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=-20.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,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 BF750C07E95 for ; Mon, 19 Jul 2021 15:02:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9FF386124C for ; Mon, 19 Jul 2021 15:02:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242542AbhGSOWE (ORCPT ); Mon, 19 Jul 2021 10:22:04 -0400 Received: from mail.kernel.org ([198.145.29.99]:55504 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242600AbhGSOUF (ORCPT ); Mon, 19 Jul 2021 10:20:05 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 3EF7561263; Mon, 19 Jul 2021 15:00:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1626706844; bh=Avt3c1kTwwQobc01mLPNGoA7Y6A7NkOUJIcZUU2Fwu4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=G7rDWCULwk3ix7nfO3zkzw1iEiehCepwKgg5VLE9Jbtmn/6x1T9vXfKmkxwajCP+M paTL0cCIQ8/eYuIt1S2Ww1DA3O2M8yMxkBAFXkmtIPAKdAE/9aN0Qk+ao704DAYFES SKEBp5dhnsQDXy+2DUFpx0SgCM+xJomoPHqhXvu8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Oliver Hartkopp , Marc Kleine-Budde Subject: [PATCH 4.4 124/188] can: gw: synchronize rcu operations before removing gw job entry Date: Mon, 19 Jul 2021 16:51:48 +0200 Message-Id: <20210719144940.542402820@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210719144913.076563739@linuxfoundation.org> References: <20210719144913.076563739@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Oliver Hartkopp commit fb8696ab14adadb2e3f6c17c18ed26b3ecd96691 upstream. can_can_gw_rcv() is called under RCU protection, so after calling can_rx_unregister(), we have to call synchronize_rcu in order to wait for any RCU read-side critical sections to finish before removing the kmem_cache entry with the referenced gw job entry. Link: https://lore.kernel.org/r/20210618173645.2238-1-socketcan@hartkopp.net Fixes: c1aabdf379bc ("can-gw: add netlink based CAN routing") Cc: linux-stable Signed-off-by: Oliver Hartkopp Signed-off-by: Marc Kleine-Budde Signed-off-by: Greg Kroah-Hartman --- net/can/gw.c | 3 +++ 1 file changed, 3 insertions(+) --- a/net/can/gw.c +++ b/net/can/gw.c @@ -497,6 +497,7 @@ static int cgw_notifier(struct notifier_ if (gwj->src.dev == dev || gwj->dst.dev == dev) { hlist_del(&gwj->list); cgw_unregister_filter(gwj); + synchronize_rcu(); kmem_cache_free(cgw_cache, gwj); } } @@ -941,6 +942,7 @@ static void cgw_remove_all_jobs(void) hlist_for_each_entry_safe(gwj, nx, &cgw_list, list) { hlist_del(&gwj->list); cgw_unregister_filter(gwj); + synchronize_rcu(); kmem_cache_free(cgw_cache, gwj); } } @@ -1008,6 +1010,7 @@ static int cgw_remove_job(struct sk_buff hlist_del(&gwj->list); cgw_unregister_filter(gwj); + synchronize_rcu(); kmem_cache_free(cgw_cache, gwj); err = 0; break;