From patchwork Thu May 20 09:23:10 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 444359 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=-19.1 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=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 08AF0C433ED for ; Thu, 20 May 2021 10:14:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E40F6613F1 for ; Thu, 20 May 2021 10:14:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235541AbhETKQM (ORCPT ); Thu, 20 May 2021 06:16:12 -0400 Received: from mail.kernel.org ([198.145.29.99]:47660 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236161AbhETKO3 (ORCPT ); Thu, 20 May 2021 06:14:29 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 48F8F61972; Thu, 20 May 2021 09:44:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1621503880; bh=31IfYWV6K9GziwTk3t6vQNdd60MuemF/RY8rzmXM+p0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=xe2Z/eEbhsbCKatIgJjq4MqFe4ICT3B9G9FBXFScsHOGOv0c0YeM7BFQxsx6tDOfj LlRFvVxjxe5LLPFO4aKZPUWAxhnwL+2Xzl6XADNFzMjR1zWyvrHlTGG6t94motg5s8 WAYGZd/LPGheJtprzGtIgn3IWlYDdBicb43DGiM4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Dumazet , syzbot , "David S. Miller" Subject: [PATCH 4.19 421/425] ipv6: remove extra dev_hold() for fallback tunnels Date: Thu, 20 May 2021 11:23:10 +0200 Message-Id: <20210520092145.235912258@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210520092131.308959589@linuxfoundation.org> References: <20210520092131.308959589@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Eric Dumazet commit 0d7a7b2014b1a499a0fe24c9f3063d7856b5aaaf upstream. My previous commits added a dev_hold() in tunnels ndo_init(), but forgot to remove it from special functions setting up fallback tunnels. Fallback tunnels do call their respective ndo_init() This leads to various reports like : unregister_netdevice: waiting for ip6gre0 to become free. Usage count = 2 Fixes: 48bb5697269a ("ip6_tunnel: sit: proper dev_{hold|put} in ndo_[un]init methods") Fixes: 6289a98f0817 ("sit: proper dev_{hold|put} in ndo_[un]init methods") Fixes: 40cb881b5aaa ("ip6_vti: proper dev_{hold|put} in ndo_[un]init methods") Fixes: 7f700334be9a ("ip6_gre: proper dev_{hold|put} in ndo_[un]init methods") Signed-off-by: Eric Dumazet Reported-by: syzbot Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv6/ip6_gre.c | 3 --- net/ipv6/ip6_tunnel.c | 1 - net/ipv6/ip6_vti.c | 1 - net/ipv6/sit.c | 1 - 4 files changed, 6 deletions(-) --- a/net/ipv6/ip6_gre.c +++ b/net/ipv6/ip6_gre.c @@ -392,7 +392,6 @@ static struct ip6_tnl *ip6gre_tunnel_loc if (!(nt->parms.o_flags & TUNNEL_SEQ)) dev->features |= NETIF_F_LLTX; - dev_hold(dev); ip6gre_tunnel_link(ign, nt); return nt; @@ -1546,8 +1545,6 @@ static void ip6gre_fb_tunnel_init(struct strcpy(tunnel->parms.name, dev->name); tunnel->hlen = sizeof(struct ipv6hdr) + 4; - - dev_hold(dev); } static struct inet6_protocol ip6gre_protocol __read_mostly = { --- a/net/ipv6/ip6_tunnel.c +++ b/net/ipv6/ip6_tunnel.c @@ -1909,7 +1909,6 @@ static int __net_init ip6_fb_tnl_dev_ini struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); t->parms.proto = IPPROTO_IPV6; - dev_hold(dev); rcu_assign_pointer(ip6n->tnls_wc[0], t); return 0; --- a/net/ipv6/ip6_vti.c +++ b/net/ipv6/ip6_vti.c @@ -956,7 +956,6 @@ static int __net_init vti6_fb_tnl_dev_in struct vti6_net *ip6n = net_generic(net, vti6_net_id); t->parms.proto = IPPROTO_IPV6; - dev_hold(dev); rcu_assign_pointer(ip6n->tnls_wc[0], t); return 0; --- a/net/ipv6/sit.c +++ b/net/ipv6/sit.c @@ -1421,7 +1421,6 @@ static void __net_init ipip6_fb_tunnel_i iph->ihl = 5; iph->ttl = 64; - dev_hold(dev); rcu_assign_pointer(sitn->tunnels_wc[0], tunnel); }