================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6c9/0x920 kernel/bpf/stackmap.c:274 Write of size 48 at addr ffff88802d864290 by task syz.3.2456/13082 CPU: 1 PID: 13082 Comm: syz.3.2456 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 print_address_description mm/kasan/report.c:316 [inline] print_report+0xa8/0x210 mm/kasan/report.c:420 kasan_report+0x10b/0x140 mm/kasan/report.c:524 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x235/0x290 mm/kasan/generic.c:189 memcpy+0x3c/0x60 mm/kasan/shadow.c:66 __bpf_get_stackid+0x6c9/0x920 kernel/bpf/stackmap.c:274 ____bpf_get_stackid_pe kernel/bpf/stackmap.c:365 [inline] bpf_get_stackid_pe+0x33f/0x400 kernel/bpf/stackmap.c:334 bpf_prog_ee9fdca00c0e1e15+0x28/0x3d bpf_dispatcher_nop_func include/linux/bpf.h:1012 [inline] __bpf_prog_run include/linux/filter.h:607 [inline] bpf_prog_run include/linux/filter.h:614 [inline] bpf_overflow_handler+0x50b/0x790 kernel/events/core.c:10321 __perf_event_overflow+0x457/0x630 kernel/events/core.c:9496 perf_swevent_overflow kernel/events/core.c:9579 [inline] perf_swevent_event+0x315/0x570 kernel/events/core.c:9630 do_perf_sw_event kernel/events/core.c:9743 [inline] ___perf_sw_event+0x498/0x6d0 kernel/events/core.c:9774 __perf_sw_event+0x135/0x260 kernel/events/core.c:9786 perf_sw_event include/linux/perf_event.h:1254 [inline] do_user_addr_fault+0x497/0xb20 arch/x86/mm/fault.c:1284 handle_page_fault arch/x86/mm/fault.c:1429 [inline] exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1482 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0010:__get_user_4+0x1c/0x30 arch/x86/lib/getuser.S:85 Code: 01 ca c3 90 90 90 90 90 90 90 90 90 90 90 48 ba fd ef ff ff ff 7f 00 00 48 39 d0 0f 83 90 00 00 00 48 19 d2 48 21 d0 0f 01 cb <8b> 10 31 c0 0f 01 ca c3 90 90 90 90 90 90 90 90 90 90 90 90 48 ba RSP: 0018:ffffc9000471fd48 EFLAGS: 00050202 RAX: 0000000000000004 RBX: ffffc9000471fe20 RCX: 32bd35015e9d8400 RDX: ffffffffffffffff RSI: ffffffff8a8c2920 RDI: ffffffff8adf5de0 RBP: ffffc9000471ff10 R08: ffffffff8e210aef R09: 1ffffffff1c4215d R10: dffffc0000000000 R11: fffffbfff1c4215e R12: 0000000000000000 R13: 0000000000000004 R14: dffffc0000000000 R15: 0000000000000000 perf_copy_attr+0x45/0x840 kernel/events/core.c:12099 __do_sys_perf_event_open kernel/events/core.c:12440 [inline] __se_sys_perf_event_open+0xf5/0x1ec0 kernel/events/core.c:12418 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: 0033:0x7fe20ff9e0d9 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:00007fe210f05028 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: ffffffffffffffda RBX: 00007fe210225fa0 RCX: 00007fe20ff9e0d9 RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007fe210035024 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000 R13: 00007fe210226038 R14: 00007fe210225fa0 R15: 00007ffe314c0e38 Allocated by task 13082: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 ____kasan_kmalloc mm/kasan/common.c:375 [inline] __kasan_kmalloc+0x8e/0xa0 mm/kasan/common.c:384 kasan_kmalloc include/linux/kasan.h:211 [inline] __do_kmalloc_node