diff options
| author | Hans Petter Selasky <hselasky@FreeBSD.org> | 2020-12-15 11:51:17 +0000 |
|---|---|---|
| committer | Hans Petter Selasky <hselasky@FreeBSD.org> | 2020-12-28 12:53:47 +0000 |
| commit | 4f89b6f56fb65c0b4a41875e21967a11ec28d837 (patch) | |
| tree | b118d6f12e9d9c93e2619dfbcb37022089f32bc5 | |
| parent | 931b121469a940147e34279783be6ac7343a980c (diff) | |
| download | src-4f89b6f56fb65c0b4a41875e21967a11ec28d837.tar.gz src-4f89b6f56fb65c0b4a41875e21967a11ec28d837.zip | |
MFC r368658:
Improve handling of alternate settings in the USB stack.
Limit the number of alternate settings to 256.
Else the alternate index variable may wrap around.
PR: 251856
Submitted by: Ma, Horse <Shichun.Ma@dell.com>
Sponsored by: Mellanox Technologies // NVIDIA Networking
| -rw-r--r-- | sys/dev/usb/usb_parse.c | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/sys/dev/usb/usb_parse.c b/sys/dev/usb/usb_parse.c index 5cace00fadc7..15bd1c967044 100644 --- a/sys/dev/usb/usb_parse.c +++ b/sys/dev/usb/usb_parse.c @@ -2,7 +2,7 @@ /*- * SPDX-License-Identifier: BSD-2-Clause-FreeBSD * - * Copyright (c) 2008 Hans Petter Selasky. All rights reserved. + * Copyright (c) 2008-2020 Hans Petter Selasky. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions @@ -141,8 +141,20 @@ usb_idesc_foreach(struct usb_config_descriptor *cd, break; if ((id->bDescriptorType == UDESC_INTERFACE) && (id->bLength >= sizeof(*id))) { - if (ps->iface_no_last == id->bInterfaceNumber) + if (ps->iface_no_last == id->bInterfaceNumber) { + /* + * Don't allow more than 256 alternate + * settings to avoid overflowing the + * alternate index which is a 8-bit + * variable. + */ + if (ps->iface_index_alt == 255) { + DPRINTF("Interface(%u) has more than 256 alternate settings\n", + id->bInterfaceNumber); + continue; + } new_iface = 0; + } ps->iface_no_last = id->bInterfaceNumber; break; } |