[PATCH net-next v3 6/7] tcp: rstreason: introduce SK_RST_REASON_TCP_DISCONNECT_WITH_DATA for active reset
From: Jason Xing <hidden>
Date: 2024-08-01 14:55:08
Subsystem:
networking [general], networking [tcp], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Neal Cardwell, Linus Torvalds
From: Jason Xing <kernelxing@tencent.com> When user tries to disconnect a socket and there are more data written into tcp write queue, we have to send an RST. Signed-off-by: Jason Xing <kernelxing@tencent.com> -- v3 Link: Link: https://lore.kernel.org/all/20240731120955.23542-5-kerneljasonxing@gmail.com/ (local) 1. This case is different from previous patch, so we need to write it into a new patch. (Eric) --- include/net/rstreason.h | 8 ++++++++ net/ipv4/tcp.c | 3 ++- 2 files changed, 10 insertions(+), 1 deletion(-)
diff --git a/include/net/rstreason.h b/include/net/rstreason.h
index 9c0c46df0e73..69cb2e52b7da 100644
--- a/include/net/rstreason.h
+++ b/include/net/rstreason.h@@ -22,6 +22,7 @@ FN(TCP_ABORT_ON_MEMORY) \ FN(TCP_STATE) \ FN(TCP_KEEPALIVE_TIMEOUT) \ + FN(TCP_DISCONNECT_WITH_DATA) \ FN(MPTCP_RST_EUNSPEC) \ FN(MPTCP_RST_EMPTCP) \ FN(MPTCP_RST_ERESOURCE) \
@@ -115,6 +116,13 @@ enum sk_rst_reason { * keepalive timeout, we have to reset the connection */ SK_RST_REASON_TCP_KEEPALIVE_TIMEOUT, + /** + * @SK_RST_REASON_TCP_DISCONNECT_WITH_DATA: disconnect when write + * queue is not empty + * It means user has written data into the write queue when doing + * disconnecting, so we have to send an RST. + */ + SK_RST_REASON_TCP_DISCONNECT_WITH_DATA, /* Copy from include/uapi/linux/mptcp.h. * These reset fields will not be changed since they adhere to
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 24777e48bcc8..8514257f4ecd 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c@@ -3033,7 +3033,8 @@ int tcp_disconnect(struct sock *sk, int flags) /* The last check adjusts for discrepancy of Linux wrt. RFC * states */ - tcp_send_active_reset(sk, gfp_any(), SK_RST_REASON_NOT_SPECIFIED); + tcp_send_active_reset(sk, gfp_any(), + SK_RST_REASON_TCP_DISCONNECT_WITH_DATA); WRITE_ONCE(sk->sk_err, ECONNRESET); } else if (old_state == TCP_SYN_SENT) WRITE_ONCE(sk->sk_err, ECONNRESET);
--
2.37.3