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=-9.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 88671CA9ED1 for ; Sun, 3 Nov 2019 03:14:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6027A21726 for ; Sun, 3 Nov 2019 03:14:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="FM8f0Lnv" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727452AbfKCDNi (ORCPT ); Sat, 2 Nov 2019 23:13:38 -0400 Received: from mail-wm1-f67.google.com ([209.85.128.67]:37869 "EHLO mail-wm1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727366AbfKCDNh (ORCPT ); Sat, 2 Nov 2019 23:13:37 -0400 Received: by mail-wm1-f67.google.com with SMTP id q130so12628867wme.2; Sat, 02 Nov 2019 20:13:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id; bh=1kt8Pfq43g42ZTuGel3KWUrOcZMTLFPWxdZ8oxo4qCo=; b=FM8f0LnvjmH/XGjLXTFQiiWB/EtzR9p2kaOHqiNKAzqY8dcMMqZpUa6DT+J+JQfvkU SgOYuHSZzbun2RSKqhOK2WR+jy8BNyNDQg/+rcmWnv6j6djzef74vGPYW/ZDCCyg2Lr5 V+kVG/3G9O5gtVcVLspvqb6t+8S+a4NXGkR77eZj0CCOgTOs/EFkReWTc+hud5VxfGcV bMbV1HkEcFkBJ+IQ9K5W9CgDf0xiQ8KWLmAMq4tSvExI16txiq2ljLe5nV21kTrM7NaF C0eU+LjtcRzlvuuOEvji7gEGr3GbWw5BsWGxiJrbE/QUQnWO5reE1B4JXGTl186vos9f H9eA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=1kt8Pfq43g42ZTuGel3KWUrOcZMTLFPWxdZ8oxo4qCo=; b=a/2OoHJrPBFGtDneJOcIg7OAcxAtKwjpRnLZuoaV0ZAihhCFHDtV1MrQf3+o0Iu9xY fUuMRngx1//R75zbdJ/oEOI+qzdCjBA9kaN8sVb64mpOlLVqi9jNwwmlIOYCIIdG5whc jaH84CBzfxXZEjVLRwx2eKl0yplI9rSoGeuSe3xs4cGB6HqgDGVTaRGQOvVZm0MqduHT D49N3y2dOm6GPCOATInkQAXkke1I4pI67DDMz5+xc38uL6OEuTpHs8P98aexYITx2vdI /LfltlE4Nq2EghzTxZRLa9hSTfaXZie86GJrO3WptyoAOq/Ahn5VhnhoBWU8dGi6AfvE qx5w== X-Gm-Message-State: APjAAAWikBTND1ya2rHExI1kO4hsTx70isS5UjZ6V7c+GTKjD3YrwZbF orIfyIl0i/ByLNr38Fof1Z8+y4w9 X-Google-Smtp-Source: APXvYqzYfG+JKg2xuVbDM8OMxU8T7UcEeqrcbyMbkNKvMQc0nZqYr3tGLtKpju6t0Sdg8a3vEQlNkA== X-Received: by 2002:a05:600c:2904:: with SMTP id i4mr13221721wmd.113.1572750815493; Sat, 02 Nov 2019 20:13:35 -0700 (PDT) Received: from fainelli-desktop.igp.broadcom.net ([192.19.223.252]) by smtp.gmail.com with ESMTPSA id w10sm532649wmd.26.2019.11.02.20.13.33 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 02 Nov 2019 20:13:34 -0700 (PDT) From: Florian Fainelli To: netdev@vger.kernel.org Cc: rmk+kernel@armlinux.org.uk, hkallweit1@gmail.com, Florian Fainelli , Andrew Lunn , Vivien Didelot , "David S. Miller" , linux-kernel@vger.kernel.org (open list) Subject: [PATCH net-next] net: dsa: Fix use after free in dsa_switch_remove() Date: Sat, 2 Nov 2019 20:13:26 -0700 Message-Id: <20191103031326.26873-1-f.fainelli@gmail.com> X-Mailer: git-send-email 2.17.1 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org The order in which the ports are deleted from the list and freed and the call to dsa_tree_remove_switch() is done is reversed, which leads to an use after free condition. Reverse the two: first tear down the ports and switch from the fabric, then free the ports associated with that switch fabric. Fixes: 05f294a85235 ("net: dsa: allocate ports on touch") Signed-off-by: Florian Fainelli --- net/dsa/dsa2.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/dsa/dsa2.c b/net/dsa/dsa2.c index ff2fa3950c62..9ef2caa13f27 100644 --- a/net/dsa/dsa2.c +++ b/net/dsa/dsa2.c @@ -874,12 +874,13 @@ static void dsa_switch_remove(struct dsa_switch *ds) struct dsa_switch_tree *dst = ds->dst; struct dsa_port *dp, *next; + dsa_tree_teardown(dst); + list_for_each_entry_safe(dp, next, &dst->ports, list) { list_del(&dp->list); kfree(dp); } - dsa_tree_teardown(dst); dsa_tree_put(dst); } -- 2.17.1