======================================================== WARNING: possible irq lock inversion dependency detected 6.7.0-rc1-next-20231117-syzkaller #0 Not tainted -------------------------------------------------------- syz-executor.1/14754 just changed the state of lock: ffff888078a32a80 (&new_timer->it_lock){-...}-{2:2}, at: posix_timer_fn+0x2d/0x3d0 kernel/time/posix-timers.c:318 but this lock took another, HARDIRQ-unsafe lock in the past: (&sighand->siglock){+.+.}-{2:2} and interrupts could create inverse lock ordering between them. other info that might help us debug this: Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&sighand->siglock); local_irq_disable(); lock(&new_timer->it_lock); lock(&sighand->siglock); lock(&new_timer->it_lock); *** DEADLOCK *** no locks held by syz-executor.1/14754. the shortest dependencies between 2nd lock and 1st lock: -> (&sighand->siglock){+.+.}-{2:2} { HARDIRQ-ON-W 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 SOFTIRQ-ON-W 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 INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1b1/0x530 kernel/locking/lockdep.c:5718 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline] _raw_spin_lock_irq+0x36/0x50 kernel/locking/spinlock.c:170 spin_lock_irq include/linux/spinlock.h:376 [inline] calculate_sigpending+0x44/0xa0 kernel/signal.c:197 ret_from_fork+0x23/0x80 arch/x86/kernel/process.c:143 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 } ... key at: [] __key.341+0x0/0x40 ... acquired at: __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] __do_sys_timer_delete kernel/time/posix-timers.c:1023 [inline] __se_sys_timer_delete kernel/time/posix-timers.c:1006 [inline] __x64_sys_timer_delete+0x16a/0x3e0 kernel/time/posix-timers.c:1006 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 -> (&new_timer->it_lock){-...}-{2:2} { IN-HARDIRQ-W at: 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 posix_timer_fn+0x2d/0x3d0 kernel/time/posix-timers.c:318 __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 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline] _raw_spin_unlock_irqrestore+0x31/0x70 kernel/locking/spinlock.c:194 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] unlock_timer kernel/time/posix-timers.c:128 [inline] do_timer_settime+0x260/0x2f0 kernel/time/posix-timers.c:934 __do_sys_timer_settime kernel/time/posix-timers.c:954 [inline] __se_sys_timer_settime kernel/time/posix-timers.c:940 [inline] __x64_sys_timer_settime+0x266/0x2c0 kernel/time/posix-timers.c:940 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 INITIAL USE at: 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_timer+0x20d/0x4c0 kernel/time/posix-timers.c:595 do_timer_gettime+0x76/0x180 kernel/time/posix-timers.c:703 __do_sys_timer_gettime kernel/time/posix-timers.c:724 [inline] __se_sys_timer_gettime kernel/time/posix-timers.c:719 [inline] __x64_sys_timer_gettime+0xd5/0x170 kernel/time/posix-timers.c:719 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 } ... key at: [] __key.0+0x0/0x40 ... acquired at: 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 posix_timer_fn+0x2d/0x3d0 kernel/time/posix-timers.c:318 __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 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline] _raw_spin_unlock_irqrestore+0x31/0x70 kernel/locking/spinlock.c:194 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] unlock_timer kernel/time/posix-timers.c:128 [inline] do_timer_settime+0x260/0x2f0 kernel/time/posix-timers.c:934 __do_sys_timer_settime kernel/time/posix-timers.c:954 [inline] __se_sys_timer_settime kernel/time/posix-timers.c:940 [inline] __x64_sys_timer_settime+0x266/0x2c0 kernel/time/posix-timers.c:940 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 stack backtrace: CPU: 1 PID: 14754 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_irq_inversion_bug.part.0+0x3e1/0x590 kernel/locking/lockdep.c:4079 print_irq_inversion_bug kernel/locking/lockdep.c:4032 [inline] check_usage_forwards kernel/locking/lockdep.c:4110 [inline] mark_lock_irq kernel/locking/lockdep.c:4242 [inline] mark_lock+0x570/0xc50 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 posix_timer_fn+0x2d/0x3d0 kernel/time/posix-timers.c:318 __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_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x70 kernel/locking/spinlock.c:194 Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 16 c8 e3 f6 48 89 df e8 ce 3f e4 f6 f7 c5 00 02 00 00 75 1f 9c 58 f6 c4 02 75 2f 01 00 00 00 e8 85 ed d5 f6 65 8b 05 a6 18 7f 75 85 c0 74 12 5b RSP: 0018:ffffc900033a7d70 EFLAGS: 00000246 RAX: 0000000000000006 RBX: ffff888078a32a68 RCX: 1ffffffff1e31619 RDX: 0000000000000000 RSI: ffffffff8accbfe0 RDI: ffffffff8b2f1520 RBP: 0000000000000287 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff8f18e357 R11: 0000000000000002 R12: 0000000000000000 R13: 1ffff92000674fb3 R14: ffffffff81789850 R15: dffffc0000000000 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] unlock_timer kernel/time/posix-timers.c:128 [inline] do_timer_settime+0x260/0x2f0 kernel/time/posix-timers.c:934 __do_sys_timer_settime kernel/time/posix-timers.c:954 [inline] __se_sys_timer_settime kernel/time/posix-timers.c:940 [inline] __x64_sys_timer_settime+0x266/0x2c0 kernel/time/posix-timers.c:940 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: 0033:0x7fee19e7cae9 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:00007fee189fe0c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000df RAX: ffffffffffffffda RBX: 00007fee19f9c050 RCX: 00007fee19e7cae9 RDX: 00000000200000c0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007fee19ec847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007fee19f9c050 R15: 00007ffdb0199ff8 ---------------- Code disassembly (best guess): 0: f5 cmc 1: 53 push %rbx 2: 48 8b 74 24 10 mov 0x10(%rsp),%rsi 7: 48 89 fb mov %rdi,%rbx a: 48 83 c7 18 add $0x18,%rdi e: e8 16 c8 e3 f6 call 0xf6e3c829 13: 48 89 df mov %rbx,%rdi 16: e8 ce 3f e4 f6 call 0xf6e43fe9 1b: f7 c5 00 02 00 00 test $0x200,%ebp 21: 75 1f jne 0x42 23: 9c pushf 24: 58 pop %rax 25: f6 c4 02 test $0x2,%ah 28: 75 2f jne 0x59 * 2a: bf 01 00 00 00 mov $0x1,%edi <-- trapping instruction 2f: e8 85 ed d5 f6 call 0xf6d5edb9 34: 65 8b 05 a6 18 7f 75 mov %gs:0x757f18a6(%rip),%eax # 0x757f18e1 3b: 85 c0 test %eax,%eax 3d: 74 12 je 0x51 3f: 5b pop %rbx