INFO: task syz-executor.3:7661 blocked for more than 143 seconds. Not tainted 6.9.0-rc6-syzkaller-00046-g18daea77cca6 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.3 state:D stack:26488 pid:7661 tgid:7658 ppid:6931 flags:0x00000006 Call Trace: context_switch kernel/sched/core.c:5409 [inline] __schedule+0x1796/0x4a00 kernel/sched/core.c:6746 __schedule_loop kernel/sched/core.c:6823 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6838 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6895 rwsem_down_write_slowpath+0xeeb/0x13b0 kernel/locking/rwsem.c:1178 __down_write_common+0x1af/0x200 kernel/locking/rwsem.c:1306 inode_lock include/linux/fs.h:795 [inline] chown_common+0x3e1/0x850 fs/open.c:780 vfs_fchown fs/open.c:858 [inline] ksys_fchown+0xea/0x160 fs/open.c:869 __do_sys_fchown fs/open.c:877 [inline] __se_sys_fchown fs/open.c:875 [inline] __x64_sys_fchown+0x7a/0x90 fs/open.c:875 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7eba07dea9 RSP: 002b:00007f7ebad3a0c8 EFLAGS: 00000246 ORIG_RAX: 000000000000005d RAX: ffffffffffffffda RBX: 00007f7eba1ac050 RCX: 00007f7eba07dea9 RDX: 000000000000000a RSI: ffffffffffffffff RDI: 0000000000000006 RBP: 00007f7eba0ca4a4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f7eba1ac050 R15: 00007ffd20453728 Showing all locks held in the system: 3 locks held by kworker/1:0/24: #0: ffff888015080948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3242 [inline] #0: ffff888015080948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x8e0/0x17c0 kernel/workqueue.c:3348 #1: ffffc900001e7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3243 [inline] #1: ffffc900001e7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x91b/0x17c0 kernel/workqueue.c:3348 #2: ffffffff8f594488 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 1 lock held by khungtaskd/29: #0: ffffffff8e334d60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #0: ffffffff8e334d60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #0: ffffffff8e334d60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6614 5 locks held by kworker/u8:2/34: #0: ffff888015ecb148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3242 [inline] #0: ffff888015ecb148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x8e0/0x17c0 kernel/workqueue.c:3348 #1: ffffc90000aa7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3243 [inline] #1: ffffc90000aa7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x91b/0x17c0 kernel/workqueue.c:3348 #2: ffffffff8f587d90 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:591 #3: ffffffff8f594488 (rtnl_mutex){+.+.}-{3:3}, at: default_device_exit_batch+0xe9/0xa90 net/core/dev.c:11626 #4: ffffffff8e33a0f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline] #4: ffffffff8e33a0f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x39a/0x820 kernel/rcu/tree_exp.h:939 1 lock held by dhcpcd/4744: #0: ffffffff8f594488 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x2ce/0x1bc0 net/ipv4/devinet.c:1096 2 locks held by getty/4837: #0: ffff88802f5510a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000312b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b5/0x1e10 drivers/tty/n_tty.c:2201 1 lock held by syz-executor.0/7386: #0: ffffffff8f594488 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8f594488 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3e/0x1b0 drivers/net/tun.c:3500 2 locks held by syz-executor.3/7661: #0: ffff888025412420 (sb_writers#33){.+.