general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 1 PID: 5597 Comm: syz.5.228 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:dequeue_head net/sched/sch_fq_codel.c:120 [inline]
RIP: 0010:fq_codel_drop net/sched/sch_fq_codel.c:168 [inline]
RIP: 0010:fq_codel_enqueue+0xd2d/0x1590 net/sched/sch_fq_codel.c:230
Code: 24 08 48 8b 44 24 20 80 3c 10 00 74 12 4c 89 ef e8 08 b2 be f9 48 ba 00 00 00 00 00 fc ff df 4d 8b 65 00 4c 89 e0 48 c1 e8 03 <80> 3c 10 00 74 12 4c 89 e7 e8 e5 b1 be f9 48 ba 00 00 00 00 00 fc
RSP: 0018:ffffc90000dd05e0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 1ffff920001ba108 RCX: 1ffff11003e95e5a
RDX: dffffc0000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000dd0738 R08: dffffc0000000000 R09: fffffbfff1ff5432
R10: fffffbfff1ff5432 R11: 1ffffffff1ff5431 R12: 0000000000000000
R13: ffff888055e20000 R14: 0000000000000000 R15: 0000000000000000
FS: 00007f4b4bce66c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c42b032 CR3: 0000000023b98000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
dev_qdisc_enqueue+0x48/0x210 net/core/dev.c:3852
__dev_xmit_skb net/core/dev.c:3936 [inline]
__dev_queue_xmit+0xd7e/0x2ed0 net/core/dev.c:4253
tipc_l2_send_msg+0x30a/0x3c0 net/tipc/bearer.c:518
tipc_bearer_xmit_skb+0x292/0x3c0 net/tipc/bearer.c:577
tipc_disc_timeout+0x568/0x6b0 net/tipc/discover.c:338
call_timer_fn+0x16c/0x530 kernel/time/timer.c:1451
expire_timers kernel/time/timer.c:1496 [inline]
__run_timers+0x525/0x7c0 kernel/time/timer.c:1767
run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1780
handle_softirqs+0x328/0x820 kernel/softirq.c:576
__do_softirq kernel/softirq.c:610 [inline]
invoke_softirq kernel/softirq.c:450 [inline]
__irq_exit_rcu+0x12f/0x220 kernel/softirq.c:659
irq_exit_rcu+0x5/0x20 kernel/softirq.c:671
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:unwind_next_frame+0x118d/0x1d90 arch/x86/kernel/unwind_orc.c:-1
Code: 00 00 49 bd 00 00 00 00 00 fc ff df 48 8b 44 24 48 42 0f b6 04 28 84 c0 0f 85 30 08 00 00 8b 44 24 7c 39 03 0f 85 ff 00 00 00 <48> 8b 44 24 40 42 80 3c 28 00 74 0a 48 8b 7c 24 38 e8 6d aa 87 00
RSP: 0018:ffffc90002f5e468 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffffc90002f5e528 RCX: 0000000000000001
RDX: ffffc90002f5e568 RSI: ffffc90002f5f530 RDI: ffffc90002f5f530
RBP: ffffc90002f5e570 R08: dffffc0000000000 R09: ffffc90002f5e578
R10: fffff520005ebcb1 R11: 1ffff920005ebcaf R12: 1ffffffff1be1a21
R13: dffffc0000000000 R14: ffffc90002f5e578 R15: ffffffff8df0d106
arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x98/0xe0 kernel/stacktrace.c:122
save_stack+0xf3/0x1e0 mm/page_owner.c:119
__set_page_owner+0x41/0x2d0 mm/page_owner.c:181
prep_new_page mm/page_alloc.c:2426 [inline]
get_page_from_freelist+0x1b77/0x1c60 mm/page_alloc.c:4192
__alloc_pages+0x1e1/0x470 mm/page_alloc.c:5487
alloc_pages_vma+0x393/0x7c0 mm/mempolicy.c:2146
shmem_alloc_page mm/shmem.c:1586 [inline]
