================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6bf/0x900 kernel/bpf/stackmap.c:271 Write of size 32 at addr ffff88802412bb90 by task syz.5.91/6367 CPU: 1 PID: 6367 Comm: syz.5.91 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xa8/0x210 mm/kasan/report.c:468 kasan_report+0x117/0x150 mm/kasan/report.c:581 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x241/0x290 mm/kasan/generic.c:187 __asan_memcpy+0x40/0x70 mm/kasan/shadow.c:106 __bpf_get_stackid+0x6bf/0x900 kernel/bpf/stackmap.c:271 ____bpf_get_stackid_pe kernel/bpf/stackmap.c:362 [inline] bpf_get_stackid_pe+0x343/0x410 kernel/bpf/stackmap.c:331 bpf_prog_329ce602f177131b+0x29/0x3e bpf_dispatcher_nop_func include/linux/bpf.h:1224 [inline] __bpf_prog_run include/linux/filter.h:616 [inline] bpf_prog_run include/linux/filter.h:623 [inline] bpf_overflow_handler+0x1fc/0x510 kernel/events/core.c:10584 __perf_event_overflow+0x447/0x630 kernel/events/core.c:9720 perf_event_overflow kernel/events/core.c:9741 [inline] perf_swevent_hrtimer+0x439/0x610 kernel/events/core.c:11230 __run_hrtimer kernel/time/hrtimer.c:1750 [inline] __hrtimer_run_queues+0x4e1/0xc40 kernel/time/hrtimer.c:1814 hrtimer_interrupt+0x3c9/0x9c0 kernel/time/hrtimer.c:1876 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1077 [inline] __sysvec_apic_timer_interrupt+0xfb/0x3b0 arch/x86/kernel/apic/apic.c:1094 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0x51/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:___slab_alloc+0x111a/0x12f0 mm/slub.c:3318 Code: c7 44 24 68 00 00 00 00 9c 8f 44 24 68 f7 44 24 68 00 02 00 00 75 7a 41 f7 c6 00 02 00 00 74 01 fb 65 48 8b 04 25 28 00 00 00 <48> 3b 44 24 70 0f 85 ef 00 00 00 4c 89 e8 48 83 c4 78 5b 41 5c 41 RSP: 0018:ffffc900001f05d8 EFLAGS: 00000206 RAX: 53861a235e368600 RBX: ffff8880b8f44180 RCX: 53861a235e368600 RDX: dffffc0000000000 RSI: ffffffff8acac9e0 RDI: ffffffff8b1c8e60 RBP: ffffffff81debf2f R08: ffffffff911c55c7 R09: 1ffffffff2238ab8 R10: dffffc0000000000 R11: fffffbfff2238ab9 R12: 0000000000000001 R13: ffff88807b9a7140 R14: 0000000000000246 R15: 0000000000000001 __slab_alloc mm/slub.c:3339 [inline] __slab_alloc_node mm/slub.c:3392 [inline] slab_alloc_node mm/slub.c:3485 [inline] slab_alloc mm/slub.c:3503 [inline] __kmem_cache_alloc_lru mm/slub.c:3510 [inline] kmem_cache_alloc+0x1b3/0x2d0 mm/slub.c:3519 skb_clone+0x1eb/0x370 net/core/skbuff.c:1915 dev_queue_xmit_nit+0x24d/0xbb0 net/core/dev.c:2353 xmit_one net/core/dev.c:3640 [inline] dev_hard_start_xmit+0x148/0x740 net/core/dev.c:3660 __dev_queue_xmit+0x19a3/0x3660 net/core/dev.c:4454 lapb_data_transmit+0x8a/0xa0 net/lapb/lapb_iface.c:447 lapb_transmit_buffer+0x163/0x200 net/lapb/lapb_out.c:149 lapb_t1timer_expiry+0x699/0xab0 net/lapb/lapb_timer.c:-1 call_timer_fn+0x189/0x540 kernel/time/timer.c:1701 expire_timers kernel/time/timer.c:1752 [inline] __run_timers+0x542/0x800 kernel/time/timer.c:2023 run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2036 handle_softirqs+0x280/0x820 kernel/softirq.c:578 __do_softirq kernel/softirq.c:612 [inline] invoke_softirq kernel/softirq.c:452 [inline] __irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:preempt_schedule_irq+0xba/0x150 kernel/sched/core.c:7010 Code: 00 00 43 c6 44 37 04 f8 74 0b 0f 0b 48 f7 03 08 00 00 00 74 6f bf 01 00 00 00 e8 51 f6 cd f6 e8 7c 03 ff f6 fb bf 01 00 00 00 f1 b4 ff ff 43 c6 44 37 08 00 48 c7 