On Mon, Mar 19, 2018 at 9:31 AM, syzbot <syzbot+a13db9a2536a9c41c...@syzkaller.appspotmail.com> wrote: > Hello, > > syzbot hit the following crash on upstream commit > 8f5fd927c3a7576d57248a2d7a0861c3f2795973 (Fri Mar 16 20:37:42 2018 +0000) > Merge tag 'for-4.16-rc5-tag' of > git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux > > Unfortunately, I don't have any reproducer for this crash yet. > Raw console output is attached. > compiler: gcc (GCC) 7.1.1 20170620 > .config is attached.
Another hung task on rtnl_lock: #syz dup: INFO: task hung in netdev_run_todo > IMPORTANT: if you fix the bug, please add the following tag to the commit: > Reported-by: syzbot+a13db9a2536a9c41c...@syzkaller.appspotmail.com > It will help syzbot understand when the bug is fixed. See footer for > details. > If you forward the report, please keep this part and the footer. > > INFO: task syz-executor1:22250 blocked for more than 120 seconds. > Not tainted 4.16.0-rc5+ #357 > "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. > syz-executor1 D25184 22250 4289 0x00000004 > Call Trace: > context_switch kernel/sched/core.c:2862 [inline] > __schedule+0x8fb/0x1ec0 kernel/sched/core.c:3440 > schedule+0xf5/0x430 kernel/sched/core.c:3499 > schedule_preempt_disabled+0x10/0x20 kernel/sched/core.c:3557 > __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 > __tun_chr_ioctl+0x1b1/0x40d0 drivers/net/tun.c:2810 > tun_chr_ioctl+0x2a/0x40 drivers/net/tun.c:3077 > vfs_ioctl fs/ioctl.c:46 [inline] > do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:686 > SYSC_ioctl fs/ioctl.c:701 [inline] > SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692 > do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287 > entry_SYSCALL_64_after_hwframe+0x42/0xb7 > RIP: 0033:0x453e69 > RSP: 002b:00007fa8a093bc68 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 > RAX: ffffffffffffffda RBX: 00007fa8a093c6d4 RCX: 0000000000453e69 > RDX: 0000000020000080 RSI: 00000000400454ca RDI: 0000000000000013 > RBP: 000000000072bf58 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff > R13: 0000000000000323 R14: 00000000006f4be8 R15: 0000000000000001 > > Showing all locks held in the system: > 2 locks held by kworker/1:0/17: > #0: ((wq_completion)"events"){+.+.}, at: [<00000000c9e8457d>] work_static > include/linux/workqueue.h:198 [inline] > #0: ((wq_completion)"events"){+.+.}, at: [<00000000c9e8457d>] > set_work_data kernel/workqueue.c:619 [inline] > #0: ((wq_completion)"events"){+.+.}, at: [<00000000c9e8457d>] > set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] > #0: ((wq_completion)"events"){+.+.}, at: [<00000000c9e8457d>] > process_one_work+0xb12/0x1bb0 kernel/workqueue.c:2084 > #1: ((work_completion)(&rew.rew_work)){+.+.}, at: [<000000006415d644>] > process_one_work+0xb89/0x1bb0 kernel/workqueue.c:2088 > 2 locks held by khungtaskd/800: > #0: (rcu_read_lock){....}, at: [<00000000d3e58282>] > check_hung_uninterruptible_tasks kernel/hung_task.c:175 [inline] > #0: (rcu_read_lock){....}, at: [<00000000d3e58282>] watchdog+0x1c5/0xd60 > kernel/hung_task.c:249 > #1: (tasklist_lock){.+.+}, at: [<00000000590b6074>] > debug_show_all_locks+0xd3/0x3d0 kernel/locking/lockdep.c:4470 > 3 locks held by kworker/1:2/1784: > #0: ((wq_completion)"events"){+.