From bba98083499f63f62419edf42022275d34a72470 Mon Sep 17 00:00:00 2001 From: Menglong Dong Date: Wed, 13 Apr 2022 16:15:57 +0800 Subject: [PATCH] net: ipv6: remove redundant statistics in ipv6_hop_jumbo() There are two call chains for ipv6_hop_jumbo(). The first one is: ipv6_destopt_rcv() -> ip6_parse_tlv() -> ipv6_hop_jumbo() On this call chain, the drop statistics will be done in ipv6_destopt_rcv() with 'IPSTATS_MIB_INHDRERRORS' if ipv6_hop_jumbo() returns false. The second call chain is: ip6_rcv_core() -> ipv6_parse_hopopts() -> ip6_parse_tlv() And the drop statistics will also be done in ip6_rcv_core() with 'IPSTATS_MIB_INHDRERRORS' if ipv6_hop_jumbo() returns false. Therefore, the statistics in ipv6_hop_jumbo() is redundant, which means the drop is counted twice. The statistics in ipv6_hop_jumbo() is almost the same as the outside, except the 'IPSTATS_MIB_INTRUNCATEDPKTS', which seems that we have to ignore it. Signed-off-by: Menglong Dong Reviewed-by: Jiang Biao Reviewed-by: Hao Peng Signed-off-by: David S. Miller --- net/ipv6/exthdrs.c | 9 +-------- 1 file changed, 1 insertion(+), 8 deletions(-) diff --git a/net/ipv6/exthdrs.c b/net/ipv6/exthdrs.c index a2094aa1cb32..403f8ba76b9f 100644 --- a/net/ipv6/exthdrs.c +++ b/net/ipv6/exthdrs.c @@ -994,33 +994,26 @@ drop: static bool ipv6_hop_jumbo(struct sk_buff *skb, int optoff) { const unsigned char *nh = skb_network_header(skb); - struct inet6_dev *idev = __in6_dev_get_safely(skb->dev); - struct net *net = ipv6_skb_net(skb); u32 pkt_len; if (nh[optoff + 1] != 4 || (optoff & 3) != 2) { net_dbg_ratelimited("ipv6_hop_jumbo: wrong jumbo opt length/alignment %d\n", nh[optoff+1]); - __IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS); goto drop; } pkt_len = ntohl(*(__be32 *)(nh + optoff + 2)); if (pkt_len <= IPV6_MAXPLEN) { - __IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS); icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff+2); return false; } if (ipv6_hdr(skb)->payload_len) { - __IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS); icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff); return false; } - if (pkt_len > skb->len - sizeof(struct ipv6hdr)) { - __IP6_INC_STATS(net, idev, IPSTATS_MIB_INTRUNCATEDPKTS); + if (pkt_len > skb->len - sizeof(struct ipv6hdr)) goto drop; - } if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr))) goto drop;