From patchwork Thu Jun 10 10:45:37 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nikolay Aleksandrov X-Patchwork-Id: 458348 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=-16.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, 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 E8EB1C47094 for ; Thu, 10 Jun 2021 10:46:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BD0D6613D0 for ; Thu, 10 Jun 2021 10:46:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230190AbhFJKr5 (ORCPT ); Thu, 10 Jun 2021 06:47:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52452 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229778AbhFJKrz (ORCPT ); Thu, 10 Jun 2021 06:47:55 -0400 Received: from mail-ej1-x62f.google.com (mail-ej1-x62f.google.com [IPv6:2a00:1450:4864:20::62f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 306D6C061574 for ; Thu, 10 Jun 2021 03:45:49 -0700 (PDT) Received: by mail-ej1-x62f.google.com with SMTP id a11so42700551ejf.3 for ; Thu, 10 Jun 2021 03:45:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=blackwall-org.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=hD8fPsRet4ILI2ZqLWaNZjnbEkYaKbtss9dKK+ZgOyw=; b=BaLArFcF4khkys2mXt7mJw8mXxlXO+j6UB9ENdQ0lvXBtBH84PsRaXiwWEDRHCbkwF 1HGnFogLXJVOTieIqs7UAHkAXpsMiCgSGQQ+SZtDf5bbJs1Hez2mUBx71Bymq7hNJM7B dJaxXn2RR3QEIOzsVxjWyYyn5ZIYAc1nSBzvaCtsGtTV69KL4yv7LA2aaxIe1TVe9nxF Qp0HvM57VaUnvwQSd0H4/SAasWejC6G58+HYxpEmh3U8aTArYLfe9HafhUmFZ/PkWuu2 h+xGi56fqX/RZug+X8sBcQJMAQtsdmOpLpQPsLBYAwe6kgo7AwUy+bVdTLwyXCCy7Flx 5z6g== 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=hD8fPsRet4ILI2ZqLWaNZjnbEkYaKbtss9dKK+ZgOyw=; b=kqeHMKD79SsFsPLYL7vf+PXq5+8lDSHEVvIrMlyRaLP/g2dHaP82PiYHOYdWe8USB9 O9z3TP9CDixx5GEMDCd8/xO0wH8IT5Gf30PVbnIiQDyET3TY+dlaMFFo5oCGhRyol3Ld oZoKv1cfM1mjSfAIRyzbG3ySuiB0mSs/vGg0KDnmumdyzEHqXpDtD0mJQGBez+0M+dod wbzzGN3HB45Yr3zif5MiphXJM4MvCyRp9lxGtgltjZV+nGYzATwG83qjQN5YRJhbmozz Ty/jOTncZbdrpX+SYNamwE++hWWrKe4CNI5G9eCSehORcxwL8i89P26Ta836J9cvyPAj YVng== X-Gm-Message-State: AOAM533pxQfCzyG28EU38q2vP+ys+1lf3N2Hc6PYgG27iGwLHPJ/O5FE imF3P0wmY3OOmpDehLLah0OAljztUx7U8p67Hsw= X-Google-Smtp-Source: ABdhPJy0Ntl5eLRAzxpza4PaVoYcOab3BALHOh6a//cqI41PcQWWbcNGblDv/YLXq65AE5MzPpaaxw== X-Received: by 2002:a17:906:9888:: with SMTP id zc8mr3759147ejb.26.1623321947473; Thu, 10 Jun 2021 03:45:47 -0700 (PDT) Received: from debil.vdiclient.nvidia.com (84-238-136-197.ip.btc-net.bg. [84.238.136.197]) by smtp.gmail.com with ESMTPSA id y1sm866526ejl.7.2021.06.10.03.45.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 10 Jun 2021 03:45:47 -0700 (PDT) From: Nikolay Aleksandrov To: netdev@vger.kernel.org Cc: roopa@nvidia.com, davem@davemloft.net, bridge@lists.linux-foundation.org, Nikolay Aleksandrov Subject: [PATCH net 2/2] net: bridge: fix vlan tunnel dst refcnt when egressing Date: Thu, 10 Jun 2021 13:45:37 +0300 Message-Id: <20210610104537.119538-3-razor@blackwall.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210610104537.119538-1-razor@blackwall.org> References: <20210610104537.119538-1-razor@blackwall.