[src/trunk]: src/sys/net Stop ppp layer at first of destroying pppoe interface

[yamaguchi <yamaguchi%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/4af01ee839b9
branches:  trunk
changeset: 1020563:4af01ee839b9
user:      yamaguchi <yamaguchi%NetBSD.org@localhost>
date:      Fri Apr 16 01:59:50 2021 +0000

description:
Stop ppp layer at first of destroying pppoe interface

diffstat:

 sys/net/if_pppoe.c |  35 +++++++++++++++++++++++++++--------
 1 files changed, 27 insertions(+), 8 deletions(-)

diffs (93 lines):

diff -r e695bfb29853 -r 4af01ee839b9 sys/net/if_pppoe.c
--- a/sys/net/if_pppoe.c        Fri Apr 16 01:44:35 2021 +0000
+++ b/sys/net/if_pppoe.c        Fri Apr 16 01:59:50 2021 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: if_pppoe.c,v 1.166 2021/04/16 01:44:35 yamaguchi Exp $ */
+/* $NetBSD: if_pppoe.c,v 1.167 2021/04/16 01:59:50 yamaguchi Exp $ */
 
 /*
  * Copyright (c) 2002, 2008 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_pppoe.c,v 1.166 2021/04/16 01:44:35 yamaguchi Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_pppoe.c,v 1.167 2021/04/16 01:59:50 yamaguchi Exp $");
 
 #ifdef _KERNEL_OPT
 #include "pppoe.h"
@@ -188,6 +188,7 @@
        int sc_padi_retried;            /* number of PADI retries already done */
        int sc_padr_retried;            /* number of PADR retries already done */
        krwlock_t sc_lock;      /* lock of sc_state, sc_session, and sc_eth_if */
+       bool sc_detaching;
 };
 
 /* incoming traffic will be queued here */
@@ -417,13 +418,17 @@
 {
        struct pppoe_softc * sc = ifp->if_softc;
 
-       rw_enter(&pppoe_softc_list_lock, RW_WRITER);
+       PPPOE_LOCK(sc, RW_WRITER);
+       /* stop ioctls */
+       sc->sc_detaching = true;
 
-       PPPOE_LOCK(sc, RW_WRITER);
-       callout_setfunc(&sc->sc_timeout, pppoe_timeout_co_halt, sc);
-       workqueue_wait(sc->sc_timeout_wq, &sc->sc_timeout_wk);
-       callout_halt(&sc->sc_timeout, NULL);
+       if (ifp->if_flags & IFF_RUNNING) {
+               pppoe_clear_softc(sc, "destroy interface");
+               sc->sc_eth_if = NULL;
+       }
+       PPPOE_UNLOCK(sc);
 
+       rw_enter(&pppoe_softc_list_lock, RW_WRITER);
        LIST_REMOVE(sc, sc_list);
 
        if (LIST_EMPTY(&pppoe_softc_list)) {
@@ -431,6 +436,11 @@
        }
        rw_exit(&pppoe_softc_list_lock);
 
+       PPPOE_LOCK(sc, RW_WRITER);
+       callout_setfunc(&sc->sc_timeout, pppoe_timeout_co_halt, sc);
+       workqueue_wait(sc->sc_timeout_wq, &sc->sc_timeout_wk);
+       callout_halt(&sc->sc_timeout, NULL);
+
        bpf_detach(ifp);
        sppp_detach(&sc->sc_sppp.pp_if);
        if_detach(ifp);
@@ -1285,6 +1295,10 @@
                        struct ifnet *eth_if;
 
                        PPPOE_LOCK(sc, RW_WRITER);
+                       if (sc->sc_detaching) {
+                               PPPOE_UNLOCK(sc);
+                               return ENXIO;
+                       }
                        eth_if = ifunit(parms->eth_ifname);
                        if (eth_if == NULL || eth_if->if_dlt != DLT_EN10MB) {
                                sc->sc_eth_if = NULL;
@@ -1343,6 +1357,10 @@
                 * administrators choice.
                 */
                PPPOE_LOCK(sc, RW_WRITER);
+               if (sc->sc_detaching) {
+                       PPPOE_UNLOCK(sc);
+                       return ENXIO;
+               }
 
                if ((ifr->ifr_flags & IFF_UP) == 0
                     && sc->sc_state < PPPOE_STATE_SESSION) {
@@ -1506,7 +1524,8 @@
        switch (sc->sc_state) {
        case PPPOE_STATE_INITIAL:
                /* delayed connect from pppoe_tls() */
-               pppoe_connect(sc);
+               if (!sc->sc_detaching)
+                       pppoe_connect(sc);
                break;
        case PPPOE_STATE_PADI_SENT:
                /*