================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6c7/0x900 kernel/bpf/stackmap.c:271 Write of size 24 at addr ffff88802f8a41a8 by task syz.0.17/5931 CPU: 0 PID: 5931 Comm: syz.0.17 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xa8/0x210 mm/kasan/report.c:468 kasan_report+0x117/0x150 mm/kasan/report.c:581 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x241/0x290 mm/kasan/generic.c:187 __asan_memcpy+0x40/0x70 mm/kasan/shadow.c:106 __bpf_get_stackid+0x6c7/0x900 kernel/bpf/stackmap.c:271 ____bpf_get_stackid_pe kernel/bpf/stackmap.c:374 [inline] bpf_get_stackid_pe+0x2f0/0x410 kernel/bpf/stackmap.c:331 bpf_prog_ee169d054574282b+0x2c/0x41 bpf_dispatcher_nop_func include/linux/bpf.h:1224 [inline] __bpf_prog_run include/linux/filter.h:617 [inline] bpf_prog_run include/linux/filter.h:624 [inline] bpf_overflow_handler+0x1fc/0x510 kernel/events/core.c:10584 __perf_event_overflow+0x461/0x660 kernel/events/core.c:9720 perf_event_overflow kernel/events/core.c:9741 [inline] perf_swevent_hrtimer+0x437/0x610 kernel/events/core.c:11230 __run_hrtimer kernel/time/hrtimer.c:1754 [inline] __hrtimer_run_queues+0x4e8/0xc10 kernel/time/hrtimer.c:1818 hrtimer_interrupt+0x39d/0x980 kernel/time/hrtimer.c:1880 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1077 [inline] __sysvec_apic_timer_interrupt+0xfb/0x3b0 arch/x86/kernel/apic/apic.c:1094 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0x51/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0033:0x7f7cc5b9e159 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:00007ffce9321c48 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 00007f7cc5e25fa0 RCX: 00007f7cc5b9e159 RDX: 0000000000000004 RSI: 0000000040042408 RDI: 0000000000000005 RBP: 00007f7cc5c3503b R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f7cc5e25fac R14: 00007f7cc5e25fa0 R15: 00007f7cc5e25fa0 Allocated by task 5931: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 ____kasan_kmalloc mm/kasan/common.c:375 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:384 kasan_kmalloc include/linux/kasan.h:198 [inline] __do_kmalloc_node mm/slab_common.c:1007 [inline] __kmalloc_node+0xb6/0x240 mm/slab_common.c:1014 kmalloc_node include/linux/slab.h:620 [inline] __bpf_map_area_alloc kernel/bpf/syscall.c:303 [inline] bpf_map_area_alloc+0x5e/0x110 kernel/bpf/syscall.c:316 prealloc_elems_and_freelist+0x86/0x1c0 kernel/bpf/stackmap.c:51 stack_map_alloc+0x32b/0x4b0 kernel/bpf/stackmap.c:114 map_create+0x877/0x12f0 kernel/bpf/syscall.c:1247 __sys_bpf+0x651/0x890 kernel/bpf/syscall.c:5460 __do_sys_bpf kernel/bpf/syscall.c:5582 [inline] __se_sys_bpf kernel/bpf/syscall.c:5580 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5580 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff88802f8a4180 which belongs to the cache kmalloc-cg-64 of size 64 The buggy address is located 40 bytes inside of allocated 48-byte region [ffff88802f8a4180, ffff88802f8a41b0) The buggy address belongs to the physical page: page:ffffea0000be2900 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2f8a4 memcg:ffff8880776f7201 flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff888017c4da00 dead000000000122 0000000000000000 raw: 0000000000000000 0000000080200020 00000001ffffffff ffff8880776f7201 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 5890, tgid 5890 (syz-executor), ts 90895144226, free_ts 90894854870 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1c1/0x200 mm/page_alloc.c:1582 prep_new_page mm/page_alloc.c:1589 [inline] get_page_from_freelist+0x2181/0x22a0 mm/page_alloc.c:3221 __alloc_pages+0x1f0/0x460 mm/page_alloc.c:4501 alloc_slab_page+0x5d/0x180 mm/slub.c:1881 allocate_slab mm/slub.c:2028 [inline] new_slab+0x87/0x2d0 mm/slub.c:2081 ___slab_alloc+0xc5c/0x12f0 mm/slub.c:3253 __slab_alloc mm/slub.c:3339 [inline] __slab_alloc_node mm/slub.c:3392 [inline] slab_alloc_node mm/slub.c:3485 [inline] __kmem_cache_alloc_node+0x11f/0x250 mm/slub.c:3534 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc_node+0xa6/0x240 mm/slab_common.c:1014 kmalloc_node include/linux/slab.h:620 [inline] kvmalloc_node+0x70/0x180 mm/util.c:617 kvmalloc include/linux/slab.h:738 [inline] kvzalloc include/linux/slab.h:746 [inline] allocate_hook_entries_size net/netfilter/core.c:61 [inline] nf_hook_entries_grow+0x27c/0x710 net/netfilter/core.c:140 nf_hook_entries_insert_raw+0x4b/0x300 net/netfilter/core.c:204 nf_nat_register_fn+0x1dd/0x540 net/netfilter/nf_nat_core.c:1274 ip6t_nat_register_lookups net/ipv6/netfilter/ip6table_nat.c:79 [inline] ip6table_nat_table_init+0x1a0/0x2c0 net/ipv6/netfilter/ip6table_nat.c:123 xt_find_table_lock+0x304/0x3e0 net/netfilter/x_tables.c:1282 xt_request_find_table_lock+0x26/0x100 net/netfilter/x_tables.c:1307 get_info net/ipv6/netfilter/ip6_tables.c:977 [inline] do_ip6t_get_ctl+0x71a/0x1220 net/ipv6/netfilter/ip6_tables.c:1665 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1182 [inline] free_unref_page_prepare+0x7d7/0x8f0 mm/page_alloc.c:2366 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2459 vfree+0x1a7/0x340 mm/vmalloc.c:2899 copy_entries_to_user net/ipv6/netfilter/ip6_tables.c:880 [inline] get_entries net/ipv6/netfilter/ip6_tables.c:1037 [inline] do_ip6t_get_ctl+0xf01/0x1220 net/ipv6/netfilter/ip6_tables.c:1674 nf_getsockopt+0x262/0x280 net/netfilter/nf_sockopt.c:116 ipv6_getsockopt+0x233/0x2e0 net/ipv6/ipv6_sockglue.c:1499 do_sock_getsockopt+0x379/0x450 net/socket.c:2384 __sys_getsockopt net/socket.c:2413 [inline] __do_sys_getsockopt net/socket.c:2423 [inline] __se_sys_getsockopt net/socket.c:2420 [inline] __x64_sys_getsockopt+0x1d6/0x280 net/socket.c:2420 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Memory state around the buggy address: ffff88802f8a4080: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc ffff88802f8a4100: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc >ffff88802f8a4180: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc ^ ffff88802f8a4200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88802f8a4280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================