[BNX2]: Fix UDP checksum verification

Fix TCP/UDP checksum verification. Use status bits in the buffer
descriptor instead of the checksum value to verify rx checksum.
Using the checksum value will be incorrect if the UDP packet has
zero in the UDP checksum field.

Firmware update required for this fix.

Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/bnx2.c

@@ -1660,7 +1660,7 @@ bnx2_rx_int(struct bnx2 *bp, int budget)
 	rmb();
 	while (sw_cons != hw_cons) {
 		unsigned int len;
-		u16 status;
+		u32 status;
 		struct sw_bd *rx_buf;
 		struct sk_buff *skb;
 
@@ -1676,7 +1676,7 @@ bnx2_rx_int(struct bnx2 *bp, int budget)
 		rx_hdr = (struct l2_fhdr *) skb->data;
 		len = rx_hdr->l2_fhdr_pkt_len - 4;
 
-		if (rx_hdr->l2_fhdr_errors &
+		if ((status = rx_hdr->l2_fhdr_status) &
 			(L2_FHDR_ERRORS_BAD_CRC |
 			L2_FHDR_ERRORS_PHY_DECODE |
 			L2_FHDR_ERRORS_ALIGNMENT |
@@ -1735,15 +1735,13 @@ bnx2_rx_int(struct bnx2 *bp, int budget)
 
 		}
 
-		status = rx_hdr->l2_fhdr_status;
 		skb->ip_summed = CHECKSUM_NONE;
 		if (bp->rx_csum &&
 			(status & (L2_FHDR_STATUS_TCP_SEGMENT |
 			L2_FHDR_STATUS_UDP_DATAGRAM))) {
 
-			u16 cksum = rx_hdr->l2_fhdr_tcp_udp_xsum;
-
-			if (cksum == 0xffff)
+			if (likely((status & (L2_FHDR_ERRORS_TCP_XSUM |
+					      L2_FHDR_ERRORS_UDP_XSUM)) == 0))
 				skb->ip_summed = CHECKSUM_UNNECESSARY;
 		}
 
@@ -3978,7 +3976,7 @@ bnx2_test_loopback(struct bnx2 *bp)
 		pci_unmap_addr(rx_buf, mapping),
 		bp->rx_buf_size, PCI_DMA_FROMDEVICE);
 
-	if (rx_hdr->l2_fhdr_errors &
+	if (rx_hdr->l2_fhdr_status &
 		(L2_FHDR_ERRORS_BAD_CRC |
 		L2_FHDR_ERRORS_PHY_DECODE |
 		L2_FHDR_ERRORS_ALIGNMENT |

drivers/net/bnx2.h

@@ -277,19 +277,7 @@ struct statistics_block {
  *  l2_fhdr definition
  */
 struct l2_fhdr {
-#if defined(__BIG_ENDIAN)
-	u16 l2_fhdr_errors;
-	u16 l2_fhdr_status;
-#elif defined(__LITTLE_ENDIAN)
-	u16 l2_fhdr_status;
-	u16 l2_fhdr_errors;
-#endif
-		#define L2_FHDR_ERRORS_BAD_CRC		(1<<1)
-		#define L2_FHDR_ERRORS_PHY_DECODE	(1<<2)
-		#define L2_FHDR_ERRORS_ALIGNMENT	(1<<3)
-		#define L2_FHDR_ERRORS_TOO_SHORT	(1<<4)
-		#define L2_FHDR_ERRORS_GIANT_FRAME	(1<<5)
-
+	u32 l2_fhdr_status;
 		#define L2_FHDR_STATUS_RULE_CLASS	(0x7<<0)
 		#define L2_FHDR_STATUS_RULE_P2		(1<<3)
 		#define L2_FHDR_STATUS_RULE_P3		(1<<4)
@@ -301,6 +289,14 @@ struct l2_fhdr {
 		#define L2_FHDR_STATUS_TCP_SEGMENT	(1<<14)
 		#define L2_FHDR_STATUS_UDP_DATAGRAM	(1<<15)
 
+		#define L2_FHDR_ERRORS_BAD_CRC		(1<<17)
+		#define L2_FHDR_ERRORS_PHY_DECODE	(1<<18)
+		#define L2_FHDR_ERRORS_ALIGNMENT	(1<<19)
+		#define L2_FHDR_ERRORS_TOO_SHORT	(1<<20)
+		#define L2_FHDR_ERRORS_GIANT_FRAME	(1<<21)
+		#define L2_FHDR_ERRORS_TCP_XSUM		(1<<28)
+		#define L2_FHDR_ERRORS_UDP_XSUM		(1<<31)
+
 	u32 l2_fhdr_hash;
 #if defined(__BIG_ENDIAN)
 	u16 l2_fhdr_pkt_len;