niu: Fix to check for dma mapping errors.

Fix Neptune ethernet driver to check dma mapping error after map_page()
interface returns.

Signed-off-by: Shuah Khan <shuah.khan@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 4 insertions, 0 deletions

diff --git a/drivers/net/ethernet/sun/niu.c b/drivers/net/ethernet/sun/niu.c
index 8c726b7004d3..60d5c035d946 100644
--- a/drivers/net/ethernet/sun/niu.c
+++ b/drivers/net/ethernet/sun/niu.c
@@ -3335,6 +3335,10 @@ static int niu_rbr_add_page(struct niu *np, struct rx_ring_info *rp,
 
         addr = np->ops->map_page(np->device, page, 0,
                                  PAGE_SIZE, DMA_FROM_DEVICE);
+        if (!addr) {
+                __free_page(page);
+                return -ENOMEM;
+        }
 
         niu_hash_page(rp, page, addr);
         if (rp->rbr_blocks_per_page > 1)