From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lf1-f67.google.com ([209.85.167.67]:37728 "EHLO mail-lf1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725982AbeIXNUi (ORCPT ); Mon, 24 Sep 2018 09:20:38 -0400 Received: by mail-lf1-f67.google.com with SMTP id a82-v6so347524lfa.4 for ; Mon, 24 Sep 2018 00:19:55 -0700 (PDT) From: Johan Hovold To: Greg Kroah-Hartman Cc: Johan Hovold , stable Subject: [PATCH stable-4.4] USB: serial: ti_usb_3410_5052: fix array underflow in completion handler Date: Mon, 24 Sep 2018 09:19:17 +0200 Message-Id: <20180924071917.14149-1-johan@kernel.org> In-Reply-To: <153773072566155@kroah.com> References: <153773072566155@kroah.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: commit 5dfdd24eb3d39d815bc952ae98128e967c9bba49 upstream. Similarly to a recently reported bug in io_ti, a malicious USB device could set port_number to a negative value and we would underflow the port array in the interrupt completion handler. As these devices only have one or two ports, fix this by making sure we only consider the seventh bit when determining the port number (and ignore bits 0xb0 which are typically set to 0x30). Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable Signed-off-by: Johan Hovold --- drivers/usb/serial/ti_usb_3410_5052.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/usb/serial/ti_usb_3410_5052.h b/drivers/usb/serial/ti_usb_3410_5052.h index 98f35c656c02..0cd247f75b8b 100644 --- a/drivers/usb/serial/ti_usb_3410_5052.h +++ b/drivers/usb/serial/ti_usb_3410_5052.h @@ -227,7 +227,7 @@ struct ti_interrupt { } __attribute__((packed)); /* Interrupt codes */ -#define TI_GET_PORT_FROM_CODE(c) (((c) >> 4) - 3) +#define TI_GET_PORT_FROM_CODE(c) (((c) >> 6) & 0x01) #define TI_GET_FUNC_FROM_CODE(c) ((c) & 0x0f) #define TI_CODE_HARDWARE_ERROR 0xFF #define TI_CODE_DATA_ERROR 0x03 -- 2.19.0