mmc: mmc_spi: add checks for dma mapping error

There is no checks for dma mapping errors in mmc_spi.
Tha patch fixes that and by the way it adds dma_unmap_single(ones_dma)
that was left on a failure path mmc_spi_probe().

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

diff --git a/drivers/mmc/host/mmc_spi.c b/drivers/mmc/host/mmc_spi.c
index 1c1b45e..3446097 100644 (file)
--- a/drivers/mmc/host/mmc_spi.c
+++ b/drivers/mmc/host/mmc_spi.c
@@ -925,6 +925,10 @@ mmc_spi_data_do(struct mmc_spi_host *host, struct mmc_command *cmd,
 
                        dma_addr = dma_map_page(dma_dev, sg_page(sg), 0,
                                                PAGE_SIZE, dir);
+                       if (dma_mapping_error(dma_dev, dma_addr)) {
+                               data->error = -EFAULT;
+                               break;
+                       }
                        if (direction == DMA_TO_DEVICE)
                                t->tx_dma = dma_addr + sg->offset;
                        else
@@ -1393,10 +1397,12 @@ static int mmc_spi_probe(struct spi_device *spi)
                host->dma_dev = dev;
                host->ones_dma = dma_map_single(dev, ones,
                                MMC_SPI_BLOCKSIZE, DMA_TO_DEVICE);
+               if (dma_mapping_error(dev, host->ones_dma))
+                       goto fail_ones_dma;
                host->data_dma = dma_map_single(dev, host->data,
                                sizeof(*host->data), DMA_BIDIRECTIONAL);
-
-               /* REVISIT in theory those map operations can fail... */
+               if (dma_mapping_error(dev, host->data_dma))
+                       goto fail_data_dma;
 
                dma_sync_single_for_cpu(host->dma_dev,
                                host->data_dma, sizeof(*host->data),
@@ -1462,6 +1468,11 @@ fail_glue_init:
        if (host->dma_dev)
                dma_unmap_single(host->dma_dev, host->data_dma,
                                sizeof(*host->data), DMA_BIDIRECTIONAL);
+fail_data_dma:
+       if (host->dma_dev)
+               dma_unmap_single(host->dma_dev, host->ones_dma,
+                               MMC_SPI_BLOCKSIZE, DMA_TO_DEVICE);
+fail_ones_dma:
        kfree(host->data);
 
 fail_nobuf1: