==================================================================
BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6fa/0x960 kernel/bpf/stackmap.c:274
Write of size 64 at addr ffff888133026810 by task syz.1.260/1229
CPU: 1 PID: 1229 Comm: syz.1.260 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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:365 [inline]
bpf_get_stackid_pe+0x2ee/0x400 kernel/bpf/stackmap.c:334
bpf_prog_2dda95fb29c238c3+0x21/0x31
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+0x3d0/0x5e0 kernel/events/core.c:10238
__perf_event_overflow+0x437/0x620 kernel/events/core.c:9448
perf_swevent_hrtimer+0x400/0x5b0 kernel/events/core.c:10879
__run_hrtimer kernel/time/hrtimer.c:1685 [inline]
__hrtimer_run_queues+0x3bb/0x8e0 kernel/time/hrtimer.c:1749
hrtimer_interrupt+0x3c7/0x8c0 kernel/time/hrtimer.c:1811
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
__sysvec_apic_timer_interrupt+0x11e/0x440 arch/x86/kernel/apic/apic.c:1124
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1118
asm_sysvec_apic_timer_interrupt+0x1b/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:instrument_atomic_read include/linux/instrumented.h:72 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline]
RIP: 0010:futex_hb_waiters_pending kernel/futex/futex.h:213 [inline]
RIP: 0010:futex_wake+0x174/0x8e0 kernel/futex/waitwake.c:163
Code: c9 e8 e0 5e ff ff 89 c3 31 ff 89 c6 e8 d5 c3 09 00 85 db 0f 85 31 05 00 00 4c 89 f7 e8 d5 5b ff ff 49 89 c7 f0 83 44 24 fc 00 <48> 89 c7 be 04 00 00 00 e8 df 13 4f 00 4c 89 f8 48 c1 e8 03 49 bc
RSP: 0018:ffffc900007bfb60 EFLAGS: 00000286
RAX: ffff888108926780 RBX: 0000000000000000 RCX: 00000000a284aac1
RDX: 00000000981e35a5 RSI: 000000000000008c RDI: ffffc900007bfbe8
RBP: ffffc900007bfcd0 R08: ffffc900007bfbf7 R09: ffffc900007bfbe0
R10: dffffc0000000000 R11: fffff520000f7f7f R12: 00007fa81f615fac
R13: 1ffff920000f7f78 R14: ffffc900007bfbe0 R15: ffff888108926780
do_futex+0x2bf/0x430 kernel/futex/syscalls.c:141
__do_sys_futex kernel/futex/syscalls.c:213 [inline]
__se_sys_futex+0x136/0x310 kernel/futex/syscalls.c:194
__x64_sys_futex+0xe5/0x100 kernel/futex/syscalls.c:194
x64_sys_call+0x7ec/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:203
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: 0033:0x7fa81f39c819
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:00007fa8202f50e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007fa81f615fa8 RCX: 00007fa81f39c819
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007fa81f615fac
RBP: 00007fa81f615fa0 R08: 0033f0506b010f4c R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa81f616038 R14: 00007ffffbf0ef00 R15: 00007ffffbf0efe8
Allocated by task 1229:
kasan_save_stack mm/kasan/common.c:46 [inline]
kasan_set_track+0x4b/0x70 mm/kasan/common.c:53
kasan_save_alloc_info+0x25/0x30 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+0x3a7/0x530 kernel/bpf/stackmap.c:117
find_and_alloc_map kernel/bpf/syscall.c:133 [inline]
map_create+0x49c/0xd80 kernel/bpf/syscall.c:1126
__sys_bpf+0x34e/0x850 kernel/bpf/syscall.c:4987
__do_sys_bpf kernel/bpf/syscall.c:5109 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5107 [inline]
__x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5107
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
The buggy address belongs to the object at ffff888133026800
which belongs to the cache kmalloc-64 of size 64
The buggy address is located 16 bytes inside of
64-byte region [ffff888133026800, ffff888133026840)
The buggy address belongs to the physical page:
page:ffffea0004cc0980 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888133026480 pfn:0x133026
flags: 0x4000000000000200(slab|zone=1)
raw: 4000000000000200 ffffea0004ca3500 dead000000000006 ffff888100042780
raw: ffff888133026480 000000008020001b 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 286, tgid 286 (syz-executor), ts 24820922026, free_ts 0
set_page_owner include/linux/page_owner.h:33 [inline]
post_alloc_hook+0x1f5/0x210 mm/page_alloc.c:2670
prep_new_page+0x1c/0x110 mm/page_alloc.c:2677
get_page_from_freelist+0x2d12/0x2d80 mm/page_alloc.c:4583
__alloc_pages+0x1fa/0x610 mm/page_alloc.c:5924
alloc_slab_page+0x6e/0xf0 include/linux/gfp.h:-1
allocate_slab mm/slub.c:1967 [inline]
new_slab+0x98/0x3d0 mm/slub.c:2020
___slab_alloc+0x6bd/0xb20 mm/slub.c:3177
__slab_alloc+0x5e/0xa0 mm/slub.c:3263
slab_alloc_node mm/slub.c:3348 [inline]
__kmem_cache_alloc_node+0x203/0x2c0 mm/slub.c:3423
kmalloc_trace+0x29/0xb0 mm/slab_common.c:1028
kmalloc include/linux/slab.h:563 [inline]
kzalloc include/linux/slab.h:699 [inline]
tnode_alloc net/ipv4/fib_trie.c:332 [inline]
tnode_new net/ipv4/fib_trie.c:385 [inline]
fib_insert_node net/ipv4/fib_trie.c:1130 [inline]
fib_insert_alias+0x381/0x10b0 net/ipv4/fib_trie.c:1164
fib_table_insert+0x81d/0x1df0 net/ipv4/fib_trie.c:1359
fib_magic net/ipv4/fib_frontend.c:1118 [inline]
fib_add_ifaddr+0x384/0xf10 net/ipv4/fib_frontend.c:1140
fib_inetaddr_event+0x15d/0x310 net/ipv4/fib_frontend.c:1454
notifier_call_chain kernel/notifier.c:87 [inline]
blocking_notifier_call_chain+0xcb/0x150 kernel/notifier.c:382
__inet_insert_ifa+0x856/0xa30 net/ipv4/devinet.c:568
page_owner free stack trace missing
Memory state around the buggy address:
ffff888133026700: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
ffff888133026780: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
>ffff888133026800: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
^
ffff888133026880: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
ffff888133026900: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc
==================================================================
----------------
Code disassembly (best guess):
0: c9 leave
1: e8 e0 5e ff ff call 0xffff5ee6
6: 89 c3 mov %eax,%ebx
8: 31 ff xor %edi,%edi
a: 89 c6 mov %eax,%esi
c: e8 d5 c3 09 00 call 0x9c3e6
11: 85 db test %ebx,%ebx
13: 0f 85 31 05 00 00 jne 0x54a
19: 4c 89 f7 mov %r14,%rdi
1c: e8 d5 5b ff ff call 0xffff5bf6
21: 49 89 c7 mov %rax,%r15
24: f0 83 44 24 fc 00 lock addl $0x0,-0x4(%rsp)
* 2a: 48 89 c7 mov %rax,%rdi <-- trapping instruction
2d: be 04 00 00 00 mov $0x4,%esi
32: e8 df 13 4f 00 call 0x4f1416
37: 4c 89 f8 mov %r15,%rax
3a: 48 c1 e8 03 shr $0x3,%rax
3e: 49 rex.WB
3f: bc .byte 0xbc