* Re: INFO: task hung in bpf_exit_net [not found] <001a1143fd00a8cc790560b0b552@google.com> @ 2017-12-19 12:47 ` Dmitry Vyukov 2017-12-19 16:21 ` Xin Long 2017-12-19 18:20 ` David Ahern 0 siblings, 2 replies; 9+ messages in thread From: Dmitry Vyukov @ 2017-12-19 12:47 UTC (permalink / raw) To: syzbot Cc: LKML, Ingo Molnar, Peter Zijlstra, syzkaller-bugs, David Miller, dsahern, Florian Westphal, Daniel Borkmann, Xin Long, jakub.kicinski, mschiffer, Vladislav Yasevich, Jiri Benc, netdev On Tue, Dec 19, 2017 at 1:36 PM, syzbot <bot+21b498fc12cf2041655f8e1eeae0733807d794b3@syzkaller.appspotmail.com> wrote: > Hello, > > syzkaller hit the following crash on > 7ceb97a071e80f1b5e4cd5a36de135612a836388 > git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/master > compiler: gcc (GCC) 7.1.1 20170620 > .config is attached > Raw console output is attached. > > Unfortunately, I don't have any reproducer for this bug yet. > > > sctp: sctp_transport_update_pmtu: Reported pmtu 508 too low, using default > minimum of 512 > INFO: task kworker/u4:0:5 blocked for more than 120 seconds. > Not tainted 4.15.0-rc2-next-20171205+ #59 > "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. > kworker/u4:0 D15808 5 2 0x80000000 > Workqueue: netns cleanup_net > Call Trace: > context_switch kernel/sched/core.c:2800 [inline] > __schedule+0x8eb/0x2060 kernel/sched/core.c:3376 > schedule+0xf5/0x430 kernel/sched/core.c:3435 > schedule_preempt_disabled+0x10/0x20 kernel/sched/core.c:3493 > __mutex_lock_common kernel/locking/mutex.c:833 [inline] > __mutex_lock+0xaad/0x1a80 kernel/locking/mutex.c:893 > mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 > rtnl_lock+0x17/0x20 net/core/rtnetlink.c:74 > tc_action_net_exit include/net/act_api.h:125 [inline] > bpf_exit_net+0x1a2/0x340 net/sched/act_bpf.c:408 > ops_exit_list.isra.6+0xae/0x150 net/core/net_namespace.c:142 > cleanup_net+0x5c7/0xb60 net/core/net_namespace.c:484 > process_one_work+0xbfd/0x1bc0 kernel/workqueue.c:2113 > worker_thread+0x223/0x1990 kernel/workqueue.c:2247 > kthread+0x37a/0x440 kernel/kthread.c:238 > ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:517 > > Showing all locks held in the system: > 4 locks held by kworker/u4:0/5: > #0: ((wq_completion)"%s""netns"){+.+.}, at: [<00000000b9f061a2>] > __write_once_size include/linux/compiler.h:212 [inline] > #0: ((wq_completion)"%s""netns"){+.+.}, at: [<00000000b9f061a2>] > atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] > #0: ((wq_completion)"%s""netns"){+.+.}, at: [<00000000b9f061a2>] > atomic_long_set include/asm-generic/atomic-long.h:57 [inline] > #0: ((wq_completion)"%s""netns"){+.+.}, at: [<00000000b9f061a2>] > set_work_data kernel/workqueue.c:619 [inline] > #0: ((wq_completion)"%s""netns"){+.+.}, at: [<00000000b9f061a2>] > set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] > #0: ((wq_completion)"%s""netns"){+.+.}, at: [<00000000b9f061a2>] > process_one_work+0xad4/0x1bc0 kernel/workqueue.c:2084 > #1: (net_cleanup_work){+.+.}, at: [<000000006c7c48a3>] > process_one_work+0xb2f/0x1bc0 kernel/workqueue.c:2088 > #2: (net_mutex){+.+.}, at: [<00000000bf4709f3>] cleanup_net+0x247/0xb60 > net/core/net_namespace.c:450 > #3: (rtnl_mutex){+.+.}, at: [<0000000053390f0b>] rtnl_lock+0x17/0x20 > net/core/rtnetlink.c:74 > 3 locks held by kworker/1:0/17: > #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000b9f061a2>] > __write_once_size include/linux/compiler.h:212 [inline] > #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000b9f061a2>] > atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] > #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000b9f061a2>] > atomic_long_set include/asm-generic/atomic-long.h:57 [inline] > #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000b9f061a2>] > set_work_data kernel/workqueue.c:619 [inline] > #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000b9f061a2>] > set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] > #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000b9f061a2>] > process_one_work+0xad4/0x1bc0 kernel/workqueue.c:2084 > #1: ((addr_chk_work).work){+.+.}, at: [<000000006c7c48a3>] > process_one_work+0xb2f/0x1bc0 kernel/workqueue.c:2088 > #2: (rtnl_mutex){+.+.}, at: [<0000000053390f0b>] rtnl_lock+0x17/0x20 > net/core/rtnetlink.c:74 > 2 locks held by khungtaskd/675: > #0: (rcu_read_lock){....}, at: [<00000000587c8471>] > check_hung_uninterruptible_tasks kernel/hung_task.c:175 [inline] > #0: (rcu_read_lock){....}, at: [<00000000587c8471>] watchdog+0x1c5/0xd60 > kernel/hung_task.c:249 > #1: (tasklist_lock){.+.+}, at: [<000000005288685e>] > debug_show_all_locks+0xd3/0x400 kernel/locking/lockdep.c:4554 > 1 lock held by rsyslogd/2974: > #0: (&f->f_pos_lock){+.+.}, at: [<0000000011e00499>] > __fdget_pos+0x131/0x1a0 fs/file.c:770 > 2 locks held by getty/3056: > #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] > ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 > #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] > n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 > 2 locks held by getty/3057: > #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] > ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 > #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] > n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 > 2 locks held by getty/3058: > #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] > ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 > #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] > n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 > 2 locks held by getty/3059: > #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] > ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 > #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] > n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 > 2 locks held by getty/3060: > #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] > ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 > #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] > n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 > 2 locks held by getty/3061: > #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] > ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 > #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] > n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 > 2 locks held by getty/3062: > #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] > ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 > #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] > n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 > > ============================================= > > NMI backtrace for cpu 0 > CPU: 0 PID: 675 Comm: khungtaskd Not tainted 4.15.0-rc2-next-20171205+ #59 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS > Google 01/01/2011 > Call Trace: > __dump_stack lib/dump_stack.c:17 [inline] > dump_stack+0x194/0x257 lib/dump_stack.c:53 > nmi_cpu_backtrace+0x1d2/0x210 lib/nmi_backtrace.c:103 > nmi_trigger_cpumask_backtrace+0x122/0x180 lib/nmi_backtrace.c:62 > arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 > trigger_all_cpu_backtrace include/linux/nmi.h:138 [inline] > check_hung_task kernel/hung_task.c:132 [inline] > check_hung_uninterruptible_tasks kernel/hung_task.c:190 [inline] > watchdog+0x90c/0xd60 kernel/hung_task.c:249 > kthread+0x37a/0x440 kernel/kthread.c:238 > ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:517 > Sending NMI from CPU 0 to CPUs 1: > NMI backtrace for cpu 1 > CPU: 1 PID: 13156 Comm: syz-executor7 Not tainted 4.15.0-rc2-next-20171205+ > #59 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS > Google 01/01/2011 > task: 000000005209c120 task.stack: 00000000ffaab0e8 > RIP: 0010:inb arch/x86/include/asm/io.h:348 [inline] > RIP: 0010:io_serial_in+0x6b/0x90 drivers/tty/serial/8250/8250_port.c:434 > RSP: 0018:ffff8801c0a16e70 EFLAGS: 00000002 > RAX: dffffc0000000000 RBX: 00000000000003fd RCX: 0000000000000000 > RDX: 00000000000003fd RSI: ffffc90003745000 RDI: ffffffff87cf1a40 > RBP: ffff8801c0a16e80 R08: 0000000000000005 R09: 000000000000000c > R10: 0000000000000000 R11: ffffffff8748dd20 R12: ffffffff87cf1a00 > R13: 0000000000000020 R14: fffffbfff0f9e387 R15: fffffbfff0f9e34a > FS: 00007f6d52e3f700(0000) GS:ffff8801db500000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 000000c42005de80 CR3: 00000001c368a000 CR4: 00000000001406e0 > DR0: 0000000020000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 > Call Trace: > serial_in drivers/tty/serial/8250/8250.h:111 [inline] > wait_for_xmitr+0x93/0x1e0 drivers/tty/serial/8250/8250_port.c:2033 > serial8250_console_putchar+0x1f/0x60 > drivers/tty/serial/8250/8250_port.c:3170 > uart_console_write+0xac/0xe0 drivers/tty/serial/serial_core.c:1858 > serial8250_console_write+0x647/0xa20 > drivers/tty/serial/8250/8250_port.c:3236 > univ8250_console_write+0x5f/0x70 drivers/tty/serial/8250/8250_core.c:590 > call_console_drivers kernel/printk/printk.c:1574 [inline] > console_unlock+0x788/0xd70 kernel/printk/printk.c:2233 > vprintk_emit+0x4ad/0x590 kernel/printk/printk.c:1757 > vprintk_default+0x28/0x30 kernel/printk/printk.c:1796 > vprintk_func+0x57/0xc0 kernel/printk/printk_safe.c:379 > printk+0xaa/0xca kernel/printk/printk.c:1829 > nla_parse+0x374/0x3d0 lib/nlattr.c:257 > nlmsg_parse include/net/netlink.h:398 [inline] > nl80211_dump_wiphy_parse.isra.37.constprop.83+0x138/0x5c0 > net/wireless/nl80211.c:1920 > nl80211_dump_interface+0x596/0x820 net/wireless/nl80211.c:2660 > genl_lock_dumpit+0x68/0x90 net/netlink/genetlink.c:480 > netlink_dump+0x48c/0xce0 net/netlink/af_netlink.c:2186 > __netlink_dump_start+0x4f0/0x6d0 net/netlink/af_netlink.c:2283 > genl_family_rcv_msg+0xd27/0xfc0 net/netlink/genetlink.c:548 > genl_rcv_msg+0xb2/0x140 net/netlink/genetlink.c:624 > netlink_rcv_skb+0x216/0x440 net/netlink/af_netlink.c:2405 > genl_rcv+0x28/0x40 net/netlink/genetlink.c:635 > netlink_unicast_kernel net/netlink/af_netlink.c:1272 [inline] > netlink_unicast+0x4e8/0x6f0 net/netlink/af_netlink.c:1298 > netlink_sendmsg+0xa4a/0xe70 net/netlink/af_netlink.c:1861 > sock_sendmsg_nosec net/socket.c:636 [inline] > sock_sendmsg+0xca/0x110 net/socket.c:646 > sock_write_iter+0x320/0x5e0 net/socket.c:915 > call_write_iter include/linux/fs.h:1776 [inline] > new_sync_write fs/read_write.c:469 [inline] > __vfs_write+0x68a/0x970 fs/read_write.c:482 > vfs_write+0x18f/0x510 fs/read_write.c:544 > SYSC_write fs/read_write.c:589 [inline] > SyS_write+0xef/0x220 fs/read_write.c:581 > entry_SYSCALL_64_fastpath+0x1f/0x96 > RIP: 0033:0x4529d9 > RSP: 002b:00007f6d52e3ec58 EFLAGS: 00000212 ORIG_RAX: 0000000000000001 > RAX: ffffffffffffffda RBX: 00007f6d52e3f700 RCX: 00000000004529d9 > RDX: 0000000000000024 RSI: 0000000020454000 RDI: 0000000000000016 > RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000000 > R13: 0000000000a6f7ff R14: 00007f6d52e3f9c0 R15: 0000000000000000 > Code: 24 d9 00 00 00 49 8d 7c 24 40 48 b8 00 00 00 00 00 fc ff df 48 89 fa > 48 c1 ea 03 d3 e3 80 3c 02 00 75 17 41 03 5c 24 40 89 da ec <5b> 0f b6 c0 41 > 5c 5d c3 e8 38 b0 18 ff eb c2 e8 91 b0 18 ff eb > > > --- > This bug is generated by a dumb bot. It may contain errors. > See https://goo.gl/tpsmEJ for details. > Direct all questions to syzkaller@googlegroups.com. > Please credit me with: Reported-by: syzbot <syzkaller@googlegroups.com> > > syzbot will keep track of this bug report. > Once a fix for this bug is merged into any tree, reply to this email with: > #syz fix: exact-commit-title > To mark this as a duplicate of another syzbot report, please reply with: > #syz dup: exact-subject-of-another-report > If it's a one-off invalid bug report, please reply with: > #syz invalid > Note: if the crash happens again, it will cause creation of a new bug > report. > Note: all commands must start from beginning of the line in the email body. > > -- > You received this message because you are subscribed to the Google Groups > "syzkaller-bugs" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to syzkaller-bugs+unsubscribe@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/syzkaller-bugs/001a1143fd00a8cc790560b0b552%40google.com. > For more options, visit https://groups.google.com/d/optout. This looks like +rtnetlink issue. ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: INFO: task hung in bpf_exit_net 2017-12-19 12:47 ` INFO: task hung in bpf_exit_net Dmitry Vyukov @ 2017-12-19 16:21 ` Xin Long 2017-12-19 18:20 ` David Ahern 1 sibling, 0 replies; 9+ messages in thread From: Xin Long @ 2017-12-19 16:21 UTC (permalink / raw) To: Dmitry Vyukov Cc: syzbot, LKML, Ingo Molnar, Peter Zijlstra, syzkaller-bugs, David Miller, David Ahern, Florian Westphal, Daniel Borkmann, jakub.kicinski, mschiffer, Vladislav Yasevich, Jiri Benc, netdev On Tue, Dec 19, 2017 at 8:47 PM, Dmitry Vyukov <dvyukov@google.com> wrote: > On Tue, Dec 19, 2017 at 1:36 PM, syzbot > <bot+21b498fc12cf2041655f8e1eeae0733807d794b3@syzkaller.appspotmail.com> > wrote: >> Hello, >> >> syzkaller hit the following crash on >> 7ceb97a071e80f1b5e4cd5a36de135612a836388 >> git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/master >> compiler: gcc (GCC) 7.1.1 20170620 >> .config is attached >> Raw console output is attached. >> >> Unfortunately, I don't have any reproducer for this bug yet. >> >> >> sctp: sctp_transport_update_pmtu: Reported pmtu 508 too low, using default >> minimum of 512 >> INFO: task kworker/u4:0:5 blocked for more than 120 seconds. >> Not tainted 4.15.0-rc2-next-20171205+ #59 >> "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. >> kworker/u4:0 D15808 5 2 0x80000000 >> Workqueue: netns cleanup_net >> Call Trace: >> context_switch kernel/sched/core.c:2800 [inline] >> __schedule+0x8eb/0x2060 kernel/sched/core.c:3376 >> schedule+0xf5/0x430 kernel/sched/core.c:3435 >> schedule_preempt_disabled+0x10/0x20 kernel/sched/core.c:3493 >> __mutex_lock_common kernel/locking/mutex.c:833 [inline] >> __mutex_lock+0xaad/0x1a80 kernel/locking/mutex.c:893 >> mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 >> rtnl_lock+0x17/0x20 net/core/rtnetlink.c:74 >> tc_action_net_exit include/net/act_api.h:125 [inline] >> bpf_exit_net+0x1a2/0x340 net/sched/act_bpf.c:408 >> ops_exit_list.isra.6+0xae/0x150 net/core/net_namespace.c:142 >> cleanup_net+0x5c7/0xb60 net/core/net_namespace.c:484 >> process_one_work+0xbfd/0x1bc0 kernel/workqueue.c:2113 >> worker_thread+0x223/0x1990 kernel/workqueue.c:2247 >> kthread+0x37a/0x440 kernel/kthread.c:238 >> ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:517 >> [...] >> Call Trace: >> serial_in drivers/tty/serial/8250/8250.h:111 [inline] >> wait_for_xmitr+0x93/0x1e0 drivers/tty/serial/8250/8250_port.c:2033 I saw this call trace on both 'bpf_exit_net task hung' and 'cleanup_net task hung'. Note when cpu is here, it's still holding the rtnl_lock in these 2 cases, one is in nl80211_dump_interface(), and the other one is in dev_ioctl(). I noticed this patch: commit 54f19b4a679149130f78413c421a5780e90a9d0a Author: Jiri Olsa <jolsa@kernel.org> Date: Wed Sep 21 16:43:15 2016 +0200 tty/serial/8250: Touch NMI watchdog in wait_for_xmitr It means in early time, watchdog timeout can be triggered here, And this patch was to fix it by restarting NMI watchdog timeout with calling touch_nmi_watchdog(). But this patch missed that it's still holding the rtnl_lock(), other threads may timeout on watchdog when trying to acquire rtnl_lock(). >> serial8250_console_putchar+0x1f/0x60 >> drivers/tty/serial/8250/8250_port.c:3170 >> uart_console_write+0xac/0xe0 drivers/tty/serial/serial_core.c:1858 >> serial8250_console_write+0x647/0xa20 >> drivers/tty/serial/8250/8250_port.c:3236 >> univ8250_console_write+0x5f/0x70 drivers/tty/serial/8250/8250_core.c:590 >> call_console_drivers kernel/printk/printk.c:1574 [inline] >> console_unlock+0x788/0xd70 kernel/printk/printk.c:2233 >> vprintk_emit+0x4ad/0x590 kernel/printk/printk.c:1757 >> vprintk_default+0x28/0x30 kernel/printk/printk.c:1796 >> vprintk_func+0x57/0xc0 kernel/printk/printk_safe.c:379 >> printk+0xaa/0xca kernel/printk/printk.c:1829 >> nla_parse+0x374/0x3d0 lib/nlattr.c:257 >> nlmsg_parse include/net/netlink.h:398 [inline] >> nl80211_dump_wiphy_parse.isra.37.constprop.83+0x138/0x5c0 >> net/wireless/nl80211.c:1920 >> nl80211_dump_interface+0x596/0x820 net/wireless/nl80211.c:2660 >> genl_lock_dumpit+0x68/0x90 net/netlink/genetlink.c:480 >> netlink_dump+0x48c/0xce0 net/netlink/af_netlink.c:2186 >> __netlink_dump_start+0x4f0/0x6d0 net/netlink/af_netlink.c:2283 >> genl_family_rcv_msg+0xd27/0xfc0 net/netlink/genetlink.c:548 >> genl_rcv_msg+0xb2/0x140 net/netlink/genetlink.c:624 >> netlink_rcv_skb+0x216/0x440 net/netlink/af_netlink.c:2405 >> genl_rcv+0x28/0x40 net/netlink/genetlink.c:635 >> netlink_unicast_kernel net/netlink/af_netlink.c:1272 [inline] >> netlink_unicast+0x4e8/0x6f0 net/netlink/af_netlink.c:1298 >> netlink_sendmsg+0xa4a/0xe70 net/netlink/af_netlink.c:1861 >> sock_sendmsg_nosec net/socket.c:636 [inline] >> sock_sendmsg+0xca/0x110 net/socket.c:646 >> sock_write_iter+0x320/0x5e0 net/socket.c:915 >> call_write_iter include/linux/fs.h:1776 [inline] >> new_sync_write fs/read_write.c:469 [inline] >> __vfs_write+0x68a/0x970 fs/read_write.c:482 >> vfs_write+0x18f/0x510 fs/read_write.c:544 >> SYSC_write fs/read_write.c:589 [inline] >> SyS_write+0xef/0x220 fs/read_write.c:581 >> entry_SYSCALL_64_fastpath+0x1f/0x96 >> RIP: 0033:0x4529d9 >> RSP: 002b:00007f6d52e3ec58 EFLAGS: 00000212 ORIG_RAX: 0000000000000001 >> RAX: ffffffffffffffda RBX: 00007f6d52e3f700 RCX: 00000000004529d9 >> RDX: 0000000000000024 RSI: 0000000020454000 RDI: 0000000000000016 >> RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 >> R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000000 >> R13: 0000000000a6f7ff R14: 00007f6d52e3f9c0 R15: 0000000000000000 >> Code: 24 d9 00 00 00 49 8d 7c 24 40 48 b8 00 00 00 00 00 fc ff df 48 89 fa >> 48 c1 ea 03 d3 e3 80 3c 02 00 75 17 41 03 5c 24 40 89 da ec <5b> 0f b6 c0 41 >> 5c 5d c3 e8 38 b0 18 ff eb c2 e8 91 b0 18 ff eb >> >> >> --- >> This bug is generated by a dumb bot. It may contain errors. >> See https://goo.gl/tpsmEJ for details. >> Direct all questions to syzkaller@googlegroups.com. >> Please credit me with: Reported-by: syzbot <syzkaller@googlegroups.com> >> >> syzbot will keep track of this bug report. >> Once a fix for this bug is merged into any tree, reply to this email with: >> #syz fix: exact-commit-title >> To mark this as a duplicate of another syzbot report, please reply with: >> #syz dup: exact-subject-of-another-report >> If it's a one-off invalid bug report, please reply with: >> #syz invalid >> Note: if the crash happens again, it will cause creation of a new bug >> report. >> Note: all commands must start from beginning of the line in the email body. >> >> -- >> You received this message because you are subscribed to the Google Groups >> "syzkaller-bugs" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to syzkaller-bugs+unsubscribe@googlegroups.com. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/syzkaller-bugs/001a1143fd00a8cc790560b0b552%40google.com. >> For more options, visit https://groups.google.com/d/optout. > > > This looks like +rtnetlink issue. ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: INFO: task hung in bpf_exit_net 2017-12-19 12:47 ` INFO: task hung in bpf_exit_net Dmitry Vyukov 2017-12-19 16:21 ` Xin Long @ 2017-12-19 18:20 ` David Ahern 2017-12-22 10:58 ` Dmitry Vyukov 1 sibling, 1 reply; 9+ messages in thread From: David Ahern @ 2017-12-19 18:20 UTC (permalink / raw) To: Dmitry Vyukov, syzbot Cc: LKML, Ingo Molnar, Peter Zijlstra, syzkaller-bugs, David Miller, Florian Westphal, Daniel Borkmann, Xin Long, jakub.kicinski, mschiffer, Vladislav Yasevich, Jiri Benc, netdev On 12/19/17 5:47 AM, Dmitry Vyukov wrote: > On Tue, Dec 19, 2017 at 1:36 PM, syzbot > <bot+21b498fc12cf2041655f8e1eeae0733807d794b3@syzkaller.appspotmail.com> > wrote: >> Hello, >> >> syzkaller hit the following crash on >> 7ceb97a071e80f1b5e4cd5a36de135612a836388 >> git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/master >> compiler: gcc (GCC) 7.1.1 20170620 >> .config is attached >> Raw console output is attached. >> >> Unfortunately, I don't have any reproducer for this bug yet. >> >> >> sctp: sctp_transport_update_pmtu: Reported pmtu 508 too low, using default >> minimum of 512 >> INFO: task kworker/u4:0:5 blocked for more than 120 seconds. >> Not tainted 4.15.0-rc2-next-20171205+ #59 >> "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. >> kworker/u4:0 D15808 5 2 0x80000000 >> Workqueue: netns cleanup_net >> Call Trace: >> context_switch kernel/sched/core.c:2800 [inline] >> __schedule+0x8eb/0x2060 kernel/sched/core.c:3376 >> schedule+0xf5/0x430 kernel/sched/core.c:3435 >> schedule_preempt_disabled+0x10/0x20 kernel/sched/core.c:3493 >> __mutex_lock_common kernel/locking/mutex.c:833 [inline] >> __mutex_lock+0xaad/0x1a80 kernel/locking/mutex.c:893 >> mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 >> rtnl_lock+0x17/0x20 net/core/rtnetlink.c:74 >> tc_action_net_exit include/net/act_api.h:125 [inline] >> bpf_exit_net+0x1a2/0x340 net/sched/act_bpf.c:408 >> ops_exit_list.isra.6+0xae/0x150 net/core/net_namespace.c:142 >> cleanup_net+0x5c7/0xb60 net/core/net_namespace.c:484 >> process_one_work+0xbfd/0x1bc0 kernel/workqueue.c:2113 >> worker_thread+0x223/0x1990 kernel/workqueue.c:2247 >> kthread+0x37a/0x440 kernel/kthread.c:238 >> ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:517 >> >> Showing all locks held in the system: >> 4 locks held by kworker/u4:0/5: >> #0: ((wq_completion)"%s""netns"){+.