================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6bf/0x900 kernel/bpf/stackmap.c:271 Write of size 56 at addr ffff88805cfc5610 by task syz.1.5377/25077 CPU: 1 PID: 25077 Comm: syz.1.5377 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 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_a448e89f4c9ad9d1+0x30/0x4a 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:10547 __perf_event_overflow+0x447/0x630 kernel/events/core.c:9718 perf_swevent_overflow kernel/events/core.c:9794 [inline] perf_swevent_event+0x324/0x630 kernel/events/core.c:-1 do_perf_sw_event kernel/events/core.c:9935 [inline] ___perf_sw_event+0x4a7/0x730 kernel/events/core.c:9966 __perf_sw_event+0x139/0x270 kernel/events/core.c:9978 perf_sw_event include/linux/perf_event.h:1442 [inline] do_user_addr_fault+0x123e/0x12c0 arch/x86/mm/fault.c:1278 handle_page_fault arch/x86/mm/fault.c:1463 [inline] exc_page_fault+0x64/0x100 arch/x86/mm/fault.c:1516 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0010:do_strncpy_from_user lib/strncpy_from_user.c:41 [inline] RIP: 0010:strncpy_from_user+0xff/0x2d0 lib/strncpy_from_user.c:139 Code: 4c 89 ee e8 73 dc 2a fd 49 83 fd 07 0f 86 a1 00 00 00 4c 89 74 24 08 48 c7 44 24 10 f8 ff ff ff 45 31 e4 4c 89 3c 24 49 89 de <4f> 8b 3c 27 48 b8 ff fe fe fe fe fe fe fe 49 8d 1c 07 4c 89 fd 48 RSP: 0018:ffffc9000443fd40 EFLAGS: 00050246 RAX: ffffffff845c442d RBX: ffff888075e33320 RCX: ffff888064473c00 RDX: 0000000000000002 RSI: 0000000000000fe0 RDI: 0000000000000007 RBP: 0000000000000000 R08: ffffea0001d78c07 R09: 1ffffd40003af180 R10: dffffc0000000000 R11: fffff940003af181 R12: 0000000000000000 R13: 0000000000000fe0 R14: ffff888075e33320 R15: 0000000000000000 getname_flags+0xf6/0x500 fs/namei.c:151 do_sys_openat2+0xda/0x1d0 fs/open.c:1415 do_sys_open fs/open.c:1436 [inline] __do_sys_openat fs/open.c:1452 [inline] __se_sys_openat fs/open.c:1447 [inline] __x64_sys_openat+0x139/0x160 fs/open.c:1447 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 RIP: 0033:0x7fed2b39c799 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:00007fed2c217028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fed2b616090 RCX: 00007fed2b39c799 RDX: 0000000000123001 RSI: 0000000000000000 RDI: ffffffffffffff9c RBP: 00007fed2b432c99 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fed2b616128 R14: 00007fed2b616090 R15: 00007fff3941d0a8 Allocated by task 25077: 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:5458 __do_sys_bpf kernel/bpf/syscall.c:5580 [inline] __se_sys_bpf kernel/bpf/syscall.c:5578 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5578 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 nf_defrag_ipv6_disable+0x95/0xe0 net/ipv6/netfilter/nf_defrag_ipv6_hooks.c:174 nf_ct_netns_do_put net/netfilter/nf_conntrack_proto.c:545 [inline] nf_ct_netns_put+0x375/0x520 net/netfilter/nf_conntrack_proto.c:-1 nf_conncount_destroy+0x41/0x150 net/netfilter/nf_conncount.c:688 ovs_ct_limit_exit net/openvswitch/conntrack.c:1597 [inline] ovs_ct_exit+0x9c/0x200 net/openvswitch/conntrack.c:2000 ovs_exit_net+0xed/0x7a0 net/openvswitch/datapath.c:2686 ops_exit_list net/core/net_namespace.c:173 [inline] cleanup_net+0x70a/0xbb0 net/core/net_namespace.c:652 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 Second to 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_nat_unregister_fn+0x1f4/0x380 