==================================================================
BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6fa/0x960 kernel/bpf/stackmap.c:274
Write of size 56 at addr ffff8881128af210 by task syz.0.1812/6866
CPU: 0 PID: 6866 Comm: syz.0.1812 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
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_1649ecc1a5870555+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:_perf_ioctl kernel/events/core.c:5778 [inline]
RIP: 0010:perf_ioctl+0x147a/0x1e70 kernel/events/core.c:5837
Code: 00 65 48 8b 04 25 28 00 00 00 48 3b 84 24 40 02 00 00 0f 85 3e 09 00 00 4c 89 f8 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 81 69 d7 ff 45 31 ff e9 6e ff ff ff e8 74 69 d7 ff 41 bf ea ff
RSP: 0018:ffffc90000ec7be0 EFLAGS: 00000246
RAX: ffffffff8199f9dd RBX: 0000000000000000 RCX: 0000000000000002
RDX: ffff88813435a880 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000ec7e80 R08: ffff88812552cf3f R09: 1ffff11024aa59e7
R10: dffffc0000000000 R11: ffffed1024aa59e8 R12: 0000000040042408
R13: dffffc0000000000 R14: fffff520001d8f8c R15: ffffc90000d8b000
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:870 [inline]
__se_sys_ioctl+0x12f/0x1b0 fs/ioctl.c:856
__x64_sys_ioctl+0x7b/0x90 fs/ioctl.c:856
x64_sys_call+0x58b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:17
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: 0033:0x7fe0ce59c819
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:00007fe0cf4a6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fe0ce815fa0 RCX: 00007fe0ce59c819
RDX: 0000000000000006 RSI: 0000000040042408 RDI: 0000000000000007
RBP: 00007fe0ce632c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe0ce816038 R14: 00007fe0ce815fa0 R15: 00007ffe3ca2a008
Allocated by task 6866:
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 ffff8881128af200
which belongs to the cache kmalloc-64 of size 64
The buggy address is located 16 bytes inside of
64-byte region [ffff8881128af200, ffff8881128af240)
The buggy address belongs to the physical page:
page:ffffea00044a2bc0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1128af
flags: 0x4000000000000200(slab|zone=1)
raw: 4000000000000200 ffffea000524ebc0 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 5788, tgid 5788 (syz-executor), ts 195993201850, free_ts 195977396043
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
__do_kmalloc_node mm/slab_common.c:937 [inline]
__kmalloc_node+0xa1/0x1e0 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]
simple_xattr_alloc+0x43/0xa0 fs/xattr.c:1008
shmem_initxattrs+0x8d/0x1e0 mm/shmem.c:3294
security_inode_init_security+0x2a9/0x3d0 security/security.c:1133
shmem_symlink+0xd0/0x4c0 mm/shmem.c:3166
vfs_symlink+0x261/0x3f0 fs/namei.c:4478
page last free stack trace:
reset_page_owner include/linux/page_owner.h:26 [inline]
free_pages_prepare mm/page_alloc.c:1578 [inline]
free_pcp_prepare mm/page_alloc.c:1652 [inline]
free_unref_page_prepare+0x742/0x750 mm/page_alloc.c:3618
free_unref_page+0x95/0x540 mm/page_alloc.c:3716
free_the_page mm/page_alloc.c:863 [inline]
__free_pages+0x67/0x100 mm/page_alloc.c:6014
__free_slab+0xca/0x1a0 mm/slub.c:2044
free_slab mm/slub.c:2059 [inline]
discard_slab mm/slub.c:2065 [inline]
__unfreeze_partials+0x160/0x190 mm/slub.c:2614
put_cpu_partial+0xa9/0x100 mm/slub.c:2690
__slab_free+0x1c4/0x280 mm/slub.c:3589
do_slab_free mm/slub.c:3666 [inline]
___cache_free+0xbf/0xd0 mm/slub.c:3722
qlink_free mm/kasan/quarantine.c:168 [inline]
qlist_free_all+0xc6/0x140 mm/kasan/quarantine.c:187
kasan_quarantine_reduce+0x14a/0x170 mm/kasan/quarantine.c:294
__kasan_slab_alloc+0x24/0x80 mm/kasan/common.c:311
kasan_slab_alloc include/linux/kasan.h:202 [inline]
slab_post_alloc_hook+0x4f/0x2d0 mm/slab.h:768
slab_alloc_node mm/slub.c:3382 [inline]
slab_alloc mm/slub.c:3392 [inline]
__kmem_cache_alloc_lru mm/slub.c:3399 [inline]
kmem_cache_alloc+0x16e/0x330 mm/slub.c:3408
kmem_cache_zalloc include/linux/slab.h:689 [inline]
locks_alloc_lock fs/locks.c:270 [inline]
flock_lock_inode+0x210/0x1370 fs/locks.c:1023
flock_lock_inode_wait fs/locks.c:2034 [inline]
locks_lock_inode_wait+0xf4/0x430 fs/locks.c:2061
locks_lock_file_wait include/linux/fs.h:1370 [inline]
__do_sys_flock fs/locks.c:2131 [inline]
__se_sys_flock+0x486/0x5a0 fs/locks.c:2085
Memory state around the buggy address:
ffff8881128af100: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc
ffff8881128af180: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
>ffff8881128af200: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
^
ffff8881128af280: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
ffff8881128af300: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
==================================================================
----------------
Code disassembly (best guess):
0: 00 65 48 add %ah,0x48(%rbp)
3: 8b 04 25 28 00 00 00 mov 0x28,%eax
a: 48 3b 84 24 40 02 00 cmp 0x240(%rsp),%rax
11: 00
12: 0f 85 3e 09 00 00 jne 0x956
18: 4c 89 f8 mov %r15,%rax
1b: 48 8d 65 d8 lea -0x28(%rbp),%rsp
1f: 5b pop %rbx
20: 41 5c pop %r12
22: 41 5d pop %r13
24: 41 5e pop %r14
26: 41 5f pop %r15
28: 5d pop %rbp
29: c3 ret
* 2a: e8 81 69 d7 ff call 0xffd769b0 <-- trapping instruction
2f: 45 31 ff xor %r15d,%r15d
32: e9 6e ff ff ff jmp 0xffffffa5
37: e8 74 69 d7 ff call 0xffd769b0
3c: 41 rex.B
3d: bf .byte 0xbf
3e: ea (bad)
3f: ff .byte 0xff