mtd: rawnand: renesas: Add missing check after DMA map

commit 79e441e upstream.

The DMA map functions can fail and should be tested for errors.

Fixes: d8701fe ("mtd: rawnand: renesas: Add new NAND controller driver")
Cc: stable@vger.kernel.org
Signed-off-by: Thomas Fourier <fourier.thomas@gmail.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: Thomas-fourier

drivers/mtd/nand/raw/renesas-nand-controller.c

@@ -426,6 +426,9 @@ static int rnandc_read_page_hw_ecc(struct nand_chip *chip, u8 *buf,
 	/* Configure DMA */
 	dma_addr = dma_map_single(rnandc->dev, rnandc->buf, mtd->writesize,
 				  DMA_FROM_DEVICE);
+	if (dma_mapping_error(rnandc->dev, dma_addr))
+		return -ENOMEM;
+
 	writel(dma_addr, rnandc->regs + DMA_ADDR_LOW_REG);
 	writel(mtd->writesize, rnandc->regs + DMA_CNT_REG);
 	writel(DMA_TLVL_MAX, rnandc->regs + DMA_TLVL_REG);
@@ -606,6 +609,9 @@ static int rnandc_write_page_hw_ecc(struct nand_chip *chip, const u8 *buf,
 	/* Configure DMA */
 	dma_addr = dma_map_single(rnandc->dev, (void *)rnandc->buf, mtd->writesize,
 				  DMA_TO_DEVICE);
+	if (dma_mapping_error(rnandc->dev, dma_addr))
+		return -ENOMEM;
+
 	writel(dma_addr, rnandc->regs + DMA_ADDR_LOW_REG);
 	writel(mtd->writesize, rnandc->regs + DMA_CNT_REG);
 	writel(DMA_TLVL_MAX, rnandc->regs + DMA_TLVL_REG);