------------[ cut here ]------------ WARNING: CPU: 1 PID: 7560 at mm/maccess.c:226 copy_from_user_nofault+0x160/0x1c0 mm/maccess.c:226 Modules linked in: CPU: 1 PID: 7560 Comm: syz.5.1324 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 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:ffffc90000dd09f8 EFLAGS: 00010246 RAX: ffffffff819ed760 RBX: 0000000000000000 RCX: ffff888076f5bb80 RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: dffffc0000000000 R09: ffffed100edeb771 R10: ffffed100edeb771 R11: 1ffff1100edeb770 R12: ffff888076f5d308 R13: 00007ffffffff000 R14: ffffc90000dd0a68 R15: 0000000000000000 FS: 00007f80ac79f6c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2d820ff8 CR3: 0000000030874000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: 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_3d2613b5dfc7747f+0x32/0xdb0 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 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 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xa5/0x100 kernel/locking/spinlock.c:194 Code: 74 05 e8 5e 8d cb f7 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 c6 15 9f f7 65 8b 05 a7 13 50 76 85 c0 74 3c 48 c7 04 24 0e 36 RSP: 0018:ffffc90002e7eda0 EFLAGS: 00000206 RAX: 14145191ba70e600 RBX: 0000000000000a06 RCX: 14145191ba70e600 RDX: dffffc0000000000 RSI: ffffffff8a0b1820 RDI: 0000000000000001 RBP: ffffc90002e7ee20 R08: dffffc0000000000 R09: fffffbfff1ff7832 R10: fffffbfff1ff7832 R11: 1ffffffff1ff7831 R12: dffffc0000000000 R13: ffff888030e328c0 R14: ffffffff962c73d8 R15: 1ffff920005cfdb4 __debug_check_no_obj_freed lib/debugobjects.c:982 [inline] debug_check_no_obj_freed+0x515/0x530 lib/debugobjects.c:1003 slab_free_hook mm/slub.c:1685 [inline] slab_free_freelist_hook+0x8b/0x170 mm/slub.c:1736 slab_free mm/slub.c:3504 [inline] kmem_cache_free+0x8f/0x210 mm/slub.c:3520 sctp_packet_pack net/sctp/output.c:512 [inline] sctp_packet_transmit+0x14c3/0x2920 net/sctp/output.c:620 sctp_packet_singleton+0x230/0x330 net/sctp/outqueue.c:780 sctp_outq_flush_ctrl net/sctp/outqueue.c:911 [inline] sctp_outq_flush+0x48f/0x30d0 net/sctp/outqueue.c:1209 sctp_cmd_interpreter net/sctp/sm_sideeffect.c:-1 [inline] sctp_side_effects net/sctp/sm_sideeffect.c:1199 [inline] sctp_do_sm+0x4e61/0x5500 net/sctp/sm_sideeffect.c:1170 sctp_primitive_ASSOCIATE+0x91/0xc0 net/sctp/primitive.c:73 sctp_sendmsg_to_asoc+0x1499/0x1d90 net/sctp/socket.c:1842 sctp_sendmsg+0x19ae/0x2950 net/sctp/socket.c:2032 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] ____sys_sendmsg+0x5a2/0x8c0 net/socket.c:2436 ___sys_sendmsg+0x1f0/0x260 net/socket.c:2490 __sys_sendmsg net/socket.c:2519 [inline] __do_sys_sendmsg net/socket.c:2528 [inline] __se_sys_sendmsg+0x190/0x250 net/socket.c:2526 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f80ae537c29 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f80ac79f038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f80ae77efa0 RCX: 00007f80ae537c29 RDX: 0000000000000000 RSI: 0000200000000080 RDI: 0000000000000003 RBP: 00007f80ae5bae41 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f80ae77f038 R14: 00007f80ae77efa0 R15: 00007ffc8b815258 ---------------- Code disassembly (best guess): 0: 74 05 je 0x7 2: e8 5e 8d cb f7 call 0xf7cb8d65 7: 48 c7 44 24 20 00 00 movq $0x0,0x20(%rsp) e: 00 00 10: 9c pushf 11: 8f 44 24 20 pop 0x20(%rsp) 15: f6 44 24 21 02 testb $0x2,0x21(%rsp) 1a: 75 4b jne 0x67 1c: f7 c3 00 02 00 00 test $0x200,%ebx 22: 74 01 je 0x25 24: fb sti 25: bf 01 00 00 00 mov $0x1,%edi * 2a: e8 c6 15 9f f7 call 0xf79f15f5 <-- trapping instruction 2f: 65 8b 05 a7 13 50 76 mov %gs:0x765013a7(%rip),%eax # 0x765013dd 36: 85 c0 test %eax,%eax 38: 74 3c je 0x76 3a: 48 rex.W 3b: c7 .byte 0xc7 3c: 04 24 add $0x24,%al 3e: 0e (bad) 3f: 36 ss