[PATCH net-next 9/9] net: ipv6: add skb drop reasons to ip6_protocol_deliver_rcu()

From: menglong8 . dong
Date: Wed Apr 13 2022 - 04:45:04 EST


From: Menglong Dong <imagedong@xxxxxxxxxxx>

Replace kfree_skb() used in ip6_protocol_deliver_rcu() with
kfree_skb_reason().

No new reasons are added.

Some paths are ignored, as they are not common, such as encapsulation
on non-final protocol.

Signed-off-by: Menglong Dong <imagedong@xxxxxxxxxxx>
Reviewed-by: Jiang Biao <benbjiang@xxxxxxxxxxx>
Reviewed-by: Hao Peng <flyingpeng@xxxxxxxxxxx>
---
net/ipv6/ip6_input.c | 16 ++++++++++++----
1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/net/ipv6/ip6_input.c b/net/ipv6/ip6_input.c
index 1b925ecb26e9..126ae3aa67e1 100644
--- a/net/ipv6/ip6_input.c
+++ b/net/ipv6/ip6_input.c
@@ -362,6 +362,7 @@ void ip6_protocol_deliver_rcu(struct net *net, struct sk_buff *skb, int nexthdr,
const struct inet6_protocol *ipprot;
struct inet6_dev *idev;
unsigned int nhoff;
+ SKB_DR(reason);
bool raw;

/*
@@ -421,12 +422,16 @@ void ip6_protocol_deliver_rcu(struct net *net, struct sk_buff *skb, int nexthdr,
if (ipv6_addr_is_multicast(&hdr->daddr) &&
!ipv6_chk_mcast_addr(dev, &hdr->daddr,
&hdr->saddr) &&
- !ipv6_is_mld(skb, nexthdr, skb_network_header_len(skb)))
+ !ipv6_is_mld(skb, nexthdr, skb_network_header_len(skb))) {
+ SKB_DR_SET(reason, IP_INADDRERRORS);
goto discard;
+ }
}
if (!(ipprot->flags & INET6_PROTO_NOPOLICY) &&
- !xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
+ !xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
+ SKB_DR_SET(reason, XFRM_POLICY);
goto discard;
+ }

ret = INDIRECT_CALL_2(ipprot->handler, tcp_v6_rcv, udpv6_rcv,
skb);
@@ -452,8 +457,11 @@ void ip6_protocol_deliver_rcu(struct net *net, struct sk_buff *skb, int nexthdr,
IPSTATS_MIB_INUNKNOWNPROTOS);
icmpv6_send(skb, ICMPV6_PARAMPROB,
ICMPV6_UNK_NEXTHDR, nhoff);
+ SKB_DR_SET(reason, IP_NOPROTO);
+ } else {
+ SKB_DR_SET(reason, XFRM_POLICY);
}
- kfree_skb(skb);
+ kfree_skb_reason(skb, reason);
} else {
__IP6_INC_STATS(net, idev, IPSTATS_MIB_INDELIVERS);
consume_skb(skb);
@@ -463,7 +471,7 @@ void ip6_protocol_deliver_rcu(struct net *net, struct sk_buff *skb, int nexthdr,

discard:
__IP6_INC_STATS(net, idev, IPSTATS_MIB_INDISCARDS);
- kfree_skb(skb);
+ kfree_skb_reason(skb, reason);
}

static int ip6_input_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
--
2.35.1