================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6bf/0x900 kernel/bpf/stackmap.c:271 Write of size 72 at addr ffff88801b3d3410 by task syz.1.278/6746 CPU: 0 PID: 6746 Comm: syz.1.278 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 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_16fa1569821187d5+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_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:rep_movs_alternative+0x4a/0x90 arch/x86/lib/copy_user_64.S:71 Code: 75 f1 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 8b 06 48 89 07 48 83 c6 08 48 83 c7 08 83 e9 08 74 df 83 f9 08 73 e8 eb c9 a4 c3 48 8b 06 48 89 07 48 8d 47 08 48 83 e0 f8 48 29 f8 48 01 RSP: 0018:ffffc90010347938 EFLAGS: 00050206 RAX: ffffffff84272301 RBX: 0000000000033fe0 RCX: 000000000002ffe0 RDX: 0000000000000001 RSI: 0000200000004000 RDI: ffffc9001040d000 RBP: ffffc90010347a90 R08: ffffc9001043cfdf R09: 1ffff920020879fb R10: dffffc0000000000 R11: fffff520020879fc R12: ffffc90010409000 R13: 0000200000000000 R14: ffffc90010347c18 R15: 1ffff92002068f83 copy_user_generic arch/x86/include/asm/uaccess_64.h:112 [inline] raw_copy_from_user arch/x86/include/asm/uaccess_64.h:127 [inline] copyin lib/iov_iter.c:193 [inline] _copy_from_iter+0x24e/0x12e0 lib/iov_iter.c:390 copy_from_iter include/linux/uio.h:209 [inline] copy_from_iter_full include/linux/uio.h:216 [inline] memcpy_from_msg include/linux/skbuff.h:4077 [inline] netlink_sendmsg+0x76b/0xbf0 net/netlink/af_netlink.c:1879 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] sock_write_iter+0x2df/0x420 net/socket.c:1160 call_write_iter include/linux/fs.h:2018 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x46c/0x990 fs/read_write.c:584 ksys_write+0x150/0x260 fs/read_write.c:637 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: 0033:0x7fe35cb9bf79 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:00007fe35d9c6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fe35ce16090 RCX: 00007fe35cb9bf79 RDX: 0000000000033fe0 RSI: 0000200000000000 RDI: 0000000000000007 RBP: 00007fe35cc327e0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fe35ce16128 R14: 00007fe35ce16090 R15: 00007ffeba058ed8 Allocated by task 6749: 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 The buggy address belongs to the object at ffff88801b3d3400 which belongs to the cache kmalloc-cg-64 of size 64 The buggy address is located 16 bytes inside of allocated 40-byte region [ffff88801b3d3400, ffff88801b3d3428) The buggy address belongs to the physical page: page:ffffea00006cf4c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1b3d3 memcg:ffff888028068201 anon flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff888017c4da00 0000000000000000 0000000000000001 raw: 0000000000000000 0000000080200020 00000001ffffffff ffff888028068201 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 5774, tgid 5774 (syz-executor), ts 83246190861, free_ts 83245387476 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:4486 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+0xd4/0x2d0 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 vfree+0x1a6/0x320 mm/vmalloc.c:2868 copy_entries_to_user net/ipv6/netfilter/ip6_tables.c:882 [inline] get_entries net/ipv6/netfilter/ip6_tables.c:1039 [inline] do_ip6t_get_ctl+0xf21/0x1210 net/ipv6/netfilter/ip6_tables.c:1677 nf_getsockopt+0x262/0x280 net/netfilter/nf_sockopt.c:116 ipv6_getsockopt+0x226/0x2e0 net/ipv6/ipv6_sockglue.c:1499 do_sock_getsockopt+0x379/0x450 net/socket.c:2383 __sys_getsockopt net/socket.c:2412 [inline] __do_sys_getsockopt net/socket.c:2422 [inline] __se_sys_getsockopt net/socket.c:2419 [inline] __x64_sys_getsockopt+0x1d6/0x280 net/socket.c:2419 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 Memory state around the buggy address: ffff88801b3d3300: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88801b3d3380: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc >ffff88801b3d3400: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc ^ ffff88801b3d3480: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc ffff88801b3d3500: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc ================================================================== ---------------- Code disassembly (best guess): 0: 75 f1 jne 0xfffffff3 2: c3 ret 3: 66 2e 0f 1f 84 00 00 cs nopw 0x0(%rax,%rax,1) a: 00 00 00 d: 0f 1f 00 nopl (%rax) 10: 48 8b 06 mov (%rsi),%rax 13: 48 89 07 mov %rax,(%rdi) 16: 48 83 c6 08 add $0x8,%rsi 1a: 48 83 c7 08 add $0x8,%rdi 1e: 83 e9 08 sub $0x8,%ecx 21: 74 df je 0x2 23: 83 f9 08 cmp $0x8,%ecx 26: 73 e8 jae 0x10 28: eb c9 jmp 0xfffffff3 * 2a: f3 a4 rep movsb %ds:(%rsi),%es:(%rdi) <-- trapping instruction 2c: c3 ret 2d: 48 8b 06 mov (%rsi),%rax 30: 48 89 07 mov %rax,(%rdi) 33: 48 8d 47 08 lea 0x8(%rdi),%rax 37: 48 83 e0 f8 and $0xfffffffffffffff8,%rax 3b: 48 29 f8 sub %rdi,%rax 3e: 48 rex.W 3f: 01 .byte 0x1