Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933069AbbDUPkR (ORCPT ); Tue, 21 Apr 2015 11:40:17 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:57797 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932686AbbDUPfW (ORCPT ); Tue, 21 Apr 2015 11:35:22 -0400 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Cong Wang , "David S. Miller" , Luis Henriques Subject: [PATCH 3.16.y-ckt 130/144] net: use for_each_netdev_safe() in rtnl_group_changelink() Date: Tue, 21 Apr 2015 16:31:55 +0100 Message-Id: <1429630329-21748-131-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1429630329-21748-1-git-send-email-luis.henriques@canonical.com> References: <1429630329-21748-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.16 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4782 Lines: 105 3.16.7-ckt10 -stable review patch. If anyone has any objections, please let me know. ------------------ From: WANG Cong commit d079535d5e1bf5e2e7c856bae2483414ea21e137 upstream. In case we move the whole dev group to another netns, we should call for_each_netdev_safe(), otherwise we get a soft lockup: NMI watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [ip:798] irq event stamp: 255424 hardirqs last enabled at (255423): [] restore_args+0x0/0x30 hardirqs last disabled at (255424): [] apic_timer_interrupt+0x6a/0x80 softirqs last enabled at (255422): [] __do_softirq+0x2c1/0x3a9 softirqs last disabled at (255417): [] irq_exit+0x41/0x95 CPU: 0 PID: 798 Comm: ip Not tainted 4.0.0-rc4+ #881 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 task: ffff8800d1b88000 ti: ffff880119530000 task.ti: ffff880119530000 RIP: 0010:[] [] debug_lockdep_rcu_enabled+0x28/0x30 RSP: 0018:ffff880119533778 EFLAGS: 00000246 RAX: ffff8800d1b88000 RBX: 0000000000000002 RCX: 0000000000000038 RDX: 0000000000000000 RSI: ffff8800d1b888c8 RDI: ffff8800d1b888c8 RBP: ffff880119533778 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 000000000000b5c2 R12: 0000000000000246 R13: ffff880119533708 R14: 00000000001d5a40 R15: ffff88011a7d5a40 FS: 00007fc01315f740(0000) GS:ffff88011a600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 00007f367a120988 CR3: 000000011849c000 CR4: 00000000000007f0 Stack: ffff880119533798 ffffffff811ac868 ffffffff811ac831 ffffffff811ac828 ffff8801195337c8 ffffffff811ac8c9 ffff8801195339b0 ffff8801197633e0 0000000000000000 ffff8801195339b0 ffff8801195337d8 ffffffff811ad2d7 Call Trace: [] rcu_read_lock+0x37/0x6e [] ? rcu_read_unlock+0x5f/0x5f [] ? rcu_read_unlock+0x56/0x5f [] __fget+0x2a/0x7a [] fget+0x13/0x15 [] proc_ns_fget+0xe/0x38 [] get_net_ns_by_fd+0x11/0x59 [] rtnl_link_get_net+0x33/0x3e [] do_setlink+0x73/0x87b [] ? trace_hardirqs_off+0xd/0xf [] ? retint_restore_args+0xe/0xe [] rtnl_newlink+0x40c/0x699 [] ? rtnl_newlink+0xeb/0x699 [] ? _raw_spin_unlock+0x28/0x33 [] ? security_capable+0x18/0x1a [] ? ns_capable+0x4d/0x65 [] rtnetlink_rcv_msg+0x181/0x194 [] ? rtnl_lock+0x17/0x19 [] ? rtnl_lock+0x17/0x19 [] ? __rtnl_unlock+0x17/0x17 [] netlink_rcv_skb+0x4d/0x93 [] rtnetlink_rcv+0x26/0x2d [] netlink_unicast+0xcb/0x150 [] netlink_sendmsg+0x501/0x523 [] ? might_fault+0x59/0xa9 [] ? copy_from_user+0x2a/0x2c [] sock_sendmsg+0x34/0x3c [] ___sys_sendmsg+0x1b8/0x255 [] ? handle_pte_fault+0xbd5/0xd4a [] ? native_sched_clock+0x35/0x37 [] ? sched_clock_local+0x12/0x72 [] ? sched_clock_cpu+0x9e/0xb7 [] ? rcu_read_lock_held+0x3b/0x3d [] ? __fcheck_files+0x4c/0x58 [] ? __fget_light+0x2d/0x52 [] __sys_sendmsg+0x42/0x60 [] SyS_sendmsg+0x12/0x1c [] system_call_fastpath+0x12/0x17 Fixes: e7ed828f10bd8 ("netlink: support setting devgroup parameters") Signed-off-by: Cong Wang Signed-off-by: David S. Miller Signed-off-by: Luis Henriques --- net/core/rtnetlink.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index b1e79ca03fa0..0d2119ff2875 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -1859,10 +1859,10 @@ static int rtnl_group_changelink(const struct sk_buff *skb, struct ifinfomsg *ifm, struct nlattr **tb) { - struct net_device *dev; + struct net_device *dev, *aux; int err; - for_each_netdev(net, dev) { + for_each_netdev_safe(net, dev, aux) { if (dev->group == group) { err = do_setlink(skb, dev, ifm, tb, NULL, 0); if (err < 0) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/