Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753945AbaBEUDs (ORCPT ); Wed, 5 Feb 2014 15:03:48 -0500 Received: from mail.windriver.com ([147.11.1.11]:54203 "EHLO mail.windriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753708AbaBEUDk (ORCPT ); Wed, 5 Feb 2014 15:03:40 -0500 From: Paul Gortmaker To: , CC: Kees Cook , Jiri Kosina , Paul Gortmaker Subject: [v2.6.34-stable 017/213] HID: validate HID report id size Date: Wed, 5 Feb 2014 14:59:32 -0500 Message-ID: <1391630568-49251-18-git-send-email-paul.gortmaker@windriver.com> X-Mailer: git-send-email 1.8.5.2 In-Reply-To: <1391630568-49251-1-git-send-email-paul.gortmaker@windriver.com> References: <1391630568-49251-1-git-send-email-paul.gortmaker@windriver.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Kees Cook ------------------- This is a commit scheduled for the next v2.6.34 longterm release. http://git.kernel.org/?p=linux/kernel/git/paulg/longterm-queue-2.6.34.git If you see a problem with using this for longterm, please comment. ------------------- 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 [PG: hid_err() --> dbg_hid() in 2.6.34 baseline] Signed-off-by: Paul Gortmaker --- 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 07ddda553a95..195e366ea18d 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -56,6 +56,8 @@ 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]; @@ -367,8 +369,10 @@ 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) { - dbg_hid("report_id 0 is invalid\n"); + if (parser->global.report_id == 0 || + parser->global.report_id >= HID_MAX_IDS) { + dbg_hid("report_id %u is invalid\n", + parser->global.report_id); return -1; } return 0; @@ -545,7 +549,7 @@ static void hid_device_release(struct device *dev) 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 b1344ec4b7fc..85e0942cfd76 100644 --- a/include/linux/hid.h +++ b/include/linux/hid.h @@ -410,10 +410,12 @@ 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 -- 1.8.5.2 -- 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/