From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kees Cook Subject: [PATCH 6/7] HID: lenovo-tpkbd: validate output report details Date: Wed, 4 Sep 2013 09:37:24 -0700 Message-ID: <1378312645-27736-7-git-send-email-keescook@chromium.org> References: <1378312645-27736-1-git-send-email-keescook@chromium.org> Return-path: Received: from smtp.outflux.net ([198.145.64.163]:39559 "EHLO smtp.outflux.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964880Ab3IDQhn (ORCPT ); Wed, 4 Sep 2013 12:37:43 -0400 In-Reply-To: <1378312645-27736-1-git-send-email-keescook@chromium.org> Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: linux-input@vger.kernel.org Cc: Benjamin Tissoires , Jiri Kosina , Henrik Rydberg , Kees Cook , stable@kernel.org A HID device could send a malicious output report that would cause the lenovo-tpkbd HID driver to write just beyond the output report allocation during initialization, causing a heap overflow: [ 76.109807] usb 1-1: New USB device found, idVendor=17ef, idProduct=6009 ... [ 80.462540] BUG kmalloc-192 (Tainted: G W ): Redzone overwritten CVE-2013-2894 Signed-off-by: Kees Cook Cc: stable@kernel.org --- drivers/hid/hid-lenovo-tpkbd.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/drivers/hid/hid-lenovo-tpkbd.c b/drivers/hid/hid-lenovo-tpkbd.c index 07837f5..f458e76 100644 --- a/drivers/hid/hid-lenovo-tpkbd.c +++ b/drivers/hid/hid-lenovo-tpkbd.c @@ -339,7 +339,15 @@ static int tpkbd_probe_tp(struct hid_device *hdev) struct tpkbd_data_pointer *data_pointer; size_t name_sz = strlen(dev_name(dev)) + 16; char *name_mute, *name_micmute; - int ret; + int i, ret; + + /* Validate required reports. */ + for (i = 0; i < 4; i++) { + if (!hid_validate_values(hdev, HID_OUTPUT_REPORT, 4, i, 1)) + return -ENODEV; + } + if (!hid_validate_values(hdev, HID_OUTPUT_REPORT, 3, 0, 2)) + return -ENODEV; if (sysfs_create_group(&hdev->dev.kobj, &tpkbd_attr_group_pointer)) { -- 1.7.9.5