From: José Expósito <jose.exposito89@gmail.com>
Date: Wed, 5 Jan 2022 17:29:15 +0000 (+0100)
Subject: HID: hid-uclogic-params: Invalid parameter check in uclogic_params_frame_init_v1_butt... 
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=0fc97f944245de471cbabf637fd84036939e009a;p=linux.git

HID: hid-uclogic-params: Invalid parameter check in uclogic_params_frame_init_v1_buttonpad

[ Upstream commit aa320fdbbbb482c19100f51461bd0069753ce3d7 ]

The function performs a check on the hdev input parameters, however, it
is used before the check.

Initialize the udev variable after the sanity check to avoid a
possible NULL pointer dereference.

Fixes: 9614219e9310e ("HID: uclogic: Extract tablet parameter discovery into a module")
Addresses-Coverity-ID: 1443763 ("Null pointer dereference")
Signed-off-by: José Expósito <jose.exposito89@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

diff --git a/drivers/hid/hid-uclogic-params.c b/drivers/hid/hid-uclogic-params.c
index 4136837e4d158..3e70f969fb849 100644
--- a/drivers/hid/hid-uclogic-params.c
+++ b/drivers/hid/hid-uclogic-params.c
@@ -452,7 +452,7 @@ static int uclogic_params_frame_init_v1_buttonpad(
 {
 	int rc;
 	bool found = false;
-	struct usb_device *usb_dev = hid_to_usb_dev(hdev);
+	struct usb_device *usb_dev;
 	char *str_buf = NULL;
 	const size_t str_len = 16;
 
@@ -462,6 +462,8 @@ static int uclogic_params_frame_init_v1_buttonpad(
 		goto cleanup;
 	}
 
+	usb_dev = hid_to_usb_dev(hdev);
+
 	/*
 	 * Enable generic button mode
 	 */