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 B38F0CA9EAF for ; Sun, 27 Oct 2019 21:11:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8388C214E0 for ; Sun, 27 Oct 2019 21:11:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572210676; bh=FmXQsAMYoRFFNGFa1iTYEpJCv+dMzOYBi8XUuX6CirQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=niTCIOJvgIdJETmDWHJThstCiGiUP6Q/iR3DKCA1bikUS/m4EMj596GOxIJ3hl4ri KR/2bwGuzKXUCIYQA/VcfS9cz0VTuVFZ4kmq47SfkDx1NOIHfQizwLWzuuajvKSWDn dyQlT+B+YEwHqelprr6tCoQAGbIHxPrT9yB3ysAc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727899AbfJ0VLP (ORCPT ); Sun, 27 Oct 2019 17:11:15 -0400 Received: from mail.kernel.org ([198.145.29.99]:57736 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729860AbfJ0VLO (ORCPT ); Sun, 27 Oct 2019 17:11:14 -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 61E8F20B7C; Sun, 27 Oct 2019 21:11:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572210673; bh=FmXQsAMYoRFFNGFa1iTYEpJCv+dMzOYBi8XUuX6CirQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=0rhjx1nAaLnHwDi5AeQ+0QIWS+NjKLPJREzEN19ybiwTBIAH4JZAnenrVzCzcF7th GUth281OBsSjTOaESujmzpl1COIsU7PhTEtOB82S6ixfNUAFiR7zcmCmchfhkF9oKl Bawrpr3jAo2Qi26kCYpyY8h4SIi6LJDFCfuCEDZI= 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 4.14 095/119] mac80211: Reject malformed SSID elements Date: Sun, 27 Oct 2019 22:01:12 +0100 Message-Id: <20191027203348.650128093@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: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Will Deacon commit 4152561f5da3fca92af7179dd538ea89e248f9d0 upstream. Although this shouldn't occur in practice, it's a good idea to bounds check the length field of the SSID element prior to using it for things like allocations or memcpy operations. Cc: Cc: Kees Cook Reported-by: Nicolas Waisman Signed-off-by: Will Deacon Link: https://lore.kernel.org/r/20191004095132.15777-1-will@kernel.org Signed-off-by: Johannes Berg Signed-off-by: Greg Kroah-Hartman --- net/mac80211/mlme.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- a/net/mac80211/mlme.c +++ b/net/mac80211/mlme.c @@ -2430,7 +2430,8 @@ struct sk_buff *ieee80211_ap_probereq_ge rcu_read_lock(); ssid = ieee80211_bss_get_ie(cbss, WLAN_EID_SSID); - if (WARN_ON_ONCE(ssid == NULL)) + if (WARN_ONCE(!ssid || ssid[1] > IEEE80211_MAX_SSID_LEN, + "invalid SSID element (len=%d)", ssid ? ssid[1] : -1)) ssid_len = 0; else ssid_len = ssid[1]; @@ -4756,7 +4757,7 @@ int ieee80211_mgd_assoc(struct ieee80211 rcu_read_lock(); ssidie = ieee80211_bss_get_ie(req->bss, WLAN_EID_SSID); - if (!ssidie) { + if (!ssidie || ssidie[1] > sizeof(assoc_data->ssid)) { rcu_read_unlock(); kfree(assoc_data); return -EINVAL;