+.}, at: [<00000000b9f061a2>] >> __write_once_size include/linux/compiler.h:212 [inline] >> #0: ((wq_completion)"%s""netns"){+.+.}, at: [<00000000b9f061a2>] >> atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] >> #0: ((wq_completion)"%s""netns"){+.+.}, at: [<00000000b9f061a2>] >> atomic_long_set include/asm-generic/atomic-long.h:57 [inline] >> #0: ((wq_completion)"%s""netns"){+.+.}, at: [<00000000b9f061a2>] >> set_work_data kernel/workqueue.c:619 [inline] >> #0: ((wq_completion)"%s""netns"){+.+.}, at: [<00000000b9f061a2>] >> set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] >> #0: ((wq_completion)"%s""netns"){+.+.}, at: [<00000000b9f061a2>] >> process_one_work+0xad4/0x1bc0 kernel/workqueue.c:2084 >> #1: (net_cleanup_work){+.+.}, at: [<000000006c7c48a3>] >> process_one_work+0xb2f/0x1bc0 kernel/workqueue.c:2088 >> #2: (net_mutex){+.+.}, at: [<00000000bf4709f3>] cleanup_net+0x247/0xb60 >> net/core/net_namespace.c:450 >> #3: (rtnl_mutex){+.+.}, at: [<0000000053390f0b>] rtnl_lock+0x17/0x20 >> net/core/rtnetlink.c:74 >> 3 locks held by kworker/1:0/17: >> #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000b9f061a2>] >> __write_once_size include/linux/compiler.h:212 [inline] >> #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000b9f061a2>] >> atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] >> #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000b9f061a2>] >> atomic_long_set include/asm-generic/atomic-long.h:57 [inline] >> #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000b9f061a2>] >> set_work_data kernel/workqueue.c:619 [inline] >> #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000b9f061a2>] >> set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] >> #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000b9f061a2>] >> process_one_work+0xad4/0x1bc0 kernel/workqueue.c:2084 >> #1: ((addr_chk_work).work){+.+.}, at: [<000000006c7c48a3>] >> process_one_work+0xb2f/0x1bc0 kernel/workqueue.c:2088 >> #2: (rtnl_mutex){+.+.}, at: [<0000000053390f0b>] rtnl_lock+0x17/0x20 >> net/core/rtnetlink.c:74 >> 2 locks held by khungtaskd/675: >> #0: (rcu_read_lock){....}, at: [<00000000587c8471>] >> check_hung_uninterruptible_tasks kernel/hung_task.c:175 [inline] >> #0: (rcu_read_lock){....}, at: [<00000000587c8471>] watchdog+0x1c5/0xd60 >> kernel/hung_task.c:249 >> #1: (tasklist_lock){.+.+}, at: [<000000005288685e>] >> debug_show_all_locks+0xd3/0x400 kernel/locking/lockdep.c:4554 >> 1 lock held by rsyslogd/2974: >> #0: (&f->f_pos_lock){+.+.}, at: [<0000000011e00499>] >> __fdget_pos+0x131/0x1a0 fs/file.c:770 >> 2 locks held by getty/3056: >> #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] >> ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 >> #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] >> n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 >> 2 locks held by getty/3057: >> #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] >> ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 >> #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] >> n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 >> 2 locks held by getty/3058: >> #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] >> ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 >> #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] >> n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 >> 2 locks held by getty/3059: >> #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] >> ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 >> #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] >> n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 >> 2 locks held by getty/3060: >> #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] >> ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 >> #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] >> n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 >> 2 locks held by getty/3061: >> #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] >> ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 >> #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] >> n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 >> 2 locks held by getty/3062: >> #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] >> ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 >> #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] >> n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 >> >> ============================================= >> >> NMI backtrace for cpu 0 >> CPU: 0 PID: 675 Comm: khungtaskd Not tainted 4.15.0-rc2-next-20171205+ #59 >> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS >> Google 01/01/2011 >> Call Trace: >> __dump_stack lib/dump_stack.c:17 [inline] >> dump_stack+0x194/0x257 lib/dump_stack.c:53 >> nmi_cpu_backtrace+0x1d2/0x210 lib/nmi_backtrace.c:103 >> nmi_trigger_cpumask_backtrace+0x122/0x180 lib/nmi_backtrace.c:62 >> arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 >> trigger_all_cpu_backtrace include/linux/nmi.h:138 [inline] >> check_hung_task kernel/hung_task.c:132 [inline] >> check_hung_uninterruptible_tasks kernel/hung_task.c:190 [inline] >> watchdog+0x90c/0xd60 kernel/hung_task.c:249 >> kthread+0x37a/0x440 kernel/kthread.c:238 >> ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:517 >> Sending NMI from CPU 0 to CPUs 1: >> NMI backtrace for cpu 1 >> CPU: 1 PID: 13156 Comm: syz-executor7 Not tainted 4.15.0-rc2-next-20171205+ >> #59 >> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS >> Google 01/01/2011 >> task: 000000005209c120 task.stack: 00000000ffaab0e8 >> RIP: 0010:inb arch/x86/include/asm/io.h:348 [inline] >> RIP: 0010:io_serial_in+0x6b/0x90 drivers/tty/serial/8250/8250_port.c:434 >> RSP: 0018:ffff8801c0a16e70 EFLAGS: 00000002 >> RAX: dffffc0000000000 RBX: 00000000000003fd RCX: 0000000000000000 >> RDX: 00000000000003fd RSI: ffffc90003745000 RDI: ffffffff87cf1a40 >> RBP: ffff8801c0a16e80 R08: 0000000000000005 R09: 000000000000000c >> R10: 0000000000000000 R11: ffffffff8748dd20 R12: ffffffff87cf1a00 >> R13: 0000000000000020 R14: fffffbfff0f9e387 R15: fffffbfff0f9e34a >> FS: 00007f6d52e3f700(0000) GS:ffff8801db500000(0000) knlGS:0000000000000000 >> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 >> CR2: 000000c42005de80 CR3: 00000001c368a000 CR4: 00000000001406e0 >> DR0: 0000000020000000 DR1: 0000000000000000 DR2: 0000000000000000 >> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 >> Call Trace: >> serial_in drivers/tty/serial/8250/8250.h:111 [inline] >> wait_for_xmitr+0x93/0x1e0 drivers/tty/serial/8250/8250_port.c:2033 >> serial8250_console_putchar+0x1f/0x60 >> drivers/tty/serial/8250/8250_port.c:3170 >> uart_console_write+0xac/0xe0 drivers/tty/serial/serial_core.c:1858 >> serial8250_console_write+0x647/0xa20 >> drivers/tty/serial/8250/8250_port.c:3236 >> univ8250_console_write+0x5f/0x70 drivers/tty/serial/8250/8250_core.c:590 >> call_console_drivers kernel/printk/printk.c:1574 [inline] >> console_unlock+0x788/0xd70 kernel/printk/printk.c:2233 >> vprintk_emit+0x4ad/0x590 kernel/printk/printk.c:1757 >> vprintk_default+0x28/0x30 kernel/printk/printk.c:1796 >> vprintk_func+0x57/0xc0 kernel/printk/printk_safe.c:379 >> printk+0xaa/0xca kernel/printk/printk.c:1829 >> nla_parse+0x374/0x3d0 lib/nlattr.c:257 >> nlmsg_parse include/net/netlink.h:398 [inline] >> nl80211_dump_wiphy_parse.isra.37.constprop.83+0x138/0x5c0 >> net/wireless/nl80211.c:1920 >> nl80211_dump_interface+0x596/0x820 net/wireless/nl80211.c:2660 >> genl_lock_dumpit+0x68/0x90 net/netlink/genetlink.c:480 >> netlink_dump+0x48c/0xce0 net/netlink/af_netlink.c:2186 >> __netlink_dump_start+0x4f0/0x6d0 net/netlink/af_netlink.c:2283 >> genl_family_rcv_msg+0xd27/0xfc0 net/netlink/genetlink.c:548 >> genl_rcv_msg+0xb2/0x140 net/netlink/genetlink.c:624 >> netlink_rcv_skb+0x216/0x440 net/netlink/af_netlink.c:2405 >> genl_rcv+0x28/0x40 net/netlink/genetlink.c:635 >> netlink_unicast_kernel net/netlink/af_netlink.c:1272 [inline] >> netlink_unicast+0x4e8/0x6f0 net/netlink/af_netlink.c:1298 >> netlink_sendmsg+0xa4a/0xe70 net/netlink/af_netlink.c:1861 >> sock_sendmsg_nosec net/socket.c:636 [inline] >> sock_sendmsg+0xca/0x110 net/socket.c:646 >> sock_write_iter+0x320/0x5e0 net/socket.c:915 >> call_write_iter include/linux/fs.h:1776 [inline] >> new_sync_write fs/read_write.c:469 [inline] >> __vfs_write+0x68a/0x970 fs/read_write.c:482 >> vfs_write+0x18f/0x510 fs/read_write.c:544 >> SYSC_write fs/read_write.c:589 [inline] >> SyS_write+0xef/0x220 fs/read_write.c:581 >> entry_SYSCALL_64_fastpath+0x1f/0x96 >> RIP: 0033:0x4529d9 >> RSP: 002b:00007f6d52e3ec58 EFLAGS: 00000212 ORIG_RAX: 0000000000000001 >> RAX: ffffffffffffffda RBX: 00007f6d52e3f700 RCX: 00000000004529d9 >> RDX: 0000000000000024 RSI: 0000000020454000 RDI: 0000000000000016 >> RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 >> R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000000 >> R13: 0000000000a6f7ff R14: 00007f6d52e3f9c0 R15: 0000000000000000 >> Code: 24 d9 00 00 00 49 8d 7c 24 40 48 b8 00 00 00 00 00 fc ff df 48 89 fa >> 48 c1 ea 03 d3 e3 80 3c 02 00 75 17 41 03 5c 24 40 89 da ec <5b> 0f b6 c0 41 >> 5c 5d c3 e8 38 b0 18 ff eb c2 e8 91 b0 18 ff eb >> >> >> --- >> This bug is generated by a dumb bot. It may contain errors. >> See https://goo.gl/tpsmEJ for details. >> Direct all questions to syzkaller@googlegroups.com. >> Please credit me with: Reported-by: syzbot <syzkaller@googlegroups.com> >> >> syzbot will keep track of this bug report. >> Once a fix for this bug is merged into any tree, reply to this email with: >> #syz fix: exact-commit-title >> To mark this as a duplicate of another syzbot report, please reply with: >> #syz dup: exact-subject-of-another-report >> If it's a one-off invalid bug report, please reply with: >> #syz invalid >> Note: if the crash happens again, it will cause creation of a new bug >> report. >> Note: all commands must start from beginning of the line in the email body. >> >> -- >> You received this message because you are subscribed to the Google Groups >> "syzkaller-bugs" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to syzkaller-bugs+unsubscribe@googlegroups.com. