================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6bf/0x900 kernel/bpf/stackmap.c:271 Write of size 48 at addr ffff88801af67a90 by task syz.0.181/6319 CPU: 0 PID: 6319 Comm: syz.0.181 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_88b6ce719581ac33+0x29/0x39 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_hrtimer+0x4aa/0x570 kernel/events/core.c:11188 __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+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:212 Code: 00 0f 0b 0f 1f 80 00 00 00 00 f3 0f 1e fa 53 48 89 fb e8 13 00 00 00 48 8b 3d bc d4 03 0d 48 89 de 5b e9 33 5f 57 00 cc cc cc 0f 1e fa 48 8b 04 24 65 48 8b 0d 50 99 7c 7e 65 8b 15 51 99 7c RSP: 0018:ffffc9000f847bf8 EFLAGS: 00000246 RAX: ffffffff81b1788f RBX: 0000000000000000 RCX: 0000000000000002 RDX: ffff88807aeb0000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000f847ed8 R08: ffff8880268ed1df R09: 1ffff11004d1da3b R10: dffffc0000000000 R11: ffffed1004d1da3c R12: 0000000040042408 R13: dffffc0000000000 R14: fffff52001f08f94 R15: ffffc90010ceb000 _perf_ioctl kernel/events/core.c:6015 [inline] perf_ioctl+0xf3c/0x24a0 kernel/events/core.c:6074 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857 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: 0033:0x7f4b54f9c799 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:00007f4b55e9c028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f4b55215fa0 RCX: 00007f4b54f9c799 RDX: 0000000000000004 RSI: 0000000040042408 RDI: 0000000000000005 RBP: 00007f4b55032c99 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f4b55216038 R14: 00007f4b55215fa0 R15: 00007ffd2fc8e108 Allocated by task 6319: 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_hook_entries_free net/netfilter/core.c:88 [inline] __nf_register_net_hook+0x788/0x910 net/netfilter/core.c:457 nf_register_net_hook+0xb2/0x190 net/netfilter/core.c:578 nf_register_net_hooks+0x44/0x1b0 net/netfilter/core.c:594 nf_ct_netns_do_get+0x3c0/0x5c0 net/netfilter/nf_conntrack_proto.c:457 nf_ct_netns_inet_get+0x1f/0x150 net/netfilter/nf_conntrack_proto.c:566 nf_conncount_init+0x127/0x380 net/netfilter/nf_conncount.c:640 ovs_ct_limit_init net/openvswitch/conntrack.c:1580 [inline] ovs_ct_init+0x316/0x490 net/openvswitch/conntrack.c:1989 ovs_init_net+0x1e6/0x250 net/openvswitch/datapath.c:2644 ops_init+0x397/0x640 net/core/net_namespace.c:139 setup_net+0x3b6/0xa30 net/core/net_namespace.c:343 copy_net_ns+0x36d/0x5e0 net/core/net_namespace.c:520 create_new_namespaces+0x3d3/0x6f0 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x11a/0x160 kernel/nsproxy.c:228 ksys_unshare+0x4ce/0x8b0 kernel/fork.c:3439 __do_sys_unshare kernel/fork.c:3510 [inline] __se_sys_unshare kernel/fork.c:3508 [inline] __x64_sys_unshare+0x38/0x40 kernel/fork.c:3508 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 The buggy address belongs to the object at ffff88801af67a80 which belongs to the cache kmalloc-cg-64 of size 64 The buggy address is located 16 bytes inside of allocated 40-byte region [ffff88801af67a80, ffff88801af67aa8) The buggy address belongs to the physical page: page:ffffea00006bd9c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88801af67000 pfn:0x1af67 memcg:ffff8880268f3601 flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff888017c4da00 ffffea0000bcb580 0000000000000004 raw: ffff88801af67000 000000008020001e 00000001ffffffff ffff8880268f3601 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 1, tgid 1 (swapper/0), ts 5276937936, free_ts 0 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_page_interleave+0x24/0x1e0 mm/mempolicy.c:2120 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_register_net_hook+0x2c9/0x910 net/netfilter/core.c:435 nf_register_net_hook+0xb2/0x190 net/netfilter/core.c:578 nf_register_net_hooks+0x44/0x1b0 net/netfilter/core.c:594 ops_init+0x397/0x640 net/core/net_namespace.c:139 __register_pernet_operations net/core/net_namespace.c:1265 [inline] register_pernet_operations+0x2b3/0x610 net/core/net_namespace.c:1338 page_owner free stack trace missing Memory state around the buggy address: ffff88801af67980: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88801af67a00: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc >ffff88801af67a80: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc ^ ffff88801af67b00: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88801af67b80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ================================================================== ---------------- Code disassembly (best guess), 1 bytes skipped: 0: 0f 0b ud2 2: 0f 1f 80 00 00 00 00 nopl 0x0(%rax) 9: f3 0f 1e fa endbr64 d: 53 push %rbx e: 48 89 fb mov %rdi,%rbx 11: e8 13 00 00 00 call 0x29 16: 48 8b 3d bc d4 03 0d mov 0xd03d4bc(%rip),%rdi # 0xd03d4d9 1d: 48 89 de mov %rbx,%rsi 20: 5b pop %rbx 21: e9 33 5f 57 00 jmp 0x575f59 26: cc int3 27: cc int3 28: cc int3 * 29: f3 0f 1e fa endbr64 <-- trapping instruction 2d: 48 8b 04 24 mov (%rsp),%rax 31: 65 48 8b 0d 50 99 7c mov %gs:0x7e7c9950(%rip),%rcx # 0x7e7c9989 38: 7e 39: 65 gs 3a: 8b .byte 0x8b 3b: 15 .byte 0x15 3c: 51 push %rcx 3d: 99 cltd 3e: 7c .byte 0x7c