vmxnet3: fix checks for dma mapping errors

vmxnet3_drv does not check dma_addr with dma_mapping_error()
after mapping dma memory. The patch adds the checks and
tries to handle failures.

Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Acked-by: Shrikrishna Khare <skhare@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/vmxnet3/vmxnet3_drv.c

@@ -587,6 +587,12 @@ vmxnet3_rq_alloc_rx_buf(struct vmxnet3_rx_queue *rq, u32 ring_idx,
 						&adapter->pdev->dev,
 						rbi->skb->data, rbi->len,
 						PCI_DMA_FROMDEVICE);
+				if (dma_mapping_error(&adapter->pdev->dev,
+						      rbi->dma_addr)) {
+					dev_kfree_skb_any(rbi->skb);
+					rq->stats.rx_buf_alloc_failure++;
+					break;
+				}
 			} else {
 				/* rx buffer skipped by the device */
 			}
@@ -605,13 +611,18 @@ vmxnet3_rq_alloc_rx_buf(struct vmxnet3_rx_queue *rq, u32 ring_idx,
 						&adapter->pdev->dev,
 						rbi->page, 0, PAGE_SIZE,
 						PCI_DMA_FROMDEVICE);
+				if (dma_mapping_error(&adapter->pdev->dev,
+						      rbi->dma_addr)) {
+					put_page(rbi->page);
+					rq->stats.rx_buf_alloc_failure++;
+					break;
+				}
 			} else {
 				/* rx buffers skipped by the device */
 			}
 			val = VMXNET3_RXD_BTYPE_BODY << VMXNET3_RXD_BTYPE_SHIFT;
 		}
 
-		BUG_ON(rbi->dma_addr == 0);
 		gd->rxd.addr = cpu_to_le64(rbi->dma_addr);
 		gd->dword[2] = cpu_to_le32((!ring->gen << VMXNET3_RXD_GEN_SHIFT)
 					   | val | rbi->len);
@@ -655,7 +666,7 @@ vmxnet3_append_frag(struct sk_buff *skb, struct Vmxnet3_RxCompDesc *rcd,
 }
 
 
-static void
+static int
 vmxnet3_map_pkt(struct sk_buff *skb, struct vmxnet3_tx_ctx *ctx,
 		struct vmxnet3_tx_queue *tq, struct pci_dev *pdev,
 		struct vmxnet3_adapter *adapter)
@@ -715,6 +726,8 @@ vmxnet3_map_pkt(struct sk_buff *skb, struct vmxnet3_tx_ctx *ctx,
 		tbi->dma_addr = dma_map_single(&adapter->pdev->dev,
 				skb->data + buf_offset, buf_size,
 				PCI_DMA_TODEVICE);
+		if (dma_mapping_error(&adapter->pdev->dev, tbi->dma_addr))
+			return -EFAULT;
 
 		tbi->len = buf_size;
 
@@ -755,6 +768,8 @@ vmxnet3_map_pkt(struct sk_buff *skb, struct vmxnet3_tx_ctx *ctx,
 			tbi->dma_addr = skb_frag_dma_map(&adapter->pdev->dev, frag,
 							 buf_offset, buf_size,
 							 DMA_TO_DEVICE);
+			if (dma_mapping_error(&adapter->pdev->dev, tbi->dma_addr))
+				return -EFAULT;
 
 			tbi->len = buf_size;
 
@@ -782,6 +797,8 @@ vmxnet3_map_pkt(struct sk_buff *skb, struct vmxnet3_tx_ctx *ctx,
 	/* set the last buf_info for the pkt */
 	tbi->skb = skb;
 	tbi->sop_idx = ctx->sop_txd - tq->tx_ring.base;
+
+	return 0;
 }
 
 
@@ -1020,7 +1037,8 @@ vmxnet3_tq_xmit(struct sk_buff *skb, struct vmxnet3_tx_queue *tq,
 	}
 
 	/* fill tx descs related to addr & len */
-	vmxnet3_map_pkt(skb, &ctx, tq, adapter->pdev, adapter);
+	if (vmxnet3_map_pkt(skb, &ctx, tq, adapter->pdev, adapter))
+		goto unlock_drop_pkt;
 
