Oops: general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] CPU: 1 UID: 0 PID: 9911 Comm: syz.5.1649 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:task_cpu include/linux/sched.h:2268 [inline] RIP: 0010:is_task_rq_idle kernel/sched/core.c:6169 [inline] RIP: 0010:cookie_equals kernel/sched/core.c:6174 [inline] RIP: 0010:pick_next_task kernel/sched/core.c:6355 [inline] RIP: 0010:__schedule+0x4030/0x5550 kernel/sched/core.c:7143 Code: 24 80 00 00 00 e8 80 97 f2 f6 48 8b 84 24 80 00 00 00 48 8b 18 4c 8d 7b 14 4c 89 f8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <0f> b6 04 08 84 c0 0f 85 87 04 00 00 45 8b 3f 49 83 ff 08 0f 83 98 RSP: 0018:ffffc90003d774c0 EFLAGS: 00010003 RAX: 0000000000000002 RBX: 0000000000000000 RCX: dffffc0000000000 RDX: 0000000000000003 RSI: 0000000000000001 RDI: ffff8880b863c918 RBP: ffffc90003d776a8 R08: ffffffff8fcf38f7 R09: 1ffffffff1f9e71e R10: dffffc0000000000 R11: fffffbfff1f9e71f R12: ffff8880b873c658 R13: ffff888125b6b000 R14: 1ffff110170e7922 R15: 0000000000000014 FS: 00007f9f1a83d6c0(0000) GS:ffff888125b6b000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc708c2da08 CR3: 000000005b7b4000 CR4: 00000000003526f0 Call Trace: preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7409 preempt_schedule_thunk+0x16/0x40 arch/x86/entry/thunk.S:12 class_preempt_destructor include/linux/preempt.h:468 [inline] raw_spin_unlock_irq_wake include/linux/sched/wake_q.h:89 [inline] rt_mutex_slowlock_block+0x596/0x670 kernel/locking/rtmutex.c:1665 __rt_mutex_slowlock kernel/locking/rtmutex.c:1746 [inline] __rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1786 [inline] rt_mutex_slowlock+0x2dc/0x780 kernel/locking/rtmutex.c:1826 __rt_mutex_lock kernel/locking/rtmutex.c:1841 [inline] __mutex_lock_common kernel/locking/rtmutex_api.c:560 [inline] mutex_lock_nested+0x168/0x1d0 kernel/locking/rtmutex_api.c:578 packet_flush_mclist net/packet/af_packet.c:3773 [inline] packet_release+0x478/0xd60 net/packet/af_packet.c:3153 __sock_release+0xb9/0x250 net/socket.c:714 sock_close+0x1c/0x30 net/socket.c:1516 __fput+0x461/0xa70 fs/file_table.c:512 task_work_run+0x1d9/0x270 kernel/task_work.c:233 get_signal+0x11eb/0x1330 kernel/signal.c:2810 arch_do_signal_or_restart+0xbc/0x840 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline] exit_to_user_mode_loop+0x104/0x710 kernel/entry/common.c:101 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline] do_syscall_64+0x353/0x580 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f9f1c60ce59 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f9f1a83d028 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: 0000000000000000 RBX: 00007f9f1c886090 RCX: 00007f9f1c60ce59 RDX: 0000000000000001 RSI: 0000000000000107 RDI: 0000000000000003 RBP: 00007f9f1c6a2d6f R08: 0000000000000010 R09: 0000000000000000 R10: 0000200000000100 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f9f1c886128 R14: 00007f9f1c886090 R15: 00007ffca412d388 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:task_cpu include/linux/sched.h:2268 [inline] RIP: 0010:is_task_rq_idle kernel/sched/core.c:6169 [inline] RIP: 0010:cookie_equals kernel/sched/core.c:6174 [inline] RIP: 0010:pick_next_task kernel/sched/core.c:6355 [inline] RIP: 0010:__schedule+0x4030/0x5550 kernel/sched/core.c:7143 Code: 24 80 00 00 00 e8 80 97 f2 f6 48 8b 84 24 80 00 00 00 48 8b 18 4c 8d 7b 14 4c 89 f8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <0f> b6 04 08 84 c0 0f 85 87 04 00 00 45 8b 3f 49 83 ff 08 0f 83 98 RSP: 0018:ffffc90003d774c0 EFLAGS: 00010003 RAX: 0000000000000002 RBX: 0000000000000000 RCX: dffffc0000000000 RDX: 0000000000000003 RSI: 0000000000000001 RDI: ffff8880b863c918 RBP: ffffc90003d776a8 R08: ffffffff8fcf38f7 R09: 1ffffffff1f9e71e R10: dffffc0000000000 R11: fffffbfff1f9e71f R12: ffff8880b873c658 R13: ffff888125b6b000 R14: 1ffff110170e7922 R15: 0000000000000014 FS: 00007f9f1a83d6c0(0000) GS:ffff888125b6b000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc708c2da08 CR3: 000000005b7b4000 CR4: 00000000003526f0 ---------------- Code disassembly (best guess): 0: 24 80 and $0x80,%al 2: 00 00 add %al,(%rax) 4: 00 e8 add %ch,%al 6: 80 97 f2 f6 48 8b 84 adcb $0x84,-0x74b7090e(%rdi) d: 24 80 and $0x80,%al f: 00 00 add %al,(%rax) 11: 00 48 8b add %cl,-0x75(%rax) 14: 18 4c 8d 7b sbb %cl,0x7b(%rbp,%rcx,4) 18: 14 4c adc $0x4c,%al 1a: 89 f8 mov %edi,%eax 1c: 48 c1 e8 03 shr $0x3,%rax 20: 48 b9 00 00 00 00 00 movabs $0xdffffc0000000000,%rcx 27: fc ff df * 2a: 0f b6 04 08 movzbl (%rax,%rcx,1),%eax <-- trapping instruction 2e: 84 c0 test %al,%al 30: 0f 85 87 04 00 00 jne 0x4bd 36: 45 8b 3f mov (%r15),%r15d 39: 49 83 ff 08 cmp $0x8,%r15 3d: 0f .byte 0xf 3e: 83 .byte 0x83 3f: 98 cwtl