absolute device without dev->absinfo, refusing to register\n");
+ return -EINVAL;
+ }
+
if (dev->devres_managed) {
devres = devres_alloc(devm_input_device_unregister,
sizeof(struct input_devres), GFP_KERNEL);
--
2.11.0.483.g087da7b7c-goog


--
Dmitry