ipv6: avoid a dst_entry refcount change in ipv6_destopt_rcv()

ipv6_destopt_rcv() runs with rcu_read_lock(), so there is no need to
take a temporay reference on dst_entry, even if skb is freed by
ip6_parse_tlv()

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2011-07-28 04:00:35 +00:00 committed by David S. Miller
parent d14730b8e9
commit 897dc80b95

View File

@ -273,12 +273,12 @@ static int ipv6_destopt_rcv(struct sk_buff *skb)
#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
__u16 dstbuf;
#endif
struct dst_entry *dst;
struct dst_entry *dst = skb_dst(skb);
if (!pskb_may_pull(skb, skb_transport_offset(skb) + 8) ||
!pskb_may_pull(skb, (skb_transport_offset(skb) +
((skb_transport_header(skb)[1] + 1) << 3)))) {
IP6_INC_STATS_BH(dev_net(skb_dst(skb)->dev), ip6_dst_idev(skb_dst(skb)),
IP6_INC_STATS_BH(dev_net(dst->dev), ip6_dst_idev(dst),
IPSTATS_MIB_INHDRERRORS);
kfree_skb(skb);
return -1;
@ -289,9 +289,7 @@ static int ipv6_destopt_rcv(struct sk_buff *skb)
dstbuf = opt->dst1;
#endif
dst = dst_clone(skb_dst(skb));
if (ip6_parse_tlv(tlvprocdestopt_lst, skb)) {
dst_release(dst);
skb->transport_header += (skb_transport_header(skb)[1] + 1) << 3;
opt = IP6CB(skb);
#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
@ -304,7 +302,6 @@ static int ipv6_destopt_rcv(struct sk_buff *skb)
IP6_INC_STATS_BH(dev_net(dst->dev),
ip6_dst_idev(dst), IPSTATS_MIB_INHDRERRORS);
dst_release(dst);
return -1;
}