================================================================== BUG: KASAN: use-after-free in __nft_trace_packet+0x135/0x150 net/netfilter/nf_tables_core.c:30 Read of size 2 at addr ffff88805f3826c0 by task syz-executor/8652 CPU: 0 PID: 8652 Comm: syz-executor Not tainted 5.15.189-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 print_address_description+0x60/0x2d0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0xdf/0x130 mm/kasan/report.c:451 __nft_trace_packet+0x135/0x150 net/netfilter/nf_tables_core.c:30 nft_trace_verdict net/netfilter/nf_tables_core.c:110 [inline] nft_do_chain+0x120e/0x1420 net/netfilter/nf_tables_core.c:256 nft_do_chain_inet+0x22b/0x300 net/netfilter/nft_chain_filter.c:161 nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline] nf_hook_slow+0xb9/0x200 net/netfilter/core.c:584 nf_hook include/linux/netfilter.h:257 [inline] NF_HOOK+0x1cb/0x360 include/linux/netfilter.h:300 NF_HOOK+0x2d6/0x360 include/linux/netfilter.h:302 __netif_receive_skb_one_core net/core/dev.c:5525 [inline] __netif_receive_skb+0xcc/0x290 net/core/dev.c:5639 process_backlog+0x364/0x780 net/core/dev.c:6516 __napi_poll+0xc0/0x430 net/core/dev.c:7075 napi_poll net/core/dev.c:7142 [inline] net_rx_action+0x4a8/0x9c0 net/core/dev.c:7232 handle_softirqs+0x328/0x820 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x12f/0x220 kernel/softirq.c:659 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671 instr_sysvec_call_function_single arch/x86/kernel/smp.c:243 [inline] sysvec_call_function_single+0x9d/0xc0 arch/x86/kernel/smp.c:243 asm_sysvec_call_function_single+0x16/0x20 arch/x86/include/asm/idtentry.h:684 RIP: 0010:check_preemption_disabled+0x18/0x110 lib/smp_processor_id.c:14 Code: 00 cc 48 c7 c7 e0 92 59 8a 48 c7 c6 20 93 59 8a eb 00 55 41 57 41 56 53 48 83 ec 10 65 48 8b 04 25 28 00 00 00 48 89 44 24 08 <65> 8b 05 a9 d7 59 76 65 8b 0d 12 32 5a 76 f7 c1 ff ff ff 7f 74 1f RSP: 0000:ffffc90004be7828 EFLAGS: 00000286 RAX: c2044c799b3b0600 RBX: 0000000000000000 RCX: ffffffff815bf63b RDX: 0000000000000000 RSI: ffffffff8a599320 RDI: ffffffff8a5992e0 RBP: ffffc90004be79a0 R08: dffffc0000000000 R09: fffffbfff1ad2dd6 R10: fffffbfff1ad2dd6 R11: 1ffffffff1ad2dd5 R12: ffffffff8c11c360 R13: 1ffff9200097cf1c R14: 0000000000000000 R15: dffffc0000000000 rcu_dynticks_curr_cpu_in_eqs kernel/rcu/tree.c:331 [inline] rcu_is_watching+0x11/0xa0 kernel/rcu/tree.c:1123 trace_lock_acquire include/trace/events/lock.h:13 [inline] lock_acquire+0xcd/0x3f0 kernel/locking/lockdep.c:5594 rcu_lock_acquire+0x20/0x30 include/linux/rcupdate.h:312 rcu_read_lock include/linux/rcupdate.h:739 [inline] lock_page_memcg+0xa9/0x410 mm/memcontrol.c:2047 page_add_file_rmap+0x185/0x940 mm/rmap.c:1219 do_set_pte+0x3c9/0x530 mm/memory.c:4069 filemap_map_pages+0xe7e/0x1390 mm/filemap.c:3344 do_fault_around mm/memory.c:4243 [inline] do_read_fault mm/memory.c:4258 [inline] do_fault mm/memory.c:4392 [inline] handle_pte_fault mm/memory.c:4650 [inline] __handle_mm_fault mm/memory.c:4785 [inline] handle_mm_fault+0x2580/0x43c0 mm/memory.c:4883 do_user_addr_fault+0x489/0xc80 arch/x86/mm/fault.c:1357 handle_page_fault arch/x86/mm/fault.c:1445 [inline] exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1501 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606 RIP: 0033:0x7effcc8f969f Code: 00 00 00 0f 1f 84 00 00 00 00 00 c5 f9 6e c6 89 f8 25 ff 0f 00 00 c4 e2 7d 78 c0 c5 f1 ef c9 3d e0 0f 00 00 0f 87 91 01 00 00 fe 6f 17 c5 fd 74 da c5 f5 74 d2 c5 ed eb db c5 fd d7 c3 85 c0 RSP: 002b:00007ffe7e9be688 EFLAGS: 00010283 RAX: 0000000000000566 RBX: 00007ffe7e9bebf0 RCX: 0000000000000000 RDX: 00007ffe7e9bed70 RSI: 0000000000000025 RDI: 00007effcc9aa566 RBP: 00000000fbad8001 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007effcc9aa566 