44 24 40 00 00 00 00 9c 8f RSP: 0018:ffffc90004c8fba0 EFLAGS: 00000286 RAX: 53861a235e368600 RBX: 0000000000000000 RCX: 53861a235e368600 RDX: dffffc0000000000 RSI: ffffffff8acac9e0 RDI: 0000000000000001 RBP: ffffc90004c8fc40 R08: ffffffff8e8b15ef R09: 1ffffffff1d162bd R10: dffffc0000000000 R11: fffffbfff1d162be R12: 0000000000000000 R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff92000991f74 irqentry_exit+0x67/0x70 kernel/entry/common.c:438 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:sched_mm_cid_remote_clear_old kernel/sched/core.c:11919 [inline] RIP: 0010:task_mm_cid_work+0x2b2/0x770 kernel/sched/core.c:11997 Code: 07 0f 87 17 03 00 00 44 89 e0 83 e0 07 48 8d 1c c5 30 7a a7 8c 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 <74> 08 48 89 df e8 e4 eb 80 00 4c 8b 33 49 8d 9e 50 ca 03 00 48 89 RSP: 0018:ffffc90004c8fd00 EFLAGS: 00000246 RAX: 1ffffffff194ef46 RBX: ffffffff8ca77a30 RCX: dffffc0000000000 RDX: 0000000000000003 RSI: 0000000000000008 RDI: ffffc90004c8fd80 RBP: ffffc90004c8fdf0 R08: ffffc90004c8fd87 R09: 1ffff92000991fb0 R10: dffffc0000000000 R11: fffff52000991fb1 R12: 0000000000000000 R13: ffff88801bba00d0 R14: ffffc90004c8fd80 R15: 00000000ffffcb49 task_work_run+0x1d4/0x260 kernel/task_work.c:245 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xa0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fec6239cdd9 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:00007fec632150e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 0000000000000000 RBX: 00007fec62615fa8 RCX: 00007fec6239cdd9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fec62615fa8 RBP: 00007fec62615fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fec62616038 R14: 00007fff88ffcb10 R15: 00007fff88ffcbf8 Allocated by task 6367: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 ____kasan_kmalloc mm/kasan/common.c:375 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:384 kasan_kmalloc include/linux/kasan.h:198 [inline] __do_kmalloc_node mm/slab_common.c:1007 [inline] __kmalloc_node+0xb4/0x230 mm/slab_common.c:1014 kmalloc_node include/linux/slab.h:620 [inline] __bpf_map_area_alloc kernel/bpf/syscall.c:303 [inline] bpf_map_area_alloc+0x5e/0x110 kernel/bpf/syscall.c:316 prealloc_elems_and_freelist+0x86/0x1c0 kernel/bpf/stackmap.c:51 stack_map_alloc+0x33a/0x4c0 kernel/bpf/stackmap.c:114 map_create+0x877/0x12f0 kernel/bpf/syscall.c:1247 __sys_bpf+0x651/0x890 kernel/bpf/syscall.c:5459 __do_sys_bpf kernel/bpf/syscall.c:5581 [inline] __se_sys_bpf kernel/bpf/syscall.c:5579 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5579 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:46 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 __call_rcu_common kernel/rcu/tree.c:2721 [inline] call_rcu+0x153/0x950 kernel/rcu/tree.c:2837 nf_unregister_net_hook net/netfilter/core.c:-1 [inline] nf_unregister_net_hooks+0xcb/0x130 net/netfilter/core.c:613 ops_pre_exit_list net/core/net_namespace.c:163 [inline] cleanup_net+0x595/0xbb0 net/core/net_namespace.c:632 process_one_work kernel/workqueue.c:2653 [inline] process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2730 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2811 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 The buggy address belongs to the object at ffff88802412bb80 which belongs to the cache kmalloc-cg-64 of size 64 The buggy address is located 