[src/trunk]: src/sys/dev/usb Fix error handling, to prevent kernel crashes wh...

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

details:   https://anonhg.NetBSD.org/src/rev/000e65012f1d
branches:  trunk
changeset: 459510:000e65012f1d
user:      maxv <maxv%NetBSD.org@localhost>
date:      Sat Sep 14 12:42:36 2019 +0000

description:
Fix error handling, to prevent kernel crashes when detaching an ural0
device.

Found with vHCI.

diffstat:

 sys/dev/usb/if_ural.c    |  10 ++++++++--
 sys/dev/usb/if_uralvar.h |   7 ++++++-
 2 files changed, 14 insertions(+), 3 deletions(-)

diffs (66 lines):

diff -r c36cf1bcab86 -r 000e65012f1d sys/dev/usb/if_ural.c
--- a/sys/dev/usb/if_ural.c     Sat Sep 14 12:41:32 2019 +0000
+++ b/sys/dev/usb/if_ural.c     Sat Sep 14 12:42:36 2019 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: if_ural.c,v 1.59 2019/05/05 03:17:54 mrg Exp $ */
+/*     $NetBSD: if_ural.c,v 1.60 2019/09/14 12:42:36 maxv Exp $ */
 /*     $FreeBSD: /repoman/r/ncvs/src/sys/dev/usb/if_ural.c,v 1.40 2006/06/02 23:14:40 sam Exp $        */
 
 /*-
@@ -24,7 +24,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_ural.c,v 1.59 2019/05/05 03:17:54 mrg Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_ural.c,v 1.60 2019/09/14 12:42:36 maxv Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_usb.h"
@@ -367,6 +367,7 @@
 
        sc->sc_dev = self;
        sc->sc_udev = uaa->uaa_device;
+       sc->sc_init_state = URAL_INIT_NONE;
 
        aprint_naive("\n");
        aprint_normal("\n");
@@ -513,6 +514,8 @@
 
        ieee80211_announce(ic);
 
+       sc->sc_init_state = URAL_INIT_INITED;
+
        usbd_add_drv_event(USB_EVENT_DRIVER_ATTACH, sc->sc_udev, sc->sc_dev);
 
        if (!pmf_device_register(self, NULL, NULL))
@@ -529,6 +532,9 @@
        struct ifnet *ifp = &sc->sc_if;
        int s;
 
+       if (sc->sc_init_state < URAL_INIT_INITED)
+               return 0;
+
        pmf_device_deregister(self);
 
        s = splusb();
diff -r c36cf1bcab86 -r 000e65012f1d sys/dev/usb/if_uralvar.h
--- a/sys/dev/usb/if_uralvar.h  Sat Sep 14 12:41:32 2019 +0000
+++ b/sys/dev/usb/if_uralvar.h  Sat Sep 14 12:42:36 2019 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: if_uralvar.h,v 1.12 2016/04/23 10:15:31 skrll Exp $ */
+/*     $NetBSD: if_uralvar.h,v 1.13 2019/09/14 12:42:36 maxv Exp $ */
 /*     $OpenBSD: if_ralvar.h,v 1.2 2005/05/13 18:42:50 damien Exp $  */
 
 /*-
@@ -74,6 +74,11 @@
        device_t                sc_dev;
        struct ethercom         sc_ec;
 #define sc_if  sc_ec.ec_if
+
+       enum {
+               URAL_INIT_NONE,
+               URAL_INIT_INITED
+       } sc_init_state;
        struct ieee80211com     sc_ic;
        int                     (*sc_newstate)(struct ieee80211com *,
                                    enum ieee80211_state, int);