[src/trunk]: src/sys/dev/usb usbdi(9): Fix mistake in previous change to usbd...

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

details:   https://anonhg.NetBSD.org/src/rev/2cc754335598
branches:  trunk
changeset: 363479:2cc754335598
user:      riastradh <riastradh%NetBSD.org@localhost>
date:      Sun Mar 13 13:18:22 2022 +0000

description:
usbdi(9): Fix mistake in previous change to usbd_fill_iface_data.

The previous change stopped and rejected any descriptors smaller than
an endpoint descriptor.  Restore the previous behaviour: just skip
over them (but it will now reject descriptors that are smaller than
_any_ descriptor, which is legitimately a hardware error).

diffstat:

 sys/dev/usb/usb_subr.c |  44 +++++++++++++++++++++++---------------------
 1 files changed, 23 insertions(+), 21 deletions(-)

diffs (81 lines):

diff -r 00817165837e -r 2cc754335598 sys/dev/usb/usb_subr.c
--- a/sys/dev/usb/usb_subr.c    Sun Mar 13 13:07:39 2022 +0000
+++ b/sys/dev/usb/usb_subr.c    Sun Mar 13 13:18:22 2022 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: usb_subr.c,v 1.272 2022/03/13 11:30:12 riastradh Exp $ */
+/*     $NetBSD: usb_subr.c,v 1.273 2022/03/13 13:18:22 riastradh Exp $ */
 /*     $FreeBSD: src/sys/dev/usb/usb_subr.c,v 1.18 1999/11/17 22:33:47 n_hibma Exp $   */
 
 /*
@@ -32,7 +32,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: usb_subr.c,v 1.272 2022/03/13 11:30:12 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: usb_subr.c,v 1.273 2022/03/13 13:18:22 riastradh Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_compat_netbsd.h"
@@ -531,7 +531,9 @@
        USBHIST_CALLARGS(usbdebug, "ifaceidx=%jd altidx=%jd",
            ifaceidx, altidx, 0, 0);
        struct usbd_interface *ifc = &dev->ud_ifaces[ifaceidx];
+       usb_descriptor_t *desc;
        usb_interface_descriptor_t *idesc;
+       usb_endpoint_descriptor_t *ed;
        struct usbd_endpoint *endpoints;
        char *p, *end;
        int endpt, nendpt;
@@ -556,33 +558,33 @@
        KASSERTMSG((char *)dev->ud_cdesc <= (char *)idesc, "cdesc=%p idesc=%p",
            dev->ud_cdesc, idesc);
        KASSERTMSG((char *)idesc < end, "idesc=%p end=%p", idesc, end);
-#define ed ((usb_endpoint_descriptor_t *)p)
        for (endpt = 0; endpt < nendpt; endpt++) {
                DPRINTFN(10, "endpt=%jd", endpt, 0, 0, 0);
-               for (; end - p >= sizeof(*ed); p += ed->bLength) {
+               for (; end - p >= sizeof(*desc); p += desc->bLength) {
                        DPRINTFN(10, "p=%#jx end=%#jx len=%jd type=%jd",
-                           (uintptr_t)p, (uintptr_t)end, ed->bLength,
-                           ed->bDescriptorType);
-                       if (ed->bLength < sizeof(*ed) ||
-                           ed->bLength > end - p ||
-                           ed->bDescriptorType == UDESC_INTERFACE)
-                               break;
-                       if (ed->bLength >= USB_ENDPOINT_DESCRIPTOR_SIZE &&
-                           ed->bDescriptorType == UDESC_ENDPOINT)
-                               goto found;
-               }
-               /* passed end, or bad desc */
-               if (end - p >= sizeof(*ed)) {
-                       if (ed->bLength == 0) {
-                               printf("%s: bad descriptor: 0 length\n",
+                           (uintptr_t)p, (uintptr_t)end, desc->bLength,
+                           desc->bDescriptorType);
+                       desc = (usb_descriptor_t *)p;
+                       if (desc->bLength < sizeof(*desc)) {
+                               printf("%s: bad descriptor: too short\n",
                                    __func__);
-                       } else {
+                               goto bad;
+                       } else if (desc->bLength > end - p) {
+                               printf("%s: bad descriptor: too long\n",
+                                   __func__);
+                               goto bad;
+                       } else if (desc->bDescriptorType == UDESC_INTERFACE) {
                                printf("%s: bad descriptor: iface desc\n",
                                    __func__);
+                               goto bad;
                        }
-               } else {
-                       printf("%s: no desc found\n", __func__);
+                       if (desc->bLength >= USB_ENDPOINT_DESCRIPTOR_SIZE &&
+                           desc->bDescriptorType == UDESC_ENDPOINT) {
+                               ed = (usb_endpoint_descriptor_t *)p;
+                               goto found;
+                       }
                }
+               printf("%s: no desc found\n", __func__);
                goto bad;
        found:
                endpoints[endpt].ue_edesc = ed;