Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757747Ab3JJPu4 (ORCPT ); Thu, 10 Oct 2013 11:50:56 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:53104 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757724Ab3JJPuw (ORCPT ); Thu, 10 Oct 2013 11:50:52 -0400 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Benjamin Tissoires , Jiri Kosina , Kamal Mostafa Subject: [PATCH 041/104] HID: validate feature and input report details Date: Thu, 10 Oct 2013 08:41:29 -0700 Message-Id: <1381419752-29733-42-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.8.1.2 In-Reply-To: <1381419752-29733-1-git-send-email-kamal@canonical.com> References: <1381419752-29733-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5116 Lines: 144 3.8.13.11 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Benjamin Tissoires commit cc6b54aa54bf40b762cab45a9fc8aa81653146eb upstream. When dealing with usage_index, be sure to properly use unsigned instead of int to avoid overflows. When working on report fields, always validate that their report_counts are in bounds. Without this, a HID device could report a malicious feature report that could trick the driver into a heap overflow: [ 634.885003] usb 1-1: New USB device found, idVendor=0596, idProduct=0500 ... [ 676.469629] BUG kmalloc-192 (Tainted: G W ): Redzone overwritten CVE-2013-2897 Signed-off-by: Benjamin Tissoires Acked-by: Kees Cook Signed-off-by: Jiri Kosina Signed-off-by: Kamal Mostafa --- drivers/hid/hid-core.c | 16 +++++++--------- drivers/hid/hid-input.c | 11 ++++++++++- 2 files changed, 17 insertions(+), 10 deletions(-) diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index bf31892..14744e0 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -94,7 +94,6 @@ EXPORT_SYMBOL_GPL(hid_register_report); static struct hid_field *hid_register_field(struct hid_report *report, unsigned usages, unsigned values) { struct hid_field *field; - int i; if (report->maxfield == HID_MAX_FIELDS) { hid_err(report->device, "too many fields in report\n"); @@ -113,9 +112,6 @@ static struct hid_field *hid_register_field(struct hid_report *report, unsigned field->value = (s32 *)(field->usage + usages); field->report = report; - for (i = 0; i < usages; i++) - field->usage[i].usage_index = i; - return field; } @@ -226,9 +222,9 @@ static int hid_add_field(struct hid_parser *parser, unsigned report_type, unsign { struct hid_report *report; struct hid_field *field; - int usages; + unsigned usages; unsigned offset; - int i; + unsigned i; report = hid_register_report(parser->device, report_type, parser->global.report_id); if (!report) { @@ -255,7 +251,8 @@ static int hid_add_field(struct hid_parser *parser, unsigned report_type, unsign if (!parser->local.usage_index) /* Ignore padding fields */ return 0; - usages = max_t(int, parser->local.usage_index, parser->global.report_count); + usages = max_t(unsigned, parser->local.usage_index, + parser->global.report_count); field = hid_register_field(report, usages, parser->global.report_count); if (!field) @@ -266,13 +263,14 @@ static int hid_add_field(struct hid_parser *parser, unsigned report_type, unsign field->application = hid_lookup_collection(parser, HID_COLLECTION_APPLICATION); for (i = 0; i < usages; i++) { - int j = i; + unsigned j = i; /* Duplicate the last usage we parsed if we have excess values */ if (i >= parser->local.usage_index) j = parser->local.usage_index - 1; field->usage[i].hid = parser->local.usage[j]; field->usage[i].collection_index = parser->local.collection_index[j]; + field->usage[i].usage_index = i; } field->maxusage = usages; @@ -1295,7 +1293,7 @@ int hid_report_raw_event(struct hid_device *hid, int type, u8 *data, int size, goto out; } - if (hid->claimed != HID_CLAIMED_HIDRAW) { + if (hid->claimed != HID_CLAIMED_HIDRAW && report->maxfield) { for (a = 0; a < report->maxfield; a++) hid_input_field(hid, report->field[a], cdata, interrupt); } diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c index f495ada..50487c2 100644 --- a/drivers/hid/hid-input.c +++ b/drivers/hid/hid-input.c @@ -484,6 +484,10 @@ static void hidinput_configure_usage(struct hid_input *hidinput, struct hid_fiel if (field->flags & HID_MAIN_ITEM_CONSTANT) goto ignore; + /* Ignore if report count is out of bounds. */ + if (field->report_count < 1) + goto ignore; + /* only LED usages are supported in output fields */ if (field->report_type == HID_OUTPUT_REPORT && (usage->hid & HID_USAGE_PAGE) != HID_UP_LED) { @@ -1162,7 +1166,11 @@ static void report_features(struct hid_device *hid) rep_enum = &hid->report_enum[HID_FEATURE_REPORT]; list_for_each_entry(rep, &rep_enum->report_list, list) - for (i = 0; i < rep->maxfield; i++) + for (i = 0; i < rep->maxfield; i++) { + /* Ignore if report count is out of bounds. */ + if (rep->field[i]->report_count < 1) + continue; + for (j = 0; j < rep->field[i]->maxusage; j++) { /* Verify if Battery Strength feature is available */ hidinput_setup_battery(hid, HID_FEATURE_REPORT, rep->field[i]); @@ -1171,6 +1179,7 @@ static void report_features(struct hid_device *hid) drv->feature_mapping(hid, rep->field[i], rep->field[i]->usage + j); } + } } static struct hid_input *hidinput_allocate(struct hid_device *hid) -- 1.8.1.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/