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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,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 A8DD5CA9EAF for ; Sun, 27 Oct 2019 21:34:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7BA0F20717 for ; Sun, 27 Oct 2019 21:34:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572212061; bh=G8fdBiczYjP1dj+XAo4W0fgeejN6M3is5d/XqM9NW8A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=PUbwQ0mw9hGQZJMfzxXycaic8IEEQoyl2we9mK7EZJcVzPMA5OdaJkUOGWTvcQMHL tT3B2GDPKyc03jhB2XXOWKBer6n/kMAH8fH/jNjqkBb5hibjxO1H4OD8txfk/JXtOf VGyWW2MiHNBly/6pQgzDrm2UD9eoOEa8dvj5cDhs= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732588AbfJ0VeU (ORCPT ); Sun, 27 Oct 2019 17:34:20 -0400 Received: from mail.kernel.org ([198.145.29.99]:57702 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729848AbfJ0VLL (ORCPT ); Sun, 27 Oct 2019 17:11:11 -0400 Received: from localhost (100.50.158.77.rev.sfr.net [77.158.50.100]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 8D3AF21848; Sun, 27 Oct 2019 21:11:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572210671; bh=G8fdBiczYjP1dj+XAo4W0fgeejN6M3is5d/XqM9NW8A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rkg8Ctn/yfpSanX5+0UrZ6qI6KmSFCqSW5FpmootWeb03+dq1KS8GCjHfgOLG3UhT V0xYWs+F5URIUVmuYLKL7EITIF6r4aGv0oqjJyLUbx726wxtlwM4XbsvB3c0XofpH/ P40rx7qeyuaH4Nh9mYctPy7wsa1svt2bqaOHjY7g= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Kees Cook , Nicolas Waisman , Will Deacon , Johannes Berg Subject: [PATCH 4.14 094/119] cfg80211: wext: avoid copying malformed SSIDs Date: Sun, 27 Oct 2019 22:01:11 +0100 Message-Id: <20191027203348.587555174@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191027203259.948006506@linuxfoundation.org> References: <20191027203259.948006506@linuxfoundation.org> User-Agent: quilt/0.66 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 From: Will Deacon commit 4ac2813cc867ae563a1ba5a9414bfb554e5796fa upstream. Ensure the SSID element is bounds-checked prior to invoking memcpy() with its length field, when copying to userspace. Cc: Cc: Kees Cook Reported-by: Nicolas Waisman Signed-off-by: Will Deacon Link: https://lore.kernel.org/r/20191004095132.15777-2-will@kernel.org [adjust commit log a bit] Signed-off-by: Johannes Berg Signed-off-by: Greg Kroah-Hartman --- net/wireless/wext-sme.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) --- a/net/wireless/wext-sme.c +++ b/net/wireless/wext-sme.c @@ -202,6 +202,7 @@ int cfg80211_mgd_wext_giwessid(struct ne struct iw_point *data, char *ssid) { struct wireless_dev *wdev = dev->ieee80211_ptr; + int ret = 0; /* call only for station! */ if (WARN_ON(wdev->iftype != NL80211_IFTYPE_STATION)) @@ -219,7 +220,10 @@ int cfg80211_mgd_wext_giwessid(struct ne if (ie) { data->flags = 1; data->length = ie[1]; - memcpy(ssid, ie + 2, data->length); + if (data->length > IW_ESSID_MAX_SIZE) + ret = -EINVAL; + else + memcpy(ssid, ie + 2, data->length); } rcu_read_unlock(); } else if (wdev->wext.connect.ssid && wdev->wext.connect.ssid_len) { @@ -229,7 +233,7 @@ int cfg80211_mgd_wext_giwessid(struct ne } wdev_unlock(wdev); - return 0; + return ret; } int cfg80211_mgd_wext_siwap(struct net_device *dev,