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Nikolay Aleksandrov The egress tunnel code uses dst_clone() and directly sets the result which is wrong because the entry might have 0 refcnt or be already deleted, causing number of problems. It also triggers the WARN_ON() in dst_hold()[1] when a refcnt couldn't be taken. Fix it by using dst_hold_safe() and checking if a reference was actually taken before setting the dst. [1] dmesg WARN_ON log and following refcnt errors WARNING: CPU: 5 PID: 38 at include/net/dst.h:230 br_handle_egress_vlan_tunnel+0x10b/0x134 [bridge] Modules linked in: 8021q garp mrp bridge stp llc bonding ipv6 virtio_net CPU: 5 PID: 38 Comm: ksoftirqd/5 Kdump: loaded Tainted: G W 5.13.0-rc3+ #360 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-1.fc33 04/01/2014 RIP: 0010:br_handle_egress_vlan_tunnel+0x10b/0x134 [bridge] Code: e8 85 bc 01 e1 45 84 f6 74 90 45 31 f6 85 db 48 c7 c7 a0 02 19 a0 41 0f 94 c6 31 c9 31 d2 44 89 f6 e8 64 bc 01 e1 85 db 75 02 <0f> 0b 31 c9 31 d2 44 89 f6 48 c7 c7 70 02 19 a0 e8 4b bc 01 e1 49 RSP: 0018:ffff8881003d39e8 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffffa01902a0 RBP: ffff8881040c6700 R08: 0000000000000000 R09: 0000000000000001 R10: 2ce93d0054fe0d00 R11: 54fe0d00000e0000 R12: ffff888109515000 R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000401 FS: 0000000000000000(0000) GS:ffff88822bf40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f42ba70f030 CR3: 0000000109926000 CR4: 00000000000006e0 Call Trace: br_handle_vlan+0xbc/0xca [bridge] __br_forward+0x23/0x164 [bridge] deliver_clone+0x41/0x48 [bridge] br_handle_frame_finish+0x36f/0x3aa [bridge] ? skb_dst+0x2e/0x38 [bridge] ? br_handle_ingress_vlan_tunnel+0x3e/0x1c8 [bridge] ? br_handle_frame_finish+0x3aa/0x3aa [bridge] br_handle_frame+0x2c3/0x377 [bridge] ? __skb_pull+0x33/0x51 ? vlan_do_receive+0x4f/0x36a ? br_handle_frame_finish+0x3aa/0x3aa [bridge] __netif_receive_skb_core+0x539/0x7c6 ? __list_del_entry_valid+0x16e/0x1c2 __netif_receive_skb_list_core+0x6d/0xd6 netif_receive_skb_list_internal+0x1d9/0x1fa gro_normal_list+0x22/0x3e dev_gro_receive+0x55b/0x600 ? detach_buf_split+0x58/0x140 napi_gro_receive+0x94/0x12e virtnet_poll+0x15d/0x315 [virtio_net] __napi_poll+0x2c/0x1c9 net_rx_action+0xe6/0x1fb __do_softirq+0x115/0x2d8 run_ksoftirqd+0x18/0x20 smpboot_thread_fn+0x183/0x19c ? smpboot_unregister_percpu_thread+0x66/0x66 kthread+0x10a/0x10f ? kthread_mod_delayed_work+0xb6/0xb6 ret_from_fork+0x22/0x30 ---[ end trace 49f61b07f775fd2b ]--- dst_release: dst:00000000c02d677a refcnt:-1 dst_release underflow Fixes: 11538d039ac6 ("bridge: vlan dst_metadata hooks in ingress and egress paths") Signed-off-by: Nikolay Aleksandrov --- net/bridge/br_vlan_tunnel.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/bridge/br_vlan_tunnel.c b/net/bridge/br_vlan_tunnel.c index 03de461a0d44..01017448ebde 100644 --- a/net/bridge/br_vlan_tunnel.c +++ b/net/bridge/br_vlan_tunnel.c @@ -204,8 +204,8 @@ int br_handle_egress_vlan_tunnel(struct sk_buff *skb, return err; tunnel_dst = rcu_dereference(vlan->tinfo.tunnel_dst); - if (tunnel_dst) - skb_dst_set(skb, dst_clone(&tunnel_dst->dst)); + if (tunnel_dst && dst_hold_safe(&tunnel_dst->dst)) + skb_dst_set(skb, &tunnel_dst->dst); return 0; }