vmxnet3: avoid assumption about invalid dma_pa in vmxnet3_set_mc()

vmxnet3_set_mc() checks new_table_pa returned by dma_map_single()
with dma_mapping_error(), but even there it assumes zero is invalid pa
(it assumes dma_mapping_error(...,0) returns true if new_table is NULL).

The patch adds an explicit variable to track status of new_table_pa.

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

v2: use "bool" and "true"/"false" for boolean variables.
Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/vmxnet3/vmxnet3_drv.c b/drivers/net/vmxnet3/vmxnet3_drv.c
index b5554f2..ef83ae3 100644 (file)
--- a/drivers/net/vmxnet3/vmxnet3_drv.c
+++ b/drivers/net/vmxnet3/vmxnet3_drv.c
@@ -2279,6 +2279,7 @@ vmxnet3_set_mc(struct net_device *netdev)
                                        &adapter->shared->devRead.rxFilterConf;
        u8 *new_table = NULL;
        dma_addr_t new_table_pa = 0;
+       bool new_table_pa_valid = false;
        u32 new_mode = VMXNET3_RXM_UCAST;
 
        if (netdev->flags & IFF_PROMISC) {
@@ -2307,13 +2308,15 @@ vmxnet3_set_mc(struct net_device *netdev)
                                                        new_table,
                                                        sz,
                                                        PCI_DMA_TODEVICE);
+                               if (!dma_mapping_error(&adapter->pdev->dev,
+                                                      new_table_pa)) {
+                                       new_mode |= VMXNET3_RXM_MCAST;
+                                       new_table_pa_valid = true;
+                                       rxConf->mfTablePA = cpu_to_le64(
+                                                               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 {
+                       if (!new_table_pa_valid) {
                                netdev_info(netdev,
                                            "failed to copy mcast list, setting ALL_MULTI\n");
                                new_mode |= VMXNET3_RXM_ALL_MULTI;
@@ -2338,7 +2341,7 @@ vmxnet3_set_mc(struct net_device *netdev)
                               VMXNET3_CMD_UPDATE_MAC_FILTERS);
        spin_unlock_irqrestore(&adapter->cmd_lock, flags);
 
-       if (new_table_pa)
+       if (new_table_pa_valid)
                dma_unmap_single(&adapter->pdev->dev, new_table_pa,
                                 rxConf->mfTableLen, PCI_DMA_TODEVICE);
        kfree(new_table);