==================================================================
BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6fa/0x960 kernel/bpf/stackmap.c:274
Write of size 56 at addr ffff888133f80890 by task syz.2.78/616

CPU: 0 PID: 616 Comm: syz.2.78 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
Call Trace:
 <IRQ>
 __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_88b6ce719581ac33+0x21/0x31
 bpf_dispatcher_nop_func include/linux/bpf.h:987 [inline]
 __bpf_prog_run include/linux/filter.h:596 [inline]
 bpf_prog_run include/linux/filter.h:614 [inline]
 bpf_overflow_handler+0x51f/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+0x3d5/0xa00 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
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1b/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:put_ctx+0x0/0x1a0 kernel/events/core.c:1212
Code: 46 a8 da ff be 02 00 00 00 eb 0a e8 3a a8 da ff be 01 00 00 00 48 89 df e8 4d 6a d1 00 eb d9 66 2e 0f 1f 84 00 00 00 00 00 90 <55> 48 89 e5 41 57 41 56 41 54 53 48 89 fb e8 0d a8 da ff 4c 8d b3
RSP: 0018:ffffc90000757bd8 EFLAGS: 00000246
RAX: 471a56f376de6200 RBX: ffff88811b518400 RCX: 0000000000000000
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff88811b518400
RBP: ffffc90000757e80 R08: ffffc90000757b67 R09: 1ffff920000eaf6c
R10: dffffc0000000000 R11: fffff520000eaf6d R12: 0000000040042408
R13: dffffc0000000000 R14: fffff520000eaf8c R15: 0000000000000000
 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: 0033:0x7fc58059aeb9
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:00007fc581435028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fc580815fa0 RCX: 00007fc58059aeb9
RDX: 0000000000000009 RSI: 0000000040042408 RDI: 000000000000000a
RBP: 00007fc580608c1f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc580816038 R14: 00007fc580815fa0 R15: 00007ffcae982428
 </TASK>

Allocated by task 616:
 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 ffff888133f80880
 which belongs to the cache kmalloc-64 of size 64
The buggy address is located 16 bytes inside of
 64-byte region [ffff888133f80880, ffff888133f808c0)

The buggy address belongs to the physical page:
page:ffffea0004cfe000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x133f80
flags: 0x4000000000000200(slab|zone=1)
raw: 4000000000000200 0000000000000000 dead000000000122 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 490, tgid 490 (udevd), ts 37469004183, free_ts 37461423078
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0x1f5/0x210 mm/page_alloc.c:2643
 prep_new_page+0x1c/0x110 mm/page_alloc.c:2650
 get_page_from_freelist+0x2d12/0x2d80 mm/page_alloc.c:4554
 __alloc_pages+0x1d9/0x480 mm/page_alloc.c:5868
 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 fs/xattr.c:1008 [inline]
 simple_xattr_set+0xbd/0x560 fs/xattr.c:1072
 shmem_xattr_handler_set+0x47/0xf0 mm/shmem.c:3341
 __vfs_setxattr+0x3f2/0x440 fs/xattr.c:182
 __vfs_setxattr_noperm+0x12a/0x5e0 fs/xattr.c:216
 __vfs_setxattr_locked+0x212/0x230 fs/xattr.c:277
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:26 [inline]
 free_pages_prepare mm/page_alloc.c:1551 [inline]
 free_pcp_prepare mm/page_alloc.c:1625 [inline]
 free_unref_page_prepare+0x742/0x750 mm/page_alloc.c:3589
 free_unref_page_list+0x117/0x8c0 mm/page_alloc.c:3740
 release_pages+0xaf2/0xb50 mm/swap.c:1048
 free_pages_and_swap_cache+0x86/0xa0 mm/swap_state.c:315
 tlb_batch_pages_flush mm/mmu_gather.c:59 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:254 [inline]
 tlb_flush_mmu mm/mmu_gather.c:261 [inline]
 tlb_finish_mmu+0x1aa/0x370 mm/mmu_gather.c:361
 exit_mmap+0x412/0xc10 mm/mmap.c:3384
 __mmput+0x93/0x360 kernel/fork.c:1309
 mmput+0x4b/0x150 kernel/fork.c:1333
 exit_mm kernel/exit.c:568 [inline]
 do_exit+0x994/0x2660 kernel/exit.c:873
 do_group_exit+0x210/0x2d0 kernel/exit.c:1028
 __do_sys_exit_group kernel/exit.c:1039 [inline]
 __se_sys_exit_group kernel/exit.c:1037 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1037
 x64_sys_call+0x7b4/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:232
 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

Memory state around the buggy address:
 ffff888133f80780: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff888133f80800: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
>ffff888133f80880: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
                                  ^
 ffff888133f80900: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff888133f80980: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc
==================================================================
----------------
Code disassembly (best guess), 4 bytes skipped:
   0:	be 02 00 00 00       	mov    $0x2,%esi
   5:	eb 0a                	jmp    0x11
   7:	e8 3a a8 da ff       	call   0xffdaa846
   c:	be 01 00 00 00       	mov    $0x1,%esi
  11:	48 89 df             	mov    %rbx,%rdi
  14:	e8 4d 6a d1 00       	call   0xd16a66
  19:	eb d9                	jmp    0xfffffff4
  1b:	66 2e 0f 1f 84 00 00 	cs nopw 0x0(%rax,%rax,1)
  22:	00 00 00
  25:	90                   	nop
* 26:	55                   	push   %rbp <-- trapping instruction
  27:	48 89 e5             	mov    %rsp,%rbp
  2a:	41 57                	push   %r15
  2c:	41 56                	push   %r14
  2e:	41 54                	push   %r12
  30:	53                   	push   %rbx
  31:	48 89 fb             	mov    %rdi,%rbx
  34:	e8 0d a8 da ff       	call   0xffdaa846
  39:	4c                   	rex.WR
  3a:	8d                   	.byte 0x8d
  3b:	b3                   	.byte 0xb3