git: 04ede3675e44 - main - sctp: only start shutdown guard timer when sending SHUTDOWN chunk

From: Michael Tuexen <tuexen_at_FreeBSD.org>
Date: Wed, 03 May 2023 18:32:05 UTC
The branch main has been updated by tuexen:

URL: https://cgit.FreeBSD.org/src/commit/?id=04ede3675e44847c3e9e4a9bd44509cdf42ed60a

commit 04ede3675e44847c3e9e4a9bd44509cdf42ed60a
Author:     Michael Tuexen <tuexen@FreeBSD.org>
AuthorDate: 2023-05-03 18:28:46 +0000
Commit:     Michael Tuexen <tuexen@FreeBSD.org>
CommitDate: 2023-05-03 18:28:46 +0000

    sctp: only start shutdown guard timer when sending SHUTDOWN chunk
    
    The intention is to protect a malicious peer not following the
    shutdown procedures.
    
    MFC after:      1 week
---
 sys/netinet/sctp_input.c  | 14 --------------
 sys/netinet/sctp_output.c |  4 ----
 sys/netinet/sctp_pcb.c    |  1 -
 sys/netinet/sctp_usrreq.c |  6 +++---
 4 files changed, 3 insertions(+), 22 deletions(-)

diff --git a/sys/netinet/sctp_input.c b/sys/netinet/sctp_input.c
index fc362d091a22..5a7ed6ffde90 100644
--- a/sys/netinet/sctp_input.c
+++ b/sys/netinet/sctp_input.c
@@ -1501,10 +1501,6 @@ sctp_process_cookie_existing(struct mbuf *m, int iphlen, int offset,
 				SCTP_STAT_INCR_COUNTER32(sctps_collisionestab);
 
 			SCTP_SET_STATE(stcb, SCTP_STATE_OPEN);
-			if (asoc->state & SCTP_STATE_SHUTDOWN_PENDING) {
-				sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNGUARD,
-				    stcb->sctp_ep, stcb, NULL);
-			}
 			SCTP_STAT_INCR_GAUGE32(sctps_currestab);
 			sctp_stop_all_cookie_timers(stcb);
 			if (((stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_TCPTYPE) ||
@@ -1718,10 +1714,6 @@ sctp_process_cookie_existing(struct mbuf *m, int iphlen, int offset,
 			SCTP_STAT_INCR_COUNTER32(sctps_collisionestab);
 		}
 		SCTP_SET_STATE(stcb, SCTP_STATE_OPEN);
-		if (asoc->state & SCTP_STATE_SHUTDOWN_PENDING) {
-			sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNGUARD,
-			    stcb->sctp_ep, stcb, NULL);
-		}
 		sctp_stop_all_cookie_timers(stcb);
 		sctp_toss_old_cookies(stcb, asoc);
 		sctp_send_cookie_ack(stcb);
@@ -1788,8 +1780,6 @@ sctp_process_cookie_existing(struct mbuf *m, int iphlen, int offset,
 		}
 		if (asoc->state & SCTP_STATE_SHUTDOWN_PENDING) {
 			SCTP_SET_STATE(stcb, SCTP_STATE_OPEN);
-			sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNGUARD,
-			    stcb->sctp_ep, stcb, NULL);
 
 		} else if (SCTP_GET_STATE(stcb) != SCTP_STATE_SHUTDOWN_SENT) {
 			/* move to OPEN state, if not in SHUTDOWN_SENT */
@@ -2176,10 +2166,6 @@ sctp_process_cookie_new(struct mbuf *m, int iphlen, int offset,
 	/* update current state */
 	SCTPDBG(SCTP_DEBUG_INPUT2, "moving to OPEN state\n");
 	SCTP_SET_STATE(stcb, SCTP_STATE_OPEN);
-	if (asoc->state & SCTP_STATE_SHUTDOWN_PENDING) {
-		sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNGUARD,
-		    stcb->sctp_ep, stcb, NULL);
-	}
 	sctp_stop_all_cookie_timers(stcb);
 	SCTP_STAT_INCR_COUNTER32(sctps_passiveestab);
 	SCTP_STAT_INCR_GAUGE32(sctps_currestab);
diff --git a/sys/netinet/sctp_output.c b/sys/netinet/sctp_output.c
index 3b9a06b72d8a..fdea88002194 100644
--- a/sys/netinet/sctp_output.c
+++ b/sys/netinet/sctp_output.c
@@ -6768,8 +6768,6 @@ sctp_sendall_iterator(struct sctp_inpcb *inp, struct sctp_tcb *stcb, void *ptr,
 						atomic_subtract_int(&stcb->asoc.refcnt, 1);
 						goto no_chunk_output;
 					}
-					sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNGUARD, stcb->sctp_ep, stcb,
-					    NULL);
 				}
 			}
 		}
@@ -13562,8 +13560,6 @@ dataless_eof:
 					error = ECONNABORTED;
 					goto out;
 				}
-				sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNGUARD, stcb->sctp_ep, stcb,
-				    NULL);
 				sctp_feature_off(inp, SCTP_PCB_FLAGS_NODELAY);
 			}
 		}
diff --git a/sys/netinet/sctp_pcb.c b/sys/netinet/sctp_pcb.c
index 7567764bfd72..4e97dc4e7ad3 100644
--- a/sys/netinet/sctp_pcb.c
+++ b/sys/netinet/sctp_pcb.c
@@ -3461,7 +3461,6 @@ sctp_inpcb_free(struct sctp_inpcb *inp, int immediate, int from)
 			} else {
 				/* mark into shutdown pending */
 				SCTP_ADD_SUBSTATE(stcb, SCTP_STATE_SHUTDOWN_PENDING);
-				sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNGUARD, stcb->sctp_ep, stcb, NULL);
 				if ((*stcb->asoc.ss_functions.sctp_ss_is_user_msgs_incomplete) (stcb, &stcb->asoc)) {
 					SCTP_ADD_SUBSTATE(stcb, SCTP_STATE_PARTIAL_MSG_LEFT);
 				}
diff --git a/sys/netinet/sctp_usrreq.c b/sys/netinet/sctp_usrreq.c
index 6e17545c9a3b..917d301a85dc 100644
--- a/sys/netinet/sctp_usrreq.c
+++ b/sys/netinet/sctp_usrreq.c
@@ -736,7 +736,7 @@ sctp_disconnect(struct socket *so)
 					    stcb->sctp_ep, stcb, netp);
 					sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNGUARD,
 					    stcb->sctp_ep, stcb, NULL);
-					sctp_chunk_output(stcb->sctp_ep, stcb, SCTP_OUTPUT_FROM_T3, SCTP_SO_LOCKED);
+					sctp_chunk_output(stcb->sctp_ep, stcb, SCTP_OUTPUT_FROM_CLOSING, SCTP_SO_LOCKED);
 				}
 			} else {
 				/*
@@ -750,7 +750,6 @@ sctp_disconnect(struct socket *so)
 				 * and move to SHUTDOWN-PENDING
 				 */
 				SCTP_ADD_SUBSTATE(stcb, SCTP_STATE_SHUTDOWN_PENDING);
-				sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNGUARD, stcb->sctp_ep, stcb, NULL);
 				if ((*asoc->ss_functions.sctp_ss_is_user_msgs_incomplete) (stcb, asoc)) {
 					SCTP_ADD_SUBSTATE(stcb, SCTP_STATE_PARTIAL_MSG_LEFT);
 				}
@@ -933,6 +932,8 @@ sctp_shutdown(struct socket *so)
 			sctp_send_shutdown(stcb, netp);
 			sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWN,
 			    stcb->sctp_ep, stcb, netp);
+			sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNGUARD,
+			    stcb->sctp_ep, stcb, NULL);
 		} else {
 			/*
 			 * We still got (or just got) data to send, so set
@@ -957,7 +958,6 @@ sctp_shutdown(struct socket *so)
 				return (0);
 			}
 		}
-		sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNGUARD, stcb->sctp_ep, stcb, NULL);
 		/*
 		 * XXX: Why do this in the case where we have still data
 		 * queued?