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

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

Fixes: 058e0e8 ("mtd: rawnand: rockchip: NFC driver for RK3308, RK2928 and others")
Signed-off-by: Thomas Fourier <fourier.thomas@gmail.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Author: Thomas-fourier

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

@@ -656,9 +656,16 @@ static int rk_nfc_write_page_hwecc(struct nand_chip *chip, const u8 *buf,
 
 	dma_data = dma_map_single(nfc->dev, (void *)nfc->page_buf,
 				  mtd->writesize, DMA_TO_DEVICE);
+	if (dma_mapping_error(nfc->dev, dma_data))
+		return -ENOMEM;
+
 	dma_oob = dma_map_single(nfc->dev, nfc->oob_buf,
 				 ecc->steps * oob_step,
 				 DMA_TO_DEVICE);
+	if (dma_mapping_error(nfc->dev, dma_oob)) {
+		dma_unmap_single(nfc->dev, dma_data, mtd->writesize, DMA_TO_DEVICE);
+		return -ENOMEM;
+	}
 
 	reinit_completion(&nfc->done);
 	writel(INT_DMA, nfc->regs + nfc->cfg->int_en_off);
@@ -772,9 +779,17 @@ static int rk_nfc_read_page_hwecc(struct nand_chip *chip, u8 *buf, int oob_on,
 	dma_data = dma_map_single(nfc->dev, nfc->page_buf,
 				  mtd->writesize,
 				  DMA_FROM_DEVICE);
+	if (dma_mapping_error(nfc->dev, dma_data))
+		return -ENOMEM;
+
 	dma_oob = dma_map_single(nfc->dev, nfc->oob_buf,
 				 ecc->steps * oob_step,
 				 DMA_FROM_DEVICE);
+	if (dma_mapping_error(nfc->dev, dma_oob)) {
+		dma_unmap_single(nfc->dev, dma_data, mtd->writesize,
+				 DMA_FROM_DEVICE);
+		return -ENOMEM;
+	}
 
 	/*
 	 * The first blocks (4, 8 or 16 depending on the device)