Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org, Pan Bian <bianpan2016@163.com>,
        Dmitry Torokhov <dmitry.torokhov@gmail.com>,
        Sasha Levin <sashal@kernel.org>
Subject: [PATCH 4.19 062/113] Input: synaptics-rmi4 - fix possible double free
Date:   Wed, 15 May 2019 12:55:53 +0200
Message-Id: <20190515090658.270679295@linuxfoundation.org>
In-Reply-To: <20190515090652.640988966@linuxfoundation.org>
References: <20190515090652.640988966@linuxfoundation.org>
User-Agent: quilt/0.66
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

[ Upstream commit bce1a78423961fce676ac65540a31b6ffd179e6d ]

The RMI4 function structure has been released in rmi_register_function
if error occurs. However, it will be released again in the function
rmi_create_function, which may result in a double-free bug.

Signed-off-by: Pan Bian <bianpan2016@163.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/input/rmi4/rmi_driver.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/drivers/input/rmi4/rmi_driver.c b/drivers/input/rmi4/rmi_driver.c
index fc3ab93b7aea4..7fb358f961957 100644
--- a/drivers/input/rmi4/rmi_driver.c
+++ b/drivers/input/rmi4/rmi_driver.c
@@ -860,7 +860,7 @@ static int rmi_create_function(struct rmi_device *rmi_dev,
 
 	error = rmi_register_function(fn);
 	if (error)
-		goto err_put_fn;
+		return error;
 
 	if (pdt->function_number == 0x01)
 		data->f01_container = fn;
@@ -870,10 +870,6 @@ static int rmi_create_function(struct rmi_device *rmi_dev,
 	list_add_tail(&fn->node, &data->function_list);
 
 	return RMI_SCAN_CONTINUE;
-
-err_put_fn:
-	put_device(&fn->dev);
-	return error;
 }
 
 void rmi_enable_irq(struct rmi_device *rmi_dev, bool clear_wake)
-- 
2.20.1