================================ WARNING: inconsistent lock state 6.7.0-rc1-next-20231117-syzkaller #0 Not tainted -------------------------------- inconsistent {HARDIRQ-ON-W} -> {IN-HARDIRQ-W} usage. syz-executor.1/22701 [HC1[1]:SC0[0]:HE0:SE1] takes: ffff88803fbce5d8 (&sighand->siglock){?.+.}-{2:2}, at: __lock_task_sighand+0xc2/0x340 kernel/signal.c:1422 {HARDIRQ-ON-W} state was registered at: lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1b1/0x530 kernel/locking/lockdep.c:5718 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] class_spinlock_constructor include/linux/spinlock.h:530 [inline] ptrace_set_stopped kernel/ptrace.c:391 [inline] ptrace_attach+0x401/0x650 kernel/ptrace.c:478 __do_sys_ptrace+0x204/0x230 kernel/ptrace.c:1290 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x40/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x62/0x6a irq event stamp: 66 hardirqs last enabled at (65): [] __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:159 [inline] hardirqs last enabled at (65): [] _raw_spin_unlock_irq+0x23/0x50 kernel/locking/spinlock.c:202 hardirqs last disabled at (66): [] sysvec_apic_timer_interrupt+0xe/0xb0 arch/x86/kernel/apic/apic.c:1076 softirqs last enabled at (0): [] copy_process+0x244c/0x9770 kernel/fork.c:2466 softirqs last disabled at (0): [<0000000000000000>] 0x0 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&sighand->siglock); lock(&sighand->siglock); *** DEADLOCK *** 2 locks held by syz-executor.1/22701: #0: ffffffff8cfad060 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:301 [inline] #0: ffffffff8cfad060 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:747 [inline] #0: ffffffff8cfad060 (rcu_read_lock){....}-{1:2}, at: kill_pid_info+0x22/0x2a0 kernel/signal.c:1496 #1: ffffffff8cfad060 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:301 [inline] #1: ffffffff8cfad060 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:747 [inline] #1: ffffffff8cfad060 (rcu_read_lock){....}-{1:2}, at: __lock_task_sighand+0x3f/0x340 kernel/signal.c:1405 stack backtrace: CPU: 1 PID: 22701 Comm: syz-executor.1 Not tainted 6.7.0-rc1-next-20231117-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 print_usage_bug kernel/locking/lockdep.c:3970 [inline] valid_state kernel/locking/lockdep.c:4012 [inline] mark_lock_irq kernel/locking/lockdep.c:4215 [inline] mark_lock+0x91a/0xc50 kernel/locking/lockdep.c:4677 mark_usage kernel/locking/lockdep.c:4563 [inline] __lock_acquire+0x1347/0x3b10 kernel/locking/lockdep.c:5090 lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1b1/0x530 kernel/locking/lockdep.c:5718 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x50 kernel/locking/spinlock.c:162 __lock_task_sighand+0xc2/0x340 kernel/signal.c:1422 lock_task_sighand include/linux/sched/signal.h:748 [inline] do_send_sig_info kernel/signal.c:1309 [inline] group_send_sig_info+0x288/0x300 kernel/signal.c:1460 kill_pid_info+0x95/0x2a0 kernel/signal.c:1499 it_real_fn+0xbc/0x230 kernel/time/itimer.c:163 __run_hrtimer kernel/time/hrtimer.c:1688 [inline] __hrtimer_run_queues+0x20c/0xc20 kernel/time/hrtimer.c:1752 hrtimer_interrupt+0x31b/0x800 kernel/time/hrtimer.c:1814 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1065 [inline] __sysvec_apic_timer_interrupt+0x10c/0x410 arch/x86/kernel/apic/apic.c:1082 sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1076 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline] RIP: 0010:_raw_spin_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:202 Code: 90 f3 0f 1e fa 53 48 8b 74 24 08 48 89 fb 48 83 c7 18 e8 6a c8 e3 f6 48 89 df e8 22 40 e4 f6 e8 7d 25 0a f7 fb bf 01 00 00 00 e2 ed d5 f6 65 8b 05 03 19 7f 75 85 c0 74 02 5b c3 e8 f0 dc 7b RSP: 0018:ffffc9000d3d7d70 EFLAGS: 00000206 RAX: 0000000000000041 RBX: ffff88803fbce5c0 RCX: 1ffffffff1e31619 RDX: 0000000000000000 RSI: ffffffff8accbfe0 RDI: 0000000000000001 RBP: ffffc9000d3d7de0 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff8f18e357 R11: 0000000000000002 R12: ffff88801ff82950 R13: ffff88801f75bb80 R14: 0000000000000bb8 R15: 0000000000000000 spin_unlock_irq include/linux/spinlock.h:401 [inline] do_setitimer+0x410/0x580 kernel/time/itimer.c:238 __do_sys_setitimer kernel/time/itimer.c:349 [inline] __se_sys_setitimer kernel/time/itimer.c:332 [inline] __x64_sys_setitimer+0x31a/0x360 kernel/time/itimer.c:332 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x40/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x62/0x6a RIP: 0033:0x7f0798c7cae9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f079995d0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000026 RAX: ffffffffffffffda RBX: 00007f0798d9bf80 RCX: 00007f0798c7cae9 RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000000 RBP: 00007f0798cc847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f0798d9bf80 R15: 00007ffee3b11348 ---------------- Code disassembly (best guess): 0: 90 nop 1: f3 0f 1e fa endbr64 5: 53 push %rbx 6: 48 8b 74 24 08 mov 0x8(%rsp),%rsi b: 48 89 fb mov %rdi,%rbx e: 48 83 c7 18 add $0x18,%rdi 12: e8 6a c8 e3 f6 call 0xf6e3c881 17: 48 89 df mov %rbx,%rdi 1a: e8 22 40 e4 f6 call 0xf6e44041 1f: e8 7d 25 0a f7 call 0xf70a25a1 24: fb sti 25: bf 01 00 00 00 mov $0x1,%edi * 2a: e8 e2 ed d5 f6 call 0xf6d5ee11 <-- trapping instruction 2f: 65 8b 05 03 19 7f 75 mov %gs:0x757f1903(%rip),%eax # 0x757f1939 36: 85 c0 test %eax,%eax 38: 74 02 je 0x3c 3a: 5b pop %rbx 3b: c3 ret 3c: e8 .byte 0xe8 3d: f0 lock 3e: dc .byte 0xdc 3f: 7b .byte 0x7b