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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 542F6C4332F for ; Thu, 13 Oct 2022 18:24:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230418AbiJMSYE (ORCPT ); Thu, 13 Oct 2022 14:24:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47600 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231386AbiJMSXF (ORCPT ); Thu, 13 Oct 2022 14:23:05 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 48EBF4C012; Thu, 13 Oct 2022 11:18:45 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 78B0A61913; Thu, 13 Oct 2022 17:56:53 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9A99DC433D6; Thu, 13 Oct 2022 17:56:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1665683812; bh=7ADSkhJgMzgbvEfxkGhKSmMII+dlmQ0WYUlz4phgh+4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SB/AhnBpl4/DZKrMWfNremN16h91J348QFJWGue3xGDqUTmUUPB6fffPhVlhoqt/h yS2U4Uro9v/gw8HJaJMIQRaze9F5q/P7PdWLgOV9ydcXJ4wKdfPl+a+Tma75fvuCrY rPHlpBn++pERgefEVpZuppYEWlucmytqZ8/jGJMI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Soenke Huster , Johannes Berg Subject: [PATCH 5.10 45/54] wifi: cfg80211: ensure length byte is present before access Date: Thu, 13 Oct 2022 19:52:39 +0200 Message-Id: <20221013175148.431764542@linuxfoundation.org> X-Mailer: git-send-email 2.38.0 In-Reply-To: <20221013175147.337501757@linuxfoundation.org> References: <20221013175147.337501757@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Johannes Berg commit 567e14e39e8f8c6997a1378bc3be615afca86063 upstream. When iterating the elements here, ensure the length byte is present before checking it to see if the entire element will fit into the buffer. Longer term, we should rewrite this code using the type-safe element iteration macros that check all of this. Fixes: 0b8fb8235be8 ("cfg80211: Parsing of Multiple BSSID information in scanning") Reported-by: Soenke Huster Signed-off-by: Johannes Berg Signed-off-by: Greg Kroah-Hartman --- net/wireless/scan.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/net/wireless/scan.c +++ b/net/wireless/scan.c @@ -304,7 +304,8 @@ static size_t cfg80211_gen_new_ie(const tmp_old = cfg80211_find_ie(WLAN_EID_SSID, ie, ielen); tmp_old = (tmp_old) ? tmp_old + tmp_old[1] + 2 : ie; - while (tmp_old + tmp_old[1] + 2 - ie <= ielen) { + while (tmp_old + 2 - ie <= ielen && + tmp_old + tmp_old[1] + 2 - ie <= ielen) { if (tmp_old[0] == 0) { tmp_old++; continue; @@ -364,7 +365,8 @@ static size_t cfg80211_gen_new_ie(const * copied to new ie, skip ssid, capability, bssid-index ie */ tmp_new = sub_copy; - while (tmp_new + tmp_new[1] + 2 - sub_copy <= subie_len) { + while (tmp_new + 2 - sub_copy <= subie_len && + tmp_new + tmp_new[1] + 2 - sub_copy <= subie_len) { if (!(tmp_new[0] == WLAN_EID_NON_TX_BSSID_CAP || tmp_new[0] == WLAN_EID_SSID)) { memcpy(pos, tmp_new, tmp_new[1] + 2);