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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2FAAEC433F5 for ; Tue, 17 May 2022 08:23:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236827AbiEQIXm (ORCPT ); Tue, 17 May 2022 04:23:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44928 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234309AbiEQIXk (ORCPT ); Tue, 17 May 2022 04:23:40 -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 83FFF31533 for ; Tue, 17 May 2022 01:23:38 -0700 (PDT) Received: by mail-pj1-x1033.google.com with SMTP id gg20so6668113pjb.1 for ; Tue, 17 May 2022 01:23:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=5K4eCNob39YXKtKuikmIRaukZjZAKrammohCk/UyOMs=; b=S4OMOfNspNL7OLIpBifgmG4wUohTQ2ghuip5H55CwDnmnulf2Y1FwGHMyfNZYv1Gdp oqXvuThcZ+aJ4q1Szu1tGv5yrExGOeh12GqErc7h1U0bmfGqxoH7MHowvubh1ozVh4Ef X4EP/Svya/yO94lVyk73sW9rBv+wB0tJVL365HidEEy8NIKTQbbdgpqB+QQOMjQTof4K 6iZFbTfdF7tF8l0JKTIeo/xLI7C1ashQQxGBNG5IH2WPBgPDM5CW06+7RNv/MvpgNYRd FGAiPo7JlIHZ2dYyZTE0Sti6ejn/g7f12TRzZJ7Jzaq47wIwqKrUB44HyUbECRRdOzcd O+Eg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=5K4eCNob39YXKtKuikmIRaukZjZAKrammohCk/UyOMs=; b=iEJCoqE4uo4v65vnXcAesnwDpi52Y27s/n1oab0thnAAIH4t57rXP2gYdXoF/RsIsP vRyGqa4BDcsvPHJpwRwSvLzTN2aZV9z8GhHOHF8xdGeNdwZDckG4Njc6BDeOfvvzMoj2 5T3R0eKnCYeaymDq9Gg2dp7oLQScbBAjnMmi86P566w1mJnzvyIT6HjRDRJkD7SOEcVA xMbtYQT1VfuUHcZrkaUrXfOoodkettr70Zl7tVCwyMuWrgtDRZAiBvEfeuXn37hd6Rr5 26pbTkLujsc4JT49ue2YQ8wfngwkh21LUCt/m5jQlZkxbaNK0GtbE7b7dRtIhoUpWnxx 6SpQ== X-Gm-Message-State: AOAM530XI/ulIzdoWjKykXLkeIX8CWLEsnygfd1CtkM+URL05tYnBhkF SGJHWnJdKgGFVqA9DIWp/7P9+SFEWwO3Yg== X-Google-Smtp-Source: ABdhPJz6QNFVa0ufrLV9YDKmWBr09Ofx4ri8zoYbErORVd6JaPnBKlpZtwaKcCCTezKSqlFbSSJ86g== X-Received: by 2002:a17:90b:1e09:b0:1dc:6d9a:4f57 with SMTP id pg9-20020a17090b1e0900b001dc6d9a4f57mr34553474pjb.17.1652775817652; Tue, 17 May 2022 01:23:37 -0700 (PDT) Received: from Laptop-X1.redhat.com ([209.132.188.80]) by smtp.gmail.com with ESMTPSA id w18-20020a62c712000000b0050dc7628166sm8263027pfg.64.2022.05.17.01.23.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 17 May 2022 01:23:37 -0700 (PDT) From: Hangbin Liu To: netdev@vger.kernel.org Cc: Jay Vosburgh , Veaceslav Falico , Andy Gospodarek , "David S . Miller" , Jakub Kicinski , David Ahern , Jonathan Toppins , Eric Dumazet , Paolo Abeni , Hangbin Liu , syzbot+92beb3d46aab498710fa@syzkaller.appspotmail.com, Vladimir Oltean Subject: [PATCHv2 net] bonding: fix missed rcu protection Date: Tue, 17 May 2022 16:23:12 +0800 Message-Id: <20220517082312.805824-1-liuhangbin@gmail.com> X-Mailer: git-send-email 2.35.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org When removing the rcu_read_lock in bond_ethtool_get_ts_info() as discussed [1], I didn't notice it could be called via setsockopt, which doesn't hold rcu lock, as syzbot pointed: Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 bond_option_active_slave_get_rcu include/net/bonding.h:353 [inline] bond_ethtool_get_ts_info+0x32c/0x3a0 drivers/net/bonding/bond_main.c:5595 __ethtool_get_ts_info+0x173/0x240 net/ethtool/common.c:554 ethtool_get_phc_vclocks+0x99/0x110 net/ethtool/common.c:568 sock_timestamping_bind_phc net/core/sock.c:869 [inline] sock_set_timestamping+0x3a3/0x7e0 net/core/sock.c:916 sock_setsockopt+0x543/0x2ec0 net/core/sock.c:1221 __sys_setsockopt+0x55e/0x6a0 net/socket.c:2223 __do_sys_setsockopt net/socket.c:2238 [inline] __se_sys_setsockopt net/socket.c:2235 [inline] __x64_sys_setsockopt+0xba/0x150 net/socket.c:2235 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f8902c8eb39 Fix it by adding rcu_read_lock and take a ref on the real_dev. [1] https://lore.kernel.org/netdev/27565.1642742439@famine/ Reported-by: syzbot+92beb3d46aab498710fa@syzkaller.appspotmail.com Fixes: aa6034678e87 ("bonding: use rcu_dereference_rtnl when get bonding active slave") Suggested-by: Vladimir Oltean Suggested-by: Jakub Kicinski Signed-off-by: Hangbin Liu --- v2: add ref on the real_dev as Jakub and Paolo suggested. --- drivers/net/bonding/bond_main.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index 38e152548126..fcaa5ccea7af 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -5591,24 +5591,35 @@ static int bond_ethtool_get_ts_info(struct net_device *bond_dev, const struct ethtool_ops *ops; struct net_device *real_dev; struct phy_device *phydev; + int ret = 0; + rcu_read_lock(); real_dev = bond_option_active_slave_get_rcu(bond); if (real_dev) { + dev_hold(real_dev); + rcu_read_unlock(); ops = real_dev->ethtool_ops; phydev = real_dev->phydev; if (phy_has_tsinfo(phydev)) { - return phy_ts_info(phydev, info); + ret = phy_ts_info(phydev, info); + goto out; } else if (ops->get_ts_info) { - return ops->get_ts_info(real_dev, info); + ret = ops->get_ts_info(real_dev, info); + goto out; } + } else { + rcu_read_unlock(); } info->so_timestamping = SOF_TIMESTAMPING_RX_SOFTWARE | SOF_TIMESTAMPING_SOFTWARE; info->phc_index = -1; - return 0; +out: + if (real_dev) + dev_put(real_dev); + return ret; } static const struct ethtool_ops bond_ethtool_ops = { -- 2.35.1