Skip to contentSkip to conversation

Input: refuse to register absolute devices without absinfo

PATCH In review Dmitry Torokhov 3 participants 3 messages Jan 31, 2017 – Feb 1, 2017

Subsystems (2)
HID Input drivers
lore
Share & tools
lore

Dmitry Torokhov

author maintainer
#0 lore raw

PATCH 1/1 Input: refuse to register absolute devices without absinfo

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 <[email protected]>
---
 drivers/input/input.c | 6 ++++++
 1 file changed, 6 insertions(+)
drivers/input/input.c +6 -0
index f0d2d45a68e3..4617f2db9e36 100644
@@ -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);
Signature · 5 lines
2.11.0.483.g087da7b7c-goog


-- 
Dmitry
Reviewed-by on v1 1/1
#1 lore raw
Quoted 7 lines · Dmitry Torokhov

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 <[email protected]>

---

Looks good to me:

Reviewed-by Benjamin Tissoires <[email protected]>

Cheers,
Benjamin

Quoted 26 lines
 drivers/input/input.c | 6 ++++++
 1 file changed, 6 insertions(+)
drivers/input/input.c +6 -0
index f0d2d45a68e3..4617f2db9e36 100644
@@ -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);
Signature · 5 lines
2.11.0.483.g087da7b7c-goog


-- 
Dmitry
maintainer Acked-by on v1 1/1
#2 lore raw
In reply to Dmitry Torokhov
Quoted 6 lines · Dmitry Torokhov

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 <[email protected]>
Acked-by Jiri Kosina <[email protected]>

Thanks.

Signature · 2 lines
Jiri Kosina
SUSE Labs