From patchwork Wed Mar 31 21:38:11 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Dumazet X-Patchwork-Id: 12176499 X-Patchwork-Delegate: kuba@kernel.org 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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, 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 B4782C433ED for ; Wed, 31 Mar 2021 21:38:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8075061075 for ; Wed, 31 Mar 2021 21:38:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232644AbhCaViU (ORCPT ); Wed, 31 Mar 2021 17:38:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54226 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231210AbhCaViR (ORCPT ); Wed, 31 Mar 2021 17:38:17 -0400 Received: from mail-pj1-x1033.google.com (mail-pj1-x1033.google.com [IPv6:2607:f8b0:4864:20::1033]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9D846C061574 for ; Wed, 31 Mar 2021 14:38:17 -0700 (PDT) Received: by mail-pj1-x1033.google.com with SMTP id bt4so10200900pjb.5 for ; Wed, 31 Mar 2021 14:38:17 -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:mime-version :content-transfer-encoding; bh=NZm7RaKIS+bgLQU/KWuJ5y+M6y9GHWGtZvpwkfMJY4Q=; b=TR3gNRLrDW37AsRibJTCn1Zj99VvKyUhbbuxSy/Si9bi/rcbYAtPgDpZxJCk/D7Q59 GfRbMYx74At2DzqHR5y3G9n+6YizVQMjnupXuE9sLsV9XlGEwnxCeEyz1305prXYCLOs 9a9hYFRdPI+XKR4zOZDn7iXjL1/cBiWdM9OExOlXKSNkoGy+hTv0jWiKItlZcmeOoVfH BobugeQlZznXxQqY/pqI3mYbcLpKByKh37OzY5D/4RdaBmsTplqTCLOkdMFv5f8zzveN GVtqNutEleDmYvEQzez0E0xpjjSi/dqtE0gpmHfWja0Qq19ED24y+pNCbxm9EdDzlD2T 34KQ== 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:mime-version :content-transfer-encoding; bh=NZm7RaKIS+bgLQU/KWuJ5y+M6y9GHWGtZvpwkfMJY4Q=; b=VF4oUl5uuaj29+Thd9KKv5c1py6YWAyV5Ce7iHYdF5AZkudGaMHzxrKurXy9aYaT/t IX7NWdRL8bUzZSxOfkZyGJH9RQvmGz5ewgsk6fksGFjXdSgGDqY4x471OPSulwlmujXr Ck+a1qPNtdjNAu64DqY4f/MWDQyX2Aeoo+OHH8AfO3ZMvaa3/obYIjYUNYsnLCZfej0c RZWyitn9qduxDsMNMenCEm7okJc6FuShpjn/06A8+KsPiW3Wb7+4Y/VwzBLNKTZbdOfF Fp3wwHfra9DBhzMKo4qd4Jm1a4Lb3qZaNUZ8eo0wEKf9Z6WwsjAmhQDQsjXefnXGZS/N xvgQ== X-Gm-Message-State: AOAM530x0kU6kBGfWwwPHdqiCd2mU3CVWbtN5RidpPCwdF4xd8HTwaXq IEA8w/+cmOGRDfRaX9uzn2A= X-Google-Smtp-Source: ABdhPJwvyEj3+VEzAI0oUjM8eefWBF20GcPknci9niqcJP6tVJNWVUaDuIwiD5j3OyWhRq0BXKwv2g== X-Received: by 2002:a17:90a:64c7:: with SMTP id i7mr5324860pjm.95.1617226697273; Wed, 31 Mar 2021 14:38:17 -0700 (PDT) Received: from edumazet1.svl.corp.google.com ([2620:15c:2c4:201:9107:b184:4a71:45d0]) by smtp.gmail.com with ESMTPSA id fh19sm3171017pjb.33.2021.03.31.14.38.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 31 Mar 2021 14:38:16 -0700 (PDT) From: Eric Dumazet To: "David S . Miller" , Jakub Kicinski Cc: netdev , Eric Dumazet , Eric Dumazet , syzbot Subject: [PATCH net-next] ipv6: remove extra dev_hold() for fallback tunnels Date: Wed, 31 Mar 2021 14:38:11 -0700 Message-Id: <20210331213811.847054-1-eric.dumazet@gmail.com> X-Mailer: git-send-email 2.31.0.291.g576ba9dcdaf-goog MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org From: Eric Dumazet 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 --- 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(-) diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c index 9689bf9f46f347562330a4d8630c0b0b13a411fc..bc224f917bbd53beb9b8af5bdef3fb9794b8ee44 100644 --- a/net/ipv6/ip6_gre.c +++ b/net/ipv6/ip6_gre.c @@ -387,7 +387,6 @@ static struct ip6_tnl *ip6gre_tunnel_locate(struct net *net, if (!(nt->parms.o_flags & TUNNEL_SEQ)) dev->features |= NETIF_F_LLTX; - dev_hold(dev); ip6gre_tunnel_link(ign, nt); return nt; @@ -1539,8 +1538,6 @@ static void ip6gre_fb_tunnel_init(struct net_device *dev) strcpy(tunnel->parms.name, dev->name); tunnel->hlen = sizeof(struct ipv6hdr) + 4; - - dev_hold(dev); } static struct inet6_protocol ip6gre_protocol __read_mostly = { diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c index 67ee9d58ec5efcc81e8b27406bd4f57a0caea70b..07a0a06a9b52bc9974e2f36b1477c341c952f94a 100644 --- a/net/ipv6/ip6_tunnel.c +++ b/net/ipv6/ip6_tunnel.c @@ -1925,7 +1925,6 @@ static int __net_init ip6_fb_tnl_dev_init(struct net_device *dev) 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; diff --git a/net/ipv6/ip6_vti.c b/net/ipv6/ip6_vti.c index a018afdb3e062c9e664d4ca424176a859f0a332c..856e46ad0895b47b58896852afee3d4a398b139e 100644 --- a/net/ipv6/ip6_vti.c +++ b/net/ipv6/ip6_vti.c @@ -963,7 +963,6 @@ static int __net_init vti6_fb_tnl_dev_init(struct net_device *dev) 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; diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c index 488d3181aec3a5558dbefb6145400627535df761..ff2ca2e7c7f5045663069ea572560d58abee2970 100644 --- a/net/ipv6/sit.c +++ b/net/ipv6/sit.c @@ -1470,7 +1470,6 @@ static void __net_init ipip6_fb_tunnel_init(struct net_device *dev) iph->ihl = 5; iph->ttl = 64; - dev_hold(dev); rcu_assign_pointer(sitn->tunnels_wc[0], tunnel); }