syzbot

==================================================================
BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6bf/0x900 kernel/bpf/stackmap.c:271
Write of size 56 at addr ffff88802f6b7210 by task syz.0.17/5912

CPU: 1 PID: 5912 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
 <#DB>
 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_a82986b851e905af+0x30/0x42
 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:10584
 __perf_event_overflow+0x447/0x630 kernel/events/core.c:9720
 perf_swevent_overflow kernel/events/core.c:9803 [inline]
 perf_swevent_event+0x319/0x570 kernel/events/core.c:9854
 perf_bp_event+0x319/0x430 kernel/events/core.c:10781
 hw_breakpoint_handler arch/x86/kernel/hw_breakpoint.c:555 [inline]
 hw_breakpoint_exceptions_notify+0x23e/0x670 arch/x86/kernel/hw_breakpoint.c:586
 notifier_call_chain+0x197/0x380 kernel/notifier.c:93
 atomic_notifier_call_chain+0xda/0x180 kernel/notifier.c:231
 notify_die+0x145/0x1a0 kernel/notifier.c:596
 notify_debug+0x2e/0x50 arch/x86/kernel/traps.c:1042
 exc_debug_kernel arch/x86/kernel/traps.c:1099 [inline]
 exc_debug+0xde/0x140 arch/x86/kernel/traps.c:1199
 asm_exc_debug+0x1e/0x40 arch/x86/include/asm/idtentry.h:644
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 <f3> a4 c3 48 8b 06 48 89 07 48 8d 47 08 48 83 e0 f8 48 29 f8 48 01
RSP: 0018:ffffc900035cfd50 EFLAGS: 00050202
RAX: ffffffff842a1e01 RBX: 0000000000000050 RCX: 000000000000000f
RDX: 0000000000000001 RSI: 0000200000000301 RDI: ffffc900035cfe01
RBP: ffffc900035cfee8 R08: ffffc900035cfe0f R09: 1ffff920006b9fc1
R10: dffffc0000000000 R11: fffff520006b9fc2 R12: 0000200000000310
R13: 0000000000000050 R14: ffffc900035cfdc0 R15: 00002000000002c0
 </#DB>
 <TASK>
 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]
 _copy_from_user+0x8b/0xe0 lib/usercopy.c:23
 copy_from_user include/linux/uaccess.h:183 [inline]
 copy_from_bpfptr_offset include/linux/bpfptr.h:53 [inline]
 copy_from_bpfptr include/linux/bpfptr.h:59 [inline]
 __sys_bpf+0x23e/0x890 kernel/bpf/syscall.c:5450
 __do_sys_bpf kernel/bpf/syscall.c:5581 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5579 [inline]
 __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5579
 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: 0033:0x7f1ba939c819
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:00007ffea39fce28 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f1ba9615fa0 RCX: 00007f1ba939c819
RDX: 0000000000000050 RSI: 00002000000002c0 RDI: 000000000000001c
RBP: 00007f1ba9432c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1ba9615fac R14: 00007f1ba9615fa0 R15: 00007f1ba9615fa0
 </TASK>

Allocated by task 5912:
 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:5459
 __do_sys_bpf kernel/bpf/syscall.c:5581 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5579 [inline]
 __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5579
 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 ffff88802f6b7200
 which belongs to the cache kmalloc-cg-64 of size 64
The buggy address is located 16 bytes inside of
 allocated 40-byte region [ffff88802f6b7200, ffff88802f6b7228)

The buggy address belongs to the physical page:
page:ffffea0000bdadc0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2f6b7
memcg:ffff888078482801
flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000800 ffff888017c4da00 dead000000000122 0000000000000000
raw: 0000000000000000 0000000080200020 00000001ffffffff ffff888078482801
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 5873, tgid 5873 (syz-executor), ts 77523596430, free_ts 77523321400
 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
 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:
 ffff88802f6b7100: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc
 ffff88802f6b7180: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc
>ffff88802f6b7200: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
                                  ^
 ffff88802f6b7280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88802f6b7300: fc fc fc fc fc fc fc 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