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From:   Miaoqian Lin <linmq006@gmail.com>
To:     Jiri Kosina <jikos@kernel.org>,
        Benjamin Tissoires <benjamin.tissoires@redhat.com>,
        Dinghao Liu <dinghao.liu@zju.edu.cn>,
        Alexandrov Stansilav <neko@nya.ai>,
        linux-input@vger.kernel.org, linux-kernel@vger.kernel.org
Cc:     linmq006@gmail.com
Subject: [PATCH] HID: elan: Fix potential double free in elan_input_configured
Date:   Sat, 16 Apr 2022 07:37:21 +0000
Message-Id: <20220416073721.3954-1-linmq006@gmail.com>
Precedence: bulk

'input' is a managed resource allocated with devm_input_allocate_device(),
so there is no need to call input_free_device() explicitly or
there will be a double free.

According to the doc of devm_input_allocate_device():
 * Managed input devices do not need to be explicitly unregistered or
 * freed as it will be done automatically when owner device unbinds from
 * its driver (or binding fails).

Fixes: b7429ea53d6c ("HID: elan: Fix memleak in elan_input_configured")
Fixes: 9a6a4193d65b ("HID: Add driver for USB ELAN Touchpad")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
---
 drivers/hid/hid-elan.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/hid/hid-elan.c b/drivers/hid/hid-elan.c
index 3091355d48df..8e4a5528e25d 100644
--- a/drivers/hid/hid-elan.c
+++ b/drivers/hid/hid-elan.c
@@ -188,7 +188,6 @@ static int elan_input_configured(struct hid_device *hdev, struct hid_input *hi)
 	ret = input_mt_init_slots(input, ELAN_MAX_FINGERS, INPUT_MT_POINTER);
 	if (ret) {
 		hid_err(hdev, "Failed to init elan MT slots: %d\n", ret);
-		input_free_device(input);
 		return ret;
 	}
 
@@ -200,7 +199,6 @@ static int elan_input_configured(struct hid_device *hdev, struct hid_input *hi)
 		hid_err(hdev, "Failed to register elan input device: %d\n",
 			ret);
 		input_mt_destroy_slots(input);
-		input_free_device(input);
 		return ret;
 	}
 
-- 
2.17.1