From patchwork Thu May 20 09:24:12 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: 445242 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=-18.8 required=3.0 tests=BAYES_00,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 D3DBBC43461 for ; Thu, 20 May 2021 11:25:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BC260613AD for ; Thu, 20 May 2021 11:25:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240171AbhETL0W (ORCPT ); Thu, 20 May 2021 07:26:22 -0400 Received: from mail.kernel.org ([198.145.29.99]:44180 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241563AbhETLYu (ORCPT ); Thu, 20 May 2021 07:24:50 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 6681D61971; Thu, 20 May 2021 10:12:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1621505570; bh=IqVgUf0A9O2k0LqHz61gCW9Mhs8q3/BFxzLuq65IT64=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=f6IpXtGGEOqcT2p6U8lgM1cACT5CoRO2jQA2szmqfsWsWQaGh5q7aCpUumr15bTBz eRFZKerq4l8rNlJ9P9tHho9YuQvaqP/iWfFMv/zBeoZpDvBscJS4ToI4wMeLW7sqnh gVqs7vrCMuRl3BJ61+0vWS6TJ7LdWXvv+LmRmfcU= 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 4.4 188/190] ipv6: remove extra dev_hold() for fallback tunnels Date: Thu, 20 May 2021 11:24:12 +0200 Message-Id: <20210520092108.384557826@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210520092102.149300807@linuxfoundation.org> References: <20210520092102.149300807@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 @@ -350,7 +350,6 @@ static struct ip6_tnl *ip6gre_tunnel_loc if (!(nt->parms.o_flags & GRE_SEQ)) dev->features |= NETIF_F_LLTX; - dev_hold(dev); ip6gre_tunnel_link(ign, nt); return nt; @@ -1310,8 +1309,6 @@ static void ip6gre_fb_tunnel_init(struct strcpy(tunnel->parms.name, dev->name); tunnel->hlen = sizeof(struct ipv6hdr) + 4; - - dev_hold(dev); } --- a/net/ipv6/ip6_tunnel.c +++ b/net/ipv6/ip6_tunnel.c @@ -1614,7 +1614,6 @@ 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 @@ -931,7 +931,6 @@ 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 @@ -1413,7 +1413,6 @@ 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); }