INFO: task syz-executor.4:12983 blocked for more than 143 seconds. Not tainted 5.16.0-rc7-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.4 state:D stack:27992 pid:12983 ppid: 3639 flags:0x00024004 Call Trace: context_switch kernel/sched/core.c:4972 [inline] __schedule+0xa9a/0x4900 kernel/sched/core.c:6253 schedule+0xd2/0x260 kernel/sched/core.c:6326 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6385 __mutex_lock_common kernel/locking/mutex.c:680 [inline] __mutex_lock+0xa32/0x12f0 kernel/locking/mutex.c:740 io_uring_del_tctx_node+0x109/0x20a fs/io_uring.c:9781 io_uring_clean_tctx fs/io_uring.c:9797 [inline] io_uring_cancel_generic+0x5da/0x695 fs/io_uring.c:9888 io_uring_files_cancel include/linux/io_uring.h:16 [inline] do_exit+0x60c/0x2b40 kernel/exit.c:787 do_group_exit+0x125/0x310 kernel/exit.c:929 get_signal+0x47d/0x2220 kernel/signal.c:2852 arch_do_signal_or_restart+0x2a9/0x1c40 arch/x86/kernel/signal.c:868 handle_signal_work kernel/entry/common.c:148 [inline] exit_to_user_mode_loop kernel/entry/common.c:172 [inline] exit_to_user_mode_prepare+0x17d/0x290 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f9846319e99 RSP: 002b:00007f9844c0b168 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: 0000000000001000 RBX: 00007f984642d2a0 RCX: 00007f9846319e99 RDX: 0000000000000000 RSI: 000000000000688c RDI: 0000000000000003 RBP: 00007f9846373ff1 R08: 0000000000000000 R09: 000000000000fc00 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fffbcedf7bf R14: 00007f9844c0b300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8bb812a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6458 2 locks held by getty/3286: #0: ffff88807f274098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:252 #1: ffffc90002b8e2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xcf0/0x1230 drivers/tty/n_tty.c:2113 2 locks held by syz-executor.4/12972: 1 lock held by syz-executor.4/12983: #0: ffff8880292c70a8 (&ctx->uring_lock){+.+.}-{3:3}, at: io_uring_del_tctx_node+0x109/0x20a fs/io_uring.c:9781 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.16.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline] watchdog+0xc1d/0xf50 kernel/hung_task.c:295 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 12972 Comm: syz-executor.4 Not tainted 5.16.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__debug_check_no_obj_freed lib/debugobjects.c:984 [inline] RIP: 0010:debug_check_no_obj_freed+0x136/0x420 lib/debugobjects.c:1023 Code: 49 8d 78 18 41 83 c4 01 49 8b 28 48 89 f8 48 c1 e8 03 42 80 3c 38 00 0f 85 30 02 00 00 4d 8b 48 18 4c 39 cb 0f 87 8e 00 00 00 <4c> 3b 0c 24 0f 83 84 00 00 00 49 8d 78 10 48 89 f8 48 c1 e8 03 42 RSP: 0018:ffffc9000549fce8 EFLAGS: 00000097 RAX: 1ffff1100e6248ea RBX: ffff888029dab300 RCX: ffffffff815c4e40 RDX: 1ffffffff20cc646 RSI: 0000000000000004 RDI: ffff888073124750 RBP: ffff88802b5b9268 R08: ffff888073124738 R09: ffff888029dabd88 R10: fffff52000a93f8b R11: 0000000000000001 R12: 0000000000000004 R13: dead000000000122 R14: dead000000000100 R15: dffffc0000000000 FS: 00007f9844c8f700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c012372570 CR3: 000000008e32b000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: kfree+0xd4/0x2c0 mm/slab.c:3801 io_clean_op+0x468/0xba0 fs/io_uring.c:6651 io_dismantle_req fs/io_uring.c:2064 [inline] io_req_complete_post+0x5dc/0x820 fs/io_uring.c:1911 tctx_task_work+0x1b3/0x630 fs/io_uring.c:2245 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 tracehook_notify_signal include/linux/tracehook.h:214 [inline] handle_signal_work kernel/entry/common.c:146 [inline] exit_to_user_mode_loop kernel/entry/common.c:172 [inline] exit_to_user_mode_prepare+0x256/0x290 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f9846319e99 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f9844c8f168 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: 0000000000001000 RBX: 00007f984642cf60 RCX: 00007f9846319e99 RDX: 0000000000000000 RSI: 000000000000688c RDI: 0000000000000003 RBP: 00007f9846373ff1 R08: 0000000000000000 R09: 000000000000fc00 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fffbcedf7bf R14: 00007f9844c8f300 R15: 0000000000022000 ---------------- Code disassembly (best guess): 0: 49 8d 78 18 lea 0x18(%r8),%rdi 4: 41 83 c4 01 add $0x1,%r12d 8: 49 8b 28 mov (%r8),%rbp b: 48 89 f8 mov %rdi,%rax e: 48 c1 e8 03 shr $0x3,%rax 12: 42 80 3c 38 00 cmpb $0x0,(%rax,%r15,1) 17: 0f 85 30 02 00 00 jne 0x24d 1d: 4d 8b 48 18 mov 0x18(%r8),%r9 21: 4c 39 cb cmp %r9,%rbx 24: 0f 87 8e 00 00 00 ja 0xb8 * 2a: 4c 3b 0c 24 cmp (%rsp),%r9 <-- trapping instruction 2e: 0f 83 84 00 00 00 jae 0xb8 34: 49 8d 78 10 lea 0x10(%r8),%rdi 38: 48 89 f8 mov %rdi,%rax 3b: 48 c1 e8 03 shr $0x3,%rax 3f: 42 rex.X