================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6c9/0x920 kernel/bpf/stackmap.c:274 Write of size 80 at addr ffff88801c750890 by task syz.0.4393/20212 CPU: 1 PID: 20212 Comm: syz.0.4393 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 print_address_description mm/kasan/report.c:316 [inline] print_report+0xa8/0x210 mm/kasan/report.c:420 kasan_report+0x10b/0x140 mm/kasan/report.c:524 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x235/0x290 mm/kasan/generic.c:189 memcpy+0x3c/0x60 mm/kasan/shadow.c:66 __bpf_get_stackid+0x6c9/0x920 kernel/bpf/stackmap.c:274 ____bpf_get_stackid_pe kernel/bpf/stackmap.c:365 [inline] bpf_get_stackid_pe+0x33f/0x400 kernel/bpf/stackmap.c:334 bpf_prog_ceda4e53fcf21ae1+0x28/0x40 bpf_dispatcher_nop_func include/linux/bpf.h:1012 [inline] __bpf_prog_run include/linux/filter.h:596 [inline] bpf_prog_run include/linux/filter.h:614 [inline] bpf_overflow_handler+0x6e8/0x7c0 kernel/events/core.c:10286 __perf_event_overflow+0x448/0x610 kernel/events/core.c:9496 do_perf_sw_event kernel/events/core.c:9713 [inline] ___perf_sw_event+0x49e/0x6e0 kernel/events/core.c:9744 __perf_sw_event+0x135/0x260 kernel/events/core.c:9756 perf_sw_event include/linux/perf_event.h:1254 [inline] do_user_addr_fault+0xaea/0xb10 arch/x86/mm/fault.c:1284 handle_page_fault arch/x86/mm/fault.c:1429 [inline] exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1482 asm_exc_page_fault+0x22/0x30 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:ffffc90004337788 EFLAGS: 00050202 RAX: ffffffff840efa01 RBX: 000000000000fec9 RCX: 000000000000df09 RDX: 000000000000fec9 RSI: 0000200000002000 RDI: ffffc900044aafc0 RBP: 0000000000000000 R08: ffffc900044b8ec8 R09: 1ffff920008971d9 R10: dffffc0000000000 R11: fffff520008971da R12: 00007ffffffef137 R13: 0000000000000000 R14: 0000200000000040 R15: ffffc900044a9000 copy_user_generic arch/x86/include/asm/uaccess_64.h:37 [inline] raw_copy_from_user arch/x86/include/asm/uaccess_64.h:52 [inline] copyin+0xe7/0x120 lib/iov_iter.c:183 _copy_from_iter+0x447/0x1130 lib/iov_iter.c:631 copy_from_iter include/linux/uio.h:187 [inline] copy_from_iter_full include/linux/uio.h:194 [inline] memcpy_from_msg include/linux/skbuff.h:4076 [inline] netlink_sendmsg+0x755/0xbd0 net/netlink/af_netlink.c:1857 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:730 [inline] ____sys_sendmsg+0x5be/0x970 net/socket.c:2518 ___sys_sendmsg+0x2a2/0x360 net/socket.c:2572 __sys_sendmsg net/socket.c:2601 [inline] __do_sys_sendmsg net/socket.c:2610 [inline] __se_sys_sendmsg+0x1bb/0x2a0 net/socket.c:2608 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: 0033:0x7f5ba639c799 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:00007f5ba7302028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f5ba6616090 RCX: 00007f5ba639c799 RDX: 0000000000000000 RSI: 0000200000000000 RDI: 000000000000000b RBP: 00007f5ba6432c99 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f5ba6616128 R14: 00007f5ba6616090 R15: 00007ffd62843a38 Allocated by task 20207: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 ____kasan_kmalloc mm/kasan/common.c:375 [inline] __kasan_kmalloc+0x8e/0xa0 mm/kasan/common.c:384 kasan_kmalloc include/linux/kasan.h:211 [inline] __do_kmalloc_node mm/slab_common.c:936 [inline] __kmalloc_node+0xb0/0x240 mm/slab_common.c:943 kmalloc_node include/linux/slab.h:589 [inline] __bpf_map_area_alloc kernel/bpf/syscall.c:328 [inline] bpf_map_area_alloc+0x47/0xe0 kernel/bpf/syscall.c:341 prealloc_elems_and_freelist+0x86/0x1c0 kernel/bpf/stackmap.c:51 stack_map_alloc+0x390/0x520 kernel/bpf/stackmap.c:117 find_and_alloc_map kernel/bpf/syscall.c:133 [inline] map_create+0x534/0x1000 kernel/bpf/syscall.c:1149 __sys_bpf+0x38b/0x780 kernel/bpf/syscall.c:5012 __do_sys_bpf kernel/bpf/syscall.c:5134 [inline] __se_sys_bpf kernel/bpf/syscall.c:5132 [inline] __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5132 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+0xb2/0xc0 mm/kasan/generic.c:486 call_rcu+0x14f/0x990 kernel/rcu/tree.c:2849 nf_hook_entries_free net/netfilter/core.c:88 [inline] __nf_register_net_hook+0x788/0x910 net/netfilter/core.c:445 nf_register_net_hook+0xae/0x190 net/netfilter/core.c:566 nf_register_net_hooks+0x40/0x1a0 net/netfilter/core.c:582 nf_ct_netns_do_get+0x3bc/0x5b0 net/netfilter/nf_conntrack_proto.c:482 nf_ct_netns_inet_get+0x1f/0x150 net/netfilter/nf_conntrack_proto.c:591 nf_conncount_init+0x123/0x380 net/netfilter/nf_conncount.c:640 ovs_ct_limit_init net/openvswitch/conntrack.c:1902 [inline] ovs_ct_init+0x312/0x480 net/openvswitch/conntrack.c:2311 ovs_init_net+0x1e2/0x240 net/openvswitch/datapath.c:2613 ops_init+0x355/0x5f0 net/core/net_namespace.c:138 setup_net+0x4f2/0xbd0 net/core/net_namespace.c:336 copy_net_ns+0x348/0x5b0 net/core/net_namespace.c:508 create_new_namespaces+0x3d3/0x6f0 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x116/0x160 kernel/nsproxy.c:226 ksys_unshare+0x4ca/0x8b0 kernel/fork.c:3282 __do_sys_unshare kernel/fork.c:3353 [inline] __se_sys_unshare kernel/fork.c:3351 [inline] __x64_sys_unshare+0x34/0x40 kernel/fork.c:3351 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 ffff88801c750880 which belongs to the cache kmalloc-cg-64 of size 64 The buggy address is located 16 bytes inside of 64-byte region [ffff88801c750880, ffff88801c7508c0) The buggy address belongs to the physical page: page:ffffea000071d400 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1c750 memcg:ffff88807b6df001 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 ffffea00008f5480 dead000000000002 ffff888017442780 raw: 0000000000000000 0000000080200020 00000001ffffffff ffff88807b6df001 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 6739788105, free_ts 0 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2559 prep_new_page mm/page_alloc.c:2566 [inline] get_page_from_freelist+0x1a1e/0x1ab0 mm/page_alloc.c:4357 __alloc_pages+0x1ec/0x4f0 mm/page_alloc.c:5657 alloc_page_interleave+0x24/0x1e0 mm/mempolicy.c:2115 alloc_slab_page+0x5d/0x160 mm/slub.c:1799 allocate_slab mm/slub.c:1944 [inline] new_slab+0x87/0x2c0 mm/slub.c:1997 ___slab_alloc+0xbc6/0x1240 mm/slub.c:3154 __slab_alloc mm/slub.c:3240 [inline] slab_alloc_node mm/slub.c:3325 [inline] __kmem_cache_alloc_node+0x1a0/0x260 mm/slub.c:3398 __do_kmalloc_node mm/slab_common.c:935 [inline] __kmalloc_node+0xa0/0x240 mm/slab_common.c:943 kmalloc_node include/linux/slab.h:589 [inline] kvmalloc_node+0x6c/0x180 mm/util.c:581 kvmalloc include/linux/slab.h:716 [inline] kvzalloc include/linux/slab.h:724 [inline] allocate_hook_entries_size net/netfilter/core.c:61 [inline] nf_hook_entries_grow+0x309/0x730 net/netfilter/core.c:128 __nf_register_net_hook+0x2c9/0x910 net/netfilter/core.c:423 nf_register_net_hook+0xae/0x190 net/netfilter/core.c:566 nf_register_net_hooks+0x40/0x1a0 net/netfilter/core.c:582 ops_init+0x355/0x5f0 net/core/net_namespace.c:138 __register_pernet_operations net/core/net_namespace.c:1209 [inline] register_pernet_operations+0x2af/0x610 net/core/net_namespace.c:1282 page_owner free stack trace missing Memory state around the buggy address: ffff88801c750780: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc ffff88801c750800: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc >ffff88801c750880: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc ^ ffff88801c750900: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc ffff88801c750980: fa fb fb fb fb fb fb fb 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