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=-15.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 1E8F8C433E0 for ; Fri, 26 Feb 2021 12:07:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C553C64ED2 for ; Fri, 26 Feb 2021 12:07:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230060AbhBZMHc (ORCPT ); Fri, 26 Feb 2021 07:07:32 -0500 Received: from mail.kernel.org ([198.145.29.99]:54530 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229550AbhBZMHa (ORCPT ); Fri, 26 Feb 2021 07:07:30 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 31B4864E85; Fri, 26 Feb 2021 12:06:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1614341209; bh=qRTRg+Ld1JvWeMc0olIaD6Tm+zb/5qtWSSfoEhnQEC0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=OvGNyIN4O2RQfLtsNLJNBpTtgzJmKKoCEooXcKepz4kiyHOoLUziEn22HCgGiN0nP i3pTPTXpw2lVDZcOIebficIYrr1MUCf9QBzfiAcNj2IK7Qj5KSXs4nLCvngCPbsox4 RdpxlHQh7K/n0uAjto/Or+M7Y5PUw5pcgBeqZA/s= Date: Fri, 26 Feb 2021 13:06:46 +0100 From: Greg KH To: Lee Gibson Cc: devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] staging: rtl8192e: Fix possible buffer overflow in _rtl92e_wx_set_scan Message-ID: References: <20210226114829.316980-1-leegib@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210226114829.316980-1-leegib@gmail.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Feb 26, 2021 at 11:48:29AM +0000, Lee Gibson wrote: > Function _rtl92e_wx_set_scan calls memcpy without checking the length. > A user could control that length and trigger a buffer overflow. > Fix by checking the length is within the maximum allowed size. > > Signed-off-by: Lee Gibson > --- > drivers/staging/rtl8192e/rtl8192e/rtl_wx.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/staging/rtl8192e/rtl8192e/rtl_wx.c b/drivers/staging/rtl8192e/rtl8192e/rtl_wx.c > index 16bcee13f64b..2acc4f314732 100644 > --- a/drivers/staging/rtl8192e/rtl8192e/rtl_wx.c > +++ b/drivers/staging/rtl8192e/rtl8192e/rtl_wx.c > @@ -406,6 +406,9 @@ static int _rtl92e_wx_set_scan(struct net_device *dev, > struct iw_scan_req *req = (struct iw_scan_req *)b; > > if (req->essid_len) { > + if (req->essid_len > IW_ESSID_MAX_SIZE) > + req->essid_len = IW_ESSID_MAX_SIZE; > + How about using the "pattern" the other wireless drivers use of: int len = min((int)req->essid_len, IW_ESSID_MAX_SIZE); instead? thanks, greg k-h