[PATCH net-next v8 06/10] tcp: introduce dropreasons in receive path

[Jason Xing <kerneljasonxing@gmail.com>]

From: Jason Xing <kernelxing@tencent.com>

Soon later patches can use these relatively more accurate
reasons to recognise and find out the cause.

Signed-off-by: Jason Xing <kernelxing@tencent.com>
--
v7
Link: https://lore.kernel.org/all/20240219044744.99367-1-kuniyu@amazon.com/
1. nit: nit: s/. because of/ because/ (Kuniyuki)

v5:
Link: https://lore.kernel.org/netdev/3a495358-4c47-4a9f-b116-5f9c8b44e5ab@kernel.org/
1. Use new name (TCP_ABORT_ON_DATA) for readability (David)
2. change the title of this patch
---
 include/net/dropreason-core.h | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/include/net/dropreason-core.h b/include/net/dropreason-core.h
index a871f061558d..af7c7146219d 100644
--- a/include/net/dropreason-core.h
+++ b/include/net/dropreason-core.h
@@ -30,6 +30,7 @@
 	FN(TCP_AOFAILURE)		\
 	FN(SOCKET_BACKLOG)		\
 	FN(TCP_FLAGS)			\
+	FN(TCP_ABORT_ON_DATA)	\
 	FN(TCP_ZEROWINDOW)		\
 	FN(TCP_OLD_DATA)		\
 	FN(TCP_OVERWINDOW)		\
@@ -37,6 +38,7 @@
 	FN(TCP_RFC7323_PAWS)		\
 	FN(TCP_OLD_SEQUENCE)		\
 	FN(TCP_INVALID_SEQUENCE)	\
+	FN(TCP_INVALID_ACK_SEQUENCE)	\
 	FN(TCP_RESET)			\
 	FN(TCP_INVALID_SYN)		\
 	FN(TCP_CLOSE)			\
@@ -204,6 +206,11 @@ enum skb_drop_reason {
 	SKB_DROP_REASON_SOCKET_BACKLOG,
 	/** @SKB_DROP_REASON_TCP_FLAGS: TCP flags invalid */
 	SKB_DROP_REASON_TCP_FLAGS,
+	/**
+	 * @SKB_DROP_REASON_TCP_ABORT_ON_DATA: abort on data, corresponding to
+	 * LINUX_MIB_TCPABORTONDATA
+	 */
+	SKB_DROP_REASON_TCP_ABORT_ON_DATA,
 	/**
 	 * @SKB_DROP_REASON_TCP_ZEROWINDOW: TCP receive window size is zero,
 	 * see LINUX_MIB_TCPZEROWINDOWDROP
@@ -228,13 +235,19 @@ enum skb_drop_reason {
 	SKB_DROP_REASON_TCP_OFOMERGE,
 	/**
 	 * @SKB_DROP_REASON_TCP_RFC7323_PAWS: PAWS check, corresponding to
-	 * LINUX_MIB_PAWSESTABREJECTED
+	 * LINUX_MIB_PAWSESTABREJECTED, LINUX_MIB_PAWSACTIVEREJECTED
 	 */
 	SKB_DROP_REASON_TCP_RFC7323_PAWS,
 	/** @SKB_DROP_REASON_TCP_OLD_SEQUENCE: Old SEQ field (duplicate packet) */
 	SKB_DROP_REASON_TCP_OLD_SEQUENCE,
 	/** @SKB_DROP_REASON_TCP_INVALID_SEQUENCE: Not acceptable SEQ field */
 	SKB_DROP_REASON_TCP_INVALID_SEQUENCE,
+	/**
+	 * @SKB_DROP_REASON_TCP_INVALID_ACK_SEQUENCE: Not acceptable ACK SEQ
+	 * field because ack sequence is not in the window between snd_una
+	 * and snd_nxt
+	 */
+	SKB_DROP_REASON_TCP_INVALID_ACK_SEQUENCE,
 	/** @SKB_DROP_REASON_TCP_RESET: Invalid RST packet */
 	SKB_DROP_REASON_TCP_RESET,
 	/**
-- 
2.37.3