3c515: Write outside array bounds

if dev_alloc_skb() fails on the first iteration, a write to
cp->rx_ring[-1] occurs.

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/3c515.c b/drivers/net/3c515.c
index 3e00fa8ea65f106544c7a5f67a4c6535d499c690..4a7c32895be52fecbd2ce7ae87d75b639b4dc15a 100644 (file)
--- a/drivers/net/3c515.c
+++ b/drivers/net/3c515.c
@@ -832,7 +832,9 @@ static int corkscrew_open(struct net_device *dev)
                        skb_reserve(skb, 2);    /* Align IP on 16 byte boundaries */
                        vp->rx_ring[i].addr = isa_virt_to_bus(skb->data);
                }
-               vp->rx_ring[i - 1].next = isa_virt_to_bus(&vp->rx_ring[0]);     /* Wrap the ring. */
+               if (i != 0)
+                       vp->rx_ring[i - 1].next =
+                               isa_virt_to_bus(&vp->rx_ring[0]);       /* Wrap the ring. */
                outl(isa_virt_to_bus(&vp->rx_ring[0]), ioaddr + UpListPtr);
        }
        if (vp->full_bus_master_tx) {   /* Boomerang bus master Tx. */