From patchwork Thu Feb 21 05:49:38 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joel Fernandes X-Patchwork-Id: 1045763 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=joelfernandes.org Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=joelfernandes.org header.i=@joelfernandes.org header.b="qShTQcTd"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 444k8B37cKz9sBF for ; Thu, 21 Feb 2019 16:50:02 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726729AbfBUFuB (ORCPT ); Thu, 21 Feb 2019 00:50:01 -0500 Received: from mail-qt1-f196.google.com ([209.85.160.196]:38079 "EHLO mail-qt1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726559AbfBUFt7 (ORCPT ); Thu, 21 Feb 2019 00:49:59 -0500 Received: by mail-qt1-f196.google.com with SMTP id s1so4080958qte.5 for ; Wed, 20 Feb 2019 21:49:58 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=joelfernandes.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=Zc6wY8rNCewGZVDgSPtq8BlfOuPURI6nN/IPxD75L4o=; b=qShTQcTd754XHzpJwI56vyDHKKusPA4VcL8Y+AAFePWXkeiXxU3ZDqJWhjH7k4OOyI TXzMqcdej7TKfKh4dmxMtAfmzK8tYkqqPaq7S6GQZmzMsCVbt1M+LHHodwNxQfjthC6c HlkgBykGg3dfgV7xxcqaGoC/3UD8IgTj43wn4= 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:in-reply-to :references:mime-version:content-transfer-encoding; bh=Zc6wY8rNCewGZVDgSPtq8BlfOuPURI6nN/IPxD75L4o=; b=BwVCaLxvVXhBoLocEx6c90qqV7C+dL1/1TCgK+V3VCqMblvoAHjZ9BXVdMriw/WRUB GKL1ofSJmOnw4qiYTDoldaQXPZgWGDp+t1m6HSWqj5XAOYmx6NSzpx2BcXf5Y4Si3yrn Wa43KTooOlGudbnVT9hDaIERmUoilhRrz4FSoSIBDJT8MX2ouKslNprGBihCQmx5GZCw 6dE4U2j1kZzuxnoHJ4QvryK1FmGy5hoeRFPd4X6uBnSijF5zQJFwvHEiEYo6rlHJpq1R /l5370T+vsCOIxFtIzAILL/mYOR+JS7eUCUfvRnPPfk4SIgy5Pba81uC0PjWFTEIDsdt uGPA== X-Gm-Message-State: AHQUAua4bJjxihyNy2WaUUbJQkX/HV2W64f0UhDLdtSqx9rFIOrAH3Zr V6mjAcv3iXzwoNLAO21ZA/HS3Q== X-Google-Smtp-Source: AHgI3IZDtKyppM3lu4JTN4viMA53x3Iwpt/uImBH+1nEX2ySNpJsklPizojrXDvzLS5DPjNzUrdbrg== X-Received: by 2002:ac8:35ad:: with SMTP id k42mr5322820qtb.4.1550728198163; Wed, 20 Feb 2019 21:49:58 -0800 (PST) Received: from joelaf.cam.corp.google.com ([2620:0:1004:1100:cca9:fccc:8667:9bdc]) by smtp.gmail.com with ESMTPSA id k185sm11561219qkd.62.2019.02.20.21.49.56 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 20 Feb 2019 21:49:57 -0800 (PST) From: "Joel Fernandes (Google)" To: linux-kernel@vger.kernel.org Cc: "Joel Fernandes (Google)" , Alexei Starovoitov , Christian Brauner , Daniel Borkmann , David Ahern , "David S. Miller" , Ido Schimmel , Ingo Molnar , intel-wired-lan@lists.osuosl.org (moderated list:INTEL ETHERNET DRIVERS), Jakub Kicinski , Jeff Kirsher , Jesper Dangaard Brouer , John Fastabend , Josh Triplett , keescook@chromium.org, Lai Jiangshan , Martin KaFai Lau , Mathieu Desnoyers , netdev@vger.kernel.org, "Paul E. McKenney" , Peter Zijlstra , rcu@vger.kernel.org, Song Liu , Steven Rostedt , xdp-newbies@vger.kernel.org, Yonghong Song Subject: [PATCH RFC 1/5] net: rtnetlink: Fix incorrect RCU API usage Date: Thu, 21 Feb 2019 00:49:38 -0500 Message-Id: <20190221054942.132388-2-joel@joelfernandes.org> X-Mailer: git-send-email 2.21.0.rc0.258.g878e2cd30e-goog In-Reply-To: <20190221054942.132388-1-joel@joelfernandes.org> References: <20190221054942.132388-1-joel@joelfernandes.org> MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org rtnl_register_internal() and rtnl_unregister_all tries to directly dereference an RCU protected pointed outside RCU read side section. While this is Ok to do since a lock is held, let us use the correct API to avoid programmer bugs in the future. This also fixes sparse warnings arising from not using RCU API. net/core/rtnetlink.c:332:13: warning: incorrect type in assignment (different address spaces) net/core/rtnetlink.c:332:13: expected struct rtnl_link **tab net/core/rtnetlink.c:332:13: got struct rtnl_link *[noderef] * Signed-off-by: Joel Fernandes (Google) --- net/core/rtnetlink.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 5ea1bed08ede..98be4b4818a9 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -188,7 +188,7 @@ static int rtnl_register_internal(struct module *owner, msgindex = rtm_msgindex(msgtype); rtnl_lock(); - tab = rtnl_msg_handlers[protocol]; + tab = rtnl_dereference(rtnl_msg_handlers[protocol]); if (tab == NULL) { tab = kcalloc(RTM_NR_MSGTYPES, sizeof(void *), GFP_KERNEL); if (!tab) @@ -329,7 +329,7 @@ void rtnl_unregister_all(int protocol) BUG_ON(protocol < 0 || protocol > RTNL_FAMILY_MAX); rtnl_lock(); - tab = rtnl_msg_handlers[protocol]; + tab = rtnl_dereference(rtnl_msg_handlers[protocol]); if (!tab) { rtnl_unlock(); return;