======================================================== WARNING: possible irq lock inversion dependency detected 6.8.0-syzkaller-08951-gfe46a7dd189e #0 Not tainted -------------------------------------------------------- syz-executor.3/8090 just changed the state of lock: ffff88802a1d4110 (&group->lock#2){..-.}-{2:2}, at: _snd_pcm_stream_lock_irqsave+0xa0/0xd0 sound/core/pcm_native.c:170 but this lock took another, SOFTIRQ-unsafe lock in the past: (&timer->lock){+.+.}-{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(&timer->lock); local_irq_disable(); lock(&group->lock#2); lock(&timer->lock); lock(&group->lock#2); *** DEADLOCK *** 3 locks held by syz-executor.3/8090: #0: ffff888029aaa420 (sb_writers#5){.+.+}-{0:0}, at: filename_create+0x10d/0x530 fs/namei.c:3885 #1: ffff88805c564a00 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:828 [inline] #1: ffff88805c564a00 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: filename_create+0x1c2/0x530 fs/namei.c:3892 #2: ffffffff8e11e410 (tomoyo_ss){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:116 [inline] #2: ffffffff8e11e410 (tomoyo_ss){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:215 [inline] #2: ffffffff8e11e410 (tomoyo_ss){.+.+}-{0:0}, at: tomoyo_read_lock security/tomoyo/common.h:1108 [inline] #2: ffffffff8e11e410 (tomoyo_ss){.+.+}-{0:0}, at: tomoyo_path_perm+0x25f/0x450 security/tomoyo/file.c:821 the shortest dependencies between 2nd lock and 1st lock: -> (&timer->lock){+.+.}-{2:2} { HARDIRQ-ON-W at: lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719 __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:561 [inline] snd_timer_close_locked+0x65/0xbd0 sound/core/timer.c:412 snd_timer_close+0x8b/0xf0 sound/core/timer.c:464 snd_seq_timer_close+0xa4/0x100 sound/core/seq/seq_timer.c:302 queue_delete+0x49/0xa0 sound/core/seq/seq_queue.c:126 snd_seq_queue_client_leave+0x37/0x1a0 sound/core/seq/seq_queue.c:543 seq_free_client1.part.0+0x10a/0x260 sound/core/seq/seq_clientmgr.c:285 seq_free_client1 sound/core/seq/seq_clientmgr.c:278 [inline] seq_free_client+0x74/0x170 sound/core/seq/seq_clientmgr.c:306 snd_seq_release+0x50/0xe0 sound/core/seq/seq_clientmgr.c:387 __fput+0x270/0xb80 fs/file_table.c:422 __fput_sync+0x47/0x50 fs/file_table.c:507 __do_sys_close fs/open.c:1556 [inline] __se_sys_close fs/open.c:1541 [inline] __x64_sys_close+0x86/0x100 fs/open.c:1541 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6d/0x75 SOFTIRQ-ON-W at: lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719 __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:561 [inline] snd_timer_close_locked+0x65/0xbd0 sound/core/timer.c:412 snd_timer_close+0x8b/0xf0 sound/core/timer.c:464 snd_seq_timer_close+0xa4/0x100 sound/core/seq/seq_timer.c:302 queue_delete+0x49/0xa0 sound/core/seq/seq_queue.c:126 snd_seq_queue_client_leave+0x37/0x1a0 sound/core/seq/seq_queue.c:543 seq_free_client1.part.0+0x10a/0x260 sound/core/seq/seq_clientmgr.c:285 seq_free_client1 sound/core/seq/seq_clientmgr.c:278 [inline] seq_free_client+0x74/0x170 sound/core/seq/seq_clientmgr.c:306 snd_seq_release+0x50/0xe0 sound/core/seq/seq_clientmgr.c:387 __fput+0x270/0xb80 fs/file_table.c:422 __fput_sync+0x47/0x50 fs/file_table.c:507 __do_sys_close fs/open.c:1556 [inline] __se_sys_close fs/open.c:1541 [inline] __x64_sys_close+0x86/0x100 fs/open.c:1541 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6d/0x75 INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 class_spinlock_irqsave_constructor include/linux/spinlock.h:574 [inline] snd_timer_notify+0x111/0x3e0 sound/core/timer.c:1040 snd_pcm_timer_notify sound/core/pcm_native.c:622 [inline] snd_pcm_post_stop+0x197/0x1f0 sound/core/pcm_native.c:1520 snd_pcm_action_single+0x10a/0x150 sound/core/pcm_native.c:1289 snd_pcm_action+0x70/0x90 sound/core/pcm_native.c:1370 snd_pcm_stop sound/core/pcm_native.c:1543 [inline] snd_pcm_drop+0x165/0x2b0 sound/core/pcm_native.c:2208 snd_pcm_kernel_ioctl+0x22d/0x2d0 sound/core/pcm_native.c:3444 snd_pcm_oss_sync+0x227/0x7f0 sound/core/oss/pcm_oss.c:1734 snd_pcm_oss_ioctl+0x1150/0x37a0 sound/core/oss/pcm_oss.c:2619 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:904 [inline] __se_sys_ioctl fs/ioctl.c:890 [inline] __x64_sys_ioctl+0x193/0x220 fs/ioctl.c:890 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6d/0x75 } ... key at: [] __key.6+0x0/0x40 ... acquired at: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 class_spinlock_irqsave_constructor include/linux/spinlock.h:574 [inline] snd_timer_notify+0x111/0x3e0 sound/core/timer.c:1040 snd_pcm_timer_notify sound/core/pcm_native.c:622 [inline] snd_pcm_post_stop+0x197/0x1f0 sound/core/pcm_native.c:1520 snd_pcm_action_single+0x10a/0x150 sound/core/pcm_native.c:1289 snd_pcm_action+0x70/0x90 sound/core/pcm_native.c:1370 snd_pcm_stop sound/core/pcm_native.c:1543 [inline] snd_pcm_drop+0x165/0x2b0 sound/core/pcm_native.c:2208 snd_pcm_kernel_ioctl+0x22d/0x2d0 sound/core/pcm_native.c:3444 snd_pcm_oss_sync+0x227/0x7f0 sound/core/oss/pcm_oss.c:1734 snd_pcm_oss_ioctl+0x1150/0x37a0 sound/core/oss/pcm_oss.c:2619 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:904 [inline] __se_sys_ioctl fs/ioctl.c:890 [inline] __x64_sys_ioctl+0x193/0x220 fs/ioctl.c:890 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6d/0x75 -> (&group->lock#2){..-.}-{2:2} { IN-SOFTIRQ-W at: lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 _snd_pcm_stream_lock_irqsave+0xa0/0xd0 sound/core/pcm_native.c:170 class_pcm_stream_lock_irqsave_constructor include/sound/pcm.h:669 [inline] snd_pcm_period_elapsed+0x20/0x50 sound/core/pcm_lib.c:1904 dummy_hrtimer_callback+0x9d/0x1c0 sound/drivers/dummy.c:385 __run_hrtimer kernel/time/hrtimer.c:1692 [inline] __hrtimer_run_queues+0x20c/0xc20 kernel/time/hrtimer.c:1756 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1773 __do_softirq+0x218/0x8de kernel/softirq.c:554 invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu kernel/softirq.c:633 [inline] irq_exit_rcu+0xb9/0x120 kernel/softirq.c:645 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0x95/0xb0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 __sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:527 on_stack arch/x86/include/asm/stacktrace.h:60 [inline] unwind_next_frame+0x11af/0x23a0 arch/x86/kernel/unwind_orc.c:665 arch_stack_walk+0x100/0x170 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579 poison_slab_object mm/kasan/common.c:240 [inline] __kasan_slab_free+0x11d/0x1a0 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] kfree+0x129/0x370 mm/slub.c:4390 tomoyo_path_perm+0x3dd/0x450 security/tomoyo/file.c:840 tomoyo_path_symlink+0x98/0xe0 security/tomoyo/tomoyo.c:212 security_path_symlink+0x108/0x170 security/security.c:1870 do_symlinkat+0x10e/0x310 fs/namei.c:4508 __do_sys_symlinkat