From patchwork Mon Aug 10 15:21:29 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 266680 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=-13.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, 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 937F1C433DF for ; Mon, 10 Aug 2020 15:27:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5F83822B47 for ; Mon, 10 Aug 2020 15:27:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597073269; bh=Xr/LrSwoPkpO+b5GNnU8G45cuP+w+tgscd35PT6++AU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=fsRkXOmKDGwZNWjjGwaebfw1EwthY4HAvaLa6YowpTzCe/bOa3Hh4DVcYTTzgsRIR prMWNdJp3DFx5SmEX10sCmC8ffjzUDPhLFsK7VmTUrkSnsVzWH6GizH0HFXyreTxve w/jVuwNg41HaCQPZf0bCArnWdzUbn8V9EDM2IFF4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728265AbgHJP1q (ORCPT ); Mon, 10 Aug 2020 11:27:46 -0400 Received: from mail.kernel.org ([198.145.29.99]:33666 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728786AbgHJP1m (ORCPT ); Mon, 10 Aug 2020 11:27:42 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (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 DBE9322D08; Mon, 10 Aug 2020 15:27:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597073261; bh=Xr/LrSwoPkpO+b5GNnU8G45cuP+w+tgscd35PT6++AU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VwOEFHtMWKKOlLVyDBFCcmWqauRC6P/5/6Gd36s66RxhwsOyiRYt9keIg+WNUoBLU qUIR3JZsFQvjbYlUmpjfd72LVElCOBtNPezY6Bma4ZlOLPGwhBXBENdQj2pzKbSuiH ERPYBtTRRmb44e/8KAPqURd84oViYLaOdhA3zyY0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Julian Squires , Johannes Berg , Sasha Levin Subject: [PATCH 5.4 42/67] cfg80211: check vendor command doit pointer before use Date: Mon, 10 Aug 2020 17:21:29 +0200 Message-Id: <20200810151811.514485826@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200810151809.438685785@linuxfoundation.org> References: <20200810151809.438685785@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Julian Squires [ Upstream commit 4052d3d2e8f47a15053320bbcbe365d15610437d ] In the case where a vendor command does not implement doit, and has no flags set, doit would not be validated and a NULL pointer dereference would occur, for example when invoking the vendor command via iw. I encountered this while developing new vendor commands. Perhaps in practice it is advisable to always implement doit along with dumpit, but it seems reasonable to me to always check doit anyway, not just when NEED_WDEV. Signed-off-by: Julian Squires Link: https://lore.kernel.org/r/20200706211353.2366470-1-julian@cipht.net Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin --- net/wireless/nl80211.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index a34bbca80f498..ec559dbad56ea 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -12949,13 +12949,13 @@ static int nl80211_vendor_cmd(struct sk_buff *skb, struct genl_info *info) if (!wdev_running(wdev)) return -ENETDOWN; } - - if (!vcmd->doit) - return -EOPNOTSUPP; } else { wdev = NULL; } + if (!vcmd->doit) + return -EOPNOTSUPP; + if (info->attrs[NL80211_ATTR_VENDOR_DATA]) { data = nla_data(info->attrs[NL80211_ATTR_VENDOR_DATA]); len = nla_len(info->attrs[NL80211_ATTR_VENDOR_DATA]);