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 20E26CA9EBC for ; Sun, 27 Oct 2019 21:15:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E46F1214E0 for ; Sun, 27 Oct 2019 21:15:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572210912; bh=kzLgkatN03oAoSCm0PyuozQvym8DkEP2IAbCKiizFyw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=tvOmpP+by6pKm2iNvsimEqwbmH+fcSci3MdSydojBICe79C6cGoL2DJpg6puKva/H M8WNsRD34sHyQlVxK2LogL+u+LmE4UC7aIlE22AHxOsHJ1Y9XvELdBCpK6BbMrJWtJ 8DEvNWMyQ1U0mfMrua7O/F7rwHdPcMdvIEsRF95E= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730604AbfJ0VPK (ORCPT ); Sun, 27 Oct 2019 17:15:10 -0400 Received: from mail.kernel.org ([198.145.29.99]:34348 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729353AbfJ0VPK (ORCPT ); Sun, 27 Oct 2019 17:15:10 -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 E633B214E0; Sun, 27 Oct 2019 21:15:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572210909; bh=kzLgkatN03oAoSCm0PyuozQvym8DkEP2IAbCKiizFyw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=mzIGOp/p/zPrG/IGMs3h7CYa7/exZalyXxQdW54YQnX1vcxFyskWcu6ypm+dAjHKQ 8xWBMMnWwYWfA7ph9r8klfTRWCpyQd6vptYJ8TB+VKAA7USCG5hWQGZgTG5ejQ15Ty ckq7dLrEVBSE2IRgon0O0vhqB1Vn1643O9uGJUKg= 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 4.19 58/93] mac80211: Reject malformed SSID elements Date: Sun, 27 Oct 2019 22:01:10 +0100 Message-Id: <20191027203303.292196375@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191027203251.029297948@linuxfoundation.org> References: <20191027203251.029297948@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 @@ -2554,7 +2554,8 @@ 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]; @@ -5039,7 +5040,7 @@ 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;