[PATCH v2 4/4] hwmon: (nzxt-kraken3) Stop device IO before calling hid_hw_stop

[Guenter Roeck <linux@roeck-us.net>]

Calling hid_hw_stop() does not stop the device IO.
This results in a race condition between hid_input_report() and the point
immediately following the execution of hid_device_io_start() within
the driver probe function. If the probe operation fails after "io start"
has been initiated, this race condition will result in a UAF vulnerability.

Fix the problem by calling hid_device_io_stop() before calling
hid_hw_stop().

Reported-by: Sashiko <sashiko-bot@kernel.org>
Fixes: f3b4b146eb107 ("hwmon: Add driver for NZXT Kraken X and Z series AIO CPU coolers")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
---
v2: Call hid_device_io_stop() only if hid_device_io_start() has been called

 drivers/hwmon/nzxt-kraken3.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/hwmon/nzxt-kraken3.c b/drivers/hwmon/nzxt-kraken3.c
index d00409bcab93..05525406c5fb 100644
--- a/drivers/hwmon/nzxt-kraken3.c
+++ b/drivers/hwmon/nzxt-kraken3.c
@@ -948,7 +948,7 @@ static int kraken3_probe(struct hid_device *hdev, const struct hid_device_id *id
 	ret = kraken3_init_device(hdev);
 	if (ret < 0) {
 		hid_err(hdev, "device init failed with %d\n", ret);
-		goto fail_and_close;
+		goto fail_and_stop_io;
 	}
 
 	ret = kraken3_get_fw_ver(hdev);
@@ -960,13 +960,15 @@ static int kraken3_probe(struct hid_device *hdev, const struct hid_device_id *id
 	if (IS_ERR(priv->hwmon_dev)) {
 		ret = PTR_ERR(priv->hwmon_dev);
 		hid_err(hdev, "hwmon registration failed with %d\n", ret);
-		goto fail_and_close;
+		goto fail_and_stop_io;
 	}
 
 	kraken3_debugfs_init(priv, device_name);
 
 	return 0;
 
+fail_and_stop_io:
+	hid_device_io_stop(hdev);
 fail_and_close:
 	hid_hw_close(hdev);
 fail_and_stop:
-- 
2.45.2