diff options
Diffstat (limited to 'net/ipv4/tcp_ipv4.c')
| -rw-r--r-- | net/ipv4/tcp_ipv4.c | 32 |
1 files changed, 24 insertions, 8 deletions
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 6873f46fc8ba..d42824aedc36 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -1412,7 +1412,8 @@ EXPORT_SYMBOL(tcp_v4_md5_hash_skb); /* Called with rcu_read_lock() */ static bool tcp_v4_inbound_md5_hash(const struct sock *sk, const struct sk_buff *skb, - int dif, int sdif) + int dif, int sdif, + enum skb_drop_reason *reason) { #ifdef CONFIG_TCP_MD5SIG /* @@ -1445,11 +1446,13 @@ static bool tcp_v4_inbound_md5_hash(const struct sock *sk, return false; if (hash_expected && !hash_location) { + *reason = SKB_DROP_REASON_TCP_MD5NOTFOUND; NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND); return true; } if (!hash_expected && hash_location) { + *reason = SKB_DROP_REASON_TCP_MD5UNEXPECTED; NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5UNEXPECTED); return true; } @@ -1462,6 +1465,7 @@ static bool tcp_v4_inbound_md5_hash(const struct sock *sk, NULL, skb); if (genhash || memcmp(hash_location, newhash, 16) != 0) { + *reason = SKB_DROP_REASON_TCP_MD5FAILURE; NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5FAILURE); net_info_ratelimited("MD5 Hash failed for (%pI4, %d)->(%pI4, %d)%s L3 index %d\n", &iph->saddr, ntohs(th->source), @@ -1704,6 +1708,7 @@ INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *, */ int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb) { + enum skb_drop_reason reason; struct sock *rsk; if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */ @@ -1726,6 +1731,7 @@ int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb) return 0; } + reason = SKB_DROP_REASON_NOT_SPECIFIED; if (tcp_checksum_complete(skb)) goto csum_err; @@ -1753,7 +1759,7 @@ int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb) reset: tcp_v4_send_reset(rsk, skb); discard: - kfree_skb(skb); + kfree_skb_reason(skb, reason); /* Be careful here. If this function gets more complicated and * gcc suffers from register pressure on the x86, sk (in %ebx) * might be destroyed here. This current version compiles correctly, @@ -1762,6 +1768,7 @@ discard: return 0; csum_err: + reason = SKB_DROP_REASON_TCP_CSUM; trace_tcp_bad_csum(skb); TCP_INC_STATS(sock_net(sk), TCP_MIB_CSUMERRORS); TCP_INC_STATS(sock_net(sk), TCP_MIB_INERRS); @@ -1807,7 +1814,8 @@ int tcp_v4_early_demux(struct sk_buff *skb) return 0; } -bool tcp_add_backlog(struct sock *sk, struct sk_buff *skb) +bool tcp_add_backlog(struct sock *sk, struct sk_buff *skb, + enum skb_drop_reason *reason) { u32 limit, tail_gso_size, tail_gso_segs; struct skb_shared_info *shinfo; @@ -1833,6 +1841,7 @@ bool tcp_add_backlog(struct sock *sk, struct sk_buff *skb) if (unlikely(tcp_checksum_complete(skb))) { bh_unlock_sock(sk); trace_tcp_bad_csum(skb); + *reason = SKB_DROP_REASON_TCP_CSUM; __TCP_INC_STATS(sock_net(sk), TCP_MIB_CSUMERRORS); __TCP_INC_STATS(sock_net(sk), TCP_MIB_INERRS); return true; @@ -1921,6 +1930,7 @@ no_coalesce: if (unlikely(sk_add_backlog(sk, skb, limit))) { bh_unlock_sock(sk); + *reason = SKB_DROP_REASON_SOCKET_BACKLOG; __NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPBACKLOGDROP); return true; } @@ -1971,13 +1981,13 @@ static void tcp_v4_fill_cb(struct sk_buff *skb, const struct iphdr *iph, int tcp_v4_rcv(struct sk_buff *skb) { struct net *net = dev_net(skb->dev); + enum skb_drop_reason drop_reason; int sdif = inet_sdif(skb); int dif = inet_iif(skb); const struct iphdr *iph; const struct tcphdr *th; bool refcounted; struct sock *sk; - int drop_reason; int ret; drop_reason = SKB_DROP_REASON_NOT_SPECIFIED; @@ -2025,7 +2035,8 @@ process: struct sock *nsk; sk = req->rsk_listener; - if (unlikely(tcp_v4_inbound_md5_hash(sk, skb, dif, sdif))) { + if (unlikely(tcp_v4_inbound_md5_hash(sk, skb, dif, sdif, + &drop_reason))) { sk_drops_add(sk, skb); reqsk_put(req); goto discard_it; @@ -2057,6 +2068,8 @@ process: iph = ip_hdr(skb); tcp_v4_fill_cb(skb, iph, th); nsk = tcp_check_req(sk, skb, req, false, &req_stolen); + } else { + drop_reason = SKB_DROP_REASON_SOCKET_FILTER; } if (!nsk) { reqsk_put(req); @@ -2092,10 +2105,12 @@ process: } } - if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) + if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) { + drop_reason = SKB_DROP_REASON_XFRM_POLICY; goto discard_and_relse; + } - if (tcp_v4_inbound_md5_hash(sk, skb, dif, sdif)) + if (tcp_v4_inbound_md5_hash(sk, skb, dif, sdif, &drop_reason)) goto discard_and_relse; nf_reset_ct(skb); @@ -2124,7 +2139,7 @@ process: if (!sock_owned_by_user(sk)) { ret = tcp_v4_do_rcv(sk, skb); } else { - if (tcp_add_backlog(sk, skb)) + if (tcp_add_backlog(sk, skb, &drop_reason)) goto discard_and_relse; } bh_unlock_sock(sk); @@ -2166,6 +2181,7 @@ discard_and_relse: do_time_wait: if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) { + drop_reason = SKB_DROP_REASON_XFRM_POLICY; inet_twsk_put(inet_twsk(sk)); goto discard_it; } |