================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6fa/0x960 kernel/bpf/stackmap.c:274 Write of size 32 at addr ffff888131c54290 by task syz.2.724/2727 CPU: 0 PID: 2727 Comm: syz.2.724 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Call Trace: __dump_stack+0x21/0x24 lib/dump_stack.c:88 dump_stack_lvl+0x110/0x170 lib/dump_stack.c:106 print_address_description+0x71/0x200 mm/kasan/report.c:316 print_report+0x4a/0x60 mm/kasan/report.c:420 kasan_report+0x122/0x150 mm/kasan/report.c:524 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x249/0x2a0 mm/kasan/generic.c:189 memcpy+0x44/0x70 mm/kasan/shadow.c:66 __bpf_get_stackid+0x6fa/0x960 kernel/bpf/stackmap.c:274 ____bpf_get_stackid_pe kernel/bpf/stackmap.c:365 [inline] bpf_get_stackid_pe+0x2ee/0x400 kernel/bpf/stackmap.c:334 bpf_prog_7073f9780ce25fb5+0x21/0x39 bpf_dispatcher_nop_func include/linux/bpf.h:987 [inline] __bpf_prog_run include/linux/filter.h:607 [inline] bpf_prog_run include/linux/filter.h:614 [inline] bpf_overflow_handler+0x3d0/0x5e0 kernel/events/core.c:10238 __perf_event_overflow+0x437/0x620 kernel/events/core.c:9448 perf_swevent_hrtimer+0x400/0x5b0 kernel/events/core.c:10879 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x3bb/0x8e0 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x3c7/0x8c0 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline] __sysvec_apic_timer_interrupt+0x11e/0x440 arch/x86/kernel/apic/apic.c:1124 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1118 asm_sysvec_apic_timer_interrupt+0x1b/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:should_fail_ex+0x41/0x520 lib/fault-inject.c:119 Code: 49 89 fe 48 ba 00 00 00 00 00 fc ff df 65 8b 05 2d 32 76 7d a9 00 01 ff 00 0f 84 fa 00 00 00 4c 89 f3 48 c1 eb 03 80 3c 13 00 <74> 0e 4c 89 f7 49 89 d4 e8 b2 8f 2a ff 4c 89 e2 49 83 3e 00 0f 84 RSP: 0018:ffffc90001d3f9f8 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 1ffffffff0e39c08 RCX: ffff88812103e540 RDX: dffffc0000000000 RSI: 0000000000000001 RDI: ffffffff871ce040 RBP: ffffc90001d3fa40 R08: ffffc90001d3fbf7 R09: ffffc90001d3fbe0 R10: dffffc0000000000 R11: fffff520003a7f7f R12: ffff88812103f04c R13: 0000000000000000 R14: ffffffff871ce040 R15: 0000000000000001 should_fail+0xb/0x10 lib/fault-inject.c:157 should_fail_futex kernel/futex/core.c:83 [inline] get_futex_key+0x143/0xb10 kernel/futex/core.c:241 futex_wake+0x150/0x8e0 kernel/futex/waitwake.c:156 do_futex+0x2bf/0x430 kernel/futex/syscalls.c:141 __do_sys_futex kernel/futex/syscalls.c:213 [inline] __se_sys_futex+0x136/0x310 kernel/futex/syscalls.c:194 __x64_sys_futex+0xe5/0x100 kernel/futex/syscalls.c:194 x64_sys_call+0x7ec/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:203 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f2ac2b9c819 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:00007f2ac3a550e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 00007f2ac2e15fa8 RCX: 00007f2ac2b9c819 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f2ac2e15fac RBP: 00007f2ac2e15fa0 R08: 002b047376ddeccc R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f2ac2e16038 R14: 00007ffe58d3f020 R15: 00007ffe58d3f108 Allocated by task 2727: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 kasan_save_alloc_info+0x25/0x30 mm/kasan/generic.c:505 ____kasan_kmalloc mm/kasan/common.c:380 [inline] __kasan_kmalloc+0x95/0xb0 mm/kasan/common.c:389 kasan_kmalloc include/linux/kasan.h:212 [inline] __do_kmalloc_node mm/slab_common.c:938 [inline] __kmalloc_node+0xb2/0x1e0 mm/slab_common.c:945 kmalloc_node