shmem_alloc_and_acct_page+0x427/0xb70 mm/shmem.c:1611
shmem_getpage_gfp+0x14f4/0x2d40 mm/shmem.c:1906
shmem_getpage mm/shmem.c:151 [inline]
shmem_write_begin+0xcd/0x1a0 mm/shmem.c:2474
generic_perform_write+0x2aa/0x530 mm/filemap.c:3785
__generic_file_write_iter+0x25f/0x4e0 mm/filemap.c:3912
generic_file_write_iter+0xa6/0x1b0 mm/filemap.c:3944
__kernel_write+0x4f9/0x930 fs/read_write.c:539
__dump_emit+0x243/0x360 fs/coredump.c:943
dump_user_range+0x84/0x340 fs/coredump.c:1017
elf_core_dump+0x2ff7/0x3530 fs/binfmt_elf.c:2285
do_coredump+0x1419/0x2960 fs/coredump.c:894
get_signal+0x40a/0x12c0 kernel/signal.c:2886
arch_do_signal_or_restart+0xc1/0x1300 arch/x86/kernel/signal.c:867
handle_signal_work kernel/entry/common.c:154 [inline]
exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
irqentry_exit_to_user_mode+0x5/0x30 kernel/entry/common.c:320
exc_page_fault+0x88/0x100 arch/x86/mm/fault.c:1504
asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606
RIP: 0033:0x0
Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6.
RSP: 002b:0000200000000008 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007f4b4dcd5fa0 RCX: 00007f4b4da7f749
RDX: 0000200000000040 RSI: 0000200000000000 RDI: 0000000004004000
RBP: 00007f4b4db03f91 R08: 00002000000000c0 R09: 00002000000000c0
R10: 0000200000000080 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f4b4dcd6038 R14: 00007f4b4dcd5fa0 R15: 00007ffdf548eb98
Modules linked in:
---[ end trace 765dc7af4ef0e236 ]---
RIP: 0010:dequeue_head net/sched/sch_fq_codel.c:120 [inline]
RIP: 0010:fq_codel_drop net/sched/sch_fq_codel.c:168 [inline]
RIP: 0010:fq_codel_enqueue+0xd2d/0x1590 net/sched/sch_fq_codel.c:230
Code: 24 08 48 8b 44 24 20 80 3c 10 00 74 12 4c 89 ef e8 08 b2 be f9 48 ba 00 00 00 00 00 fc ff df 4d 8b 65 00 4c 89 e0 48 c1 e8 03 <80> 3c 10 00 74 12 4c 89 e7 e8 e5 b1 be f9 48 ba 00 00 00 00 00 fc
RSP: 0018:ffffc90000dd05e0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 1ffff920001ba108 RCX: 1ffff11003e95e5a
RDX: dffffc0000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000dd0738 R08: dffffc0000000000 R09: fffffbfff1ff5432
R10: fffffbfff1ff5432 R11: 1ffffffff1ff5431 R12: 0000000000000000
R13: ffff888055e20000 R14: 0000000000000000 R15: 0000000000000000
FS: 00007f4b4bce66c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c42b032 CR3: 0000000023b98000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: 24 08 and $0x8,%al
2: 48 8b 44 24 20 mov 0x20(%rsp),%rax
7: 80 3c 10 00 cmpb $0x0,(%rax,%rdx,1)
b: 74 12 je 0x1f
d: 4c 89 ef mov %r13,%rdi
10: e8 08 b2 be f9 call 0xf9beb21d
15: 48 ba 00 00 00 00 00 movabs $0xdffffc0000000000,%rdx
1c: fc ff df
1f: 4d 8b 65 00 mov 0x0(%r13),%r12
23: 4c 89 e0 mov %r12,%rax
26: 48 c1 e8 03 shr $0x3,%rax
* 2a: 80 3c 10 00 cmpb $0x0,(%rax,%rdx,1) <-- trapping instruction
2e: 74 12 je 0x42
30: 4c 89 e7 mov %r12,%rdi
33: e8 e5 b1 be f9 call 0xf9beb21d
38: 48 rex.W
39: ba 00 00 00 00 mov $0x0,%edx
3e: 00 fc add %bh,%ah