================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6fa/0x960 kernel/bpf/stackmap.c:274 Write of size 24 at addr ffff8881314fd4a8 by task syz.2.194/1091 CPU: 1 PID: 1091 Comm: syz.2.194 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/06/2026 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:377 [inline] bpf_get_stackid_pe+0x350/0x400 kernel/bpf/stackmap.c:334 bpf_prog_7c99200ca08d4ddc+0x2b/0x40 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+0x3c7/0x5e0 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:1689 [inline] __hrtimer_run_queues+0x398/0x8a0 kernel/time/hrtimer.c:1753 hrtimer_interrupt+0x3ad/0x8c0 kernel/time/hrtimer.c:1815 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+0x53/0xc0 arch/x86/kernel/apic/apic.c:1118 asm_sysvec_apic_timer_interrupt+0x1b/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0033:0x7f50209a8f19 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:00007f5021868028 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 00007f5020c25fa0 RCX: 00007f50209a8f19 RDX: 0000000000000005 RSI: 0000000040042408 RDI: 0000000000000003 RBP: 00007f5020a37f6d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f5020c26038 R14: 00007f5020c25fa0 R15: 00007ffc173d3278 Allocated by task 1094: 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 ffff8881314fd480 which belongs to the cache kmalloc-64 of size 64 The buggy address is located 40 bytes inside of 64-byte region [ffff8881314fd480, ffff8881314fd4c0) The buggy address belongs to the physical page: page:ffffea0004c53f40 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1314fd flags: 0x4000000000000200(slab|zone=1) raw: 4000000000000200 dead000000000100 dead000000000122 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 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 2, tgid 2 (kthreadd), ts 24777594685, free_ts 0 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f5/0x210 mm/page_alloc.c:2673 prep_new_page+0x1c/0x110 mm/page_alloc.c:2680 get_page_from_freelist+0x2ca9/0x2d20 mm/page_alloc.c:4587 __alloc_pages+0x1fa/0x610 mm/page_alloc.c:5931 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_node+0xa2/0x1e0 mm/slab_common.c:945 kmalloc_node include/linux/slab.h:589 [inline] __vmalloc_area_node mm/vmalloc.c:3070 [inline] __vmalloc_node_range+0x564/0x1440 mm/vmalloc.c:3256 alloc_thread_stack_node kernel/fork.c:322 [inline] dup_task_struct+0x3ca/0x900 kernel/fork.c:1086 copy_process+0x5e7/0x3500 kernel/fork.c:2315 kernel_clone+0x22f/0x7f0 kernel/fork.c:2903 kernel_thread+0x103/0x160 kernel/fork.c:2965 create_kthread kernel/kthread.c:409 [inline] kthreadd+0x346/0x480 kernel/kthread.c:760 page_owner free stack trace missing Memory state around the buggy address: ffff8881314fd380: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8881314fd400: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc >ffff8881314fd480: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc ^ ffff8881314fd500: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8881314fd580: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc ==================================================================