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From:   Jianglei Nie <niejianglei2021@163.com>
To:     ojeda@kernel.org, andriy.shevchenko@linux.intel.com,
        geert+renesas@glider.be
Cc:     linux-kernel@vger.kernel.org,
        Jianglei Nie <niejianglei2021@163.com>,
        kernel test robot <lkp@intel.com>
Subject: [PATCH v2] auxdisplay: hd44780: Fix potential memory leak in hd44780_remove()
Date:   Mon, 28 Nov 2022 16:44:21 +0800
Message-Id: <20221128084421.8626-1-niejianglei2021@163.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

hd44780_probe() allocates a memory chunk for hd with kzalloc() and
makes "lcd->drvdata->hd44780" point to it. When we call hd44780_remove(),
we should release all relevant memory and resource. But "lcd->drvdata
->hd44780" is not released, which will lead to a memory leak.

We should release the "lcd->drvdata->hd44780" in hd44780_remove() to fix
the memory leak bug.

Fixes: 41c8d0adf3c4 ("auxdisplay: hd44780: Fix memory leak on ->remove()")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Jianglei Nie <niejianglei2021@163.com>
---
 drivers/auxdisplay/hd44780.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/auxdisplay/hd44780.c b/drivers/auxdisplay/hd44780.c
index 8b2a0eb3f32a..f4800a946bd8 100644
--- a/drivers/auxdisplay/hd44780.c
+++ b/drivers/auxdisplay/hd44780.c
@@ -322,8 +322,10 @@ static int hd44780_probe(struct platform_device *pdev)
 static int hd44780_remove(struct platform_device *pdev)
 {
 	struct charlcd *lcd = platform_get_drvdata(pdev);
+	struct hd44780_common *hdc = (struct hd44780_common *)lcd->drvdata;
 
 	charlcd_unregister(lcd);
+	kfree(hdc->hd44780);
 	kfree(lcd->drvdata);
 
 	kfree(lcd);
-- 
2.25.1