================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6fa/0x960 kernel/bpf/stackmap.c:274 Write of size 24 at addr ffff8881337f3fa8 by task syz.7.7185/30451 CPU: 1 PID: 30451 Comm: syz.7.7185 Tainted: G W syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/15/2026 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:377 [inline] bpf_get_stackid_pe+0x350/0x400 kernel/bpf/stackmap.c:334 bpf_prog_f1a392886e42970f+0x24/0x34 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:do_strncpy_from_user lib/strncpy_from_user.c:41 [inline] RIP: 0010:strncpy_from_user+0xd7/0x2c0 lib/strncpy_from_user.c:139 Code: 89 f6 e8 ec 2c e1 fe 49 83 fe 07 0f 86 a5 00 00 00 4c 89 75 c8 49 c7 c6 f8 ff ff ff 45 31 ff 4c 89 65 c0 4c 89 6d d0 4d 89 fd <4b> 8b 1c 3c 48 b8 ff fe fe fe fe fe fe fe 4c 8d 3c 03 49 89 dc 49 RSP: 0018:ffffc90000e77b28 EFLAGS: 00050246 RAX: ffffffff829049f4 RBX: 000000000000007f RCX: ffff88812511a880 RDX: 0000000000000002 RSI: 000000000000007f RDI: 0000000000000007 RBP: ffffc90000e77b70 R08: ffff88812511a880 R09: 0000000000000002 R10: 0000000000000001 R11: 0000000000000002 R12: 0000000000000000 R13: 0000000000000000 R14: fffffffffffffff8 R15: 0000000000000000 strncpy_from_bpfptr include/linux/bpfptr.h:85 [inline] bpf_prog_load+0x1f1/0x1670 kernel/bpf/syscall.c:2508 __sys_bpf+0x57b/0x850 kernel/bpf/syscall.c:5006 __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 RIP: 0033:0x7f8de259fb19 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:00007f8de3538028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f8de2825fa0 RCX: 00007f8de259fb19 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005 RBP: 00007f8de2637b70 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f8de2826038 R14: 00007f8de2825fa0 R15: 00007ffca8410248 Allocated by task 30451: 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 __call_rcu_common kernel/rcu/tree.c:2807 [inline] call_rcu+0xcf/0xf50 kernel/rcu/tree.c:2926 nf_hook_entries_free net/netfilter/core.c:94 [inline] __nf_unregister_net_hook+0x486/0x610 net/netfilter/core.c:520 nf_unregister_net_hook net/netfilter/core.c:-1 [inline] nf_unregister_net_hooks+0xe2/0x150 net/netfilter/core.c:607 selinux_nf_unregister+0x21/0x30 security/selinux/hooks.c:7499 ops_exit_list net/core/net_namespace.c:172 [inline] cleanup_net+0x5b0/0xb10 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 Second to 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 __call_rcu_common kernel/rcu/tree.c:2807 [inline] call_rcu+0xcf/0xf50 kernel/rcu/tree.c:2926 release_probes kernel/tracepoint.c:164 [inline] tracepoint_remove_func kernel/tracepoint.c:460 [inline] tracepoint_probe_unregister+0x866/0x8e0 kernel/tracepoint.c:553 trace_event_reg+0x225/0x270 kernel/trace/trace_events.c:-1 perf_trace_event_unreg+0xcc/0x1c0 kernel/trace/trace_event_perf.c:162 perf_trace_destroy+0xbe/0x180 kernel/trace/trace_event_perf.c:241 tp_perf_event_destroy+0x15/0x20 kernel/events/core.c:10055 _free_event+0x9b7/0xcd0 kernel/events/core.c:5045 put_event kernel/events/core.c:5139 [inline] perf_event_release_kernel+0x7ab/0x830 kernel/events/core.c:5264 perf_release+0x3b/0x40 kernel/events/core.c:5274 __fput+0x1fd/0x8f0 fs/file_table.c:320 ____fput+0x15/0x20 fs/file_table.c:348 task_work_run+0x1e1/0x250 kernel/task_work.c:203 exit_task_work include/linux/task_work.h:39 [inline] do_exit+0xb0d/0x29f0 kernel/exit.c:896 __do_sys_exit kernel/exit.c:1006 [inline] __se_sys_exit kernel/exit.c:1004 [inline] __cfi___ia32_sys_exit+0x0/0x10 kernel/exit.c:1004 x64_sys_call+0x67/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:61 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 ffff8881337f3f80 which belongs to the cache kmalloc-64 of size 64 The buggy address is located 40 bytes inside of 64-byte region [ffff8881337f3f80, ffff8881337f3fc0) The buggy address belongs to the physical page: page:ffffea0004cdfcc0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1337f3 flags: 0x4000000000000200(slab|zone=1) raw: 4000000000000200 ffffea0004d2a280 dead000000000002 ffff888100042780 raw: 0000000000000000 0000000000200020 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 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 291, tgid 291 (syz-executor), ts 25452647168, free_ts 0 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_node+0xa2/0x1e0 mm/slab_common.c:945 kmalloc_node include/linux/slab.h:589 [inline] kvmalloc_node+0x28a/0x460 mm/util.c:592 kvmalloc include/linux/slab.h:716 [inline] kvzalloc include/linux/slab.h:724 [inline] allocate_hook_entries_size net/netfilter/core.c:67 [inline] nf_hook_entries_grow+0x32a/0x770 net/netfilter/core.c:134 nf_hook_entries_insert_raw+0x4e/0x300 net/netfilter/core.c:198 nf_nat_register_fn+0x20e/0x580 net/netfilter/nf_nat_core.c:1058 nf_nat_ipv4_register_fn+0x4b/0x60 net/netfilter/nf_nat_proto.c:824 ipt_nat_register_lookups net/ipv4/netfilter/iptable_nat.c:77 [inline] iptable_nat_table_init+0x19d/0x330 net/ipv4/netfilter/iptable_nat.c:121 page_owner free stack trace missing Memory state around the buggy address: ffff8881337f3e80: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc ffff8881337f3f00: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc >ffff8881337f3f80: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc ^ ffff8881337f4000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8881337f4080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== ---------------- Code disassembly (best guess): 0: 89 f6 mov %esi,%esi 2: e8 ec 2c e1 fe call 0xfee12cf3 7: 49 83 fe 07 cmp $0x7,%r14 b: 0f 86 a5 00 00 00 jbe 0xb6 11: 4c 89 75 c8 mov %r14,-0x38(%rbp) 15: 49 c7 c6 f8 ff ff ff mov $0xfffffffffffffff8,%r14 1c: 45 31 ff xor %r15d,%r15d 1f: 4c 89 65 c0 mov %r12,-0x40(%rbp) 23: 4c 89 6d d0 mov %r13,-0x30(%rbp) 27: 4d 89 fd mov %r15,%r13 * 2a: 4b 8b 1c 3c mov (%r12,%r15,1),%rbx <-- trapping instruction 2e: 48 b8 ff fe fe fe fe movabs $0xfefefefefefefeff,%rax 35: fe fe fe 38: 4c 8d 3c 03 lea (%rbx,%rax,1),%r15 3c: 49 89 dc mov %rbx,%r12 3f: 49 rex.WB