sundance: Fix oopses with corrupted skb_shared_info

Joel Soete reported oopses at the beginning of pppoe connections since
v2.6.35. After debugging the bug was found in sundance skb allocation
and dma mapping code, where skb_reserve() bytes aren't taken into
account. This is an old bug, only uncovered by some change in 2.6.35.

Initial debugging patch by: Eric Dumazet <eric.dumazet@gmail.com>

Reported-by: Joel Soete <soete.joel@scarlet.be>
Tested-by: Joel Soete <soete.joel@scarlet.be>
Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/sundance.c b/drivers/net/sundance.c
index 3ed2a67bd6d36c5da4608570bc8d494faa614f59..b409d7ec4ac15ff5e5eb82c2aff17111d48954a3 100644 (file)
--- a/drivers/net/sundance.c
+++ b/drivers/net/sundance.c
@@ -1016,7 +1016,7 @@ static void init_ring(struct net_device *dev)
 
        /* Fill in the Rx buffers.  Handle allocation failure gracefully. */
        for (i = 0; i < RX_RING_SIZE; i++) {
-               struct sk_buff *skb = dev_alloc_skb(np->rx_buf_sz);
+               struct sk_buff *skb = dev_alloc_skb(np->rx_buf_sz + 2);
                np->rx_skbuff[i] = skb;
                if (skb == NULL)
                        break;
@@ -1407,7 +1407,7 @@ static void refill_rx (struct net_device *dev)
                struct sk_buff *skb;
                entry = np->dirty_rx % RX_RING_SIZE;
                if (np->rx_skbuff[entry] == NULL) {
-                       skb = dev_alloc_skb(np->rx_buf_sz);
+                       skb = dev_alloc_skb(np->rx_buf_sz + 2);
                        np->rx_skbuff[entry] = skb;
                        if (skb == NULL)
                                break;          /* Better luck next round. */