================================================================== BUG: KASAN: slab-out-of-bounds in stack_map_get_build_id_offset+0x988/0x9b0 kernel/bpf/stackmap.c:147 Write of size 4 at addr ffff88810e991b30 by task syz.3.339/1918 CPU: 1 PID: 1918 Comm: syz.3.339 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 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 __asan_report_store4_noabort+0x17/0x20 mm/kasan/report_generic.c:355 stack_map_get_build_id_offset+0x988/0x9b0 kernel/bpf/stackmap.c:147 __bpf_get_stackid+0x5ac/0x960 kernel/bpf/stackmap.c:250 ____bpf_get_stackid_pe kernel/bpf/stackmap.c:365 [inline] bpf_get_stackid_pe+0x2ee/0x400 kernel/bpf/stackmap.c:334 bpf_prog_2414a5d5030ea31b+0x21/0x25 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+0x3c7/0x5e0 kernel/events/core.c:10273 __perf_event_overflow+0x458/0x640 kernel/events/core.c:9448 perf_swevent_overflow kernel/events/core.c:9531 [inline] perf_swevent_event+0x243/0x440 kernel/events/core.c:9582 do_perf_sw_event kernel/events/core.c:9695 [inline] ___perf_sw_event+0x3bf/0x500 kernel/events/core.c:9726 __perf_sw_event+0x134/0x270 kernel/events/core.c:9738 perf_sw_event include/linux/perf_event.h:1250 [inline] do_user_addr_fault+0xfe9/0x1030 arch/x86/mm/fault.c:1285 handle_page_fault arch/x86/mm/fault.c:1464 [inline] exc_page_fault+0x51/0xb0 arch/x86/mm/fault.c:1517 asm_exc_page_fault+0x27/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0010:copy_user_enhanced_fast_string+0xa/0x40 arch/x86/lib/copy_user_64.S:166 Code: ff c9 75 f2 89 d1 c1 e9 03 83 e2 07 f3 48 a5 89 d1 f3 a4 31 c0 0f 01 ca c3 8d 0c ca 89 ca eb 20 0f 01 cb 83 fa 40 72 38 89 d1 a4 31 c0 0f 01 ca c3 89 ca eb 0a 90 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc90000aa7a28 EFLAGS: 00050206 RAX: ffffffff82692c01 RBX: 000000000000004c RCX: 000000000000004c RDX: 000000000000004c RSI: 0000000500000200 RDI: ffffc90000aa7ac0 RBP: ffffc90000aa7a50 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff52000154f61 R12: 00007fffffffefb4 R13: 1ffff92000154f54 R14: ffffc90000aa7ac0 R15: 0000000500000200 copy_from_user include/linux/uaccess.h:161 [inline] vti6_siocdevprivate+0x3a4/0xe20 net/ipv6/ip6_vti.c:840 dev_siocdevprivate net/core/dev_ioctl.c:287 [inline] dev_ifsioc+0xa8b/0xd90 net/core/dev_ioctl.c:392 dev_ioctl+0x5d9/0xcf0 net/core/dev_ioctl.c:597 sock_ioctl+0x673/0x700 net/socket.c:1236 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0x12f/0x1b0 fs/ioctl.c:856 __x64_sys_ioctl+0x7b/0x90 fs/ioctl.c:856 x64_sys_call+0x58b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:17 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: 0033:0x7f65c439e159 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:00007f65c534f028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f65c4625fa0 RCX: 00007f65c439e159 RDX: 0000200000000080 RSI: 00000000000089f1 RDI: 0000000000000009 RBP: 00007f65c443503b R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f65c4626038 R14: 00007f65c4625fa0 R15: 00007fff1b909e68 Allocated by task 1918: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 kasan_save_alloc_info+0x1f/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+0x398/0x520 kernel/bpf/stackmap.c:117 find_and_alloc_map kernel/bpf/syscall.c:133 [inline] map_create+0x467/0xcf0 kernel/bpf/syscall.c:1126 __sys_bpf+0x34e/0x850 kernel/bpf/syscall.c:4988 __do_sys_bpf kernel/bpf/syscall.c:5110 [inline] __se_sys_bpf kernel/bpf/syscall.c:5108 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5108 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 Last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:46 __kasan_record_aux_stack+0xb6/0xc0 mm/kasan/generic.c:486 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:496 kvfree_call_rcu+0x8b/0x7a0 kernel/rcu/tree.c:3445 drop_sysctl_table+0x2f5/0x430 fs/proc/proc_sysctl.c:1731 unregister_sysctl_table+0x75/0x120 fs/proc/proc_sysctl.c:1769 unregister_net_sysctl_table+0x15/0x20 net/sysctl_net.c:175 neigh_sysctl_unregister+0x78/0x90 net/core/neighbour.c:3879 devinet_sysctl_unregister net/ipv4/devinet.c:2664 [inline] inetdev_destroy net/ipv4/devinet.c:329 [inline] inetdev_event+0x839/0x10a0 net/ipv4/devinet.c:1615 notifier_call_chain kernel/notifier.c:87 [inline] raw_notifier_call_chain+0xa1/0x110 kernel/notifier.c:455 call_netdevice_notifiers_info net/core/dev.c:2022 [inline] call_netdevice_notifiers_extack net/core/dev.c:2060 [inline] call_netdevice_notifiers net/core/dev.c:2074 [inline] unregister_netdevice_many+0x104a/0x1910 net/core/dev.c:11005 default_device_exit_batch+0x951/0x9f0 net/core/dev.c:11518 ops_exit_list net/core/net_namespace.c:177 [inline] cleanup_net+0x630/0xb10 net/core/net_namespace.c:604 process_one_work+0x717/0xc30 kernel/workqueue.c:2302 worker_thread+0xa4d/0x11d0 kernel/workqueue.c:2449 kthread+0x281/0x320 kernel/kthread.c:386 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 The buggy address belongs to the object at ffff88810e991800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 816 bytes inside of 1024-byte region [ffff88810e991800, ffff88810e991c00) The buggy address belongs to the physical page: page:ffffea00043a6400 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10e990 head:ffffea00043a6400 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x4000000000010200(slab|head|zone=1) raw: 4000000000010200 0000000000000000 dead000000000001 ffff888100043080 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 2689977589, free_ts 2645296735 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f5/0x210 mm/page_alloc.c:2673 prep_new_page+0x1c/0x110 mm/page_alloc.c:2680 get_page_from_freelist+0x2ca9/0x2d20 mm/page_alloc.c:4587 __alloc_pages+0x1fa/0x610 mm/page_alloc.c:5931 alloc_slab_page+0x6e/0xf0 include/linux/gfp.h:-1 allocate_slab mm/slub.c:1967 [inline] new_slab+0x98/0x3e0 mm/slub.c:2020 ___slab_alloc+0x70f/0xb70 mm/slub.c:3177 __slab_alloc+0x5e/0xa0 mm/slub.c:3263 slab_alloc_node mm/slub.c:3348 [inline] __kmem_cache_alloc_node+0x204/0x2d0 mm/slub.c:3423 __do_kmalloc_node mm/slab_common.c:937 [inline] __kmalloc+0xa4/0x1e0 mm/slab_common.c:951 kmalloc include/linux/slab.h:568 [inline] kzalloc include/linux/slab.h:699 [inline] __register_sysctl_table+0xd9/0xe50 fs/proc/proc_sysctl.c:1345 register_net_sysctl+0x23f/0x250 net/sysctl_net.c:169 neigh_sysctl_register+0x9a0/0xa80 net/core/neighbour.c:3860 ndisc_init+0x56/0x8c net/ipv6/ndisc.c:2038 inet6_init+0x269/0x68c net/ipv6/af_inet6.c:1153 do_one_initcall+0x1d6/0x580 init/main.c:1433 page last free stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] free_pages_prepare mm/page_alloc.c:1581 [inline] __free_pages_ok+0xbb0/0xca0 mm/page_alloc.c:1839 free_the_page mm/page_alloc.c:865 [inline] __free_pages+0xec/0x100 mm/page_alloc.c:6021 free_large_kmalloc+0xae/0xf0 mm/slab_common.c:915 kfree+0x8b/0xf0 mm/slab_common.c:984 kvfree+0x35/0x40 mm/util.c:639 btf_add_type kernel/bpf/btf.c:1581 [inline] btf_check_all_metas+0x5d1/0xad0 kernel/bpf/btf.c:4647 btf_parse_vmlinux+0x437/0x940 kernel/bpf/btf.c:5236 bpf_get_btf_vmlinux+0x41/0x60 kernel/bpf/verifier.c:15457 btf_get_module_btf+0x85/0x200 kernel/bpf/btf.c:7282 register_btf_kfunc_id_set+0x44/0x600 kernel/bpf/btf.c:7500 register_nf_conntrack_bpf+0x1b/0xb0 net/netfilter/nf_conntrack_bpf.c:499 nf_conntrack_init_start+0x3c3/0x460 net/netfilter/nf_conntrack_core.c:2772 nf_conntrack_standalone_init+0x11/0x100 net/netfilter/nf_conntrack_standalone.c:1213 do_one_initcall+0x1d6/0x580 init/main.c:1433 do_initcall_level+0x174/0x2df init/main.c:1506 do_initcalls+0x50/0x92 init/main.c:1522 Memory state around the buggy address: ffff88810e991a00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88810e991a80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88810e991b00: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc ^ ffff88810e991b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88810e991c00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== ---------------- Code disassembly (best guess): 0: ff c9 dec %ecx 2: 75 f2 jne 0xfffffff6 4: 89 d1 mov %edx,%ecx 6: c1 e9 03 shr $0x3,%ecx 9: 83 e2 07 and $0x7,%edx c: f3 48 a5 rep movsq %ds:(%rsi),%es:(%rdi) f: 89 d1 mov %edx,%ecx 11: f3 a4 rep movsb %ds:(%rsi),%es:(%rdi) 13: 31 c0 xor %eax,%eax 15: 0f 01 ca clac 18: c3 ret 19: 8d 0c ca lea (%rdx,%rcx,8),%ecx 1c: 89 ca mov %ecx,%edx 1e: eb 20 jmp 0x40 20: 0f 01 cb stac 23: 83 fa 40 cmp $0x40,%edx 26: 72 38 jb 0x60 28: 89 d1 mov %edx,%ecx * 2a: f3 a4 rep movsb %ds:(%rsi),%es:(%rdi) <-- trapping instruction 2c: 31 c0 xor %eax,%eax 2e: 0f 01 ca clac 31: c3 ret 32: 89 ca mov %ecx,%edx 34: eb 0a jmp 0x40 36: 90 nop 37: 90 nop 38: 90 nop 39: 90 nop 3a: 90 nop 3b: 90 nop 3c: 90 nop 3d: 90 nop 3e: 90 nop 3f: 90 nop