From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 45B92C64EB5 for ; Tue, 2 Oct 2018 13:28:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0CF152089A for ; Tue, 2 Oct 2018 13:28:05 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0CF152089A Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729006AbeJBULY (ORCPT ); Tue, 2 Oct 2018 16:11:24 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:60684 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727658AbeJBULX (ORCPT ); Tue, 2 Oct 2018 16:11:23 -0400 Received: from localhost (24-104-73-23-ip-static.hfc.comcastbusiness.net [24.104.73.23]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id 3E485266; Tue, 2 Oct 2018 13:28:02 +0000 (UTC) From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dan Carpenter , Kalle Valo , Sasha Levin Subject: [PATCH 4.18 089/228] rndis_wlan: potential buffer overflow in rndis_wlan_auth_indication() Date: Tue, 2 Oct 2018 06:23:06 -0700 Message-Id: <20181002132505.353175538@linuxfoundation.org> X-Mailer: git-send-email 2.19.0 In-Reply-To: <20181002132459.032960735@linuxfoundation.org> References: <20181002132459.032960735@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dan Carpenter [ Upstream commit ae636fb1554833ee5133ca47bf4b2791b6739c52 ] This is a static checker fix, not something I have tested. The issue is that on the second iteration through the loop, we jump forward by le32_to_cpu(auth_req->length) bytes. The problem is that if the length is more than "buflen" then we end up with a negative "buflen". A negative buflen is type promoted to a high positive value and the loop continues but it's accessing beyond the end of the buffer. I believe the "auth_req->length" comes from the firmware and if the firmware is malicious or buggy, you're already toasted so the impact of this bug is probably not very severe. Fixes: 030645aceb3d ("rndis_wlan: handle 802.11 indications from device") Signed-off-by: Dan Carpenter Signed-off-by: Kalle Valo Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/net/wireless/rndis_wlan.c | 2 ++ 1 file changed, 2 insertions(+) --- a/drivers/net/wireless/rndis_wlan.c +++ b/drivers/net/wireless/rndis_wlan.c @@ -2928,6 +2928,8 @@ static void rndis_wlan_auth_indication(s while (buflen >= sizeof(*auth_req)) { auth_req = (void *)buf; + if (buflen < le32_to_cpu(auth_req->length)) + return; type = "unknown"; flags = le32_to_cpu(auth_req->flags); pairwise_error = false;