+}-{0:0}, at: mnt_want_write_file+0x61/0x200 fs/namespace.c:453 #1: ffff88805d0e8188 (&type->i_mutex_dir_key#21){++++}-{3:3}, at: inode_lock include/linux/fs.h:795 [inline] #1: ffff88805d0e8188 (&type->i_mutex_dir_key#21){++++}-{3:3}, at: chown_common+0x3e1/0x850 fs/open.c:780 1 lock held by syz-executor.3/7662: 1 lock held by syz-executor.2/7832: #0: ffff8880b953e658 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:559 1 lock held by syz-executor.4/9885: #0: ffffffff8f594488 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f594488 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x842/0x10d0 net/core/rtnetlink.c:6592 3 locks held by syz-executor.3/9973: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: khungtaskd Not tainted 6.9.0-rc6-syzkaller-00046-g18daea77cca6 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xfde/0x1020 kernel/hung_task.c:380 kthread+0x2f0/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 9973 Comm: syz-executor.3 Not tainted 6.9.0-rc6-syzkaller-00046-g18daea77cca6 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 RIP: 0010:__sanitizer_cov_trace_pc+0x46/0x70 kernel/kcov.c:212 Code: ff 00 74 11 f7 c2 00 01 00 00 74 35 83 b9 14 16 00 00 00 74 2c 8b 91 f0 15 00 00 83 fa 02 75 21 48 8b 91 f8 15 00 00 48 8b 32 <48> 8d 7e 01 8b 89 f4 15 00 00 48 39 cf 73 08 48 89 3a 48 89 44 f2 RSP: 0018:ffffc900046b5fd0 EFLAGS: 00000246 RAX: ffffffff81414dcc RBX: ffffc900046b6000 RCX: ffff88805dc81e00 RDX: ffffc90011b44000 RSI: 000000000003ffff RDI: ffffc900046b6000 RBP: ffffc900046b6090 R08: ffffffff81416de5 R09: ffffffff814168df R10: 0000000000000003 R11: ffff88805dc81e00 R12: ffff88805dc81e00 R13: ffffffff8181f070 R14: dffffc0000000000 R15: ffffc900046b6000 FS: 00007f54c6f896c0(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055b39e890560 CR3: 000000006272a000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: unwind_get_return_address+0x1c/0xc0 arch/x86/kernel/unwind_orc.c:365 arch_stack_walk+0x125/0x1b0 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579 poison_slab_object+0xa6/0xe0 mm/kasan/common.c:240 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2106 [inline] slab_free mm/slub.c:4280 [inline] kmem_cache_free+0x10b/0x2c0 mm/slub.c:4344 free_buffer_head+0x55/0x240 fs/buffer.c:3017 try_to_free_buffers+0x311/0x5f0 fs/buffer.c:2958 shrink_folio_list+0x273f/0x8ca0 mm/vmscan.c:1376 shrink_inactive_list mm/vmscan.c:1926 [inline] shrink_list mm/vmscan.c:2163 [inline] shrink_lruvec+0x1638/0x2e40 mm/vmscan.c:5687 shrink_node_memcgs mm/vmscan.c:5873 [inline] shrink_node+0x1189/0x2d60 mm/vmscan.c:5908 shrink_zones mm/vmscan.c:6152 [inline] do_try_to_free_pages+0x695/0x1af0 mm/vmscan.c:6214 try_to_free_mem_cgroup_pages+0x47a/0xad0 mm/vmscan.c:6529 try_charge_memcg+0x6da/0x18a0 mm/memcontrol.c:2783 try_charge mm/memcontrol.c:2931 [inline] charge_memcg+0xa2/0x160 mm/memcontrol.c:7284 __mem_cgroup_charge+0x27/0x80 mm/memcontrol.c:7299 mem_cgroup_charge include/linux/memcontrol.h:691 [inline] shmem_alloc_and_add_folio+0x456/0xbc0 mm/shmem.c:1677 shmem_get_folio_gfp+0x82d/0x1f50 mm/shmem.c:2055 shmem_get_folio mm/shmem.c:2160 [inline] shmem_write_begin+0x170/0x4d0 mm/shmem.c:2744 generic_perform_write+0x322/0x640 mm/filemap.c:3974 shmem_file_write_iter+0xfc/0x120 mm/shmem.c:2920 call_write_iter include/linux/fs.h:2110 [inline] new_sync_write fs/read_write.c:497 [inline] vfs_write+0xa84/0xcb0 fs/read_write.c:590 ksys_write+0x1a0/0x2c0 fs/read_write.c:643 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f54c627cbef Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 b9 80 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 0c 81 02 00 48 RSP: 002b:00007f54c6f88e80 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00000000013bd7ef RCX: 00007f54c627cbef RDX: 00000000013bd7ef RSI: 00007f54bc000000 RDI: 0000000000000006 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000005503 R10: 00000000000003ce R11: 0000000000000293 R12: 0000000000000006 R13: 00007f54c6f88f80 R14: 00007f54c6f88f40 R15: 00007f54bc000000