R13: 00007ffe7e9bed70 R14: 0000000000000000 R15: 00007ffe7e9bebf0 Allocated by task 14: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] __kasan_slab_alloc+0x9c/0xd0 mm/kasan/common.c:467 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519 slab_alloc_node mm/slub.c:3220 [inline] kmem_cache_alloc_node+0x12d/0x2d0 mm/slub.c:3256 __alloc_skb+0xf4/0x750 net/core/skbuff.c:415 alloc_skb include/linux/skbuff.h:1162 [inline] synproxy_send_client_synack+0x169/0xdd0 net/netfilter/nf_synproxy_core.c:482 nft_synproxy_eval_v4+0x36b/0x560 net/netfilter/nft_synproxy.c:59 nft_synproxy_do_eval+0x341/0x570 net/netfilter/nft_synproxy.c:141 expr_call_ops_eval net/netfilter/nf_tables_core.c:198 [inline] nft_do_chain+0x3fc/0x1420 net/netfilter/nf_tables_core.c:238 nft_do_chain_inet+0x22b/0x300 net/netfilter/nft_chain_filter.c:161 nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline] nf_hook_slow+0xb9/0x200 net/netfilter/core.c:584 nf_hook include/linux/netfilter.h:257 [inline] NF_HOOK+0x1cb/0x360 include/linux/netfilter.h:300 NF_HOOK+0x2d6/0x360 include/linux/netfilter.h:302 __netif_receive_skb_one_core net/core/dev.c:5525 [inline] __netif_receive_skb+0xcc/0x290 net/core/dev.c:5639 process_backlog+0x364/0x780 net/core/dev.c:6516 __napi_poll+0xc0/0x430 net/core/dev.c:7075 napi_poll net/core/dev.c:7142 [inline] net_rx_action+0x4a8/0x9c0 net/core/dev.c:7232 handle_softirqs+0x328/0x820 kernel/softirq.c:576 run_ksoftirqd+0x98/0xf0 kernel/softirq.c:943 smpboot_thread_fn+0x4f6/0x970 kernel/smpboot.c:164 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Freed by task 8652: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:46 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360 ____kasan_slab_free+0xd5/0x110 mm/kasan/common.c:366 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1705 [inline] slab_free_freelist_hook+0xea/0x170 mm/slub.c:1731 slab_free mm/slub.c:3499 [inline] kmem_cache_free+0x8f/0x210 mm/slub.c:3515 nft_synproxy_eval_v4+0x373/0x560 net/netfilter/nft_synproxy.c:60 nft_synproxy_do_eval+0x341/0x570 net/netfilter/nft_synproxy.c:141 expr_call_ops_eval net/netfilter/nf_tables_core.c:198 [inline] nft_do_chain+0x3fc/0x1420 net/netfilter/nf_tables_core.c:238 nft_do_chain_inet+0x22b/0x300 net/netfilter/nft_chain_filter.c:161 nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline] nf_hook_slow+0xb9/0x200 net/netfilter/core.c:584 nf_hook include/linux/netfilter.h:257 [inline] NF_HOOK+0x1cb/0x360 include/linux/netfilter.h:300 NF_HOOK+0x2d6/0x360 include/linux/netfilter.h:302 __netif_receive_skb_one_core net/core/dev.c:5525 [inline] __netif_receive_skb+0xcc/0x290 net/core/dev.c:5639 process_backlog+0x364/0x780 net/core/dev.c:6516 __napi_poll+0xc0/0x430 net/core/dev.c:7075 napi_poll net/core/dev.c:7142 [inline] net_rx_action+0x4a8/0x9c0 net/core/dev.c:7232 handle_softirqs+0x328/0x820 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x12f/0x220 kernel/softirq.c:659 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671 instr_sysvec_call_function_single arch/x86/kernel/smp.c:243 [inline] sysvec_call_function_single+0x9d/0xc0 arch/x86/kernel/smp.c:243 asm_sysvec_call_function_single+0x16/0x20 arch/x86/include/asm/idtentry.h:684 The buggy address belongs to the object at ffff88805f382640 which belongs to the cache skbuff_head_cache of size 232 The buggy address is located 128 bytes inside of 232-byte region [ffff88805f382640, ffff88805f382728) The buggy address belongs to the page: page:ffffea00017ce080 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5f382 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 0000000000000000 dead000000000122 ffff88801b7e5140 raw: 0000000000000000 00000000000c000c 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 