+.}, at: [<00000000c9e8457d>] work_static > include/linux/workqueue.h:198 [inline] > #0: ((wq_completion)"events"){+.+.}, at: [<00000000c9e8457d>] > set_work_data kernel/workqueue.c:619 [inline] > #0: ((wq_completion)"events"){+.+.}, at: [<00000000c9e8457d>] > set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] > #0: ((wq_completion)"events"){+.+.}, at: [<00000000c9e8457d>] > process_one_work+0xb12/0x1bb0 kernel/workqueue.c:2084 > #1: ((linkwatch_work).work){+.+.}, at: [<000000006415d644>] > process_one_work+0xb89/0x1bb0 kernel/workqueue.c:2088 > #2: (rtnl_mutex){+.+.}, at: [<00000000e275d2e6>] rtnl_lock+0x17/0x20 > net/core/rtnetlink.c:74 > 2 locks held by getty/4207: > #0: (&tty->ldisc_sem){++++}, at: [<000000002246b2d4>] > ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 > #1: (&ldata->atomic_read_lock){+.+.}, at: [<0000000025b60669>] > n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 > 2 locks held by getty/4208: > #0: (&tty->ldisc_sem){++++}, at: [<000000002246b2d4>] > ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 > #1: (&ldata->atomic_read_lock){+.+.}, at: [<0000000025b60669>] > n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 > 2 locks held by getty/4209: > #0: (&tty->ldisc_sem){++++}, at: [<000000002246b2d4>] > ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 > #1: (&ldata->atomic_read_lock){+.+.}, at: [<0000000025b60669>] > n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 > 2 locks held by getty/4210: > #0: (&tty->ldisc_sem){++++}, at: [<000000002246b2d4>] > ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 > #1: (&ldata->atomic_read_lock){+.+.}, at: [<0000000025b60669>] > n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 > 2 locks held by getty/4211: > #0: (&tty->ldisc_sem){++++}, at: [<000000002246b2d4>] > ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 > #1: (&ldata->atomic_read_lock){+.+.}, at: [<0000000025b60669>] > n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 > 2 locks held by getty/4212: > #0: (&tty->ldisc_sem){++++}, at: [<000000002246b2d4>] > ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 > #1: (&ldata->atomic_read_lock){+.+.}, at: [<0000000025b60669>] > n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 > 2 locks held by getty/4213: > #0: (&tty->ldisc_sem){++++}, at: [<000000002246b2d4>] > ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 > #1: (&ldata->atomic_read_lock){+.+.}, at: [<0000000025b60669>] > n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 > 3 locks held by kworker/1:3/8166: > #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000c9e8457d>] > work_static include/linux/workqueue.h:198 [inline] > #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000c9e8457d>] > set_work_data kernel/workqueue.c:619 [inline] > #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000c9e8457d>] > set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] > #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000c9e8457d>] > process_one_work+0xb12/0x1bb0 kernel/workqueue.c:2084 > #1: ((addr_chk_work).work){+.+.}, at: [<000000006415d644>] > process_one_work+0xb89/0x1bb0 kernel/workqueue.c:2088 > #2: (rtnl_mutex){+.+.