diff mbox series

[net-next,4/9] net: tcp: store drop reasons in tcp_rcv_synsent_state_process()

Message ID 20221029130957.1292060-5-imagedong@tencent.com (mailing list archive)
State Changes Requested
Delegated to: Netdev Maintainers
Headers show
Series net: tcp: add skb drop reasons to tcp state process | expand

Checks

Context Check Description
netdev/tree_selection success Clearly marked for net-next, async
netdev/fixes_present success Fixes tag not required for -next series
netdev/subject_prefix success Link
netdev/cover_letter success Series has a cover letter
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 5331 this patch: 5331
netdev/cc_maintainers success CCed 7 of 7 maintainers
netdev/build_clang success Errors and warnings before: 1119 this patch: 1119
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 5513 this patch: 5513
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 36 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Menglong Dong Oct. 29, 2022, 1:09 p.m. UTC 
From: Menglong Dong <imagedong@tencent.com>

The skb drop reasons for the 'reset' code path in
tcp_rcv_synsent_state_process() is not handled yet. Now, we can store the
drop reason to tcp_skb_cb for such case.

The new reason 'TCP_PAWSACTIVEREJECTED' is added, which is corresponding
to LINUX_MIB_PAWSACTIVEREJECTED.

Signed-off-by: Menglong Dong <imagedong@tencent.com>
---
 include/net/dropreason.h | 7 +++++++
 net/ipv4/tcp_input.c     | 5 +++++
 2 files changed, 12 insertions(+)
diff mbox series

Patch

diff --git a/include/net/dropreason.h b/include/net/dropreason.h
index c1cbcdbaf149..0f0edcd5f95f 100644
--- a/include/net/dropreason.h
+++ b/include/net/dropreason.h
@@ -68,6 +68,7 @@ 
 	FN(IP_INADDRERRORS)		\
 	FN(IP_INNOROUTES)		\
 	FN(PKT_TOO_BIG)			\
+	FN(TCP_PAWSACTIVEREJECTED)	\
 	FNe(MAX)
 
 /**
@@ -298,6 +299,12 @@  enum skb_drop_reason {
 	 * MTU)
 	 */
 	SKB_DROP_REASON_PKT_TOO_BIG,
+	/**
+	 * @SKB_DROP_REASON_TCP_PAWSACTIVEREJECTED: PAWS check failed for
+	 * active TCP connection, corresponding to
+	 * LINUX_MIB_PAWSACTIVEREJECTED
+	 */
+	SKB_DROP_REASON_TCP_PAWSACTIVEREJECTED,
 	/**
 	 * @SKB_DROP_REASON_MAX: the maximum of drop reason, which shouldn't be
 	 * used as a real 'reason'
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 0640453fce54..c0e5c4a29a4e 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -6195,6 +6195,10 @@  static int tcp_rcv_synsent_state_process(struct sock *sk, struct sk_buff *skb,
 				inet_csk_reset_xmit_timer(sk,
 						ICSK_TIME_RETRANS,
 						TCP_TIMEOUT_MIN, TCP_RTO_MAX);
+			if (after(TCP_SKB_CB(skb)->ack_seq, tp->snd_nxt))
+				TCP_SKB_DR(skb, TCP_ACK_UNSENT_DATA);
+			else
+				TCP_SKB_DR(skb, TCP_TOO_OLD_ACK);
 			goto reset_and_undo;
 		}
 
@@ -6203,6 +6207,7 @@  static int tcp_rcv_synsent_state_process(struct sock *sk, struct sk_buff *skb,
 			     tcp_time_stamp(tp))) {
 			NET_INC_STATS(sock_net(sk),
 					LINUX_MIB_PAWSACTIVEREJECTED);
+			TCP_SKB_DR(skb, TCP_PAWSACTIVEREJECTED);
 			goto reset_and_undo;
 		}