From patchwork Mon Aug 10 15:21:07 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 266693 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 CF751C433DF for ; Mon, 10 Aug 2020 15:24:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9AB7122CA1 for ; Mon, 10 Aug 2020 15:24:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597073049; bh=0QbxLggjBKO58eoG4bJ9frg+oeij7hDqcORloJgxLIc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=nHjKmT4+JtTydQ++tmVytkNHoIe4qKtxv6cKdqD/BUuG+eOyE2pwobV9+DIQSaV4Z pOWSElaZcGTCzb2qHwlK+HAVtgtxBNiWYTBjDuGh5eYe/ISuvKJCUbpcIDV6EJ6YdN LgZW/RpHqvjORUtXYcsUFlcdrcT9dSFJXCxhKUJk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728144AbgHJPYH (ORCPT ); Mon, 10 Aug 2020 11:24:07 -0400 Received: from mail.kernel.org ([198.145.29.99]:56700 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727877AbgHJPYG (ORCPT ); Mon, 10 Aug 2020 11:24:06 -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 2276922BEA; Mon, 10 Aug 2020 15:24:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597073045; bh=0QbxLggjBKO58eoG4bJ9frg+oeij7hDqcORloJgxLIc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Y8BXiyGua1+WPPqqK7hPuwsRC79S7adDpra4YQWL0NNzzTGP05QViCWxoi9IR2hcv D71kRS2nEqu8wATcA0UjQzyuIaWYcTtBB7U4fnWSagAFVRcMPPM9+zoYYEiNFVIt1+ 01Xcsbwif7qAW42hd5PYSzi7AXtRpPDEZ0gaiais= 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 5.7 48/79] cfg80211: check vendor command doit pointer before use Date: Mon, 10 Aug 2020 17:21:07 +0200 Message-Id: <20200810151814.637692808@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200810151812.114485777@linuxfoundation.org> References: <20200810151812.114485777@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 7ae6b90e0d264..970f05c4150ea 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -13190,13 +13190,13 @@ 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]);