}, at: [<00000000e275d2e6>] rtnl_lock+0x17/0x20 > net/core/rtnetlink.c:74 > 2 locks held by syz-executor1/22242: > #0: (rtnl_mutex){+.+.}, at: [<00000000e275d2e6>] rtnl_lock+0x17/0x20 > net/core/rtnetlink.c:74 > #1: (rcu_sched_state.exp_mutex){+.+.}, at: [<00000000675a5f13>] > exp_funnel_lock kernel/rcu/tree_exp.h:272 [inline] > #1: (rcu_sched_state.exp_mutex){+.+.}, at: [<00000000675a5f13>] > _synchronize_rcu_expedited.constprop.72+0x9fa/0xac0 > kernel/rcu/tree_exp.h:596 > 1 lock held by syz-executor1/22250: > #0: (rtnl_mutex){+.+.}, at: [<00000000e275d2e6>] rtnl_lock+0x17/0x20 > net/core/rtnetlink.c:74 > 1 lock held by syz-executor1/22253: > #0: (rtnl_mutex){+.+.}, at: [<00000000e275d2e6>] rtnl_lock+0x17/0x20 > net/core/rtnetlink.c:74 > 1 lock held by syz-executor0/22256: > #0: (rtnl_mutex){+.+.}, at: [<00000000e275d2e6>] rtnl_lock+0x17/0x20 > net/core/rtnetlink.c:74 > 1 lock held by syz-executor0/22261: > #0: (rtnl_mutex){+.+.}, at: [<00000000e275d2e6>] rtnl_lock+0x17/0x20 > net/core/rtnetlink.c:74 > 1 lock held by syz-executor0/22264: > #0: (rtnl_mutex){+.+.}, at: [<00000000e275d2e6>] rtnl_lock+0x17/0x20 > net/core/rtnetlink.c:74 > 1 lock held by syz-executor0/22265: > #0: (rtnl_mutex){+.+.}, at: [<00000000e275d2e6>] rtnl_lock+0x17/0x20 > net/core/rtnetlink.c:74 > 2 locks held by syz-executor2/22243: > #0: (&sig->cred_guard_mutex){+.+.}, at: [<00000000096b46ba>] > SYSC_perf_event_open+0x12ca/0x2e00 kernel/events/core.c:9979 > #1: (perf_sched_mutex){+.+.}, at: [<000000007096a60e>] account_event > kernel/events/core.c:9385 [inline] > #1: (perf_sched_mutex){+.+.}, at: [<000000007096a60e>] > perf_event_alloc+0x2326/0x2b00 kernel/events/core.c:9576 > 1 lock held by syz-executor2/22245: > #0: (rtnl_mutex){+.+.}, at: [<00000000e275d2e6>] rtnl_lock+0x17/0x20 > net/core/rtnetlink.c:74 > 1 lock held by syz-executor2/22259: > #0: (rtnl_mutex){+.+.}, at: [<00000000e275d2e6>] rtnl_lock+0x17/0x20 > net/core/rtnetlink.c:74 > 2 locks held by syz-executor6/22247: > #0: (&sig->cred_guard_mutex){+.+.}, at: [<00000000096b46ba>] > SYSC_perf_event_open+0x12ca/0x2e00 kernel/events/core.c:9979 > #1: (perf_sched_mutex){+.+.}, at: [<000000007096a60e>] account_event > kernel/events/core.c:9385 [inline] > #1: (perf_sched_mutex){+.+.}, at: [<000000007096a60e>] > perf_event_alloc+0x2326/0x2b00 kernel/events/core.c:9576 > 3 locks held by blkid/22275: > #0: (&bdev->bd_mutex){+.+.}, at: [<0000000012e91cb0>] > __blkdev_put+0xbc/0x760 fs/block_dev.c:1775 > #1: (loop_index_mutex){+.+.}, at: [<00000000f6fa39f1>] > lo_release+0x1f/0x190 drivers/block/loop.c:1614 > #2: (&lo->lo_ctl_mutex#2){+.+.}, at: [<00000000d468c386>] __lo_release > drivers/block/loop.c:1591 [inline] > #2: (&lo->lo_ctl_mutex#2){+.+.}, at: [<00000000d468c386>] > lo_release+0x85/0x190 drivers/block/loop.c:1615 > > ============================================= > > NMI backtrace for cpu 1 > CPU: 1 PID: 800 Comm: khungtaskd Not tainted 4.16.0-rc5+ #357 > 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+0x194/0x24d lib/dump_stack.c:53 > nmi_cpu_backtrace+0x1d2/0x210 lib/nmi_backtrace.c:103 > nmi_trigger_cpumask_backtrace+0x123/0x180 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+0x33c/0x400 kernel/kthread.c:238 > ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:406 > Sending NMI from CPU 1 to CPUs 0: > NMI backtrace for cpu 0 > CPU: 0 PID: 7 Comm: ksoftirqd/0 Not tainted 4.16.0-rc5+ #357 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS > Google 01/01/2011 > RIP: 0010:jhash2 include/linux/jhash.h:128 [inline] > RIP: 0010:hash_stack lib/stackdepot.c:161 [inline] > RIP: 0010:depot_save_stack+0x91/0x460 lib/stackdepot.c:230 > RSP: 0000:ffff8801d9ae6cb0 EFLAGS: 00000206 > RAX: 000000009be52447 RBX: 00000000c56934f1 RCX: 0000000000000006 > RDX: ffff8801d9ae6d80 RSI: 0000000001090220 RDI: ffff8801d9ae6cf0 > RBP: ffff8801d9ae6ce0 R08: 0000000000000012 R09: ffff8801d9ae6d08 > R10: 0000000026be1269 R11: 00000000c56934f1 R12: ffff880149a6a240 > R13: 0000000001090220 R14: ffff880149a6a240 R15: ffff8801dac00940 > FS: 0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 00007f382a0f3db8 CR3: 0000000006e22002 CR4: 00000000001606f0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > Call Trace: > save_stack+0xa3/0xd0 mm/kasan/kasan.c:453 > set_track mm/kasan/kasan.c:459 [inline] > kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:552 > kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:489 > slab_post_alloc_hook mm/slab.h:443 [inline] > slab_alloc_node mm/slab.c:3322 [inline] > kmem_cache_alloc_node_trace+0x139/0x760 mm/slab.c:3648 > __do_kmalloc_node mm/slab.c:3668 [inline] > __kmalloc_node_track_caller+0x33/0x70 mm/slab.c:3683 > __kmalloc_reserve.isra.39+0x41/0xd0 net/core/skbuff.c:137 > __alloc_skb+0x13b/0x780 net/core/skbuff.c:205 > alloc_skb include/linux/skbuff.h:983 [inline] > _sctp_make_chunk+0x51/0x270 net/sctp/sm_make_chunk.c:1390 > sctp_make_control+0x39/0x150 net/sctp/sm_make_chunk.c:1437 > sctp_make_heartbeat+0x90/0x420 net/sctp/sm_make_chunk.c:1151 > sctp_sf_heartbeat.isra.24+0x26/0x180 net/sctp/sm_statefuns.c:973 > sctp_sf_sendbeat_8_3+0x36b/0x520 net/sctp/sm_statefuns.c:1017 > sctp_do_sm+0x192/0x6ed0 net/sctp/sm_sideeffect.c:1178 > sctp_generate_heartbeat_event+0x292/0x3f0 net/sctp/sm_sideeffect.c:406 > call_timer_fn+0x228/0x820 kernel/time/timer.c:1326 > expire_timers kernel/time/timer.c:1363 [inline] > __run_timers+0x7ee/0xb70 kernel/time/timer.c:1666 > run_timer_softirq+0x4c/0x70 kernel/time/timer.c:1692 > __do_softirq+0x2d7/0xb85 kernel/softirq.c:285 > run_ksoftirqd+0x86/0x100 kernel/softirq.c:666 > smpboot_thread_fn+0x450/0x7c0 kernel/smpboot.c:164 > kthread+0x33c/0x400 kernel/kthread.c:238 > ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:406 > Code: 45 31 da 44 29 d0 41 89 c3 44 89 d0 41 01 da c1 c0 06 44 31 d8 29 c3 > 41 89 db 89 c3 44 01 d0 c1 c3 08 44 31 db 41 89 db 41 29 da <01> c3 41 c1 c3 > 10 45 31 da 45 89 d3 44 29 d0 41 01 da 41 c1 cb > > > --- > This bug is generated by a dumb bot. It may contain errors. > See https://goo.gl/tpsmEJ for details. > Direct all questions to syzkal...@googlegroups.com. > > syzbot will keep track of this bug report. > If you forgot to add the Reported-by tag, once the fix for this bug is > merged > into any tree, please 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+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/syzkaller-bugs/001a1135b9dafc2a150567be19e9%40google.com. > For more options, visit https://groups.google.com/d/optout.