[src/trunk]: src/sys/dev/usb Fix ugen detach after partial attach.

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

details:   https://anonhg.NetBSD.org/src/rev/3138a21b1084
branches:  trunk
changeset: 937427:3138a21b1084
user:      riastradh <riastradh%NetBSD.org@localhost>
date:      Tue Aug 18 14:32:34 2020 +0000

description:
Fix ugen detach after partial attach.

While here, register null pmf handler even for partially attached
devices so they don't needlessly interfere with suspend.

Reported-by: syzbot+5a091d2e62da20b77259%syzkaller.appspotmail.com@localhost

diffstat:

 sys/dev/usb/ugen.c |  21 ++++++++++++---------
 1 files changed, 12 insertions(+), 9 deletions(-)

diffs (82 lines):

diff -r 897c067ddc0e -r 3138a21b1084 sys/dev/usb/ugen.c
--- a/sys/dev/usb/ugen.c        Tue Aug 18 11:48:21 2020 +0000
+++ b/sys/dev/usb/ugen.c        Tue Aug 18 14:32:34 2020 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: ugen.c,v 1.156 2020/08/16 06:17:31 riastradh Exp $     */
+/*     $NetBSD: ugen.c,v 1.157 2020/08/18 14:32:34 riastradh Exp $     */
 
 /*
  * Copyright (c) 1998, 2004 The NetBSD Foundation, Inc.
@@ -37,7 +37,7 @@
 
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: ugen.c,v 1.156 2020/08/16 06:17:31 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: ugen.c,v 1.157 2020/08/18 14:32:34 riastradh Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_compat_netbsd.h"
@@ -139,6 +139,7 @@
        int sc_refcnt;
        char sc_buffer[UGEN_BBSIZE];
        u_char sc_dying;
+       u_char sc_attached;
 };
 
 static struct {
@@ -379,6 +380,9 @@
                }
        }
 
+       if (!pmf_device_register(self, NULL, NULL))
+               aprint_error_dev(self, "couldn't establish power handler\n");
+
        if (uiaa->uiaa_ifaceno < 0) {
                /*
                 * If we attach the whole device,
@@ -388,7 +392,6 @@
                if (err) {
                        aprint_error_dev(self,
                            "setting configuration index 0 failed\n");
-                       sc->sc_dying = 1;
                        return;
                }
        }
@@ -401,16 +404,12 @@
        if (err) {
                aprint_error_dev(self, "setting configuration %d failed\n",
                    conf);
-               sc->sc_dying = 1;
                return;
        }
 
        ugenif_get_unit(sc);
        usbd_add_drv_event(USB_EVENT_DRIVER_ATTACH, sc->sc_udev, sc->sc_dev);
-
-       if (!pmf_device_register(self, NULL, NULL))
-               aprint_error_dev(self, "couldn't establish power handler\n");
-
+       sc->sc_attached = 1;
 }
 
 Static void
@@ -1143,6 +1142,10 @@
 
        sc->sc_dying = 1;
        pmf_device_deregister(self);
+
+       if (!sc->sc_attached)
+               goto out;
+
        /* Abort all pipes.  Causes processes waiting for transfer to wake. */
        for (i = 0; i < USB_MAX_ENDPOINTS; i++) {
                for (dir = OUT; dir <= IN; dir++) {
@@ -1173,7 +1176,7 @@
        usbd_add_drv_event(USB_EVENT_DRIVER_DETACH, sc->sc_udev, sc->sc_dev);
        ugenif_put_unit(sc);
 
-       for (i = 0; i < USB_MAX_ENDPOINTS; i++) {
+out:   for (i = 0; i < USB_MAX_ENDPOINTS; i++) {
                for (dir = OUT; dir <= IN; dir++) {
                        sce = &sc->sc_endpoints[i][dir];
                        seldestroy(&sce->rsel);