bnx2: Fix bug in bnx2_free_tx_skbs().

[ Upstream commit c1f5163de417dab01fa9daaf09a74bbb19303f3c ]

In rare cases, bnx2x_free_tx_skbs() can unmap the wrong DMA address
when it gets to the last entry of the tx ring.  We were not using
the proper macro to skip the last entry when advancing the tx index.

Reported-by: Zongyun Lai <zlai@vmware.com>
Reviewed-by: Jeffrey Huang <huangjw@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/drivers/net/ethernet/broadcom/bnx2.c b/drivers/net/ethernet/broadcom/bnx2.c
index 965c7235804d61aa4c493b472239a29bde66bcb7..721adfd086084908b5caa0b3a60f0ff6fc4eb3b5 100644 (file)
--- a/drivers/net/ethernet/broadcom/bnx2.c
+++ b/drivers/net/ethernet/broadcom/bnx2.c
@@ -5378,7 +5378,7 @@ bnx2_free_tx_skbs(struct bnx2 *bp)
                        int k, last;
 
                        if (skb == NULL) {
-                               j++;
+                               j = NEXT_TX_BD(j);
                                continue;
                        }
 
@@ -5390,8 +5390,8 @@ bnx2_free_tx_skbs(struct bnx2 *bp)
                        tx_buf->skb = NULL;
 
                        last = tx_buf->nr_frags;
-                       j++;
-                       for (k = 0; k < last; k++, j++) {
+                       j = NEXT_TX_BD(j);
+                       for (k = 0; k < last; k++, j = NEXT_TX_BD(j)) {
                                tx_buf = &txr->tx_buf_ring[TX_RING_IDX(j)];
                                dma_unmap_page(&bp->pdev->dev,
                                        dma_unmap_addr(tx_buf, mapping),