fs/namei.c:4526 [inline] __se_sys_symlinkat fs/namei.c:4523 [inline] __x64_sys_symlinkat+0x97/0xc0 fs/namei.c:4523 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6d/0x75 INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719 __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] snd_pcm_group_lock_irq sound/core/pcm_native.c:97 [inline] snd_pcm_stream_lock_irq sound/core/pcm_native.c:136 [inline] class_pcm_stream_lock_irq_constructor include/sound/pcm.h:666 [inline] snd_pcm_hw_params+0x151/0x1a30 sound/core/pcm_native.c:740 snd_pcm_kernel_ioctl+0x147/0x2d0 sound/core/pcm_native.c:3434 snd_pcm_oss_change_params_locked+0x146c/0x3aa0 sound/core/oss/pcm_oss.c:965 snd_pcm_oss_change_params sound/core/oss/pcm_oss.c:1105 [inline] snd_pcm_oss_get_active_substream+0x168/0x1d0 sound/core/oss/pcm_oss.c:1122 snd_pcm_oss_get_rate sound/core/oss/pcm_oss.c:1778 [inline] snd_pcm_oss_set_rate sound/core/oss/pcm_oss.c:1770 [inline] snd_pcm_oss_ioctl+0x21e1/0x37a0 sound/core/oss/pcm_oss.c:2623 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:904 [inline] __se_sys_ioctl fs/ioctl.c:890 [inline] __x64_sys_ioctl+0x193/0x220 fs/ioctl.c:890 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6d/0x75 } ... key at: [] __key.5+0x0/0x40 ... acquired at: mark_usage kernel/locking/lockdep.c:4567 [inline] __lock_acquire+0x13d4/0x3b30 kernel/locking/lockdep.c:5091 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 _snd_pcm_stream_lock_irqsave+0xa0/0xd0 sound/core/pcm_native.c:170 class_pcm_stream_lock_irqsave_constructor include/sound/pcm.h:669 [inline] snd_pcm_period_elapsed+0x20/0x50 sound/core/pcm_lib.c:1904 dummy_hrtimer_callback+0x9d/0x1c0 sound/drivers/dummy.c:385 __run_hrtimer kernel/time/hrtimer.c:1692 [inline] __hrtimer_run_queues+0x20c/0xc20 kernel/time/hrtimer.c:1756 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1773 __do_softirq+0x218/0x8de kernel/softirq.c:554 invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu kernel/softirq.c:633 [inline] irq_exit_rcu+0xb9/0x120 kernel/softirq.c:645 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0x95/0xb0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 __sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:527 on_stack arch/x86/include/asm/stacktrace.h:60 [inline] unwind_next_frame+0x11af/0x23a0 arch/x86/kernel/unwind_orc.c:665 arch_stack_walk+0x100/0x170 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579 poison_slab_object mm/kasan/common.c:240 [inline] __kasan_slab_free+0x11d/0x1a0 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] kfree+0x129/0x370 mm/slub.c:4390 tomoyo_path_perm+0x3dd/0x450 security/tomoyo/file.c:840 tomoyo_path_symlink+0x98/0xe0 security/tomoyo/tomoyo.c:212 security_path_symlink+0x108/0x170 security/security.c:1870 do_symlinkat+0x10e/0x310 fs/namei.c:4508 __do_sys_symlinkat fs/namei.c:4526 [inline] __se_sys_symlinkat fs/namei.c:4523 [inline] __x64_sys_symlinkat+0x97/0xc0 fs/namei.c:4523 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6d/0x75 stack backtrace: CPU: 1 PID: 8090 Comm: syz-executor.3 Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #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+0x116/0x1f0 lib/dump_stack.c:114 print_irq_inversion_bug.part.0+0x3e9/0x5a0 kernel/locking/lockdep.c:4080 print_irq_inversion_bug kernel/locking/lockdep.c:4033 [inline] check_usage_forwards kernel/locking/lockdep.c:4111 [inline] mark_lock_irq