epic100: hamachi: yellowfin: Fix skb allocation size

Joel Soete reported oopses during pppoe over sundance NIC, caused by
a bug in skb allocation and dma mapping code, where skb_reserve()
bytes weren't taken into account. As a followup to the patch:
"sundance: Fix oopses with corrupted skb_shared_info" very similar
code is fixed here for three other drivers.

Signed-off-by: Jarek Poplawski <[e-mail]>
Cc: Joel Soete <[e-mail]>
Cc: Eric Dumazet <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

drivers/net/epic100.c

···
 
 	/* Fill in the Rx buffers.  Handle allocation failure gracefully. */
 	for (i = 0; i < RX_RING_SIZE; i++) {
-		struct sk_buff *skb = dev_alloc_skb(ep->rx_buf_sz);
+		struct sk_buff *skb = dev_alloc_skb(ep->rx_buf_sz + 2);
 		ep->rx_skbuff[i] = skb;
 		if (skb == NULL)
 			break;
···
 		entry = ep->dirty_rx % RX_RING_SIZE;
 		if (ep->rx_skbuff[entry] == NULL) {
 			struct sk_buff *skb;
-			skb = ep->rx_skbuff[entry] = dev_alloc_skb(ep->rx_buf_sz);
+			skb = ep->rx_skbuff[entry] = dev_alloc_skb(ep->rx_buf_sz + 2);
 			if (skb == NULL)
 				break;
 			skb_reserve(skb, 2);	/* Align IP on 16 byte boundaries */

drivers/net/hamachi.c

···
 	}
 	/* Fill in the Rx buffers.  Handle allocation failure gracefully. */
 	for (i = 0; i < RX_RING_SIZE; i++) {
-		struct sk_buff *skb = dev_alloc_skb(hmp->rx_buf_sz);
+		struct sk_buff *skb = dev_alloc_skb(hmp->rx_buf_sz + 2);
 		hmp->rx_skbuff[i] = skb;
 		if (skb == NULL)
 			break;
···
 		entry = hmp->dirty_rx % RX_RING_SIZE;
 		desc = &(hmp->rx_ring[entry]);
 		if (hmp->rx_skbuff[entry] == NULL) {
-			struct sk_buff *skb = dev_alloc_skb(hmp->rx_buf_sz);
+			struct sk_buff *skb = dev_alloc_skb(hmp->rx_buf_sz + 2);
 
 			hmp->rx_skbuff[entry] = skb;
 			if (skb == NULL)

drivers/net/yellowfin.c

···
 	}
 
 	for (i = 0; i < RX_RING_SIZE; i++) {
-		struct sk_buff *skb = dev_alloc_skb(yp->rx_buf_sz);
+		struct sk_buff *skb = dev_alloc_skb(yp->rx_buf_sz + 2);
 		yp->rx_skbuff[i] = skb;
 		if (skb == NULL)
 			break;
···
 	for (; yp->cur_rx - yp->dirty_rx > 0; yp->dirty_rx++) {
 		entry = yp->dirty_rx % RX_RING_SIZE;
 		if (yp->rx_skbuff[entry] == NULL) {
-			struct sk_buff *skb = dev_alloc_skb(yp->rx_buf_sz);
+			struct sk_buff *skb = dev_alloc_skb(yp->rx_buf_sz + 2);
 			if (skb == NULL)
 				break;				/* Better luck next round. */
 			yp->rx_skbuff[entry] = skb;