mmc: wbsd: implement check for dma mapping error

wbsd_request_dma() does not check for dma mapping errors.

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/wbsd.c b/drivers/mmc/host/wbsd.c
index c3fd16d997caba4d903d6e8d3ea35acd0f350075..80a3b11f3217143bee5e15fdb24f2f1c346a1105 100644 (file)
--- a/drivers/mmc/host/wbsd.c
+++ b/drivers/mmc/host/wbsd.c
@@ -1395,23 +1395,25 @@ static void wbsd_request_dma(struct wbsd_host *host, int dma)
         */
        host->dma_addr = dma_map_single(mmc_dev(host->mmc), host->dma_buffer,
                WBSD_DMA_SIZE, DMA_BIDIRECTIONAL);
+       if (dma_mapping_error(mmc_dev(host->mmc), host->dma_addr))
+               goto kfree;
 
        /*
         * ISA DMA must be aligned on a 64k basis.
         */
        if ((host->dma_addr & 0xffff) != 0)
-               goto kfree;
+               goto unmap;
        /*
         * ISA cannot access memory above 16 MB.
         */
        else if (host->dma_addr >= 0x1000000)
-               goto kfree;
+               goto unmap;
 
        host->dma = dma;
 
        return;
 
-kfree:
+unmap:
        /*
         * If we've gotten here then there is some kind of alignment bug
         */
@@ -1421,6 +1423,7 @@ kfree:
                WBSD_DMA_SIZE, DMA_BIDIRECTIONAL);
        host->dma_addr = 0;
 
+kfree:
        kfree(host->dma_buffer);
        host->dma_buffer = NULL;
 
@@ -1434,7 +1437,7 @@ err:
 
 static void wbsd_release_dma(struct wbsd_host *host)
 {
-       if (host->dma_addr) {
+       if (!dma_mapping_error(mmc_dev(host->mmc), host->dma_addr)) {
                dma_unmap_single(mmc_dev(host->mmc), host->dma_addr,
                        WBSD_DMA_SIZE, DMA_BIDIRECTIONAL);
        }