0x112a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_HARDWALL), pid 14, ts 223863395772, free_ts 223562140049 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x1b77/0x1c60 mm/page_alloc.c:4192 __alloc_pages+0x1e1/0x470 mm/page_alloc.c:5474 alloc_slab_page mm/slub.c:1775 [inline] allocate_slab mm/slub.c:1912 [inline] new_slab+0xc0/0x4b0 mm/slub.c:1975 ___slab_alloc+0x81e/0xdf0 mm/slub.c:3008 __slab_alloc mm/slub.c:3095 [inline] slab_alloc_node mm/slub.c:3186 [inline] kmem_cache_alloc_node+0x1c3/0x2d0 mm/slub.c:3256 __alloc_skb+0xf4/0x750 net/core/skbuff.c:415 alloc_skb include/linux/skbuff.h:1162 [inline] synproxy_send_client_synack+0x169/0xdd0 net/netfilter/nf_synproxy_core.c:482 nft_synproxy_eval_v4+0x36b/0x560 net/netfilter/nft_synproxy.c:59 nft_synproxy_do_eval+0x341/0x570 net/netfilter/nft_synproxy.c:141 expr_call_ops_eval net/netfilter/nf_tables_core.c:198 [inline] nft_do_chain+0x3fc/0x1420 net/netfilter/nf_tables_core.c:238 nft_do_chain_inet+0x22b/0x300 net/netfilter/nft_chain_filter.c:161 nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline] nf_hook_slow+0xb9/0x200 net/netfilter/core.c:584 nf_hook include/linux/netfilter.h:257 [inline] NF_HOOK+0x1cb/0x360 include/linux/netfilter.h:300 NF_HOOK+0x2d6/0x360 include/linux/netfilter.h:302 __netif_receive_skb_one_core net/core/dev.c:5525 [inline] __netif_receive_skb+0xcc/0x290 net/core/dev.c:5639 process_backlog+0x364/0x780 net/core/dev.c:6516 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1340 [inline] free_pcp_prepare mm/page_alloc.c:1391 [inline] free_unref_page_prepare+0x637/0x6c0 mm/page_alloc.c:3317 free_unref_page+0x94/0x280 mm/page_alloc.c:3396 kasan_depopulate_vmalloc_pte+0x67/0x80 mm/kasan/shadow.c:375 apply_to_pte_range mm/memory.c:2573 [inline] apply_to_pmd_range mm/memory.c:2617 [inline] apply_to_pud_range mm/memory.c:2653 [inline] apply_to_p4d_range mm/memory.c:2689 [inline] __apply_to_page_range+0x95c/0xc80 mm/memory.c:2725 kasan_release_vmalloc+0x93/0xb0 mm/kasan/shadow.c:485 __purge_vmap_area_lazy+0xc6e/0x18f0 mm/vmalloc.c:1704 _vm_unmap_aliases+0x410/0x4a0 mm/vmalloc.c:2107 change_page_attr_set_clr+0x311/0xc10 arch/x86/mm/pat/set_memory.c:1740 change_page_attr_clear arch/x86/mm/pat/set_memory.c:1797 [inline] set_memory_ro+0x89/0xd0 arch/x86/mm/pat/set_memory.c:1943 bpf_jit_binary_lock_ro include/linux/filter.h:899 [inline] bpf_int_jit_compile+0xc4a8/0xcc80 arch/x86/net/bpf_jit_comp.c:2478 bpf_prog_select_runtime+0x74f/0xaa0 kernel/bpf/core.c:1934 bpf_prog_load+0x106e/0x1550 kernel/bpf/syscall.c:2352 __sys_bpf+0x4c2/0x670 kernel/bpf/syscall.c:4651 __do_sys_bpf kernel/bpf/syscall.c:4755 [inline] __se_sys_bpf kernel/bpf/syscall.c:4753 [inline] __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:4753 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Memory state around the buggy address: ffff88805f382580: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc ffff88805f382600: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb >ffff88805f382680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805f382700: fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc ffff88805f382780: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 00 cc add %cl,%ah 2: 48 c7 c7 e0 92 59 8a mov $0xffffffff8a5992e0,%rdi 9: 48 c7 c6 20 93 59 8a mov $0xffffffff8a599320,%rsi 10: eb 00 jmp 0x12 12: 55 push %rbp 13: 41 57 push %r15 15: 41 56 push %r14 17: 53 push %rbx 18: 48 83 ec 10 sub $0x10,%rsp 1c: 65 48 8b 04 25 28 00 mov %gs:0x28,%rax 23: 00 00 25: 48 89 44 24 08 mov %rax,0x8(%rsp) * 2a: 65 8b 05 a9 d7 59 76 mov %gs:0x7659d7a9(%rip),%eax # 0x7659d7da <-- trapping instruction 31: 65 8b 0d 12 32 5a 76 mov %gs:0x765a3212(%rip),%ecx # 0x765a324a 38: f7 c1 ff ff ff 7f test $0x7fffffff,%ecx 3e: 74 1f je 0x5f