kernel/locking/lockdep.c:4243 [inline] mark_lock+0x574/0xc60 kernel/locking/lockdep.c:4678 mark_usage kernel/locking/lockdep.c:4567 [inline] __lock_acquire+0x13d4/0x3b30 kernel/locking/lockdep.c:5091 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 _snd_pcm_stream_lock_irqsave+0xa0/0xd0 sound/core/pcm_native.c:170 class_pcm_stream_lock_irqsave_constructor include/sound/pcm.h:669 [inline] snd_pcm_period_elapsed+0x20/0x50 sound/core/pcm_lib.c:1904 dummy_hrtimer_callback+0x9d/0x1c0 sound/drivers/dummy.c:385 __run_hrtimer kernel/time/hrtimer.c:1692 [inline] __hrtimer_run_queues+0x20c/0xc20 kernel/time/hrtimer.c:1756 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1773 __do_softirq+0x218/0x8de kernel/softirq.c:554 invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu kernel/softirq.c:633 [inline] irq_exit_rcu+0xb9/0x120 kernel/softirq.c:645 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0x95/0xb0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:200 Code: be b0 01 00 00 e8 a0 ff ff ff 31 c0 c3 cc cc cc cc 66 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 65 48 8b 15 04 db 76 7e 65 8b 05 05 db 76 7e a9 00 01 RSP: 0018:ffffc9000424f6c8 EFLAGS: 00000287 RAX: dffffc0000000000 RBX: ffffc9000424f750 RCX: ffffffff813ca7f6 RDX: 1ffff92000849eec RSI: ffffffff813ca852 RDI: ffffc9000424f760 RBP: ffffc9000424fe50 R08: 0000000000000004 R09: 0000000000000001 R10: 0000000000000001 R11: 0000000000000003 R12: ffffc90004248000 R13: ffffc90004250000 R14: 0000000000000001 R15: 0000000000000001 on_stack arch/x86/include/asm/stacktrace.h:60 [inline] unwind_next_frame+0x11af/0x23a0 arch/x86/kernel/unwind_orc.c:665 arch_stack_walk+0x100/0x170 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579 poison_slab_object mm/kasan/common.c:240 [inline] __kasan_slab_free+0x11d/0x1a0 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] kfree+0x129/0x370 mm/slub.c:4390 tomoyo_path_perm+0x3dd/0x450 security/tomoyo/file.c:840 tomoyo_path_symlink+0x98/0xe0 security/tomoyo/tomoyo.c:212 security_path_symlink+0x108/0x170 security/security.c:1870 do_symlinkat+0x10e/0x310 fs/namei.c:4508 __do_sys_symlinkat fs/namei.c:4526 [inline] __se_sys_symlinkat fs/namei.c:4523 [inline] __x64_sys_symlinkat+0x97/0xc0 fs/namei.c:4523 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6d/0x75 RIP: 0033:0x7fa5a827d5e7 Code: 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 0a 01 00 00 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:00007fff2d0a2d08 EFLAGS: 00000206 ORIG_RAX: 000000000000010a RAX: ffffffffffffffda RBX: 00007fff2d0a2dd0 RCX: 00007fa5a827d5e7 RDX: 00007fa5a82ca51b RSI: 00000000ffffff9c RDI: 00007fa5a82c950e RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000001 ---------------- Code disassembly (best guess): 0: be b0 01 00 00 mov $0x1b0,%esi 5: e8 a0 ff ff ff call 0xffffffaa a: 31 c0 xor %eax,%eax c: c3 ret d: cc int3 e: cc int3 f: cc int3 10: cc int3 11: 66 0f 1f 84 00 00 00 nopw 0x0(%rax,%rax,1) 18: 00 00 1a: 90 nop 1b: 90 nop 1c: 90 nop 1d: 90 nop 1e: 90 nop 1f: 90 nop 20: 90 nop 21: 90 nop 22: 90 nop 23: 90 nop 24: 90 nop 25: 90 nop 26: 90 nop 27: 90 nop 28: 90 nop 29: 90 nop * 2a: f3 0f 1e fa endbr64 <-- trapping instruction 2e: 65 48 8b 15 04 db 76 mov %gs:0x7e76db04(%rip),%rdx # 0x7e76db3a 35: 7e 36: 65 8b 05 05 db 76 7e mov %gs:0x7e76db05(%rip),%eax # 0x7e76db42 3d: a9 .byte 0xa9 3e: 00 01 add %al,(%rcx)