net/netfilter/nf_nat_core.c:1303 ipt_nat_unregister_lookups net/ipv4/netfilter/iptable_nat.c:101 [inline] iptable_nat_net_pre_exit+0x78/0x90 net/ipv4/netfilter/iptable_nat.c:131 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 ffff88805cfc5600 which belongs to the cache kmalloc-cg-64 of size 64 The buggy address is located 16 bytes inside of allocated 40-byte region [ffff88805cfc5600, ffff88805cfc5628) The buggy address belongs to the physical page: page:ffffea000173f140 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88805cfc5100 pfn:0x5cfc5 memcg:ffff8880259c2401 flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff888017c4da00 ffffea000073f800 dead000000000004 raw: ffff88805cfc5100 000000008020001f 00000001ffffffff ffff8880259c2401 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 5766, tgid 5766 (syz-executor), ts 72187140948, free_ts 17343165990 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 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc_node+0xa4/0x230 mm/slab_common.c:1014 kmalloc_node include/linux/slab.h:620 [inline] kvmalloc_node+0x70/0x180 mm/util.c:617 kvmalloc include/linux/slab.h:738 [inline] kvzalloc include/linux/slab.h:746 [inline] allocate_hook_entries_size net/netfilter/core.c:61 [inline] nf_hook_entries_grow+0x27d/0x6d0 net/netfilter/core.c:140 nf_hook_entries_insert_raw+0x4b/0x300 net/netfilter/core.c:204 nf_nat_register_fn+0x1d0/0x580 net/netfilter/nf_nat_core.c:1264 ip6t_nat_register_lookups net/ipv6/netfilter/ip6table_nat.c:79 [inline] ip6table_nat_table_init+0x14f/0x2d0 net/ipv6/netfilter/ip6table_nat.c:123 xt_find_table_lock+0x306/0x3e0 net/netfilter/x_tables.c:1259 xt_request_find_table_lock+0x26/0x100 net/netfilter/x_tables.c:1284 get_info net/ipv6/netfilter/ip6_tables.c:979 [inline] do_ip6t_get_ctl+0x717/0x1210 net/ipv6/netfilter/ip6_tables.c:1668 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 free_contig_range+0xa1/0x150 mm/page_alloc.c:6420 destroy_args+0x80/0x850 mm/debug_vm_pgtable.c:1015 debug_vm_pgtable+0x411/0x440 mm/debug_vm_pgtable.c:1400 do_one_initcall+0x242/0x790 init/main.c:1250 do_initcall_level+0x137/0x1f0 init/main.c:1312 do_initcalls+0x69/0xd0 init/main.c:1328 kernel_init_freeable+0x3ed/0x580 init/main.c:1565 kernel_init+0x1d/0x1c0 init/main.c:1455 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Memory state around the buggy address: ffff88805cfc5500: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88805cfc5580: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc >ffff88805cfc5600: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc ^ ffff88805cfc5680: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88805cfc5700: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ================================================================== ---------------- Code disassembly (best guess): 0: 4c 89 ee mov %r13,%rsi 3: e8 73 dc 2a fd call 0xfd2adc7b 8: 49 83 fd 07 cmp $0x7,%r13 c: 0f 86 a1 00 00 00 jbe 0xb3 12: 4c 89 74 24 08 mov %r14,0x8(%rsp) 17: 48 c7 44 24 10 f8 ff movq $0xfffffffffffffff8,0x10(%rsp) 1e: ff ff 20: 45 31 e4 xor %r12d,%r12d 23: 4c 89 3c 24 mov %r15,(%rsp) 27: 49 89 de mov %rbx,%r14 * 2a: 4f 8b 3c 27 mov (%r15,%r12,1),%r15 <-- trapping instruction 2e: 48 b8 ff fe fe fe fe movabs $0xfefefefefefefeff,%rax 35: fe fe fe 38: 49 8d 1c 07 lea (%r15,%rax,1),%rbx 3c: 4c 89 fd mov %r15,%rbp 3f: 48 rex.W