diff options
| author | Gerald Combs <gerald@wireshark.org> | 2020-07-08 10:12:23 -0700 |
|---|---|---|
| committer | Anders Broman <a.broman58@gmail.com> | 2020-07-09 06:20:48 +0000 |
| commit | 455a4794d810529313c900828fff1b097a363a50 (patch) | |
| tree | bc2edd8e25e2fffaaa350136a7d16235c47382ac /epan/dissectors/packet-usb.c | |
| parent | 4cf092382d6ab3a01c6cb132ae1ec211f7c1fc7c (diff) | |
USB: Add a size check.
In dissect_usbpcap_iso_packets check for a sane isochronous packet
count, otherwise we might overflow our data start offset.
Bug: 16677
Change-Id: I79534b4a519eefcf85cf4dd03424ac654bacd8c9
Reviewed-on: https://code.wireshark.org/review/37789
Reviewed-by: Gerald Combs <gerald@wireshark.org>
Petri-Dish: Gerald Combs <gerald@wireshark.org>
Tested-by: Petri Dish Buildbot
Reviewed-by: Anders Broman <a.broman58@gmail.com>
Diffstat (limited to 'epan/dissectors/packet-usb.c')
| -rw-r--r-- | epan/dissectors/packet-usb.c | 16 |
1 files changed, 12 insertions, 4 deletions
diff --git a/epan/dissectors/packet-usb.c b/epan/dissectors/packet-usb.c index 4f7f841b50..8da4e8a049 100644 --- a/epan/dissectors/packet-usb.c +++ b/epan/dissectors/packet-usb.c @@ -372,6 +372,7 @@ static expert_field ei_usb_desc_length_invalid = EI_INIT; static expert_field ei_usb_invalid_setup = EI_INIT; static expert_field ei_usb_ss_ep_companion_before_ep = EI_INIT; static expert_field ei_usb_usbpcap_unknown_urb = EI_INIT; +static expert_field ei_usb_bad_length = EI_INIT; static expert_field ei_usbport_invalid_path_depth = EI_INIT; @@ -4239,25 +4240,31 @@ static usb_trans_info_t /* dissect a group of isochronous packets inside an usb packet in usbpcap format */ +#define MAX_ISO_PACKETS 100000 // Arbitrary static gint dissect_usbpcap_iso_packets(packet_info *pinfo _U_, proto_tree *urb_tree, guint8 urb_type, tvbuff_t *tvb, gint offset, guint32 win32_data_len, usb_conv_info_t *usb_conv_info) { guint32 i; guint32 num_packets; - guint32 data_start_offset; - proto_item *urb_tree_ti; + int data_start_offset; + proto_item *num_packets_ti, *urb_tree_ti; proto_tree_add_item(urb_tree, hf_usb_win32_iso_start_frame, tvb, offset, 4, ENC_LITTLE_ENDIAN); offset += 4; num_packets = tvb_get_letohl(tvb, offset); - proto_tree_add_item(urb_tree, hf_usb_win32_iso_num_packets, tvb, offset, 4, ENC_LITTLE_ENDIAN); + num_packets_ti = proto_tree_add_item(urb_tree, hf_usb_win32_iso_num_packets, tvb, offset, 4, ENC_LITTLE_ENDIAN); offset += 4; proto_tree_add_item(urb_tree, hf_usb_win32_iso_error_count, tvb, offset, 4, ENC_LITTLE_ENDIAN); offset += 4; + if (num_packets > MAX_ISO_PACKETS) { + expert_add_info_format(pinfo, num_packets_ti, &ei_usb_bad_length, "Too many isochronous transfer packets (%u)", num_packets); + return tvb_captured_length(tvb); + } + data_start_offset = offset + 12 * num_packets; urb_tree_ti = proto_tree_get_parent(urb_tree); proto_item_set_len(urb_tree_ti, data_start_offset); @@ -6721,7 +6728,8 @@ proto_register_usb(void) { &ei_usb_desc_length_invalid, { "usb.desc_length.invalid", PI_MALFORMED, PI_ERROR, "Invalid descriptor length", EXPFILL }}, { &ei_usb_invalid_setup, { "usb.setup.invalid", PI_MALFORMED, PI_ERROR, "Only control URBs may contain a setup packet", EXPFILL }}, { &ei_usb_ss_ep_companion_before_ep, { "usb.bmAttributes.invalid_order", PI_MALFORMED, PI_ERROR, "SuperSpeed Endpoint Companion must come after Endpoint Descriptor", EXPFILL }}, - { &ei_usb_usbpcap_unknown_urb, { "usb.usbpcap.unknown_urb", PI_MALFORMED, PI_ERROR, "USBPcap did not recognize URB Function code (report to desowin.org/USBPcap)", EXPFILL }} + { &ei_usb_usbpcap_unknown_urb, { "usb.usbpcap.unknown_urb", PI_MALFORMED, PI_ERROR, "USBPcap did not recognize URB Function code (report to desowin.org/USBPcap)", EXPFILL }}, + { &ei_usb_bad_length, { "usb.bad_length", PI_MALFORMED, PI_ERROR, "Invalid length", EXPFILL }}, }; static ei_register_info ei_usbport[] = { { &ei_usbport_invalid_path_depth, { "usbport.path_depth.invalid", PI_PROTOCOL, PI_WARN, "Invalid path depth", EXPFILL }}, |