[Devel] [PATCH 10/47] net: tcp: add skb drop reasons to tcp_v4_rcv()

[Nikolay Borisov]

From: Menglong Dong <imagedong at tencent.com>

Use kfree_skb_reason() for some path in tcp_v4_rcv() that missed before,
including:

SKB_DROP_REASON_SOCKET_FILTER
SKB_DROP_REASON_XFRM_POLICY

Reviewed-by: Mengen Sun <mengensun at tencent.com>
Reviewed-by: Hao Peng <flyingpeng at tencent.com>
Signed-off-by: Menglong Dong <imagedong at tencent.com>
Reviewed-by: Eric Dumazet <edumazet at google.com>
Reviewed-by: David Ahern <dsahern at kernel.org>
Signed-off-by: David S. Miller <davem at davemloft.net>
Acked-by: Nikolay Borisov <nborisov at suse.com>
Signed-off-by: Nikolay Borisov <nikolay.borisov at virtuozzo.com>
---
 net/ipv4/tcp_ipv4.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 4af44bb8228c..0267b0cc1da0 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -2043,6 +2043,8 @@ int tcp_v4_rcv(struct sk_buff *skb)
 			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);
@@ -2074,8 +2076,10 @@ int tcp_v4_rcv(struct sk_buff *skb)
 		goto discard_and_relse;
 	}
 
-	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))
 		goto discard_and_relse;
@@ -2147,6 +2151,7 @@ int tcp_v4_rcv(struct sk_buff *skb)
 
 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;
 	}
-- 
2.34.1