Subject: [PATCH net-next v10 09/10] tcp: make the dropreason really work when calling tcp_rcv_state_process()

From: Jason Xing <[email-masked]>
Date: Mon, 26 Feb 2024 11:22:26 +0800

From: Jason Xing <[email-masked]>

Update three callers including both ipv4 and ipv6 and let the dropreason
mechanism work in reality.

Signed-off-by: Jason Xing <[email-masked]>
Reviewed-by: Eric Dumazet <[email-masked]>
Reviewed-by: David Ahern <[email-masked]>
Reviewed-by: Kuniyuki Iwashima <[email-masked]>
--
v10
Link: https://lore.kernel.org/netdev/[email-masked]/
1. nit, fix the indendation problem (Kuniyuki)
2. add reviewed-by tag (Kuniyuki)
--
v9
Link: https://lore.kernel.org/netdev/[email-masked]/
1. add reviewed-by tag (David)

v8
Link: https://lore.kernel.org/netdev/CANn89i+Uikp=[email-masked]/
1. add reviewed-by tag (Eric)
---
 include/net/tcp.h        |  4 ++--
 net/ipv4/tcp_ipv4.c      |  3 ++-
 net/ipv4/tcp_minisocks.c | 10 +++++-----
 net/ipv6/tcp_ipv6.c      |  3 ++-
 4 files changed, 11 insertions(+), 9 deletions(-)

diff --git a/include/net/tcp.h b/include/net/tcp.h
index af2a4dcd4518..6ae35199d3b3 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -396,8 +396,8 @@ enum tcp_tw_status tcp_timewait_state_process(struct inet_timewait_sock *tw,
 struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb,
 			   struct request_sock *req, bool fastopen,
 			   bool *lost_race);
-int tcp_child_process(struct sock *parent, struct sock *child,
-		      struct sk_buff *skb);
+enum skb_drop_reason tcp_child_process(struct sock *parent, struct sock *child,
+				       struct sk_buff *skb);
 void tcp_enter_loss(struct sock *sk);
 void tcp_cwnd_reduction(struct sock *sk, int newly_acked_sacked, int newly_lost, int flag);
 void tcp_clear_retrans(struct tcp_sock *tp);
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 0a944e109088..c79e25549972 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -1926,7 +1926,8 @@ int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb)
 	} else
 		sock_rps_save_rxhash(sk, skb);
 
-	if (tcp_rcv_state_process(sk, skb)) {
+	reason = tcp_rcv_state_process(sk, skb);
+	if (reason) {
 		rsk = sk;
 		goto reset;
 	}
diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c
index 9e85f2a0bddd..52040b0e2616 100644
--- a/net/ipv4/tcp_minisocks.c
+++ b/net/ipv4/tcp_minisocks.c
@@ -911,11 +911,11 @@ EXPORT_SYMBOL(tcp_check_req);
  * be created.
  */
 
-int tcp_child_process(struct sock *parent, struct sock *child,
-		      struct sk_buff *skb)
+enum skb_drop_reason tcp_child_process(struct sock *parent, struct sock *child,
+				       struct sk_buff *skb)
 	__releases(&((child)->sk_lock.slock))
 {
-	int ret = 0;
+	enum skb_drop_reason reason = SKB_NOT_DROPPED_YET;
 	int state = child->sk_state;
 
 	/* record sk_napi_id and sk_rx_queue_mapping of child. */
@@ -923,7 +923,7 @@ int tcp_child_process(struct sock *parent, struct sock *child,
 
 	tcp_segs_in(tcp_sk(child), skb);
 	if (!sock_owned_by_user(child)) {
-		ret = tcp_rcv_state_process(child, skb);
+		reason = tcp_rcv_state_process(child, skb);
 		/* Wakeup parent, send SIGIO */
 		if (state == TCP_SYN_RECV && child->sk_state != state)
 			parent->sk_data_ready(parent);
@@ -937,6 +937,6 @@ int tcp_child_process(struct sock *parent, struct sock *child,
 
 	bh_unlock_sock(child);
 	sock_put(child);
-	return ret;
+	return reason;
 }
 EXPORT_SYMBOL(tcp_child_process);
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 0c180bb8187f..4f8464e04b7f 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -1663,7 +1663,8 @@ int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
 	} else
 		sock_rps_save_rxhash(sk, skb);
 
-	if (tcp_rcv_state_process(sk, skb))
+	reason = tcp_rcv_state_process(sk, skb);
+	if (reason)
 		goto reset;
 	if (opt_skb)
 		goto ipv6_pktoptions;
-- 
2.37.3