================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6fa/0x960 kernel/bpf/stackmap.c:274 Write of size 56 at addr ffff888115995b90 by task syz.0.259/1314 CPU: 1 PID: 1314 Comm: syz.0.259 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 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_a448e89f4c9ad9d1+0x28/0x42 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+0x521/0x5e0 kernel/events/core.c:10273 __perf_event_overflow+0x458/0x640 kernel/events/core.c:9448 perf_event_overflow kernel/events/core.c:9469 [inline] perf_swevent_hrtimer+0x4b4/0x540 kernel/events/core.c:10919 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x398/0x890 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x3ad/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:__sanitizer_cov_trace_pc+0x45/0x60 kernel/kcov.c:221 Code: ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 6c 0b 00 00 00 74 2c 8b 91 48 0b 00 00 83 fa 02 75 21 48 8b 91 50 0b 00 00 48 8b 32 <48> 8d 7e 01 8b 89 4c 0b 00 00 48 39 cf 73 08 48 89 3a 48 89 44 f2 RSP: 0018:ffffc9000ecbfdb0 EFLAGS: 00000246 RAX: ffffffff81673cf8 RBX: 0000000000000000 RCX: ffff88811b4a2880 RDX: ffffc900011b9000 RSI: 0000000000000033 RDI: 0000000000000000 RBP: ffffc9000ecbfdb0 R08: ffffc9000ecbfe4f R09: ffffc9000ecbfe40 R10: dffffc0000000000 R11: fffff52001d97fca R12: 0000000000000081 R13: 1ffff92001d97fc0 R14: 0000000000000000 R15: ffffc9000ecbfe40 __do_sys_futex kernel/futex/syscalls.c:202 [inline] __se_sys_futex+0x108/0x310 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: 0033:0x7f1beaf9ce59 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:00007f1bebf4c0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 00007f1beb215fa8 RCX: 00007f1beaf9ce59 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f1beb215fac RBP: 00007f1beb215fa0 R08: 001e9f7dc09f2a36 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f1beb216038 R14: 00007ffcc8d79920 R15: 00007ffcc8d79a08 Allocated by task 1314: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 kasan_save_alloc_info+0x1f/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+0x398/0x520 kernel/bpf/stackmap.c:117 find_and_alloc_map kernel/bpf/syscall.c:133 [inline] map_create+0x467/0xcf0 kernel/bpf/syscall.c:1126 __sys_bpf+0x34e/0x850 kernel/bpf/syscall.c:4988 __do_sys_bpf kernel/bpf/syscall.c:5110 [inline] __se_sys_bpf kernel/bpf/syscall.c:5108 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5108 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 ffff888115995b80 which belongs to the cache kmalloc-64 of size 64 The buggy address is located 16 bytes inside of 64-byte region [ffff888115995b80, ffff888115995bc0) The buggy address belongs to the physical page: page:ffffea0004566540 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x115995 flags: 0x4000000000000200(slab|zone=1) raw: 4000000000000200 ffffea0004cee540 dead000000000006 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 0x16cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_RETRY_MAYFAIL|__GFP_NORETRY), pid 108, tgid 108 (udevd), ts 5546502248, free_ts 0 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f5/0x210 mm/page_alloc.c:2672 prep_new_page+0x1c/0x110 mm/page_alloc.c:2679 get_page_from_freelist+0x2ca9/0x2d20 mm/page_alloc.c:4586 __alloc_pages+0x1fa/0x610 mm/page_alloc.c:5930 alloc_slab_page+0x6e/0xf0 include/linux/gfp.h:-1 allocate_slab mm/slub.c:1967 [inline] new_slab+0x98/0x3e0 mm/slub.c:2020 ___slab_alloc+0x70f/0xb70 mm/slub.c:3177 __slab_alloc+0x5e/0xa0 mm/slub.c:3263 slab_alloc_node mm/slub.c:3348 [inline] __kmem_cache_alloc_node+0x204/0x2d0 mm/slub.c:3423 __do_kmalloc_node mm/slab_common.c:937 [inline] __kmalloc+0xa4/0x1e0 mm/slab_common.c:951 kmalloc include/linux/slab.h:568 [inline] inotify_handle_inode_event+0x18f/0x4e0 fs/notify/inotify/inotify_fsnotify.c:96 fsnotify_handle_inode_event fs/notify/fsnotify.c:282 [inline] fsnotify_handle_event fs/notify/fsnotify.c:311 [inline] send_to_group fs/notify/fsnotify.c:385 [inline] fsnotify+0x1992/0x1fa0 fs/notify/fsnotify.c:591 __fsnotify_parent+0x683/0x820 fs/notify/fsnotify.c:248 fsnotify_parent include/linux/fsnotify.h:77 [inline] fsnotify_dentry include/linux/fsnotify.h:89 [inline] fsnotify_change+0x210/0x280 include/linux/fsnotify.h:410 notify_change+0xd7d/0x1030 fs/attr.c:504 vfs_utimes+0x416/0x5b0 fs/utimes.c:65 page_owner free stack trace missing Memory state around the buggy address: ffff888115995a80: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff888115995b00: 00 00 00 00 00 00 00 02 fc fc fc fc fc fc fc fc >ffff888115995b80: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc ^ ffff888115995c00: 00 00 00 00 00 00 00 07 fc fc fc fc fc fc fc fc ffff888115995c80: 00 00 00 00 00 00 00 03 fc fc fc fc fc fc fc fc ================================================================== ---------------- Code disassembly (best guess): 0: ff 00 incl (%rax) 2: 74 11 je 0x15 4: 81 fa 00 01 00 00 cmp $0x100,%edx a: 75 35 jne 0x41 c: 83 b9 6c 0b 00 00 00 cmpl $0x0,0xb6c(%rcx) 13: 74 2c je 0x41 15: 8b 91 48 0b 00 00 mov 0xb48(%rcx),%edx 1b: 83 fa 02 cmp $0x2,%edx 1e: 75 21 jne 0x41 20: 48 8b 91 50 0b 00 00 mov 0xb50(%rcx),%rdx 27: 48 8b 32 mov (%rdx),%rsi * 2a: 48 8d 7e 01 lea 0x1(%rsi),%rdi <-- trapping instruction 2e: 8b 89 4c 0b 00 00 mov 0xb4c(%rcx),%ecx 34: 48 39 cf cmp %rcx,%rdi 37: 73 08 jae 0x41 39: 48 89 3a mov %rdi,(%rdx) 3c: 48 rex.W 3d: 89 .byte 0x89 3e: 44 rex.R 3f: f2 repnz