------------[ cut here ]------------
WARNING: CPU: 0 PID: 4246 at mm/maccess.c:226 copy_from_user_nofault+0x160/0x1c0 mm/maccess.c:226
Modules linked in:
CPU: 0 PID: 4246 Comm: kworker/0:4 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Workqueue: events iterate_cleanup_work
RIP: 0010:copy_from_user_nofault+0x160/0x1c0 mm/maccess.c:226
Code: 24 45 31 f6 31 ff 89 de e8 3d f7 d8 ff 85 db 48 c7 c0 f2 ff ff ff 49 0f 44 c6 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 c0 f3 d8 ff <0f> 0b e9 1c ff ff ff 44 89 e1 80 e1 07 80 c1 03 38 c1 0f 8c ea fe
RSP: 0018:ffffc900000079b8 EFLAGS: 00010246
RAX: ffffffff819ed760 RBX: 0000000000000008 RCX: ffff888060e7d940
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: dffffc0000000000 R09: ffffed100c1cfb29
R10: ffffed100c1cfb29 R11: 1ffff1100c1cfb28 R12: ffff888060e7f0c8
R13: 00007ffffffff000 R14: ffffc90000007a28 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000022d26000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 bpf_probe_read_user_common kernel/trace/bpf_trace.c:157 [inline]
 ____bpf_probe_read_compat kernel/trace/bpf_trace.c:281 [inline]
 bpf_probe_read_compat+0xdd/0x170 kernel/trace/bpf_trace.c:277
 bpf_prog_ea44d77e194c9431+0x35/0xa60
 bpf_dispatcher_nop_func include/linux/bpf.h:888 [inline]
 __bpf_prog_run include/linux/filter.h:628 [inline]
 bpf_prog_run include/linux/filter.h:635 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:1878 [inline]
 bpf_trace_run3+0x17e/0x320 kernel/trace/bpf_trace.c:1916
 __bpf_trace_kmem_cache_free+0x99/0xc0 include/trace/events/kmem.h:138
 __traceiter_kmem_cache_free+0x30/0x50 include/trace/events/kmem.h:138
 trace_kmem_cache_free include/trace/events/kmem.h:138 [inline]
 kmem_cache_free+0x1e7/0x210 mm/slub.c:3521
 rcu_do_batch kernel/rcu/tree.c:2523 [inline]
 rcu_core+0x962/0x15d0 kernel/rcu/tree.c:2763
 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
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x4/0x60 kernel/kcov.c:205
Code: 84 00 00 00 00 00 53 48 89 fb e8 17 00 00 00 48 8b 3d 00 c9 f1 0b 48 89 de 5b e9 47 9e 43 00 00 00 cc cc 00 00 cc 48 8b 04 24 <65> 48 8b 0d 94 a4 8a 7e 65 8b 15 95 a4 8a 7e 81 e2 00 01 ff 00 74
RSP: 0018:ffffc9000323fac0 EFLAGS: 00000202
RAX: ffffffff8816a04c RBX: ffff88802b03faa0 RCX: ffff888060e7d940
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 1ffff11005607f54 R08: dffffc0000000000 R09: fffffbfff1ff782b
R10: fffffbfff1ff782b R11: 1ffffffff1ff782a R12: dffffc0000000000
R13: 0000000000000001 R14: ffffc9000323fb60 R15: ffffffff8816a090
 get_next_corpse net/netfilter/nf_conntrack_core.c:2335 [inline]
 nf_ct_iterate_cleanup+0x37c/0x3c0 net/netfilter/nf_conntrack_core.c:2381
 nf_ct_iterate_cleanup_net+0x10f/0x180 net/netfilter/nf_conntrack_core.c:2465
 iterate_cleanup_work+0x66/0x120 net/netfilter/nf_nat_masquerade.c:83
 process_one_work+0x863/0x1000 kernel/workqueue.c:2310
 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
----------------
Code disassembly (best guess):
   0:	84 00                	test   %al,(%rax)
   2:	00 00                	add    %al,(%rax)
   4:	00 00                	add    %al,(%rax)
   6:	53                   	push   %rbx
   7:	48 89 fb             	mov    %rdi,%rbx
   a:	e8 17 00 00 00       	call   0x26
   f:	48 8b 3d 00 c9 f1 0b 	mov    0xbf1c900(%rip),%rdi        # 0xbf1c916
  16:	48 89 de             	mov    %rbx,%rsi
  19:	5b                   	pop    %rbx
  1a:	e9 47 9e 43 00       	jmp    0x439e66
  1f:	00 00                	add    %al,(%rax)
  21:	cc                   	int3
  22:	cc                   	int3
  23:	00 00                	add    %al,(%rax)
  25:	cc                   	int3
  26:	48 8b 04 24          	mov    (%rsp),%rax
* 2a:	65 48 8b 0d 94 a4 8a 	mov    %gs:0x7e8aa494(%rip),%rcx        # 0x7e8aa4c6 <-- trapping instruction
  31:	7e
  32:	65 8b 15 95 a4 8a 7e 	mov    %gs:0x7e8aa495(%rip),%edx        # 0x7e8aa4ce
  39:	81 e2 00 01 ff 00    	and    $0xff0100,%edx
  3f:	74                   	.byte 0x74