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/syzkaller-bugs/001a1143fd00a8cc790560b0b552%40google.com. >> For more options, visit https://groups.google.com/d/optout. > > > This looks like +rtnetlink issue. > Same with this one, perhaps related to / fixed by: http://patchwork.ozlabs.org/patch/850957/ ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: INFO: task hung in bpf_exit_net 2017-12-19 18:20 ` David Ahern @ 2017-12-22 10:58 ` Dmitry Vyukov 2017-12-22 11:16 ` Marcelo Ricardo Leitner 2017-12-22 18:28 ` Marcelo Ricardo Leitner 0 siblings, 2 replies; 9+ messages in thread From: Dmitry Vyukov @ 2017-12-22 10:58 UTC (permalink / raw) To: David Ahern Cc: syzbot, LKML, Ingo Molnar, Peter Zijlstra, syzkaller-bugs, David Miller, Florian Westphal, Daniel Borkmann, Xin Long, jakub.kicinski, mschiffer, Vladislav Yasevich, Jiri Benc, netdev, Neil Horman, linux-sctp On Tue, Dec 19, 2017 at 7:20 PM, David Ahern <dsahern@gmail.com> wrote: > On 12/19/17 5:47 AM, Dmitry Vyukov wrote: >> On Tue, Dec 19, 2017 at 1:36 PM, syzbot >> <bot+21b498fc12cf2041655f8e1eeae0733807d794b3@syzkaller.appspotmail.com> >> wrote: >>> Hello, >>> >>> syzkaller hit the following crash on >>> 7ceb97a071e80f1b5e4cd5a36de135612a836388 >>> git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/master >>> compiler: gcc (GCC) 7.1.1 20170620 >>> .config is attached >>> Raw console output is attached. >>> >>> Unfortunately, I don't have any reproducer for this bug yet. >>> >>> >>> sctp: sctp_transport_update_pmtu: Reported pmtu 508 too low, using default >>> minimum of 512 >>> INFO: task kworker/u4:0:5 blocked for more than 120 seconds. >>> Not tainted 4.15.0-rc2-next-20171205+ #59 >>> "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. >>> kworker/u4:0 D15808 5 2 0x80000000 >>> Workqueue: netns cleanup_net >>> Call Trace: >>> context_switch kernel/sched/core.c:2800 [inline] >>> __schedule+0x8eb/0x2060 kernel/sched/core.c:3376 >>> schedule+0xf5/0x430 kernel/sched/core.c:3435 >>> schedule_preempt_disabled+0x10/0x20 kernel/sched/core.c:3493 >>> __mutex_lock_common kernel/locking/mutex.c:833 [inline] >>> __mutex_lock+0xaad/0x1a80 kernel/locking/mutex.c:893 >>> mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 >>> rtnl_lock+0x17/0x20 net/core/rtnetlink.c:74 >>> tc_action_net_exit include/net/act_api.h:125 [inline] >>> bpf_exit_net+0x1a2/0x340 net/sched/act_bpf.c:408 >>> ops_exit_list.isra.6+0xae/0x150 net/core/net_namespace.c:142 >>> cleanup_net+0x5c7/0xb60 net/core/net_namespace.c:484 >>> process_one_work+0xbfd/0x1bc0 kernel/workqueue.c:2113 >>> worker_thread+0x223/0x1990 kernel/workqueue.c:2247 >>> kthread+0x37a/0x440 kernel/kthread.c:238 >>> ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:517 >>> >>> Showing all locks held in the system: >>> 4 locks held by kworker/u4:0/5: >>> #0: ((wq_completion)"%s""netns"){+.+.}, at: [<00000000b9f061a2>] >>> __write_once_size include/linux/compiler.h:212 [inline] >>> #0: ((wq_completion)"%s""netns"){+.+.}, at: [<00000000b9f061a2>] >>> atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] >>> #0: ((wq_completion)"%s""netns"){+.+.}, at: [<00000000b9f061a2>] >>> atomic_long_set include/asm-generic/atomic-long.h:57 [inline] >>> #0: ((wq_completion)"%s""netns"){+.+.}, at: [<00000000b9f061a2>] >>> set_work_data kernel/workqueue.c:619 [inline] >>> #0: ((wq_completion)"%s""netns"){+.+.}, at: [<00000000b9f061a2>] >>> set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] >>> #0: ((wq_completion)"%s""netns"){+.+.}, at: [<00000000b9f061a2>] >>> process_one_work+0xad4/0x1bc0 kernel/workqueue.c:2084 >>> #1: (net_cleanup_work){+.+.}, at: [<000000006c7c48a3>] >>> process_one_work+0xb2f/0x1bc0 kernel/workqueue.c:2088 >>> #2: (net_mutex){+.+.}, at: [<00000000bf4709f3>] cleanup_net+0x247/0xb60 >>> net/core/net_namespace.c:450 >>> #3: (rtnl_mutex){+.+.}, at: [<0000000053390f0b>] rtnl_lock+0x17/0x20 >>> net/core/rtnetlink.c:74 >>> 3 locks held by kworker/1:0/17: >>> #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000b9f061a2>] >>> __write_once_size include/linux/compiler.h:212 [inline] >>> #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000b9f061a2>] >>> atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] >>> #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000b9f061a2>] >>> atomic_long_set include/asm-generic/atomic-long.h:57 [inline] >>> #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000b9f061a2>] >>> set_work_data kernel/workqueue.c:619 [inline] >>> #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000b9f061a2>] >>> set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] >>> #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000b9f061a2>] >>> process_one_work+0xad4/0x1bc0 kernel/workqueue.c:2084 >>> #1: ((addr_chk_work).work){+.+.}, at: [<000000006c7c48a3>] >>> process_one_work+0xb2f/0x1bc0 kernel/workqueue.c:2088 >>> #2: (rtnl_mutex){+.+.}, at: [<0000000053390f0b>] rtnl_lock+0x17/0x20 >>> net/core/rtnetlink.c:74 >>> 2 locks held by khungtaskd/675: >>> #0: (rcu_read_lock){....}, at: [<00000000587c8471>] >>> check_hung_uninterruptible_tasks kernel/hung_task.c:175 [inline] >>> #0: (rcu_read_lock){....}, at: [<00000000587c8471>] watchdog+0x1c5/0xd60 >>> kernel/hung_task.c:249 >>> #1: (tasklist_lock){.+.+}, at: [<000000005288685e>] >>> debug_show_all_locks+0xd3/0x400 kernel/locking/lockdep.c:4554 >>> 1 lock held by rsyslogd/2974: >>> #0: (&f->f_pos_lock){+.+.}, at: [<0000000011e00499>] >>> __fdget_pos+0x131/0x1a0 fs/file.c:770 >>> 2 locks held by getty/3056: >>> #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] >>> ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 >>> #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] >>> n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 >>> 2 locks held by getty/3057: >>> #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] >>> ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 >>> #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] >>> n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 >>> 2 locks held by getty/3058: >>> #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] >>> ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 >>> #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] >>> n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 >>> 2 locks held by getty/3059: >>> #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] >>> ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 >>> #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] >>> n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 >>> 2 locks held by getty/3060: >>> #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] >>> ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 >>> #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] >>> n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 >>> 2 locks held by getty/3061: >>> #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] >>> ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 >>> #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] >>> n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 >>> 2 locks held by getty/3062: >>> #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] >>> ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 >>> #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] >>> n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 >>> >>> ============================================= >>> >>> NMI backtrace for cpu 0 >>> CPU: 0 PID: 675 Comm: khungtaskd Not tainted 4.15.0-rc2-next-20171205+ #59 >>> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS >>> Google 01/01/2011 >>> Call Trace: >>> __dump_stack lib/dump_stack.c:17 [inline] >>> dump_stack+0x194/0x257 lib/dump_stack.c:53 >>> nmi_cpu_backtrace+0x1d2/0x210 lib/nmi_backtrace.c:103 >>> nmi_trigger_cpumask_backtrace+0x122/0x180 lib/nmi_backtrace.c:62 >>> arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 >>> trigger_all_cpu_backtrace include/linux/nmi.h:138 [inline] >>> check_hung_task kernel/hung_task.c:132 [inline] >>> check_hung_uninterruptible_tasks kernel/hung_task.c:190 [inline] >>> watchdog+0x90c/0xd60 kernel/hung_task.c:249 >>> kthread+0x37a/0x440 kernel/kthread.c:238 >>> ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:517 >>> Sending NMI from CPU 0 to CPUs 1: >>> NMI backtrace for cpu 1 >>> CPU: 1 PID: 13156 Comm: syz-executor7 Not tainted 4.15.0-rc2-next-20171205+ >>> #59 >>> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS >>> Google 01/01/2011 >>> task: 000000005209c120 task.stack: 00000000ffaab0e8 >>> RIP: 0010:inb arch/x86/include/asm/io.h:348 [inline] >>> RIP: 0010:io_serial_in+0x6b/0x90 drivers/tty/serial/8250/8250_port.c:434 >>> RSP: 0018:ffff8801c0a16e70 EFLAGS: 00000002 >>> RAX: dffffc0000000000 RBX: 00000000000003fd RCX: 0000000000000000 >>> RDX: 00000000000003fd RSI: ffffc90003745000 RDI: ffffffff87cf1a40 >>> RBP: ffff8801c0a16e80 R08: 0000000000000005 R09: 000000000000000c >>> R10: 0000000000000000 R11: ffffffff8748dd20 R12: ffffffff87cf1a00 >>> R13: 0000000000000020 R14: fffffbfff0f9e387 R15: fffffbfff0f9e34a >>> FS: 00007f6d52e3f700(0000) GS:ffff8801db500000(0000) knlGS:0000000000000000 >>> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 >>> CR2: 000000c42005de80 CR3: 00000001c368a000 CR4: 00000000001406e0 >>> DR0: 0000000020000000 DR1: 0000000000000000 DR2: 0000000000000000 >>> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 >>> Call Trace: >>> serial_in drivers/tty/serial/8250/8250.h:111 [inline] >>> wait_for_xmitr+0x93/0x1e0 drivers/tty/serial/8250/8250_port.c:2033 >>> serial8250_console_putchar+0x1f/0x60 >>> drivers/tty/serial/8250/8250_port.c:3170 >>> uart_console_write+0xac/0xe0 drivers/tty/serial/serial_core.c:1858 >>> serial8250_console_write+0x647/0xa20 >>> drivers/tty/serial/8250/8250_port.c:3236 >>> univ8250_console_write+0x5f/0x70 drivers/tty/serial/8250/8250_core.c:590 >>> call_console_drivers kernel/printk/printk.c:1574 [inline] >>> console_unlock+0x788/0xd70 kernel/printk/printk.c:2233 >>> vprintk_emit+0x4ad/0x590 kernel/printk/printk.c:1757 >>> vprintk_default+0x28/0x30 kernel/printk/printk.c:1796 >>> vprintk_func+0x57/0xc0 kernel/printk/printk_safe.c:379 >>> printk+0xaa/0xca kernel/printk/printk.c:1829 >>> nla_parse+0x374/0x3d0 lib/nlattr.c:257 >>> nlmsg_parse include/net/netlink.h:398 [inline] >>> nl80211_dump_wiphy_parse.isra.37.constprop.83+0x138/0x5c0 >>> net/wireless/nl80211.c:1920 >>> nl80211_dump_interface+0x596/0x820 net/wireless/nl80211.c:2660 >>> genl_lock_dumpit+0x68/0x90 net/netlink/genetlink.c:480 >>> netlink_dump+0x48c/0xce0 net/netlink/af_netlink.c:2186 >>> __netlink_dump_start+0x4f0/0x6d0 net/netlink/af_netlink.c:2283 >>> genl_family_rcv_msg+0xd27/0xfc0 net/netlink/genetlink.c:548 >>> genl_rcv_msg+0xb2/0x140 net/netlink/genetlink.c:624 >>> netlink_rcv_skb+0x216/0x440 net/netlink/af_netlink.c:2405 >>> genl_rcv+0x28/0x40 net/netlink/genetlink.c:635 >>> netlink_unicast_kernel net/netlink/af_netlink.c:1272 [inline] >>> netlink_unicast+0x4e8/0x6f0 net/netlink/af_netlink.c:1298 >>> netlink_sendmsg+0xa4a/0xe70 net/netlink/af_netlink.c:1861 >>> sock_sendmsg_nosec net/socket.c:636 [inline] >>> sock_sendmsg+0xca/0x110 net/socket.c:646 >>> sock_write_iter+0x320/0x5e0 net/socket.c:915 >>> call_write_iter include/linux/fs.h:1776 [inline] >>> new_sync_write fs/read_write.c:469 [inline] >>> __vfs_write+0x68a/0x970 fs/read_write.c:482 >>> vfs_write+0x18f/0x510 fs/read_write.c:544 >>> SYSC_write fs/read_write.c:589 [inline] >>> SyS_write+0xef/0x220 fs/read_write.c:581 >>> entry_SYSCALL_64_fastpath+0x1f/0x96 >>> RIP: 0033:0x4529d9 >>> RSP: 002b:00007f6d52e3ec58 EFLAGS: 00000212 ORIG_RAX: 0000000000000001 >>> RAX: ffffffffffffffda RBX: 00007f6d52e3f700 RCX: 00000000004529d9 >>> RDX: 0000000000000024 RSI: 0000000020454000 RDI: 0000000000000016 >>> RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 >>> R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000000 >>> R13: 0000000000a6f7ff R14: 00007f6d52e3f9c0 R15: 0000000000000000 >>> Code: 24 d9 00 00 00 49 8d 7c 24 40 48 b8 00 00 00 00 00 fc ff df 48 89 fa >>> 48 c1 ea 03 d3 e3 80 3c 02 00 75 17 41 03 5c 24 40 89 da ec <5b> 0f b6 c0 41 >>> 5c 5d c3 e8 38 b0 18 ff eb c2 e8 91 b0 18 ff eb >>> >>> >>> --- >>> This bug is generated by a dumb bot. It may contain errors. >>> See https://goo.gl/tpsmEJ for details. >>> Direct all questions to syzkaller@googlegroups.com. >>> Please credit me with: Reported-by: syzbot <syzkaller@googlegroups.com> >>> >>> syzbot will keep track of this bug report. >>> Once a fix for this bug is merged into any tree, reply to this email with: >>> #syz fix: exact-commit-title >>> To mark this as a duplicate of another syzbot report, please reply with: >>> #syz dup: exact-subject-of-another-report >>> If it's a one-off invalid bug report, please reply with: >>> #syz invalid >>> Note: if the crash happens again, it will cause creation of a new bug >>> report. >>> Note: all commands must start from beginning of the line in the email body. >>> >>> -- >>> You received this message because you are subscribed to the Google Groups >>> "syzkaller-bugs" group. >>> To unsubscribe from this group and stop receiving emails from it, send an >>> email to syzkaller-bugs+unsubscribe@googlegroups.com. >>> To view this discussion on the web visit >>> https://groups.google.com/d/msgid/syzkaller-bugs/001a1143fd00a8cc790560b0b552%40google.com. >>> For more options, visit https://groups.google.com/d/optout. >> >> >> This looks like +rtnetlink issue. >> > > Same with this one, perhaps related to / fixed by: > http://patchwork.ozlabs.org/patch/850957/ > Looking at the log, this one seems to be an infinite loop in SCTP code with console output in it. Kernel is busy printing gazilion of: [ 176.491099] sctp: sctp_transport_update_pmtu: Reported pmtu 508 too low, using default minimum of 512 ** 110 printk messages dropped ** [ 176.503409] sctp: sctp_transport_update_pmtu: Reported pmtu 508 too low, using default minimum of 512 ** 103 printk messages dropped ** ... [ 246.742374] sctp: sctp_transport_update_pmtu: Reported pmtu 508 too low, using default minimum of 512 [ 246.742484] sctp: sctp_transport_update_pmtu: Reported pmtu 508 too low, using default minimum of 512 [ 246.742590] sctp: sctp_transport_update_pmtu: Reported pmtu 508 too low, using default minimum of 512 Looks like a different issue. ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: INFO: task hung in bpf_exit_net 2017-12-22 10:58 ` Dmitry Vyukov @ 2017-12-22 11:16 ` Marcelo Ricardo Leitner 2017-12-22 11:24 ` Dmitry Vyukov 2017-12-22 18:28 ` Marcelo Ricardo Leitner 1 sibling, 1 reply; 9+ messages in thread From: Marcelo Ricardo Leitner @ 2017-12-22 11:16 UTC (permalink / raw) To: Dmitry Vyukov Cc: David Ahern, syzbot, LKML, Ingo Molnar, Peter Zijlstra, syzkaller-bugs, David Miller, Florian Westphal, Daniel Borkmann, Xin Long, jakub.kicinski, mschiffer, Vladislav Yasevich, Jiri Benc, netdev, Neil Horman, linux-sctp On Fri, Dec 22, 2017 at 11:58:08AM +0100, Dmitry Vyukov wrote: > On Tue, Dec 19, 2017 at 7:20 PM, David Ahern <dsahern@gmail.com> wrote: > > On 12/19/17 5:47 AM, Dmitry Vyukov wrote: > >> On Tue, Dec 19, 2017 at 1:36 PM, syzbot > >> <bot+21b498fc12cf2041655f8e1eeae0733807d794b3@syzkaller.appspotmail.com> > >> wrote: > >>> Hello, > >>> > >>> syzkaller hit the following crash on > >>> 7ceb97a071e80f1b5e4cd5a36de135612a836388 > >>> git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/master > >>> compiler: gcc (GCC) 7.1.1 20170620 > >>> .config is attached > >>> Raw console output is attached. > >>> > >>> Unfortunately, I don't have any reproducer for this bug yet. > >>> > >>> > >>> sctp: sctp_transport_update_pmtu: Reported pmtu 508 too low, using default > >>> minimum of 512 > >>> INFO: task kworker/u4:0:5 blocked for more than 120 seconds. > >>> Not tainted 4.15.0-rc2-next-20171205+ #59 > >>> "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. > >>> kworker/u4:0 D15808 5 2 0x80000000 > >>> Workqueue: netns cleanup_net > >>> Call Trace: > >>> context_switch kernel/sched/core.c:2800 [inline] > >>> __schedule+0x8eb/0x2060 kernel/sched/core.c:3376 > >>> schedule+0xf5/0x430 kernel/sched/core.c:3435 > >>> schedule_preempt_disabled+0x10/0x20 kernel/sched/core.c:3493 > >>> __mutex_lock_common kernel/locking/mutex.c:833 [inline] > >>> __mutex_lock+0xaad/0x1a80 kernel/locking/mutex.c:893 > >>> mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 > >>> rtnl_lock+0x17/0x20 net/core/rtnetlink.c:74 > >>> tc_action_net_exit include/net/act_api.h:125 [inline] > >>> bpf_exit_net+0x1a2/0x340 net/sched/act_bpf.c:408 > >>> ops_exit_list.isra.6+0xae/0x150 net/core/net_namespace.c:142 > >>> cleanup_net+0x5c7/0xb60 net/core/net_namespace.c:484 > >>> process_one_work+0xbfd/0x1bc0 kernel/workqueue.c:2113 > >>> worker_thread+0x223/0x1990 kernel/workqueue.c:2247 > >>> kthread+0x37a/0x440 kernel/kthread.c:238 > >>> ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:517 > >>> > >>> Showing all locks held in the system: > >>> 4 locks held by kworker/u4:0/5: > >>> #0: ((wq_completion)"%s""netns"){+.+.}, at: [<00000000b9f061a2>] > >>> __write_once_size include/linux/compiler.h:212 [inline] > >>> #0: ((wq_completion)"%s""netns"){+.+.}, at: [<00000000b9f061a2>] > >>> atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] > >>> #0: ((wq_completion)"%s""netns"){+.+.}, at: [<00000000b9f061a2>] > >>> atomic_long_set include/asm-generic/atomic-long.h:57 [inline] > >>> #0: ((wq_completion)"%s""netns"){+.+.}, at: [<00000000b9f061a2>] > >>> set_work_data kernel/workqueue.c:619 [inline] > >>> #0: ((wq_completion)"%s""netns"){+.+.}, at: [<00000000b9f061a2>] > >>> set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] > >>> #0: ((wq_completion)"%s""netns"){+.+.}, at: [<00000000b9f061a2>] > >>> process_one_work+0xad4/0x1bc0 kernel/workqueue.c:2084 > >>> #1: (net_cleanup_work){+.+.}, at: [<000000006c7c48a3>] > >>> process_one_work+0xb2f/0x1bc0 kernel/workqueue.c:2088 > >>> #2: (net_mutex){+.+.}, at: [<00000000bf4709f3>] cleanup_net+0x247/0xb60 > >>> net/core/net_namespace.c:450 > >>> #3: (rtnl_mutex){+.+.}, at: [<0000000053390f0b>] rtnl_lock+0x17/0x20 > >>> net/core/rtnetlink.c:74 > >>> 3 locks held by kworker/1:0/17: > >>> #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000b9f061a2>] > >>> __write_once_size include/linux/compiler.h:212 [inline] > >>> #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000b9f061a2>] > >>> atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] > >>> #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000b9f061a2>] > >>> atomic_long_set include/asm-generic/atomic-long.h:57 [inline] > >>> #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000b9f061a2>] > >>> set_work_data kernel/workqueue.c:619 [inline] > >>> #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000b9f061a2>] > >>> set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] > >>> #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000b9f061a2>] > >>> process_one_work+0xad4/0x1bc0 kernel/workqueue.c:2084 > >>> #1: ((addr_chk_work).work){+.+.}, at: [<000000006c7c48a3>] > >>> process_one_work+0xb2f/0x1bc0 kernel/workqueue.c:2088 > >>> #2: (rtnl_mutex){+.+.}, at: [<0000000053390f0b>] rtnl_lock+0x17/0x20 > >>> net/core/rtnetlink.c:74 > >>> 2 locks held by khungtaskd/675: > >>> #0: (rcu_read_lock){....}, at: [<00000000587c8471>] > >>> check_hung_uninterruptible_tasks kernel/hung_task.c:175 [inline] > >>> #0: (rcu_read_lock){....}, at: [<00000000587c8471>] watchdog+0x1c5/0xd60 > >>> kernel/hung_task.c:249 > >>> #1: (tasklist_lock){.+.+}, at: [<000000005288685e>] > >>> debug_show_all_locks+0xd3/0x400 kernel/locking/lockdep.c:4554 > >>> 1 lock held by rsyslogd/2974: > >>> #0: (&f->f_pos_lock){+.+.