From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:36230 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751598AbdIUPDS (ORCPT ); Thu, 21 Sep 2017 11:03:18 -0400 Subject: patch "USB: core: harden cdc_parse_cdc_header" added to usb-linus To: gregkh@linuxfoundation.org, andreyknvl@google.com, stable@vger.kernel.org From: Date: Thu, 21 Sep 2017 17:03:28 +0200 Message-ID: <15060062080115@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled USB: core: harden cdc_parse_cdc_header to my usb git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git in the usb-linus branch. The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.) The patch will hopefully also be merged in Linus's tree for the next -rc kernel release. If you have any questions about this process, please let me know. >>From 2e1c42391ff2556387b3cb6308b24f6f65619feb Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Thu, 21 Sep 2017 16:58:48 +0200 Subject: USB: core: harden cdc_parse_cdc_header Andrey Konovalov reported a possible out-of-bounds problem for the cdc_parse_cdc_header function. He writes: It looks like cdc_parse_cdc_header() doesn't validate buflen before accessing buffer[1], buffer[2] and so on. The only check present is while (buflen > 0). So fix this issue up by properly validating the buffer length matches what the descriptor says it is. Reported-by: Andrey Konovalov Tested-by: Andrey Konovalov Cc: stable Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/message.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c index 4c38ea41ae96..371a07d874a3 100644 --- a/drivers/usb/core/message.c +++ b/drivers/usb/core/message.c @@ -2069,6 +2069,10 @@ int cdc_parse_cdc_header(struct usb_cdc_parsed_header *hdr, elength = 1; goto next_desc; } + if ((buflen < elength) || (elength < 3)) { + dev_err(&intf->dev, "invalid descriptor buffer length\n"); + break; + } if (buffer[1] != USB_DT_CS_INTERFACE) { dev_err(&intf->dev, "skipping garbage\n"); goto next_desc; -- 2.14.1