Oops: general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] CPU: 0 UID: 0 PID: 6022 Comm: syz.1.95 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:ffffc90003b26820 EFLAGS: 00010003 RAX: 0000000000000002 RBX: 0000000000000000 RCX: dffffc0000000000 RDX: 0000000000000003 RSI: 0000000000000000 RDI: ffff8880b8620c60 RBP: ffffc90003b26a08 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff52000764cb4 R12: ffff8880b863c658 R13: ffff888125a6b000 R14: 1ffff110170c7922 R15: 0000000000000014 FS: 00007f63576cd6c0(0000) GS:ffff888125a6b000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000003c2d4000 CR4: 00000000003526f0 Call Trace: preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7552 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline] irqentry_exit+0x14f/0x8c0 kernel/entry/common.c:167 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:lock_acquire+0x221/0x350 kernel/locking/lockdep.c:5874 Code: ff ff ff e8 b1 bd 9c 09 f7 44 24 08 00 02 00 00 0f 84 3a ff ff ff 65 48 8b 05 5b 18 1a 11 48 3b 44 24 58 75 33 fb 48 83 c4 60 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 80 85 a0 09 cc 48 8d 3d e8 62 31 RSP: 0018:ffffc90003b26b38 EFLAGS: 00000282 RAX: d61fdbbd20003a00 RBX: 0000000000000000 RCX: 0000000000000046 RDX: 0000000002f62cf4 RSI: ffffffff8dbdec30 RDI: ffffffff8bcc4d80 RBP: ffffffff81774806 R08: ffffffff81774806 R09: ffffffff8e3cb2a0 R10: dffffc0000000000 R11: ffffffff81b0ac80 R12: 0000000000000002 R13: ffffffff8e3cb2a0 R14: 0000000000000000 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:300 [inline] rcu_read_lock include/linux/rcupdate.h:840 [inline] class_rcu_constructor include/linux/rcupdate.h:1183 [inline] unwind_next_frame+0xc3/0x2550 arch/x86/kernel/unwind_orc.c:495 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 save_stack+0x122/0x230 mm/page_owner.c:165 __set_page_owner+0x8d/0x4c0 mm/page_owner.c:341 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1859 prep_new_page mm/page_alloc.c:1867 [inline] get_page_from_freelist+0x265c/0x26e0 mm/page_alloc.c:3946 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5304 alloc_pages_mpol+0xd1/0x380 mm/mempolicy.c:2490 folio_alloc_mpol_noprof+0x3b/0x1e0 mm/mempolicy.c:2509 vma_alloc_folio_noprof+0xe1/0x1e0 mm/mempolicy.c:2544 folio_prealloc mm/memory.c:-1 [inline] wp_page_copy mm/memory.c:3875 [inline] do_wp_page+0x1109/0x3d90 mm/memory.c:4336 handle_pte_fault mm/memory.c:6395 [inline] __handle_mm_fault mm/memory.c:6517 [inline] handle_mm_fault+0xafb/0x14d0 mm/memory.c:6686 do_user_addr_fault+0x75b/0x1340 arch/x86/mm/fault.c:1394 handle_page_fault arch/x86/mm/fault.c:1483 [inline] exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1536 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595 RIP: 0010:__put_user_nocheck_4+0x3/0x20 arch/x86/lib/putuser.S:104 Code: d9 0f 01 cb 89 01 31 c9 0f 01 ca c3 cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 01 cb <89> 01 31 c9 0f 01 ca e9 11 57 04 00 90 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc90003b278d8 EFLAGS: 00050202 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000200000034030 RDX: 0000000000000002 RSI: 0000000000000002 RDI: 00000000ffffffff RBP: ffffc90003b27a50 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: fffffbfff1f9e71f R12: 1ffff92000764f28 R13: 0000200000034000 R14: 0000000000000000 R15: 0000000000000002 ____sys_recvmsg+0x319/0x4f0 net/socket.c:2935 ___sys_recvmsg+0x215/0x5a0 net/socket.c:2964 do_recvmmsg+0x32b/0x7e0 net/socket.c:3059 __sys_recvmmsg net/socket.c:3133 [inline] __do_sys_recvmmsg net/socket.c:3156 [inline] __se_sys_recvmmsg net/socket.c:3149 [inline] __x64_sys_recvmmsg+0x198/0x250 net/socket.c:3149 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f635949ce59 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:00007f63576cd028 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007f6359716090 RCX: 00007f635949ce59 RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000005 RBP: 00007f6359532e6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f6359716128 R14: 00007f6359716090 R15: 00007ffffd979208 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:ffffc90003b26820 EFLAGS: 00010003 RAX: 0000000000000002 RBX: 0000000000000000 RCX: dffffc0000000000 RDX: 0000000000000003 RSI: 0000000000000000 RDI: ffff8880b8620c60 RBP: ffffc90003b26a08 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff52000764cb4 R12: ffff8880b863c658 R13: ffff888125a6b000 R14: 1ffff110170c7922 R15: 0000000000000014 FS: 00007f63576cd6c0(0000) GS:ffff888125a6b000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000003c2d4000 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