[PATCH] e1000e: use ip_hdrlen() instead of bit shift

[Moon Yeounsu]

There's no reason to use bit shift to find the UDP header.
It's not intuitive and it reinvents well-defined functions.

Signed-off-by: Moon Yeounsu <yyyynoom@xxxxxxxxx>
---
 drivers/net/ethernet/intel/e1000e/netdev.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c
index 360ee26557f7..07c4cf84bdf3 100644
--- a/drivers/net/ethernet/intel/e1000e/netdev.c
+++ b/drivers/net/ethernet/intel/e1000e/netdev.c
@@ -5731,7 +5731,7 @@ static int e1000_transfer_dhcp_info(struct e1000_adapter *adapter,
 		if (ip->protocol != IPPROTO_UDP)
 			return 0;
 
-		udp = (struct udphdr *)((u8 *)ip + (ip->ihl << 2));
+		udp = (struct udphdr *)((u8 *)ip + ip_hdrlen(skb));
 		if (ntohs(udp->dest) != 67)
 			return 0;
 
-- 
2.45.2