include/linux/slab.h:589 [inline] __bpf_map_area_alloc kernel/bpf/syscall.c:328 [inline] bpf_map_area_alloc+0x4b/0xe0 kernel/bpf/syscall.c:341 prealloc_elems_and_freelist+0x8a/0x1e0 kernel/bpf/stackmap.c:51 stack_map_alloc+0x3a7/0x530 kernel/bpf/stackmap.c:117 find_and_alloc_map kernel/bpf/syscall.c:133 [inline] map_create+0x49c/0xd80 kernel/bpf/syscall.c:1126 __sys_bpf+0x34e/0x850 kernel/bpf/syscall.c:4987 __do_sys_bpf kernel/bpf/syscall.c:5109 [inline] __se_sys_bpf kernel/bpf/syscall.c:5107 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5107 x64_sys_call+0x488/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:322 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff888131c54280 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 16 bytes inside of 32-byte region [ffff888131c54280, ffff888131c542a0) The buggy address belongs to the physical page: page:ffffea0004c71500 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x131c54 flags: 0x4000000000000200(slab|zone=1) raw: 4000000000000200 ffffea00047ede00 dead000000000003 ffff888100042600 raw: 0000000000000000 0000000080400040 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x12a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY), pid 6, tgid 6 (kworker/0:0), ts 24187725704, free_ts 0 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f5/0x210 mm/page_alloc.c:2670 prep_new_page+0x1c/0x110 mm/page_alloc.c:2677 get_page_from_freelist+0x2d12/0x2d80 mm/page_alloc.c:4583 __alloc_pages+0x1fa/0x610 mm/page_alloc.c:5924 alloc_slab_page+0x6e/0xf0 include/linux/gfp.h:-1 allocate_slab mm/slub.c:1967 [inline] new_slab+0x98/0x3d0 mm/slub.c:2020 ___slab_alloc+0x6bd/0xb20 mm/slub.c:3177 __slab_alloc+0x5e/0xa0 mm/slub.c:3263 slab_alloc_node mm/slub.c:3348 [inline] __kmem_cache_alloc_node+0x203/0x2c0 mm/slub.c:3423 kmalloc_trace+0x29/0xb0 mm/slab_common.c:1028 kmalloc include/linux/slab.h:563 [inline] kzalloc include/linux/slab.h:699 [inline] ref_tracker_alloc+0x169/0x4a0 lib/ref_tracker.c:85 __netdev_tracker_alloc include/linux/netdevice.h:4085 [inline] netdev_hold include/linux/netdevice.h:4114 [inline] ___neigh_create+0xbab/0x1e20 net/core/neighbour.c:657 __neigh_create+0x31/0x40 net/core/neighbour.c:737 ip6_finish_output2+0xa56/0x18a0 net/ipv6/ip6_output.c:129 __ip6_finish_output net/ipv6/ip6_output.c:205 [inline] ip6_finish_output+0x5f9/0xbb0 net/ipv6/ip6_output.c:216 NF_HOOK_COND include/linux/netfilter.h:294 [inline] ip6_output+0x1fa/0x410 net/ipv6/ip6_output.c:237 page_owner free stack trace missing Memory state around the buggy address: ffff888131c54180: 00 00 00 fc fc fc fc fc 00 00 00 00 fc fc fc fc ffff888131c54200: 00 00 01 fc fc fc fc fc 00 00 00 00 fc fc fc fc >ffff888131c54280: 00 00 00 fc fc fc fc fc 00 00 00 00 fc fc fc fc ^ ffff888131c54300: fa fb fb fb fc fc fc fc 00 00 00 00 fc fc fc fc ffff888131c54380: 00 00 04 fc fc fc fc fc 00 00 00 00 fc fc fc fc ================================================================== ---------------- Code disassembly (best guess): 0: 49 89 fe mov %rdi,%r14 3: 48 ba 00 00 00 00 00 movabs $0xdffffc0000000000,%rdx a: fc ff df d: 65 8b 05 2d 32 76 7d mov %gs:0x7d76322d(%rip),%eax # 0x7d763241 14: a9 00 01 ff 00 test $0xff0100,%eax 19: 0f 84 fa 00 00 00 je 0x119 1f: 4c 89 f3 mov %r14,%rbx 22: 48 c1 eb 03 shr $0x3,%rbx 26: 80 3c 13 00 cmpb $0x0,(%rbx,%rdx,1) * 2a: 74 0e je 0x3a <-- trapping instruction 2c: 4c 89 f7 mov %r14,%rdi 2f: 49 89 d4 mov %rdx,%r12 32: e8 b2 8f 2a ff call 0xff2a8fe9 37: 4c 89 e2 mov %r12,%rdx 3a: 49 83 3e 00 cmpq $0x0,(%r14) 3e: 0f .byte 0xf 3f: 84 .byte 0x84