 	/* setup the EOP desc */
 	ctx.eop_txd->dword[3] = cpu_to_le32(VMXNET3_TXD_CQ | VMXNET3_TXD_EOP);
@@ -1231,6 +1249,7 @@ vmxnet3_rq_rx_complete(struct vmxnet3_rx_queue *rq,
 		struct vmxnet3_rx_buf_info *rbi;
 		struct sk_buff *skb, *new_skb = NULL;
 		struct page *new_page = NULL;
+		dma_addr_t new_dma_addr;
 		int num_to_alloc;
 		struct Vmxnet3_RxDesc *rxd;
 		u32 idx, ring_idx;
@@ -1287,6 +1306,21 @@ vmxnet3_rq_rx_complete(struct vmxnet3_rx_queue *rq,
 				skip_page_frags = true;
 				goto rcd_done;
 			}
+			new_dma_addr = dma_map_single(&adapter->pdev->dev,
+						      new_skb->data, rbi->len,
+						      PCI_DMA_FROMDEVICE);
+			if (dma_mapping_error(&adapter->pdev->dev,
+					      new_dma_addr)) {
+				dev_kfree_skb(new_skb);
+				/* Skb allocation failed, do not handover this
+				 * skb to stack. Reuse it. Drop the existing pkt
+				 */
+				rq->stats.rx_buf_alloc_failure++;
+				ctx->skb = NULL;
+				rq->stats.drop_total++;
+				skip_page_frags = true;
+				goto rcd_done;
+			}
 
 			dma_unmap_single(&adapter->pdev->dev, rbi->dma_addr,
 					 rbi->len,
@@ -1303,9 +1337,7 @@ vmxnet3_rq_rx_complete(struct vmxnet3_rx_queue *rq,
 
 			/* Immediate refill */
 			rbi->skb = new_skb;
-			rbi->dma_addr = dma_map_single(&adapter->pdev->dev,
-						       rbi->skb->data, rbi->len,
-						       PCI_DMA_FROMDEVICE);
+			rbi->dma_addr = new_dma_addr;
 			rxd->addr = cpu_to_le64(rbi->dma_addr);
 			rxd->len = rbi->len;
 			if (adapter->version == 2 &&
@@ -1348,6 +1380,19 @@ vmxnet3_rq_rx_complete(struct vmxnet3_rx_queue *rq,
 					skip_page_frags = true;
 					goto rcd_done;
 				}
+				new_dma_addr = dma_map_page(&adapter->pdev->dev
+							, rbi->page,
+							0, PAGE_SIZE,
+							PCI_DMA_FROMDEVICE);
+				if (dma_mapping_error(&adapter->pdev->dev,
+						      new_dma_addr)) {
+					put_page(new_page);
+					rq->stats.rx_buf_alloc_failure++;
+					dev_kfree_skb(ctx->skb);
+					ctx->skb = NULL;
+					skip_page_frags = true;
+					goto rcd_done;
+				}
 
 				dma_unmap_page(&adapter->pdev->dev,
 					       rbi->dma_addr, rbi->len,
@@ -1357,10 +1402,7 @@ vmxnet3_rq_rx_complete(struct vmxnet3_rx_queue *rq,
 
 				/* Immediate refill */
 				rbi->page = new_page;
-				rbi->dma_addr = dma_map_page(&adapter->pdev->dev
-							, rbi->page,
-							0, PAGE_SIZE,
-							PCI_DMA_FROMDEVICE);
+				rbi->dma_addr = new_dma_addr;
 				rxd->addr = cpu_to_le64(rbi->dma_addr);
 				rxd->len = rbi->len;
 			}
@@ -2167,7 +2209,8 @@ vmxnet3_set_mc(struct net_device *netdev)
 							PCI_DMA_TODEVICE);
 			}
 
-			if (new_table_pa) {
+			if (!dma_mapping_error(&adapter->pdev->dev,
+					       new_table_pa)) {
 				new_mode |= VMXNET3_RXM_MCAST;
 				rxConf->mfTablePA = cpu_to_le64(new_table_pa);
 			} else {
@@ -3075,6 +3118,11 @@ vmxnet3_probe_device(struct pci_dev *pdev,
 	adapter->adapter_pa = dma_map_single(&adapter->pdev->dev, adapter,
 					     sizeof(struct vmxnet3_adapter),
 					     PCI_DMA_TODEVICE);
+	if (dma_mapping_error(&adapter->pdev->dev, adapter->adapter_pa)) {
+		dev_err(&pdev->dev, "Failed to map dma\n");
+		err = -EFAULT;
+		goto err_dma_map;
+	}
 	adapter->shared = dma_alloc_coherent(
 				&adapter->pdev->dev,
 				sizeof(struct Vmxnet3_DriverShared),
@@ -3233,6 +3281,7 @@ vmxnet3_probe_device(struct pci_dev *pdev,
 err_alloc_shared:
 	dma_unmap_single(&adapter->pdev->dev, adapter->adapter_pa,
 			 sizeof(struct vmxnet3_adapter), PCI_DMA_TODEVICE);
+err_dma_map:
 	free_netdev(netdev);
 	return err;
 }