r8152: add skb_cow_head

Call skb_cow_head() before editing the tx packet header. The header
would be reallocated if it is shared.

Signed-off-by: Hayes Wang <hayeswang@realtek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/usb/r8152.c b/drivers/net/usb/r8152.c
index c7ef30dee1b9cf68ab9da7633660a6a98647216a..a90a7eb91f1ccd83829c6e3af204c552e0b42f37 100644 (file)
--- a/drivers/net/usb/r8152.c
+++ b/drivers/net/usb/r8152.c
@@ -1376,6 +1376,11 @@ static int msdn_giant_send_check(struct sk_buff *skb)
 {
        const struct ipv6hdr *ipv6h;
        struct tcphdr *th;
+       int ret;
+
+       ret = skb_cow_head(skb, 0);
+       if (ret)
+               return ret;
 
        ipv6h = ipv6_hdr(skb);
        th = tcp_hdr(skb);
@@ -1383,7 +1388,7 @@ static int msdn_giant_send_check(struct sk_buff *skb)
        th->check = 0;
        th->check = ~tcp_v6_check(0, &ipv6h->saddr, &ipv6h->daddr, 0);
 
-       return 0;
+       return ret;
 }
 
 static int r8152_tx_csum(struct r8152 *tp, struct tx_desc *desc,
@@ -1412,8 +1417,11 @@ static int r8152_tx_csum(struct r8152 *tp, struct tx_desc *desc,
                        break;
 
                case htons(ETH_P_IPV6):
+                       if (msdn_giant_send_check(skb)) {
+                               ret = TX_CSUM_TSO;
+                               goto unavailable;
+                       }
                        opts1 |= GTSENDV6;
-                       msdn_giant_send_check(skb);
                        break;
 
                default: