INFO: task syz-executor.1:2137 blocked for more than 143 seconds. Not tainted 6.1.74-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.1 state:D stack:27560 pid:2137 ppid:3559 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x142d/0x4550 kernel/sched/core.c:6558 schedule+0xbf/0x180 kernel/sched/core.c:6634 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6693 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x6b9/0xd80 kernel/locking/mutex.c:747 blkdev_put+0x100/0x750 block/bdev.c:913 blkdev_close+0x56/0x80 block/fops.c:514 __fput+0x3b7/0x890 fs/file_table.c:320 task_work_run+0x246/0x300 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xde/0x100 kernel/entry/common.c:171 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:297 do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fa88787cda9 RSP: 002b:00007fa8885a40c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: 0000000000000000 RBX: 00007fa8879abf80 RCX: 00007fa88787cda9 RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003 RBP: 00007fa8878c947a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007fa8879abf80 R15: 00007ffffd049bc8 Showing all locks held in the system: 2 locks held by kworker/u4:1/11: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8d12a490 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516 1 lock held by rcu_tasks_trace/13: #0: ffffffff8d12ac90 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516 1 lock held by khungtaskd/28: #0: ffffffff8d12a2c0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:306 [inline] #0: ffffffff8d12a2c0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:747 [inline] #0: ffffffff8d12a2c0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6494 2 locks held by getty/3305: #0: ffff88814b182098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc900031262f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a7/0x1db0 drivers/tty/n_tty.c:2188 1 lock held by udevd/32549: #0: ffff88801ffd34c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x148/0xa10 block/bdev.c:815 1 lock held by udevd/32556: #0: ffff888142f284c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x148/0xa10 block/bdev.c:815 1 lock held by syz-executor.1/2137: #0: ffff888142f284c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0x100/0x750 block/bdev.c:913 1 lock held by syz-executor.0/2260: #0: ffff88801ffd34c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0x100/0x750 block/bdev.c:913 1 lock held by syz-executor.1/2395: #0: ffff888142f284c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x148/0xa10 block/bdev.c:815 1 lock held by syz-executor.1/2403: #0: ffff888142f284c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x148/0xa10 block/bdev.c:815 1 lock held by syz-executor.0/2523: #0: ffff88801ffd34c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x148/0xa10 block/bdev.c:815 1 lock held by syz-executor.1/2639: #0: ffff888142f284c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x148/0xa10 block/bdev.c:815 1 lock held by syz-executor.0/2760: #0: ffff88801ffd34c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x148/0xa10 block/bdev.c:815 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.1.74-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 nmi_cpu_backtrace+0x4e1/0x560 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1b0/0x3f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xf88/0xfd0 kernel/hung_task.c:377 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 2991 Comm: klogd Not tainted 6.1.74-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 RIP: 0010:memcpy_erms+0x8/0x10 arch/x86/lib/memcpy_64.S:57 Code: ff cc eb 1e 0f 1f 00 48 89 f8 48 89 d1 48 c1 e9 03 83 e2 07 f3 48 a5 89 d1 f3 a4 c3 66 0f 1f 44 00 00 48 89 f8 48 89 d1 f3 a4 0f 1f 80 00 00 00 00 48 89 f8 48 83 fa 20 72 7e 40 38 fe 7c 35 RSP: 0018:ffffc900001e06b8 EFLAGS: 00000202 RAX: ffff888051e2e800 RBX: 0000000000000010 RCX: 0000000000000000 RDX: 0000000000000010 RSI: ffff88807c600258 RDI: ffff888051e2e810 RBP: ffffc900001e0800 R08: dffffc0000000000 R09: ffffed100a3c5d02 R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888051e2e800 R13: 00000000fffffff0 R14: 1ffff1100f8c003a R15: 0000000000000000 FS: 00007f7cfa0a1380(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f4b649a8440 CR3: 0000000026456000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: neigh_hh_output include/net/neighbour.h:509 [inline] neigh_output include/net/neighbour.h:542 [inline] ip6_finish_output2+0xcb4/0x1520 net/ipv6/ip6_output.c:134 __ip6_finish_output net/ipv6/ip6_output.c:201 [inline] ip6_finish_output+0x6a0/0xa80 net/ipv6/ip6_output.c:212 dst_output include/net/dst.h:444 [inline] NF_HOOK include/linux/netfilter.h:302 [inline] ndisc_send_skb+0xbab/0x14e0 net/ipv6/ndisc.c:509 addrconf_rs_timer+0x357/0x610 net/ipv6/addrconf.c:3946 call_timer_fn+0x1ad/0x6b0 kernel/time/timer.c:1474 expire_timers kernel/time/timer.c:1519 [inline] __run_timers+0x67c/0x890 kernel/time/timer.c:1790 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1803 __do_softirq+0x2e9/0xa4c kernel/softirq.c:571 invoke_softirq kernel/softirq.c:445 [inline] __irq_exit_rcu+0x155/0x240 kernel/softirq.c:650 irq_exit_rcu+0x5/0x20 kernel/softirq.c:662 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653 RIP: 0010:___slab_alloc+0x109f/0x1270 Code: c7 44 24 70 00 00 00 00 9c 8f 44 24 70 f7 44 24 70 00 02 00 00 75 40 41 f7 c4 00 02 00 00 74 01 fb 65 48 8b 04 25 28 00 00 00 <48> 3b 44 24 78 0f 85 f9 00 00 00 4c 89 f8 48 81 c4 80 00 00 00 5b RSP: 0018:ffffc90002f6f758 EFLAGS: 00000206 RAX: 6c62be86636aae00 RBX: ffff8880b9943130 RCX: ffffffff91c89103 RDX: dffffc0000000000 RSI: ffffffff8aebe640 RDI: ffffffff8b3cfa80 RBP: 0000000000000001 R08: dffffc0000000000 R09: fffffbfff1ce6a16 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000246 R13: ffff888014a50500 R14: ffff8880b9943110 R15: ffff88804849ddc0 __slab_alloc mm/slub.c:3279 [inline] slab_alloc_node mm/slub.c:3364 [inline] kmem_cache_alloc_node+0x1cf/0x310 mm/slub.c:3443 __alloc_skb+0xde/0x670 net/core/skbuff.c:505 alloc_skb include/linux/skbuff.h:1276 [inline] alloc_skb_with_frags+0xa4/0x740 net/core/skbuff.c:6156 sock_alloc_send_pskb+0x915/0xa50 net/core/sock.c:2745 unix_dgram_sendmsg+0x5b1/0x2050 net/unix/af_unix.c:1941 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:730 [inline] __sys_sendto+0x480/0x600 net/socket.c:2148 __do_sys_sendto net/socket.c:2160 [inline] __se_sys_sendto net/socket.c:2156 [inline] __x64_sys_sendto+0xda/0xf0 net/socket.c:2156 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f7cfa2039b5 Code: 8b 44 24 08 48 83 c4 28 48 98 c3 48 98 c3 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 26 45 31 c9 45 31 c0 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 7a 48 8b 15 44 c4 0c 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffe7e2391d8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f7cfa2039b5 RDX: 0000000000000046 RSI: 0000560cfcc3fe00 RDI: 0000000000000003 RBP: 0000560cfcc39910 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000004000 R11: 0000000000000246 R12: 0000000000000013 R13: 00007f7cfa391212 R14: 00007ffe7e2392d8 R15: 0000000000000000