@@ -1627,6 +1627,7 @@ static void tcp_v6_fill_cb(struct sk_buff *skb, const struct ipv6hdr *hdr,
INDIRECT_CALLABLE_SCOPE int tcp_v6_rcv(struct sk_buff *skb)
{
+ enum skb_drop_reason drop_reason;
int sdif = inet6_sdif(skb);
int dif = inet6_iif(skb);
const struct tcphdr *th;
@@ -1636,6 +1637,7 @@ INDIRECT_CALLABLE_SCOPE int tcp_v6_rcv(struct sk_buff *skb)
int ret;
struct net *net = dev_net(skb->dev);
+ drop_reason = SKB_DROP_REASON_NOT_SPECIFIED;
if (skb->pkt_type != PACKET_HOST)
goto discard_it;
@@ -1649,8 +1651,10 @@ INDIRECT_CALLABLE_SCOPE int tcp_v6_rcv(struct sk_buff *skb)
th = (const struct tcphdr *)skb->data;
- if (unlikely(th->doff < sizeof(struct tcphdr)/4))
+ if (unlikely(th->doff < sizeof(struct tcphdr) / 4)) {
+ drop_reason = SKB_DROP_REASON_PKT_TOO_SMALL;
goto bad_packet;
+ }
if (!pskb_may_pull(skb, th->doff*4))
goto discard_it;
@@ -1706,6 +1710,8 @@ INDIRECT_CALLABLE_SCOPE int tcp_v6_rcv(struct sk_buff *skb)
hdr = ipv6_hdr(skb);
tcp_v6_fill_cb(skb, hdr, th);
nsk = tcp_check_req(sk, skb, req, false, &req_stolen);
+ } else {
+ drop_reason = SKB_DROP_REASON_SOCKET_FILTER;
}
if (!nsk) {
reqsk_put(req);
@@ -1741,14 +1747,18 @@ INDIRECT_CALLABLE_SCOPE int tcp_v6_rcv(struct sk_buff *skb)
}
}
- if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
+ if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) {
+ drop_reason = SKB_DROP_REASON_XFRM_POLICY;
goto discard_and_relse;
+ }
if (tcp_v6_inbound_md5_hash(sk, skb, dif, sdif))
goto discard_and_relse;
- if (tcp_filter(sk, skb))
+ if (tcp_filter(sk, skb)) {
+ drop_reason = SKB_DROP_REASON_SOCKET_FILTER;
goto discard_and_relse;
+ }
th = (const struct tcphdr *)skb->data;
hdr = ipv6_hdr(skb);
tcp_v6_fill_cb(skb, hdr, th);
@@ -1779,13 +1789,17 @@ INDIRECT_CALLABLE_SCOPE int tcp_v6_rcv(struct sk_buff *skb)
return ret ? -1 : 0;
no_tcp_socket:
- if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
+ drop_reason = SKB_DROP_REASON_NO_SOCKET;
+ if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
+ drop_reason = SKB_DROP_REASON_XFRM_POLICY;
goto discard_it;
+ }
tcp_v6_fill_cb(skb, hdr, th);
if (tcp_checksum_complete(skb)) {
csum_error:
+ drop_reason = SKB_DROP_REASON_TCP_CSUM;
trace_tcp_bad_csum(skb);
__TCP_INC_STATS(net, TCP_MIB_CSUMERRORS);
bad_packet:
@@ -1795,7 +1809,7 @@ INDIRECT_CALLABLE_SCOPE int tcp_v6_rcv(struct sk_buff *skb)
}
discard_it:
- kfree_skb(skb);
+ kfree_skb_reason(skb, drop_reason);
return 0;
discard_and_relse:
@@ -1806,6 +1820,7 @@ INDIRECT_CALLABLE_SCOPE int tcp_v6_rcv(struct sk_buff *skb)
do_time_wait:
if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
+ drop_reason = SKB_DROP_REASON_XFRM_POLICY;
inet_twsk_put(inet_twsk(sk));
goto discard_it;
}