================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6fa/0x960 kernel/bpf/stackmap.c:274 Write of size 184 at addr ffff88813102c390 by task syz.4.357/1635 CPU: 0 PID: 1635 Comm: syz.4.357 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_000f949dc4761d6a+0x28/0x3d 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:unwind_get_return_address+0x3b/0x90 arch/x86/kernel/unwind_frame.c:19 Code: 00 00 fc ff df 48 89 f8 48 c1 e8 03 42 0f b6 04 30 84 c0 75 48 83 3b 00 74 3a 48 83 c3 48 49 89 df 49 c1 ef 03 43 80 3c 37 00 <74> 08 48 89 df e8 5b 13 81 00 48 8b 3b e8 43 22 14 00 85 c0 74 14 RSP: 0018:ffffc900011872e0 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffffc90001187350 RCX: 0000000001187301 RDX: ffffc90001187988 RSI: 1ffff92000230e62 RDI: ffffc90001187308 RBP: ffffc900011872f8 R08: ffffc900011873d0 R09: ffffc900011873c8 R10: 0000000000000006 R11: fffff52000230e6d R12: ffff88810b31a880 R13: dffffc0000000000 R14: dffffc0000000000 R15: 1ffff92000230e6a arch_stack_walk+0xfc/0x150 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0xa6/0xf0 kernel/stacktrace.c:122 kasan_save_stack+0x3a/0x60 mm/kasan/common.c:46 __kasan_record_aux_stack+0xb6/0xc0 mm/kasan/generic.c:486 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:496 __call_rcu_common kernel/rcu/tree.c:2807 [inline] call_rcu+0xcf/0xf90 kernel/rcu/tree.c:2926 put_task_struct_rcu_user+0x5b/0x90 kernel/exit.c:233 finish_task_switch+0x346/0x7b0 kernel/sched/core.c:5338 context_switch kernel/sched/core.c:5428 [inline] __schedule+0xbae/0x1500 kernel/sched/core.c:6755 preempt_schedule_common+0x9b/0xf0 kernel/sched/core.c:6924 preempt_schedule+0xbc/0xd0 kernel/sched/core.c:6948 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34 try_to_wake_up+0x6b8/0x1220 kernel/sched/core.c:4400 wake_up_process kernel/sched/core.c:4528 [inline] wake_up_q+0xdc/0x1b0 kernel/sched/core.c:1032 futex_wake+0x5e9/0x8e0 kernel/futex/waitwake.c:188 do_futex+0x2bf/0x430 kernel/futex/syscalls.c:141 __do_sys_futex kernel/futex/syscalls.c:213 [inline] __se_sys_futex+0x136/0x310 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: 0033:0x7f243799c819 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:00007f24388b80e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 00007f2437c16098 RCX: 00007f243799c819 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f2437c1609c RBP: 00007f2437c16090 R08: 002f469c826ff82a R09: 0000000000000000 R10: 0000000000000012 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f2437c16128 R14: 00007ffc5f2d9e40 R15: 00007ffc5f2d9f28 Allocated by task 1635: 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 ffff88813102c380 which belongs to the cache kmalloc-64 of size 64 The buggy address is located 16 bytes inside of 64-byte region [ffff88813102c380, ffff88813102c3c0) The buggy address belongs to the physical page: page:ffffea0004c40b00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x13102c flags: 0x4000000000000200(slab|zone=1) raw: 4000000000000200 0000000000000000 dead000000000001 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 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 284, tgid 284 (syz-executor), ts 21370351360, free_ts 0 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_trace+0x29/0xb0 mm/slab_common.c:1028 kmalloc include/linux/slab.h:563 [inline] __kthread_create_on_node+0x144/0x580 kernel/kthread.c:431 kthread_create_on_node+0xe8/0x140 kernel/kthread.c:522 init_rescuer+0x1ab/0x2b0 kernel/workqueue.c:4287 alloc_workqueue+0xd0c/0x1220 kernel/workqueue.c:4362 wg_newlink+0x3b3/0x790 drivers/net/wireguard/device.c:347 rtnl_newlink_create net/core/rtnetlink.c:3422 [inline] __rtnl_newlink net/core/rtnetlink.c:3642 [inline] rtnl_newlink+0x1537/0x20b0 net/core/rtnetlink.c:3655 page_owner free stack trace missing Memory state around the buggy address: ffff88813102c280: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88813102c300: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc >ffff88813102c380: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc ^ ffff88813102c400: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88813102c480: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ================================================================== ---------------- Code disassembly (best guess): 0: 00 00 add %al,(%rax) 2: fc cld 3: ff lcall (bad) 4: df 48 89 fisttps -0x77(%rax) 7: f8 clc 8: 48 c1 e8 03 shr $0x3,%rax c: 42 0f b6 04 30 movzbl (%rax,%r14,1),%eax 11: 84 c0 test %al,%al 13: 75 48 jne 0x5d 15: 83 3b 00 cmpl $0x0,(%rbx) 18: 74 3a je 0x54 1a: 48 83 c3 48 add $0x48,%rbx 1e: 49 89 df mov %rbx,%r15 21: 49 c1 ef 03 shr $0x3,%r15 25: 43 80 3c 37 00 cmpb $0x0,(%r15,%r14,1) * 2a: 74 08 je 0x34 <-- trapping instruction 2c: 48 89 df mov %rbx,%rdi 2f: e8 5b 13 81 00 call 0x81138f 34: 48 8b 3b mov (%rbx),%rdi 37: e8 43 22 14 00 call 0x14227f 3c: 85 c0 test %eax,%eax 3e: 74 14 je 0x54