================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6fa/0x960 kernel/bpf/stackmap.c:274 Write of size 32 at addr ffff88811feed790 by task syz.4.157/851 CPU: 1 PID: 851 Comm: syz.4.157 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_63b2f832178674be+0x21/0x3a 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: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:__x64_sys_futex+0xa7/0x100 kernel/futex/syscalls.c:194 Code: 8d 7b 38 48 89 f8 48 c1 e8 03 42 80 3c 38 00 74 05 e8 8d b3 4f 00 4c 8b 6b 38 48 8d 7b 48 48 89 f8 48 c1 e8 03 42 80 3c 38 00 <74> 05 e8 72 b3 4f 00 4c 8b 73 48 48 83 c3 40 48 89 d8 48 c1 e8 03 RSP: 0018:ffffc9000eadfec8 EFLAGS: 00000246 RAX: 1ffff92001d5bff4 RBX: ffffc9000eadff58 RCX: 0000000000080000 RDX: ffffc90003371000 RSI: 000000000000003b RDI: ffffc9000eadffa0 RBP: ffffc9000eadff00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 00000000000f4240 R13: 0000000000000000 R14: ffffc9000eadff58 R15: dffffc0000000000 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: 0033:0x7fc493f9ce59 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:00007fc4929f70e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 00007fc494215fa8 RCX: 00007fc493f9ce59 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007fc494215fac RBP: 00007fc494215fa0 R08: 000a637a581f5168 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fc494216038 R14: 00007ffc574b02f0 R15: 00007ffc574b03d8 Allocated by task 851: 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 ffff88811feed780 which belongs to the cache kmalloc-64 of size 64 The buggy address is located 16 bytes inside of 64-byte region [ffff88811feed780, ffff88811feed7c0) The buggy address belongs to the physical page: page:ffffea00047fbb40 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11feed 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 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 291, tgid 291 (syz-executor), ts 28876507250, free_ts 28875295864 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 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+0x326/0x1440 mm/vmalloc.c:3216 __vmalloc_node mm/vmalloc.c:3321 [inline] vzalloc+0x78/0x90 mm/vmalloc.c:3394 alloc_counters+0x66/0x520 net/ipv4/netfilter/ip_tables.c:801 copy_entries_to_user net/ipv4/netfilter/ip_tables.c:823 [inline] get_entries net/ipv4/netfilter/ip_tables.c:1024 [inline] do_ipt_get_ctl+0xa7d/0x1190 net/ipv4/netfilter/ip_tables.c:1670 nf_getsockopt+0x27f/0x2a0 net/netfilter/nf_sockopt.c:116 page last free stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] free_pages_prepare mm/page_alloc.c:1580 [inline] free_pcp_prepare mm/page_alloc.c:1654 [inline] free_unref_page_prepare+0x80c/0x820 mm/page_alloc.c:3621 free_unref_page+0x93/0x530 mm/page_alloc.c:3719 free_the_page mm/page_alloc.c:863 [inline] __free_pages+0x67/0x100 mm/page_alloc.c:6020 __vunmap+0xa3c/0xc00 mm/vmalloc.c:2739 __vfree mm/vmalloc.c:2788 [inline] vfree+0x61/0x90 mm/vmalloc.c:2819 copy_entries_to_user net/ipv4/netfilter/arp_tables.c:713 [inline] get_entries net/ipv4/netfilter/arp_tables.c:867 [inline] do_arpt_get_ctl+0xd7b/0x1070 net/ipv4/netfilter/arp_tables.c:1461 nf_getsockopt+0x27f/0x2a0 net/netfilter/nf_sockopt.c:116 ip_getsockopt+0x157/0x1e0 net/ipv4/ip_sockglue.c:1826 tcp_getsockopt+0xff/0x130 net/ipv4/tcp.c:4463 sock_common_getsockopt+0xaa/0xc0 net/core/sock.c:3680 __sys_getsockopt+0x215/0x490 net/socket.c:2321 __do_sys_getsockopt net/socket.c:2336 [inline] __se_sys_getsockopt net/socket.c:2333 [inline] __x64_sys_getsockopt+0xbf/0xd0 net/socket.c:2333 x64_sys_call+0x3d/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:56 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: ffff88811feed680: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc ffff88811feed700: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc >ffff88811feed780: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc ^ ffff88811feed800: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88811feed880: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ================================================================== ---------------- Code disassembly (best guess): 0: 8d 7b 38 lea 0x38(%rbx),%edi 3: 48 89 f8 mov %rdi,%rax 6: 48 c1 e8 03 shr $0x3,%rax a: 42 80 3c 38 00 cmpb $0x0,(%rax,%r15,1) f: 74 05 je 0x16 11: e8 8d b3 4f 00 call 0x4fb3a3 16: 4c 8b 6b 38 mov 0x38(%rbx),%r13 1a: 48 8d 7b 48 lea 0x48(%rbx),%rdi 1e: 48 89 f8 mov %rdi,%rax 21: 48 c1 e8 03 shr $0x3,%rax 25: 42 80 3c 38 00 cmpb $0x0,(%rax,%r15,1) * 2a: 74 05 je 0x31 <-- trapping instruction 2c: e8 72 b3 4f 00 call 0x4fb3a3 31: 4c 8b 73 48 mov 0x48(%rbx),%r14 35: 48 83 c3 40 add $0x40,%rbx 39: 48 89 d8 mov %rbx,%rax 3c: 48 c1 e8 03 shr $0x3,%rax