Commit c026c656 authored by Jason Xing's avatar Jason Xing Committed by David S. Miller
Browse files

tcp: rstreason: introduce SK_RST_REASON_TCP_DISCONNECT_WITH_DATA for active reset 



When user tries to disconnect a socket and there are more data written
into tcp write queue, we should tell users about this reset reason.

Signed-off-by: default avatarJason Xing <kernelxing@tencent.com>
Reviewed-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 0a399892

include/net/rstreason.h

+8 −0
Original line number Diff line number Diff line
@@ -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

net/ipv4/tcp.c

+2 −1
Original line number Diff line number Diff line
@@ -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);