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From:   Lv Yunlong <lyl2019@mail.ustc.edu.cn>
To:     han.xu@nxp.com, miquel.raynal@bootlin.com, richard@nod.at,
        vigneshr@ti.com, bbrezillon@kernel.org
Cc:     linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org,
        Lv Yunlong <lyl2019@mail.ustc.edu.cn>
Subject: [PATCH] mtd: nand: gpmi: Fix a double free in gpmi_nand_init
Date:   Fri,  2 Apr 2021 23:09:05 -0700
Message-Id: <20210403060905.5251-1-lyl2019@mail.ustc.edu.cn>
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If the callee gpmi_alloc_dma_buffer() failed to alloc memory for
this->raw_buffer, gpmi_free_dma_buffer() will be called to free
this->auxiliary_virt. But this->auxiliary_virt is still a non-NULL
and valid ptr.

Then gpmi_alloc_dma_buffer() returns err and gpmi_free_dma_buffer()
is called again to free this->auxiliary_virt in err_out. This causes
a double free.

As gpmi_free_dma_buffer() has already called in gpmi_alloc_dma_buffer's
error path, so it should return err directly instead of releasing the dma
buffer again.

Fixes: 4d02423e9afe6 ("mtd: nand: gpmi: Fix gpmi_nand_init() error path")
Signed-off-by: Lv Yunlong <lyl2019@mail.ustc.edu.cn>
---
 drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c b/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
index 3fa8c22d3f36..4d08e4ab5c1b 100644
--- a/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
+++ b/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
@@ -2449,7 +2449,7 @@ static int gpmi_nand_init(struct gpmi_nand_data *this)
 	this->bch_geometry.auxiliary_size = 128;
 	ret = gpmi_alloc_dma_buffer(this);
 	if (ret)
-		goto err_out;
+		return ret;
 
 	nand_controller_init(&this->base);
 	this->base.ops = &gpmi_nand_controller_ops;
-- 
2.25.1