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=-12.8 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,USER_AGENT_GIT autolearn=unavailable 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 28DF9C433DF for ; Thu, 20 Aug 2020 10:32:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D816E20658 for ; Thu, 20 Aug 2020 10:32:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597919561; bh=8aQaJQ3yhJZ2jljzx1rQZ4agQxGWLhV6PGFPiR1F+N8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=rycDVyOdaJ3JNvQT7X2yzjcNSVIFtm3uQVlu3FSSDGgsLfzD9IO1dupDtZG/wFP46 arJU7W2uGjXOl+R7LqaaWQOl4ULRGnv68M+LjsPL/EmCMt4qcHIZ+CNxxHuCi3pHno 5eUaYFkL0nrPpmOIJH9bHOskJszK+FuEdNcr/ELI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731867AbgHTKcj (ORCPT ); Thu, 20 Aug 2020 06:32:39 -0400 Received: from mail.kernel.org ([198.145.29.99]:44586 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728833AbgHTKUE (ORCPT ); Thu, 20 Aug 2020 06:20:04 -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 EA54320738; Thu, 20 Aug 2020 10:20:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597918801; bh=8aQaJQ3yhJZ2jljzx1rQZ4agQxGWLhV6PGFPiR1F+N8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WMsg9StSFvX1bhYs1EQ+LV+vmo4p+nKF+GkPhobBrOQG4oj/Z3JbG1HatqiNOGy/v JfTqq2lDcP8W2Jb4IjKIIgC0S+BR2Ou1BgIAgA5I0MkOlgofheKeew6WIQPHlS5Vbc 3urcuG+7wew/rEU1g2rza5mkMoyNGB5+7epxptV8= 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 4.4 042/149] cfg80211: check vendor command doit pointer before use Date: Thu, 20 Aug 2020 11:21:59 +0200 Message-Id: <20200820092127.773758336@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200820092125.688850368@linuxfoundation.org> References: <20200820092125.688850368@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: 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 c6c168f20b0f2..55de35c4434a8 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -10180,13 +10180,13 @@ static int nl80211_vendor_cmd(struct sk_buff *skb, struct genl_info *info) if (!wdev->netdev && !wdev->p2p_started) 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]); -- 2.25.1