Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756558Ab3I3KZc (ORCPT ); Mon, 30 Sep 2013 06:25:32 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:43655 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755573Ab3I3KMx (ORCPT ); Mon, 30 Sep 2013 06:12:53 -0400 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Kees Cook , Jiri Kosina , Luis Henriques Subject: [PATCH 062/104] HID: validate HID report id size Date: Mon, 30 Sep 2013 11:10:39 +0100 Message-Id: <1380535881-9239-63-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.8.3.2 In-Reply-To: <1380535881-9239-1-git-send-email-luis.henriques@canonical.com> References: <1380535881-9239-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2957 Lines: 87 3.5.7.22 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Kees Cook commit 43622021d2e2b82ea03d883926605bdd0525e1d1 upstream. The "Report ID" field of a HID report is used to build indexes of reports. The kernel's index of these is limited to 256 entries, so any malicious device that sets a Report ID greater than 255 will trigger memory corruption on the host: [ 1347.156239] BUG: unable to handle kernel paging request at ffff88094958a878 [ 1347.156261] IP: [] hid_register_report+0x2a/0x8b CVE-2013-2888 Signed-off-by: Kees Cook Signed-off-by: Jiri Kosina Signed-off-by: Luis Henriques --- drivers/hid/hid-core.c | 10 +++++++--- include/linux/hid.h | 4 +++- 2 files changed, 10 insertions(+), 4 deletions(-) diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index 2f85e59..104792d 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -63,6 +63,8 @@ struct hid_report *hid_register_report(struct hid_device *device, unsigned type, struct hid_report_enum *report_enum = device->report_enum + type; struct hid_report *report; + if (id >= HID_MAX_IDS) + return NULL; if (report_enum->report_id_hash[id]) return report_enum->report_id_hash[id]; @@ -392,8 +394,10 @@ static int hid_parser_global(struct hid_parser *parser, struct hid_item *item) case HID_GLOBAL_ITEM_TAG_REPORT_ID: parser->global.report_id = item_udata(item); - if (parser->global.report_id == 0) { - hid_err(parser->device, "report_id 0 is invalid\n"); + if (parser->global.report_id == 0 || + parser->global.report_id >= HID_MAX_IDS) { + hid_err(parser->device, "report_id %u is invalid\n", + parser->global.report_id); return -1; } return 0; @@ -563,7 +567,7 @@ static void hid_close_report(struct hid_device *device) for (i = 0; i < HID_REPORT_TYPES; i++) { struct hid_report_enum *report_enum = device->report_enum + i; - for (j = 0; j < 256; j++) { + for (j = 0; j < HID_MAX_IDS; j++) { struct hid_report *report = report_enum->report_id_hash[j]; if (report) hid_free_report(report); diff --git a/include/linux/hid.h b/include/linux/hid.h index 449fa38..69b6e30 100644 --- a/include/linux/hid.h +++ b/include/linux/hid.h @@ -425,10 +425,12 @@ struct hid_report { struct hid_device *device; /* associated device */ }; +#define HID_MAX_IDS 256 + struct hid_report_enum { unsigned numbered; struct list_head report_list; - struct hid_report *report_id_hash[256]; + struct hid_report *report_id_hash[HID_MAX_IDS]; }; #define HID_REPORT_TYPES 3 -- 1.8.3.2 -- 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/