16 bytes inside of allocated 40-byte region [ffff88802412bb80, ffff88802412bba8) The buggy address belongs to the physical page: page:ffffea0000904ac0 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88802412b500 pfn:0x2412b memcg:ffff8880788bcc01 flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff888017c4da00 ffffea00018daac0 0000000000000004 raw: ffff88802412b500 000000008020001f 00000001ffffffff ffff8880788bcc01 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 5876, tgid 5876 (syz-executor), ts 108644709877, free_ts 108637861265 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1c1/0x200 mm/page_alloc.c:1581 prep_new_page mm/page_alloc.c:1588 [inline] get_page_from_freelist+0x1951/0x19e0 mm/page_alloc.c:3220 __alloc_pages+0x1f0/0x460 mm/page_alloc.c:4500 alloc_slab_page+0x5d/0x160 mm/slub.c:1881 allocate_slab mm/slub.c:2028 [inline] new_slab+0x87/0x2d0 mm/slub.c:2081 ___slab_alloc+0xc5d/0x12f0 mm/slub.c:3253 __slab_alloc mm/slub.c:3339 [inline] __slab_alloc_node mm/slub.c:3392 [inline] slab_alloc_node mm/slub.c:3485 [inline] __kmem_cache_alloc_node+0x19e/0x250 mm/slub.c:3534 kmalloc_trace+0x2a/0xe0 mm/slab_common.c:1098 kmalloc include/linux/slab.h:600 [inline] alloc_fdtable+0xca/0x2c0 fs/file.c:147 expand_fdtable fs/file.c:191 [inline] expand_files+0x40f/0x820 fs/file.c:249 ksys_dup3+0x107/0x330 fs/file.c:1228 __do_sys_dup2 fs/file.c:1263 [inline] __se_sys_dup2+0x2f/0x130 fs/file.c:1251 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1181 [inline] free_unref_page_prepare+0x7b2/0x8c0 mm/page_alloc.c:2365 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2458 __slab_free+0x35a/0x400 mm/slub.c:3736 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x75/0xd0 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:306 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6e/0x4b0 mm/slab.h:767 slab_alloc_node mm/slub.c:3495 [inline] slab_alloc mm/slub.c:3503 [inline] __kmem_cache_alloc_lru mm/slub.c:3510 [inline] kmem_cache_alloc+0x11a/0x2d0 mm/slub.c:3519 vm_area_dup+0x27/0x270 kernel/fork.c:501 __split_vma+0x1b4/0xc60 mm/mmap.c:2373 do_vmi_align_munmap+0x32a/0x16d0 mm/mmap.c:2501 do_vmi_munmap+0x252/0x2d0 mm/mmap.c:2660 __mmap_region mm/mmap.c:2710 [inline] mmap_region+0x773/0x2000 mm/mmap.c:2941 do_mmap+0x92c/0x10a0 mm/mmap.c:1385 vm_mmap_pgoff+0x1c4/0x3f0 mm/util.c:556 ksys_mmap_pgoff+0x520/0x700 mm/mmap.c:1431 Memory state around the buggy address: ffff88802412ba80: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc ffff88802412bb00: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc >ffff88802412bb80: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc ^ ffff88802412bc00: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88802412bc80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ================================================================== ---------------- Code disassembly (best guess): 0: c7 44 24 68 00 00 00 movl $0x0,0x68(%rsp) 7: 00 8: 9c pushf 9: 8f 44 24 68 pop 0x68(%rsp) d: f7 44 24 68 00 02 00 testl $0x200,0x68(%rsp) 14: 00 15: 75 7a jne 0x91 17: 41 f7 c6 00 02 00 00 test $0x200,%r14d 1e: 74 01 je 0x21 20: fb sti 21: 65 48 8b 04 25 28 00 mov %gs:0x28,%rax 28: 00 00 * 2a: 48 3b 44 24 70 cmp 0x70(%rsp),%rax <-- trapping instruction 2f: 0f 85 ef 00 00 00 jne 0x124 35: 4c 89 e8 mov %r13,%rax 38: 48 83 c4 78 add $0x78,%rsp 3c: 5b pop %rbx 3d: 41 5c pop %r12 3f: 41 rex.B