mm/slab_common.c:936 [inline] __kmalloc_node+0xb2/0x240 mm/slab_common.c:943 kmalloc_node include/linux/slab.h:589 [inline] __bpf_map_area_alloc kernel/bpf/syscall.c:328 [inline] bpf_map_area_alloc+0x47/0xe0 kernel/bpf/syscall.c:341 prealloc_elems_and_freelist+0x86/0x1c0 kernel/bpf/stackmap.c:51 stack_map_alloc+0x386/0x510 kernel/bpf/stackmap.c:117 find_and_alloc_map kernel/bpf/syscall.c:133 [inline] map_create+0x524/0xff0 kernel/bpf/syscall.c:1149 __sys_bpf+0x38b/0x780 kernel/bpf/syscall.c:5014 __do_sys_bpf kernel/bpf/syscall.c:5136 [inline] __se_sys_bpf kernel/bpf/syscall.c:5134 [inline] __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5134 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 Last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:46 __kasan_record_aux_stack+0xb2/0xc0 mm/kasan/generic.c:486 call_rcu+0x14f/0x950 kernel/rcu/tree.c:2849 nf_unregister_net_hook net/netfilter/core.c:-1 [inline] nf_unregister_net_hooks+0xc7/0x130 net/netfilter/core.c:601 nf_ct_netns_do_put net/netfilter/nf_conntrack_proto.c:568 [inline] nf_ct_netns_put+0x369/0x510 net/netfilter/nf_conntrack_proto.c:-1 nf_conncount_destroy+0x3d/0x150 net/netfilter/nf_conncount.c:687 ovs_ct_limit_exit net/openvswitch/conntrack.c:1919 [inline] ovs_ct_exit+0x98/0x200 net/openvswitch/conntrack.c:2322 ovs_exit_net+0xe9/0x7a0 net/openvswitch/datapath.c:2687 ops_exit_list net/core/net_namespace.c:172 [inline] cleanup_net+0x703/0xba0 net/core/net_namespace.c:640 process_one_work+0x8ab/0x1160 kernel/workqueue.c:2292 worker_thread+0xaf5/0x12a0 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Second to last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:46 __kasan_record_aux_stack+0xb2/0xc0 mm/kasan/generic.c:486 call_rcu+0x14f/0x950 kernel/rcu/tree.c:2849 nf_unregister_net_hook net/netfilter/core.c:-1 [inline] nf_unregister_net_hooks+0xc7/0x130 net/netfilter/core.c:601 ops_exit_list net/core/net_namespace.c:172 [inline] cleanup_net+0x703/0xba0 net/core/net_namespace.c:640 process_one_work+0x8ab/0x1160 kernel/workqueue.c:2292 worker_thread+0xaf5/0x12a0 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 The buggy address belongs to the object at ffff88802d864280 which belongs to the cache kmalloc-cg-64 of size 64 The buggy address is located 16 bytes inside of 64-byte region [ffff88802d864280, ffff88802d8642c0) The buggy address belongs to the physical page: page:ffffea0000b61900 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88802d864f00 pfn:0x2d864 memcg:ffff888028e7dc01 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 ffffea0001f9fc80 dead000000000002 ffff888017442780 raw: ffff88802d864f00 000000008020001f 00000001ffffffff ffff888028e7dc01 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 4288, tgid 4288 (syz-executor), ts 89332744918, free_ts 89323419341 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2560 prep_new_page mm/page_alloc.c:2567 [inline] get_page_from_freelist+0x206b/0x2180 mm/page_alloc.c:4358 __alloc_pages+0x1ec/0x4f0 mm/page_alloc.c:5658 alloc_slab_page+0x5d/0x180 mm/slub.c:1799 allocate_slab mm/slub.c:1944 [inline] new_slab+0x87/0x2d0 mm/slub.c:1997 ___slab_alloc+0xbc5/0x1240 mm/slub.c:3154 __slab_alloc mm/slub.c:3240 [inline] slab_alloc_node mm/slub.c:3325 [inline] __kmem_cache_alloc_node+0x126/0x270 mm/slub.c:3398 __do_kmalloc_node mm/slab_common.c:935 [inline] __kmalloc_node+0xa2/0x240 mm/slab_common.c:943 kmalloc_node include/linux/slab.h:589 [inline] kvmalloc_node+0x6c/0x180 mm/util.c:581 kvmalloc include/linux/slab.h:716 [inline] kvzalloc include/linux/slab.h:724 [inline] allocate_hook_entries_size net/netfilter/core.c:61 [inline] nf_hook_entries_grow+0x31a/0x760 net/netfilter/core.c:128 nf_hook_entries_insert_raw+0x47/0x300 net/netfilter/core.c:192 nf_nat_register_fn+0x1d9/0x540 net/netfilter/nf_nat_core.c:1068 ip6t_nat_register_lookups net/ipv6/netfilter/ip6table_nat.c:79 [inline] ip6table_nat_table_init+0x19c/0x2c0 net/ipv6/netfilter/ip6table_nat.c:123 xt_find_table_lock+0x220/0x360 net/netfilter/x_tables.c:1282 xt_request_find_table_lock+0x22/0x100 net/netfilter/x_tables.c:1307 get_info net/ipv6/netfilter/ip6_tables.c:979 [inline] do_ip6t_get_ctl+0x5e8/0x11c0 net/ipv6/netfilter/ip6_tables.c:1667 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1487 [inline] free_pcp_prepare mm/page_alloc.c:1537 [inline] free_unref_page_prepare+0x8e5/0x9e0 mm/page_alloc.c:3414 free_unref_page_list+0xbb/0x8e0 mm/page_alloc.c:3555 release_pages+0x20d1/0x2340 mm/swap.c:1035 tlb_batch_pages_flush mm/mmu_gather.c:60 [inline] tlb_flush_mmu_free mm/mmu_gather.c:255 [inline] tlb_flush_mmu+0x105/0x220 mm/mmu_gather.c:262 tlb_finish_mmu+0xf0/0x220 mm/mmu_gather.c:394 exit_mmap+0x388/0x970 mm/mmap.c:3262 __mmput+0x118/0x3a0 kernel/fork.c:1206 exit_mm+0x24d/0x350 kernel/exit.c:572 do_exit+0x958/0x2570 kernel/exit.c:874 do_group_exit+0x229/0x2e0 kernel/exit.c:1030 get_signal+0x1259/0x1340 kernel/signal.c:2880 arch_do_signal_or_restart+0xc4/0x1310 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303 ret_from_fork+0x15/0x30 arch/x86/entry/entry_64.S:288 Memory state around the buggy address: ffff88802d864180: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88802d864200: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc >ffff88802d864280: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc ^ ffff88802d864300: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88802d864380: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ================================================================== ---------------- Code disassembly (best guess): 0: 01 ca add %ecx,%edx 2: c3 ret 3: 90 nop 4: 90 nop 5: 90 nop 6: 90 nop 7: 90 nop 8: 90 nop 9: 90 nop a: 90 nop b: 90 nop c: 90 nop d: 90 nop e: 48 ba fd ef ff ff ff movabs $0x7fffffffeffd,%rdx 15: 7f 00 00 18: 48 39 d0 cmp %rdx,%rax 1b: 0f 83 90 00 00 00 jae 0xb1 21: 48 19 d2 sbb %rdx,%rdx 24: 48 21 d0 and %rdx,%rax 27: 0f 01 cb stac * 2a: 8b 10 mov (%rax),%edx <-- trapping instruction 2c: 31 c0 xor %eax,%eax 2e: 0f 01 ca clac 31: c3 ret 32: 90 nop 33: 90 nop 34: 90 nop 35: 90 nop 36: 90 nop 37: 90 nop 38: 90 nop 39: 90 nop 3a: 90 nop 3b: 90 nop 3c: 90 nop 3d: 90 nop 3e: 48 rex.W 3f: ba .byte 0xba