================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6fa/0x960 kernel/bpf/stackmap.c:274 Write of size 56 at addr ffff88812e452810 by task syz.2.219/1089 CPU: 0 PID: 1089 Comm: syz.2.219 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_709c33675fcd9051+0x21/0x36 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:put_ctx+0x0/0x1a0 kernel/events/core.c:1212 Code: 86 a7 da ff be 02 00 00 00 eb 0a e8 7a a7 da ff be 01 00 00 00 48 89 df e8 3d b8 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 4d a7 da ff 4c 8d b3 RSP: 0018:ffffc90008e17bd8 EFLAGS: 00000246 RAX: f6d60faf6b6c7700 RBX: ffff8881102b9800 RCX: 0000000000000000 RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff8881102b9800 RBP: ffffc90008e17e80 R08: ffffc90008e17b67 R09: 1ffff920011c2f6c R10: dffffc0000000000 R11: fffff520011c2f6d R12: 0000000040042408 R13: dffffc0000000000 R14: fffff520011c2f8c 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: 0033:0x7f7e2679c819 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:00007f7e27737028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f7e26a15fa0 RCX: 00007f7e2679c819 RDX: 0000000000000004 RSI: 0000000040042408 RDI: 0000000000000005 RBP: 00007f7e26832c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f7e26a16038 R14: 00007f7e26a15fa0 R15: 00007ffe193ba5b8 Allocated by task 1089: 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 ffff88812e452800 which belongs to the cache kmalloc-64 of size 64 The buggy address is located 16 bytes inside of 64-byte region [ffff88812e452800, ffff88812e452840) The buggy address belongs to the physical page: page:ffffea0004b91480 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x12e452 flags: 0x4000000000000200(slab|zone=1) raw: 4000000000000200 ffffea0004ba3d40 dead000000000005 ffff888100042780 raw: 0000000000000000 0000000080200020 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 570, tgid 546 (syz.1.69), ts 31359064388, free_ts 31357750730 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_node_trace+0x26/0xb0 mm/slab_common.c:1041 kmalloc_node include/linux/slab.h:585 [inline] kzalloc_node include/linux/slab.h:710 [inline] __get_vm_area_node+0x12c/0x360 mm/vmalloc.c:2515 __vmalloc_node_range+0x326/0x1430 mm/vmalloc.c:3216 __vmalloc_node mm/vmalloc.c:3321 [inline] vmalloc+0x78/0x90 mm/vmalloc.c:3354 bpf_prog_calc_tag+0xf5/0x670 kernel/bpf/core.c:287 resolve_pseudo_ldimm64+0xd3/0x1190 kernel/bpf/verifier.c:13021 bpf_check+0x3e06/0x10d10 kernel/bpf/verifier.c:15555 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_pages+0x82/0x90 mm/page_alloc.c:6025 tlb_batch_list_free mm/mmu_gather.c:75 [inline] tlb_finish_mmu+0x2c7/0x370 mm/mmu_gather.c:364 exit_mmap+0x412/0xc10 mm/mmap.c:3384 __mmput+0x93/0x360 kernel/fork.c:1312 mmput+0x4b/0x150 kernel/fork.c:1336 exit_mm kernel/exit.c:568 [inline] do_exit+0x994/0x2660 kernel/exit.c:873 do_group_exit+0x210/0x2d0 kernel/exit.c:1028 get_signal+0x13b5/0x1520 kernel/signal.c:2891 arch_do_signal_or_restart+0xd1/0x1140 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x7a/0xb0 kernel/entry/common.c:174 exit_to_user_mode_prepare+0x87/0xd0 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:303 ret_from_fork+0x15/0x30 arch/x86/entry/entry_64.S:288 Memory state around the buggy address: ffff88812e452700: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88812e452780: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc >ffff88812e452800: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc ^ ffff88812e452880: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88812e452900: fa fb fb fb fb fb fb fb 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 7a a7 da ff call 0xffdaa786 c: be 01 00 00 00 mov $0x1,%esi 11: 48 89 df mov %rbx,%rdi 14: e8 3d b8 d1 00 call 0xd1b856 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 4d a7 da ff call 0xffdaa786 39: 4c rex.WR 3a: 8d .byte 0x8d 3b: b3 .byte 0xb3