==================================================================
BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6c7/0x900 kernel/bpf/stackmap.c:271
Write of size 48 at addr ffff8880268055d0 by task syz.1.6779/29050
CPU: 1 PID: 29050 Comm: syz.1.6779 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
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+0x6c7/0x900 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_52ee0099233a1ca4+0x29/0x39
bpf_dispatcher_nop_func include/linux/bpf.h:1224 [inline]
__bpf_prog_run include/linux/filter.h:617 [inline]
bpf_prog_run include/linux/filter.h:624 [inline]
bpf_overflow_handler+0x1fc/0x510 kernel/events/core.c:10576
__perf_event_overflow+0x461/0x660 kernel/events/core.c:9712
perf_event_overflow kernel/events/core.c:9733 [inline]
perf_swevent_hrtimer+0x437/0x610 kernel/events/core.c:11222
__run_hrtimer kernel/time/hrtimer.c:1754 [inline]
__hrtimer_run_queues+0x4e8/0xc10 kernel/time/hrtimer.c:1818
hrtimer_interrupt+0x39d/0x980 kernel/time/hrtimer.c:1880
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1077 [inline]
__sysvec_apic_timer_interrupt+0xfb/0x3b0 arch/x86/kernel/apic/apic.c:1094
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1088
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:put_ctx+0x0/0x1c0 kernel/events/core.c:1218
Code: 5e 5d c3 e8 72 5b d9 ff be 02 00 00 00 eb 0a e8 66 5b d9 ff be 01 00 00 00 48 89 df 5b 41 5e 5d e9 95 d6 83 02 0f 1f 44 00 00 <55> 41 57 41 56 53 48 89 fb e8 42 5b d9 ff 4c 8d b3 2c 01 00 00 4c
RSP: 0018:ffffc9000b8d7c18 EFLAGS: 00000246
RAX: 0c0b8881a755f200 RBX: ffff88801f34b400 RCX: ffffffff8a956694
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff88801f34b400
RBP: ffffc9000b8d7ed8 R08: ffffc9000b8d7ba7 R09: 1ffff9200171af74
R10: dffffc0000000000 R11: fffff5200171af75 R12: 0000000040042408
R13: dffffc0000000000 R14: fffff5200171af94 R15: 0000000000000000
perf_event_ctx_unlock kernel/events/core.c:1329 [inline]
perf_ioctl+0x20e0/0x24b0 kernel/events/core.c:6069
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:871 [inline]
__se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fa28499e019
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:00007fa285946028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fa284c25fa0 RCX: 00007fa28499e019
RDX: 0000000000000008 RSI: 0000000040042408 RDI: 0000000000000009
RBP: 00007fa284a3500c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa284c26038 R14: 00007fa284c25fa0 R15: 00007ffd1d696a88
Allocated by task 29050:
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+0xb6/0x240 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+0x32b/0x4b0 kernel/bpf/stackmap.c:114
map_create+0x877/0x12f0 kernel/bpf/syscall.c:1247
__sys_bpf+0x651/0x890 kernel/bpf/syscall.c:5460
__do_sys_bpf kernel/bpf/syscall.c:5582 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5580 [inline]
__x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5580
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
The buggy address belongs to the object at ffff8880268055c0
which belongs to the cache kmalloc-cg-32 of size 32
The buggy address is located 16 bytes inside of
allocated 24-byte region [ffff8880268055c0, ffff8880268055d8)
The buggy address belongs to the physical page:
page:ffffea00009a0140 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888026805f40 pfn:0x26805
memcg:ffff88801f360801
flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000800 ffff888017c4d8c0 ffffea0001f66940 dead000000000002
raw: ffff888026805f40 0000000080400026 00000001ffffffff ffff88801f360801
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x116cc0(GFP_USER|__GFP_NOWARN|__GFP_RETRY_MAYFAIL|__GFP_NORETRY), pid 5765, tgid 5765 (udevd), ts 113957170757, free_ts 113956003476
set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook+0x1c1/0x200 mm/page_alloc.c:1582
prep_new_page mm/page_alloc.c:1589 [inline]
get_page_from_freelist+0x2181/0x22a0 mm/page_alloc.c:3221
__alloc_pages+0x1f0/0x460 mm/page_alloc.c:4501
alloc_slab_page+0x5d/0x180 mm/slub.c:1881
allocate_slab mm/slub.c:2028 [inline]
new_slab+0x87/0x2d0 mm/slub.c:2081
___slab_alloc+0xc5c/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+0x11f/0x250 mm/slub.c:3534
__do_kmalloc_node mm/slab_common.c:1006 [inline]
__kmalloc+0xa7/0x240 mm/slab_common.c:1020
kmalloc include/linux/slab.h:604 [inline]
inotify_handle_inode_event+0x18a/0x560 fs/notify/inotify/inotify_fsnotify.c:96
inotify_ignored_and_remove_idr+0x29/0x70 fs/notify/inotify/inotify_user.c:527
__do_sys_inotify_rm_watch fs/notify/inotify/inotify_user.c:818 [inline]
__se_sys_inotify_rm_watch+0x150/0x210 fs/notify/inotify/inotify_user.c:795
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
page last free stack trace:
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1182 [inline]
free_unref_page_prepare+0x7d7/0x8f0 mm/page_alloc.c:2366
free_unref_page+0x32/0x2e0 mm/page_alloc.c:2459
vfree+0x1a7/0x340 mm/vmalloc.c:2868
process_one_work kernel/workqueue.c:2653 [inline]
process_scheduled_works+0xa60/0x1600 kernel/workqueue.c:2730
worker_thread+0xa5e/0xfe0 kernel/workqueue.c:2811
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
Memory state around the buggy address:
ffff888026805480: fb fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
ffff888026805500: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
>ffff888026805580: fb fb fb fb fc fc fc fc 00 00 00 fc fc fc fc fc
^
ffff888026805600: fa fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
ffff888026805680: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
==================================================================
----------------
Code disassembly (best guess):
0: 5e pop %rsi
1: 5d pop %rbp
2: c3 ret
3: e8 72 5b d9 ff call 0xffd95b7a
8: be 02 00 00 00 mov $0x2,%esi
d: eb 0a jmp 0x19
f: e8 66 5b d9 ff call 0xffd95b7a
14: be 01 00 00 00 mov $0x1,%esi
19: 48 89 df mov %rbx,%rdi
1c: 5b pop %rbx
1d: 41 5e pop %r14
1f: 5d pop %rbp
20: e9 95 d6 83 02 jmp 0x283d6ba
25: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1)
* 2a: 55 push %rbp <-- trapping instruction
2b: 41 57 push %r15
2d: 41 56 push %r14
2f: 53 push %rbx
30: 48 89 fb mov %rdi,%rbx
33: e8 42 5b d9 ff call 0xffd95b7a
38: 4c 8d b3 2c 01 00 00 lea 0x12c(%rbx),%r14
3f: 4c rex.WR