}, at: [<0000000011e00499>] > >>> __fdget_pos+0x131/0x1a0 fs/file.c:770 > >>> 2 locks held by getty/3056: > >>> #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] > >>> ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 > >>> #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] > >>> n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 > >>> 2 locks held by getty/3057: > >>> #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] > >>> ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 > >>> #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] > >>> n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 > >>> 2 locks held by getty/3058: > >>> #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] > >>> ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 > >>> #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] > >>> n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 > >>> 2 locks held by getty/3059: > >>> #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] > >>> ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 > >>> #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] > >>> n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 > >>> 2 locks held by getty/3060: > >>> #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] > >>> ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 > >>> #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] > >>> n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 > >>> 2 locks held by getty/3061: > >>> #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] > >>> ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 > >>> #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] > >>> n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 > >>> 2 locks held by getty/3062: > >>> #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] > >>> ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 > >>> #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] > >>> n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 > >>> > >>> ============================================= > >>> > >>> NMI backtrace for cpu 0 > >>> CPU: 0 PID: 675 Comm: khungtaskd Not tainted 4.15.0-rc2-next-20171205+ #59 > >>> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS > >>> Google 01/01/2011 > >>> Call Trace: > >>> __dump_stack lib/dump_stack.c:17 [inline] > >>> dump_stack+0x194/0x257 lib/dump_stack.c:53 > >>> nmi_cpu_backtrace+0x1d2/0x210 lib/nmi_backtrace.c:103 > >>> nmi_trigger_cpumask_backtrace+0x122/0x180 lib/nmi_backtrace.c:62 > >>> arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 > >>> trigger_all_cpu_backtrace include/linux/nmi.h:138 [inline] > >>> check_hung_task kernel/hung_task.c:132 [inline] > >>> check_hung_uninterruptible_tasks kernel/hung_task.c:190 [inline] > >>> watchdog+0x90c/0xd60 kernel/hung_task.c:249 > >>> kthread+0x37a/0x440 kernel/kthread.c:238 > >>> ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:517 > >>> Sending NMI from CPU 0 to CPUs 1: > >>> NMI backtrace for cpu 1 > >>> CPU: 1 PID: 13156 Comm: syz-executor7 Not tainted 4.15.0-rc2-next-20171205+ > >>> #59 > >>> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS > >>> Google 01/01/2011 > >>> task: 000000005209c120 task.stack: 00000000ffaab0e8 > >>> RIP: 0010:inb arch/x86/include/asm/io.h:348 [inline] > >>> RIP: 0010:io_serial_in+0x6b/0x90 drivers/tty/serial/8250/8250_port.c:434 > >>> RSP: 0018:ffff8801c0a16e70 EFLAGS: 00000002 > >>> RAX: dffffc0000000000 RBX: 00000000000003fd RCX: 0000000000000000 > >>> RDX: 00000000000003fd RSI: ffffc90003745000 RDI: ffffffff87cf1a40 > >>> RBP: ffff8801c0a16e80 R08: 0000000000000005 R09: 000000000000000c > >>> R10: 0000000000000000 R11: ffffffff8748dd20 R12: ffffffff87cf1a00 > >>> R13: 0000000000000020 R14: fffffbfff0f9e387 R15: fffffbfff0f9e34a > >>> FS: 00007f6d52e3f700(0000) GS:ffff8801db500000(0000) knlGS:0000000000000000 > >>> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > >>> CR2: 000000c42005de80 CR3: 00000001c368a000 CR4: 00000000001406e0 > >>> DR0: 0000000020000000 DR1: 0000000000000000 DR2: 0000000000000000 > >>> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 > >>> Call Trace: > >>> serial_in drivers/tty/serial/8250/8250.h:111 [inline] > >>> wait_for_xmitr+0x93/0x1e0 drivers/tty/serial/8250/8250_port.c:2033 > >>> serial8250_console_putchar+0x1f/0x60 > >>> drivers/tty/serial/8250/8250_port.c:3170 > >>> uart_console_write+0xac/0xe0 drivers/tty/serial/serial_core.c:1858 > >>> serial8250_console_write+0x647/0xa20 > >>> drivers/tty/serial/8250/8250_port.c:3236 > >>> univ8250_console_write+0x5f/0x70 drivers/tty/serial/8250/8250_core.c:590 > >>> call_console_drivers kernel/printk/printk.c:1574 [inline] > >>> console_unlock+0x788/0xd70 kernel/printk/printk.c:2233 > >>> vprintk_emit+0x4ad/0x590 kernel/printk/printk.c:1757 > >>> vprintk_default+0x28/0x30 kernel/printk/printk.c:1796 > >>> vprintk_func+0x57/0xc0 kernel/printk/printk_safe.c:379 > >>> printk+0xaa/0xca kernel/printk/printk.c:1829 > >>> nla_parse+0x374/0x3d0 lib/nlattr.c:257 > >>> nlmsg_parse include/net/netlink.h:398 [inline] > >>> nl80211_dump_wiphy_parse.isra.37.constprop.83+0x138/0x5c0 > >>> net/wireless/nl80211.c:1920 > >>> nl80211_dump_interface+0x596/0x820 net/wireless/nl80211.c:2660 > >>> genl_lock_dumpit+0x68/0x90 net/netlink/genetlink.c:480 > >>> netlink_dump+0x48c/0xce0 net/netlink/af_netlink.c:2186 > >>> __netlink_dump_start+0x4f0/0x6d0 net/netlink/af_netlink.c:2283 > >>> genl_family_rcv_msg+0xd27/0xfc0 net/netlink/genetlink.c:548 > >>> genl_rcv_msg+0xb2/0x140 net/netlink/genetlink.c:624 > >>> netlink_rcv_skb+0x216/0x440 net/netlink/af_netlink.c:2405 > >>> genl_rcv+0x28/0x40 net/netlink/genetlink.c:635 > >>> netlink_unicast_kernel net/netlink/af_netlink.c:1272 [inline] > >>> netlink_unicast+0x4e8/0x6f0 net/netlink/af_netlink.c:1298 > >>> netlink_sendmsg+0xa4a/0xe70 net/netlink/af_netlink.c:1861 > >>> sock_sendmsg_nosec net/socket.c:636 [inline] > >>> sock_sendmsg+0xca/0x110 net/socket.c:646 > >>> sock_write_iter+0x320/0x5e0 net/socket.c:915 > >>> call_write_iter include/linux/fs.h:1776 [inline] > >>> new_sync_write fs/read_write.c:469 [inline] > >>> __vfs_write+0x68a/0x970 fs/read_write.c:482 > >>> vfs_write+0x18f/0x510 fs/read_write.c:544 > >>> SYSC_write fs/read_write.c:589 [inline] > >>> SyS_write+0xef/0x220 fs/read_write.c:581 > >>> entry_SYSCALL_64_fastpath+0x1f/0x96 > >>> RIP: 0033:0x4529d9 > >>> RSP: 002b:00007f6d52e3ec58 EFLAGS: 00000212 ORIG_RAX: 0000000000000001 > >>> RAX: ffffffffffffffda RBX: 00007f6d52e3f700 RCX: 00000000004529d9 > >>> RDX: 0000000000000024 RSI: 0000000020454000 RDI: 0000000000000016 > >>> RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 > >>> R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000000 > >>> R13: 0000000000a6f7ff R14: 00007f6d52e3f9c0 R15: 0000000000000000 > >>> Code: 24 d9 00 00 00 49 8d 7c 24 40 48 b8 00 00 00 00 00 fc ff df 48 89 fa > >>> 48 c1 ea 03 d3 e3 80 3c 02 00 75 17 41 03 5c 24 40 89 da ec <5b> 0f b6 c0 41 > >>> 5c 5d c3 e8 38 b0 18 ff eb c2 e8 91 b0 18 ff eb > >>> > >>> > >>> --- > >>> This bug is generated by a dumb bot. It may contain errors. > >>> See https://goo.gl/tpsmEJ for details. > >>> Direct all questions to syzkaller@googlegroups.com. > >>> Please credit me with: Reported-by: syzbot <syzkaller@googlegroups.com> > >>> > >>> syzbot will keep track of this bug report. > >>> Once a fix for this bug is merged into any tree, reply to this email with: > >>> #syz fix: exact-commit-title > >>> To mark this as a duplicate of another syzbot report, please reply with: > >>> #syz dup: exact-subject-of-another-report > >>> If it's a one-off invalid bug report, please reply with: > >>> #syz invalid > >>> Note: if the crash happens again, it will cause creation of a new bug > >>> report. > >>> Note: all commands must start from beginning of the line in the email body. > >>> > >>> -- > >>> You received this message because you are subscribed to the Google Groups > >>> "syzkaller-bugs" group. > >>> To unsubscribe from this group and stop receiving emails from it, send an > >>> email to syzkaller-bugs+unsubscribe@googlegroups.com. > >>> To view this discussion on the web visit > >>> https://groups.google.com/d/msgid/syzkaller-bugs/001a1143fd00a8cc790560b0b552%40google.com. > >>> For more options, visit https://groups.google.com/d/optout. > >> > >> > >> This looks like +rtnetlink issue. > >> > > > > Same with this one, perhaps related to / fixed by: > > http://patchwork.ozlabs.org/patch/850957/ > > > > > > Looking at the log, this one seems to be an infinite loop in SCTP code > with console output in it. Kernel is busy printing gazilion of: Do you have a link for such log? I don't seem to have received the initial syzbot email, so I don't have its attachments. Or if you may, please fwd it to me/list. Thanks. > > [ 176.491099] sctp: sctp_transport_update_pmtu: Reported pmtu 508 too > low, using default minimum of 512 > ** 110 printk messages dropped ** > [ 176.503409] sctp: sctp_transport_update_pmtu: Reported pmtu 508 too > low, using default minimum of 512 > ** 103 printk messages dropped ** > ... > [ 246.742374] sctp: sctp_transport_update_pmtu: Reported pmtu 508 too > low, using default minimum of 512 > [ 246.742484] sctp: sctp_transport_update_pmtu: Reported pmtu 508 too > low, using default minimum of 512 > [ 246.742590] sctp: sctp_transport_update_pmtu: Reported pmtu 508 too > low, using default minimum of 512 > > Looks like a different issue. > ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: INFO: task hung in bpf_exit_net 2017-12-22 11:16 ` Marcelo Ricardo Leitner @ 2017-12-22 11:24 ` Dmitry Vyukov 0 siblings, 0 replies; 9+ messages in thread From: Dmitry Vyukov @ 2017-12-22 11:24 UTC (permalink / raw) To: Marcelo Ricardo Leitner Cc: David Ahern, syzbot, LKML, Ingo Molnar, Peter Zijlstra, syzkaller-bugs, David Miller, Florian Westphal, Daniel Borkmann, Xin Long, jakub.kicinski, mschiffer, Vladislav Yasevich, Jiri Benc, netdev, Neil Horman, linux-sctp On Fri, Dec 22, 2017 at 12:16 PM, Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> wrote: > On Fri, Dec 22, 2017 at 11:58:08AM +0100, Dmitry Vyukov wrote: >> On Tue, Dec 19, 2017 at 7:20 PM, David Ahern <dsahern@gmail.com> wrote: >> > On 12/19/17 5:47 AM, Dmitry Vyukov wrote: >> >> On Tue, Dec 19, 2017 at 1:36 PM, syzbot >> >> <bot+21b498fc12cf2041655f8e1eeae0733807d794b3@syzkaller.appspotmail.com> >> >> wrote: >> >>> Hello, >> >>> >> >>> syzkaller hit the following crash on >> >>> 7ceb97a071e80f1b5e4cd5a36de135612a836388 >> >>> git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/master >> >>> compiler: gcc (GCC) 7.1.1 20170620 >> >>> .config is attached >> >>> Raw console output is attached. >> >>> >> >>> Unfortunately, I don't have any reproducer for this bug yet. >> >>> >> >>> >> >>> sctp: sctp_transport_update_pmtu: Reported pmtu 508 too low, using default >> >>> minimum of 512 >> >>> INFO: task kworker/u4:0:5 blocked for more than 120 seconds. >> >>> Not tainted 4.15.0-rc2-next-20171205+ #59 >> >>> "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. >> >>> kworker/u4:0 D15808 5 2 0x80000000 >> >>> Workqueue: netns cleanup_net >> >>> Call Trace: >> >>> context_switch kernel/sched/core.c:2800 [inline] >> >>> __schedule+0x8eb/0x2060 kernel/sched/core.c:3376 >> >>> schedule+0xf5/0x430 kernel/sched/core.c:3435 >> >>> schedule_preempt_disabled+0x10/0x20 kernel/sched/core.c:3493 >> >>> __mutex_lock_common kernel/locking/mutex.c:833 [inline] >> >>> __mutex_lock+0xaad/0x1a80 kernel/locking/mutex.c:893 >> >>> mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 >> >>> rtnl_lock+0x17/0x20 net/core/rtnetlink.c:74 >> >>> tc_action_net_exit include/net/act_api.h:125 [inline] >> >>> bpf_exit_net+0x1a2/0x340 net/sched/act_bpf.c:408 >> >>> ops_exit_list.isra.6+0xae/0x150 net/core/net_namespace.c:142 >> >>> cleanup_net+0x5c7/0xb60 net/core/net_namespace.c:484 >> >>> process_one_work+0xbfd/0x1bc0 kernel/workqueue.c:2113 >> >>> worker_thread+0x223/0x1990 kernel/workqueue.c:2247 >> >>> kthread+0x37a/0x440 kernel/kthread.c:238 >> >>> ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:517 >> >>> >> >>> Showing all locks held in the system: >> >>> 4 locks held by kworker/u4:0/5: >> >>> #0: ((wq_completion)"%s""netns"){+.+.}, at: [<00000000b9f061a2>] >> >>> __write_once_size include/linux/compiler.h:212 [inline] >> >>> #0: ((wq_completion)"%s""netns"){+.+.}, at: [<00000000b9f061a2>] >> >>> atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] >> >>> #0: ((wq_completion)"%s""netns"){+.+.}, at: [<00000000b9f061a2>] >> >>> atomic_long_set include/asm-generic/atomic-long.h:57 [inline] >> >>> #0: ((wq_completion)"%s""netns"){+.+.}, at: [<00000000b9f061a2>] >> >>> set_work_data kernel/workqueue.c:619 [inline] >> >>> #0: ((wq_completion)"%s""netns"){+.+.}, at: [<00000000b9f061a2>] >> >>> set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] >> >>> #0: ((wq_completion)"%s""netns"){+.+.}, at: [<00000000b9f061a2>] >> >>> process_one_work+0xad4/0x1bc0 kernel/workqueue.c:2084 >> >>> #1: (net_cleanup_work){+.+.}, at: [<000000006c7c48a3>] >> >>> process_one_work+0xb2f/0x1bc0 kernel/workqueue.c:2088 >> >>> #2: (net_mutex){+.+.}, at: [<00000000bf4709f3>] cleanup_net+0x247/0xb60 >> >>> net/core/net_namespace.c:450 >> >>> #3: (rtnl_mutex){+.+.}, at: [<0000000053390f0b>] rtnl_lock+0x17/0x20 >> >>> net/core/rtnetlink.c:74 >> >>> 3 locks held by kworker/1:0/17: >> >>> #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000b9f061a2>] >> >>> __write_once_size include/linux/compiler.h:212 [inline] >> >>> #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000b9f061a2>] >> >>> atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] >> >>> #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000b9f061a2>] >> >>> atomic_long_set include/asm-generic/atomic-long.h:57 [inline] >> >>> #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000b9f061a2>] >> >>> set_work_data kernel/workqueue.c:619 [inline] >> >>> #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000b9f061a2>] >> >>> set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] >> >>> #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000b9f061a2>] >> >>> process_one_work+0xad4/0x1bc0 kernel/workqueue.c:2084 >> >>> #1: ((addr_chk_work).work){+.+.}, at: [<000000006c7c48a3>] >> >>> process_one_work+0xb2f/0x1bc0 kernel/workqueue.c:2088 >> >>> #2: (rtnl_mutex){+.+.}, at: [<0000000053390f0b>] rtnl_lock+0x17/0x20 >> >>> net/core/rtnetlink.c:74 >> >>> 2 locks held by khungtaskd/675: >> >>> #0: (rcu_read_lock){....}, at: [<00000000587c8471>] >> >>> check_hung_uninterruptible_tasks kernel/hung_task.c:175 [inline] >> >>> #0: (rcu_read_lock){....}, at: [<00000000587c8471>] watchdog+0x1c5/0xd60 >> >>> kernel/hung_task.c:249 >> >>> #1: (tasklist_lock){.+.+}, at: [<000000005288685e>] >> >>> debug_show_all_locks+0xd3/0x400 kernel/locking/lockdep.c:4554 >> >>> 1 lock held by rsyslogd/2974: >> >>> #0: (&f->f_pos_lock){+.+.}, at: [<0000000011e00499>] >> >>> __fdget_pos+0x131/0x1a0 fs/file.c:770 >> >>> 2 locks held by getty/3056: >> >>> #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] >> >>> ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 >> >>> #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] >> >>> n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 >> >>> 2 locks held by getty/3057: >> >>> #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] >> >>> ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 >> >>> #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] >> >>> n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 >> >>> 2 locks held by getty/3058: >> >>> #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] >> >>> ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 >> >>> #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] >> >>> n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 >> >>> 2 locks held by getty/3059: >> >>> #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] >> >>> ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 >> >>> #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] >> >>> n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 >> >>> 2 locks held by getty/3060: >> >>> #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] >> >>> ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 >> >>> #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] >> >>> n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 >> >>> 2 locks held by getty/3061: >> >>> #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] >> >>> ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 >> >>> #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] >> >>> n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 >> >>> 2 locks held by getty/3062: >> >>> #0: (&tty->ldisc_sem){++++}, at: [<00000000b9fd70a9>] >> >>> ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 >> >>> #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000abb3bd08>] >> >>> n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131 >> >>> >> >>> ============================================= >> >>> >> >>> NMI backtrace for cpu 0 >> >>> CPU: 0 PID: 675 Comm: khungtaskd Not tainted 4.15.0-rc2-next-20171205+ #59 >> >>> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS >> >>> Google 01/01/2011 >> >>> Call Trace: >> >>> __dump_stack lib/dump_stack.c:17 [inline] >> >>> dump_stack+0x194/0x257 lib/dump_stack.c:53 >> >>> nmi_cpu_backtrace+0x1d2/0x210 lib/nmi_backtrace.c:103 >> >>> nmi_trigger_cpumask_backtrace+0x122/0x180 lib/nmi_backtrace.c:62 >> >>> arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 >> >>> trigger_all_cpu_backtrace include/linux/nmi.h:138 [inline] >> >>> check_hung_task kernel/hung_task.c:132 [inline] >> >>> check_hung_uninterruptible_tasks kernel/hung_task.c:190 [inline] >> >>> watchdog+0x90c/0xd60 kernel/hung_task.c:249 >> >>> kthread+0x37a/0x440 kernel/kthread.c:238 >> >>> ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:517 >> >>> Sending NMI from CPU 0 to CPUs 1: >> >>> NMI backtrace for cpu 1 >> >>> CPU: 1 PID: 13156 Comm: syz-executor7 Not tainted 4.15.0-rc2-next-20171205+ >> >>> #59 >> >>> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS >> >>> Google 01/01/2011 >> >>> task: 000000005209c120 task.stack: 00000000ffaab0e8 >> >>> RIP: 0010:inb arch/x86/include/asm/io.h:348 [inline] >> >>> RIP: 0010:io_serial_in+0x6b/0x90 drivers/tty/serial/8250/8250_port.c:434 >> >>> RSP: 0018:ffff8801c0a16e70 EFLAGS: 00000002 >> >>> RAX: dffffc0000000000 RBX: 00000000000003fd RCX: 0000000000000000 >> >>> RDX: 00000000000003fd RSI: ffffc90003745000 RDI: ffffffff87cf1a40 >> >>> RBP: ffff8801c0a16e80 R08: 0000000000000005 R09: 000000000000000c >> >>> R10: 0000000000000000 R11: ffffffff8748dd20 R12: ffffffff87cf1a00 >> >>> R13: 0000000000000020 R14: fffffbfff0f9e387 R15: fffffbfff0f9e34a >> >>> FS: 00007f6d52e3f700(0000) GS:ffff8801db500000(0000) knlGS:0000000000000000 >> >>> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 >> >>> CR2: 000000c42005de80 CR3: 00000001c368a000 CR4: 00000000001406e0 >> >>> DR0: 0000000020000000 DR1: 0000000000000000 DR2: 0000000000000000 >> >>> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 >> >>> Call Trace: >> >>> serial_in drivers/tty/serial/8250/8250.h:111 [inline] >> >>> wait_for_xmitr+0x93/0x1e0 drivers/tty/serial/8250/8250_port.c:2033 >> >>> serial8250_console_putchar+0x1f/0x60 >> >>> drivers/tty/serial/8250/8250_port.c:3170 >> >>> uart_console_write+0xac/0xe0 drivers/tty/serial/serial_core.c:1858 >> >>> serial8250_console_write+0x647/0xa20 >> >>> drivers/tty/serial/8250/8250_port.c:3236 >> >>> univ8250_console_write+0x5f/0x70 drivers/tty/serial/8250/8250_core.c:590 >> >>> call_console_drivers kernel/printk/printk.c:1574 [inline] >> >>> console_unlock+0x788/0xd70 kernel/printk/printk.c:2233 >> >>> vprintk_emit+0x4ad/0x590 kernel/printk/printk.c:1757 >> >>> vprintk_default+0x28/0x30 kernel/printk/printk.c:1796 >> >>> vprintk_func+0x57/0xc0 kernel/printk/printk_safe.c:379 >> >>> printk+0xaa/0xca kernel/printk/printk.c:1829 >> >>> nla_parse+0x374/0x3d0 lib/nlattr.c:257 >> >>> nlmsg_parse include/net/netlink.h:398 [inline] >> >>> nl80211_dump_wiphy_parse.isra.37.constprop.83+0x138/0x5c0 >> >>> net/wireless/nl80211.c:1920 >> >>> nl80211_dump_interface+0x596/0x820 net/wireless/nl80211.c:2660 >> >>> genl_lock_dumpit+0x68/0x90 net/netlink/genetlink.c:480 >> >>> netlink_dump+0x48c/0xce0 net/netlink/af_netlink.c:2186 >> >>> __netlink_dump_start+0x4f0/0x6d0 net/netlink/af_netlink.c:2283 >> >>> genl_family_rcv_msg+0xd27/0xfc0 net/netlink/genetlink.c:548 >> >>> genl_rcv_msg+0xb2/0x140 net/netlink/genetlink.c:624 >> >>> netlink_rcv_skb+0x216/0x440 net/netlink/af_netlink.c:2405 >> >>> genl_rcv+0x28/0x40 net/netlink/genetlink.c:635 >> >>> netlink_unicast_kernel net/netlink/af_netlink.c:1272 [inline] >> >>> netlink_unicast+0x4e8/0x6f0 net/netlink/af_netlink.c:1298 >> >>> netlink_sendmsg+0xa4a/0xe70 net/netlink/af_netlink.c:1861 >> >>> sock_sendmsg_nosec net/socket.c:636 [inline] >> >>> sock_sendmsg+0xca/0x110 net/socket.c:646 >> >>> sock_write_iter+0x320/0x5e0 net/socket.c:915 >> >>> call_write_iter include/linux/fs.h:1776 [inline] >> >>> new_sync_write fs/read_write.c:469 [inline] >> >>> __vfs_write+0x68a/0x970 fs/read_write.c:482 >> >>> vfs_write+0x18f/0x510 fs/read_write.c:544 >> >>> SYSC_write fs/read_write.c:589 [inline] >> >>> SyS_write+0xef/0x220 fs/read_write.c:581 >> >>> entry_SYSCALL_64_fastpath+0x1f/0x96 >> >>> RIP: 0033:0x4529d9 >> >>> RSP: 002b:00007f6d52e3ec58 EFLAGS: 00000212 ORIG_RAX: 0000000000000001 >> >>> RAX: ffffffffffffffda RBX: 00007f6d52e3f700 RCX: 00000000004529d9 >> >>> RDX: 0000000000000024 RSI: 0000000020454000 RDI: 0000000000000016 >> >>> RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 >> >>> R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000000 >> >>> R13: 0000000000a6f7ff R14: 00007f6d52e3f9c0 R15: 0000000000000000 >> >>> Code: 24 d9 00 00 00 49 8d 7c 24 40 48 b8 00 00 00 00 00 fc ff df 48 89 fa >> >>> 48 c1 ea 03 d3 e3 80 3c 02 00 75 17 41 03 5c 24 40 89 da ec <5b> 0f b6 c0 41 >> >>> 5c 5d c3 e8 38 b0 18 ff eb c2 e8 91 b0 18 ff eb >> >>> >> >>> >> >>> --- >> >>> This bug is generated by a dumb bot. It may contain errors. >> >>> See https://goo.gl/tpsmEJ for details. >> >>> Direct all questions to syzkaller@googlegroups.com. >> >>> Please credit me with: Reported-by: syzbot <syzkaller@googlegroups.com> >> >>> >> >>> syzbot will keep track of this bug report. >> >>> Once a fix for this bug is merged into any tree, reply to this email with: >> >>> #syz fix: exact-commit-title >> >>> To mark this as a duplicate of another syzbot report, please reply with: >> >>> #syz dup: exact-subject-of-another-report >> >>> If it's a one-off invalid bug report, please reply with: >> >>> #syz invalid >> >>> Note: if the crash happens again, it will cause creation of a new bug >> >>> report. >> >>> Note: all commands must start from beginning of the line in the email body. >> >>> >> >>> -- >> >>> You received this message because you are subscribed to the Google Groups >> >>> "syzkaller-bugs" group. >> >>> To unsubscribe from this group and stop receiving emails from it, send an >> >>> email to syzkaller-bugs+unsubscribe@googlegroups.com. >> >>> To view this discussion on the web visit >> >>> https://groups.google.com/d/msgid/syzkaller-bugs/001a1143fd00a8cc790560b0b552%40google.com. >> >>> For more options, visit https://groups.google.com/d/optout. >> >> >> >> >> >> This looks like +rtnetlink issue. >> >> >> > >> > Same with this one, perhaps related to / fixed by: >> > http://patchwork.ozlabs.org/patch/850957/ >> > >> >> >> >> Looking at the log, this one seems to be an infinite loop in SCTP code >> with console output in it. Kernel is busy printing gazilion of: > > Do you have a link for such log? I don't seem to have received the > initial syzbot email, so I don't have its attachments. Or if you may, > please fwd it to me/list. https://groups.google.com/forum/#!searchin/syzkaller-bugs/%22INFO$3A$20task$20hung$20in$20bpf_exit_net%22%7Csort:date > Thanks. > >> >> [ 176.491099] sctp: sctp_transport_update_pmtu: Reported pmtu 508 too >> low, using default minimum of 512 >> ** 110 printk messages dropped ** >> [ 176.503409] sctp: sctp_transport_update_pmtu: Reported pmtu 508 too >> low, using default minimum of 512 >> ** 103 printk messages dropped ** >> ... >> [ 246.742374] sctp: sctp_transport_update_pmtu: Reported pmtu 508 too >> low, using default minimum of 512 >> [ 246.742484] sctp: sctp_transport_update_pmtu: Reported pmtu 508 too >> low, using default minimum of 512 >> [ 246.742590] sctp: sctp_transport_update_pmtu: Reported pmtu 508 too >> low, using default minimum of 512 >> >> Looks like a different issue. >> ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: INFO: task hung in bpf_exit_net 2017-12-22 10:58 ` Dmitry Vyukov 2017-12-22 11:16 ` Marcelo Ricardo Leitner @ 2017-12-22 18:28 ` Marcelo Ricardo Leitner 2017-12-22 19:04 ` Marcelo Ricardo Leitner 1 sibling, 1 reply; 9+ messages in thread From: Marcelo Ricardo Leitner @ 2017-12-22 18:28 UTC (permalink / raw) To: Dmitry Vyukov Cc: David Ahern, syzbot, LKML, Ingo Molnar, Peter Zijlstra, syzkaller-bugs, David Miller, Florian Westphal, Daniel Borkmann, Xin Long, jakub.kicinski, mschiffer, Vladislav Yasevich, Jiri Benc, netdev, Neil Horman, linux-sctp On Fri, Dec 22, 2017 at 11:58:08AM +0100, Dmitry Vyukov wrote: ... > > Same with this one, perhaps related to / fixed by: > > http://patchwork.ozlabs.org/patch/850957/ > > > > > > Looking at the log, this one seems to be an infinite loop in SCTP code > with console output in it. Kernel is busy printing gazilion of: > > [ 176.491099] sctp: sctp_transport_update_pmtu: Reported pmtu 508 too > low, using default minimum of 512 > ** 110 printk messages dropped ** > [ 176.503409] sctp: sctp_transport_update_pmtu: Reported pmtu 508 too > low, using default minimum of 512 > ** 103 printk messages dropped ** > ... > [ 246.742374] sctp: sctp_transport_update_pmtu: Reported pmtu 508 too > low, using default minimum of 512 > [ 246.742484] sctp: sctp_transport_update_pmtu: Reported pmtu 508 too > low, using default minimum of 512 > [ 246.742590] sctp: sctp_transport_update_pmtu: Reported pmtu 508 too > low, using default minimum of 512 > > Looks like a different issue. > Oh. I guess this is caused by the interface having a MTU smaller than SCTP_DEFAULT_MINSEGMENT (512), as the icmp frag needed handler (sctp_icmp_frag_needed) will trigger an instant retransmission. But as the MTU is smaller, SCTP won't update it, but will issue the retransmission anyway. I will test this soon. Should be fairly easy to trigger it. Marcelo ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: INFO: task hung in bpf_exit_net 2017-12-22 18:28 ` Marcelo Ricardo Leitner @ 2017-12-22 19:04 ` Marcelo Ricardo Leitner 2018-02-02 23:39 ` Eric Biggers 0 siblings, 1 reply; 9+ messages in thread From: Marcelo Ricardo Leitner @ 2017-12-22 19:04 UTC (permalink / raw) To: Dmitry Vyukov Cc: David Ahern, syzbot, LKML, Ingo Molnar, Peter Zijlstra, syzkaller-bugs, David Miller, Florian Westphal, Daniel Borkmann, Xin Long, jakub.kicinski, mschiffer, Vladislav Yasevich, Jiri Benc, netdev, Neil Horman, linux-sctp On Fri, Dec 22, 2017 at 04:28:07PM -0200, Marcelo Ricardo Leitner wrote: > On Fri, Dec 22, 2017 at 11:58:08AM +0100, Dmitry Vyukov wrote: > ... > > > Same with this one, perhaps related to / fixed by: > > > http://patchwork.ozlabs.org/patch/850957/ > > > > > > > > > > > Looking at the log, this one seems to be an infinite loop in SCTP code > > with console output in it. Kernel is busy printing gazilion of: > > > > [ 176.491099] sctp: sctp_transport_update_pmtu: Reported pmtu 508 too > > low, using default minimum of 512 > > ** 110 printk messages dropped ** > > [ 176.503409] sctp: sctp_transport_update_pmtu: Reported pmtu 508 too > > low, using default minimum of 512 > > ** 103 printk messages dropped ** > > ... > > [ 246.742374] sctp: sctp_transport_update_pmtu: Reported pmtu 508 too > > low, using default minimum of 512 > > [ 246.742484] sctp: sctp_transport_update_pmtu: Reported pmtu 508 too > > low, using default minimum of 512 > > [ 246.742590] sctp: sctp_transport_update_pmtu: Reported pmtu 508 too > > low, using default minimum of 512 > > > > Looks like a different issue. > > > > Oh. I guess this is caused by the interface having a MTU smaller than > SCTP_DEFAULT_MINSEGMENT (512), as the icmp frag needed handler > (sctp_icmp_frag_needed) will trigger an instant retransmission. > But as the MTU is smaller, SCTP won't update it, but will issue the > retransmission anyway. > > I will test this soon. Should be fairly easy to trigger it. Reproduced it. netns A veth0(1500) - veth1(1500) B veth2(508) - veth3(508) C When A sends a sctp packet bigger than 508, it triggers the issue as B will reply a icmp frag needed with a size that sctp won't accept but will retransmit anyway. Marcelo ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: INFO: task hung in bpf_exit_net 2017-12-22 19:04 ` Marcelo Ricardo Leitner @ 2018-02-02 23:39 ` Eric Biggers 0 siblings, 0 replies; 9+ messages in thread From: Eric Biggers @ 2018-02-02 23:39 UTC (permalink / raw) To: Marcelo Ricardo Leitner Cc: Dmitry Vyukov, David Ahern, syzbot, LKML, Ingo Molnar, Peter Zijlstra, syzkaller-bugs, David Miller, Florian Westphal, Daniel Borkmann, Xin Long, jakub.kicinski, mschiffer, Vladislav Yasevich, Jiri Benc, netdev, Neil Horman, linux-sctp On Fri, Dec 22, 2017 at 05:04:37PM -0200, Marcelo Ricardo Leitner wrote: > On Fri, Dec 22, 2017 at 04:28:07PM -0200, Marcelo Ricardo Leitner wrote: > > On Fri, Dec 22, 2017 at 11:58:08AM +0100, Dmitry Vyukov wrote: > > ... > > > > Same with this one, perhaps related to / fixed by: > > > > http://patchwork.ozlabs.org/patch/850957/ > > > > > > > > > > > > > > > > Looking at the log, this one seems to be an infinite loop in SCTP code > > > with console output in it. Kernel is busy printing gazilion of: > > > > > > [ 176.491099] sctp: sctp_transport_update_pmtu: Reported pmtu 508 too > > > low, using default minimum of 512 > > > ** 110 printk messages dropped ** > > > [ 176.503409] sctp: sctp_transport_update_pmtu: Reported pmtu 508 too > > > low, using default minimum of 512 > > > ** 103 printk messages dropped ** > > > ... > > > [ 246.742374] sctp: sctp_transport_update_pmtu: Reported pmtu 508 too > > > low, using default minimum of 512 > > > [ 246.742484] sctp: sctp_transport_update_pmtu: Reported pmtu 508 too > > > low, using default minimum of 512 > > > [ 246.742590] sctp: sctp_transport_update_pmtu: Reported pmtu 508 too > > > low, using default minimum of 512 > > > > > > Looks like a different issue. > > > > > > > Oh. I guess this is caused by the interface having a MTU smaller than > > SCTP_DEFAULT_MINSEGMENT (512), as the icmp frag needed handler > > (sctp_icmp_frag_needed) will trigger an instant retransmission. > > But as the MTU is smaller, SCTP won't update it, but will issue the > > retransmission anyway. > > > > I will test this soon. Should be fairly easy to trigger it. > > Reproduced it. > > netns A veth0(1500) - veth1(1500) B veth2(508) - veth3(508) C > > When A sends a sctp packet bigger than 508, it triggers the issue as B > will reply a icmp frag needed with a size that sctp won't accept but > will retransmit anyway. > syzbot hasn't encountered this hang again (although, it just happened once in the first place). I assume it was fixed by commit b6c5734db070, so telling syzbot this: #syz fix: sctp: fix the handling of ICMP Frag Needed for too small MTUs - Eric ^ permalink raw reply [flat|nested] 9+ messages in thread
end of thread, other threads:[~2018-02-02 23:40 UTC | newest]
Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed)
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2017-12-19 12:47 ` INFO: task hung in bpf_exit_net Dmitry Vyukov
2017-12-19 16:21 ` Xin Long
2017-12-19 18:20 ` David Ahern
2017-12-22 10:58 ` Dmitry Vyukov
2017-12-22 11:16 ` Marcelo Ricardo Leitner
2017-12-22 11:24 ` Dmitry Vyukov
2017-12-22 18:28 ` Marcelo Ricardo Leitner
2017-12-22 19:04 ` Marcelo Ricardo Leitner
2018-02-02 23:39 ` Eric Biggers
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