Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752668AbdFSTkW (ORCPT + 2 others); Mon, 19 Jun 2017 15:40:22 -0400 Received: from wtarreau.pck.nerim.net ([62.212.114.60]:51780 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752147AbdFSSeM (ORCPT ); Mon, 19 Jun 2017 14:34:12 -0400 From: Willy Tarreau To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, linux@roeck-us.net Cc: Greg Kroah-Hartman , Felipe Balbi , Willy Tarreau Subject: [PATCH 3.10 044/268] usb: gadgetfs: restrict upper bound on device configuration size Date: Mon, 19 Jun 2017 20:29:03 +0200 Message-Id: <1497897167-14556-45-git-send-email-w@1wt.eu> X-Mailer: git-send-email 2.8.0.rc2.1.gbe9624a In-Reply-To: <1497897167-14556-1-git-send-email-w@1wt.eu> References: <1497897167-14556-1-git-send-email-w@1wt.eu> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: From: Greg Kroah-Hartman commit 0994b0a257557e18ee8f0b7c5f0f73fe2b54eec1 upstream. Andrey Konovalov reported that we were not properly checking the upper limit before of a device configuration size before calling memdup_user(), which could cause some problems. So set the upper limit to PAGE_SIZE * 4, which should be good enough for all devices. Reported-by: Andrey Konovalov Signed-off-by: Felipe Balbi Signed-off-by: Willy Tarreau --- drivers/usb/gadget/inode.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/usb/gadget/inode.c b/drivers/usb/gadget/inode.c index 42a3090..5b45429 100644 --- a/drivers/usb/gadget/inode.c +++ b/drivers/usb/gadget/inode.c @@ -1854,7 +1854,8 @@ dev_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr) u32 tag; char *kbuf; - if (len < (USB_DT_CONFIG_SIZE + USB_DT_DEVICE_SIZE + 4)) + if ((len < (USB_DT_CONFIG_SIZE + USB_DT_DEVICE_SIZE + 4)) || + (len > PAGE_SIZE * 4)) return -EINVAL; /* we might need to change message format someday */ -- 2.8.0.rc2.1.gbe9624a