From 0a94131d6920916ccb6a357037c535533af08819 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jos=C3=A9=20Exp=C3=B3sito?= <jose.exposito89@gmail.com>
Date: Wed, 5 Jan 2022 18:29:13 +0100
Subject: [PATCH] HID: hid-uclogic-params: Invalid parameter check in uclogic_params_get_str_desc
Mime-version: 1.0
Content-type: text/plain; charset=UTF-8
Content-transfer-encoding: 8bit
Git-commit: 0a94131d6920916ccb6a357037c535533af08819
Patch-mainline: v5.17-rc1
References: git-fixes
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: 1443827 ("Null pointer dereference")
Signed-off-by: José Expósito <jose.exposito89@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/hid/hid-uclogic-params.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/hid/hid-uclogic-params.c b/drivers/hid/hid-uclogic-params.c
index 3c10b858cf74..3a83e2c39b4f 100644
--- a/drivers/hid/hid-uclogic-params.c
+++ b/drivers/hid/hid-uclogic-params.c
@@ -66,7 +66,7 @@ static int uclogic_params_get_str_desc(__u8 **pbuf, struct hid_device *hdev,
__u8 idx, size_t len)
{
int rc;
- struct usb_device *udev = hid_to_usb_dev(hdev);
+ struct usb_device *udev;
__u8 *buf = NULL;
/* Check arguments */
@@ -75,6 +75,8 @@ static int uclogic_params_get_str_desc(__u8 **pbuf, struct hid_device *hdev,
goto cleanup;
}
+ udev = hid_to_usb_dev(hdev);
+
buf = kmalloc(len, GFP_KERNEL);
if (buf == NULL) {
rc = -ENOMEM;
--
2.31.1