Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755209Ab3IYAIm (ORCPT ); Tue, 24 Sep 2013 20:08:42 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:38453 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754985Ab3IYAIS (ORCPT ); Tue, 24 Sep 2013 20:08:18 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Kees Cook , Jiri Kosina Subject: [ 19/28] HID: validate HID report id size Date: Tue, 24 Sep 2013 17:07:50 -0700 Message-Id: <20130925000653.019753635@linuxfoundation.org> X-Mailer: git-send-email 1.8.4.3.gca3854a In-Reply-To: <20130925000648.404447782@linuxfoundation.org> References: <20130925000648.404447782@linuxfoundation.org> User-Agent: quilt/0.60-5.1.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2682 Lines: 85 3.0-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: Greg Kroah-Hartman --- drivers/hid/hid-core.c | 12 ++++++++---- include/linux/hid.h | 4 +++- 2 files changed, 11 insertions(+), 5 deletions(-) --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -58,6 +58,8 @@ struct hid_report *hid_register_report(s 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]; @@ -379,9 +381,11 @@ static int hid_parser_global(struct hid_ 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"); - return -1; + 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; @@ -551,7 +555,7 @@ static void hid_device_release(struct de 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); --- a/include/linux/hid.h +++ b/include/linux/hid.h @@ -414,10 +414,12 @@ 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 -- 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/