================================================================== BUG: KASAN: use-after-free in skb_network_header include/linux/skbuff.h:2925 [inline] BUG: KASAN: use-after-free in ipv6_hdr include/linux/ipv6.h:101 [inline] BUG: KASAN: use-after-free in nf_nat_ipv6_in+0x11c/0x26c net/netfilter/nf_nat_proto.c:949 Read of size 8 at addr ffff0000f42e0c10 by task syz.3.984/7666 CPU: 0 PID: 7666 Comm: syz.3.984 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/31/2026 Call trace: dump_backtrace+0x1c4/0x1f0 arch/arm64/kernel/stacktrace.c:158 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165 __dump_stack+0x30/0x40 lib/dump_stack.c:88 dump_stack_lvl+0xf4/0x15c lib/dump_stack.c:106 print_address_description+0x88/0x218 mm/kasan/report.c:316 print_report+0x50/0x68 mm/kasan/report.c:420 kasan_report+0xa8/0xfc mm/kasan/report.c:524 __asan_report_load8_noabort+0x2c/0x38 mm/kasan/report_generic.c:351 skb_network_header include/linux/skbuff.h:2925 [inline] ipv6_hdr include/linux/ipv6.h:101 [inline] nf_nat_ipv6_in+0x11c/0x26c net/netfilter/nf_nat_proto.c:949 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow net/netfilter/core.c:614 [inline] nf_hook_slow_list+0x214/0x4e4 net/netfilter/core.c:653 NF_HOOK_LIST include/linux/netfilter.h:350 [inline] ip6_sublist_rcv+0xe08/0xf20 net/ipv6/ip6_input.c:318 ipv6_list_rcv+0x388/0x3e4 net/ipv6/ip6_input.c:355 __netif_receive_skb_list_ptype net/core/dev.c:5681 [inline] __netif_receive_skb_list_core+0x500/0x694 net/core/dev.c:5729 __netif_receive_skb_list net/core/dev.c:5781 [inline] netif_receive_skb_list_internal+0x6f0/0x99c net/core/dev.c:5872 netif_receive_skb_list+0x64/0x658 net/core/dev.c:5924 xdp_recv_frames net/bpf/test_run.c:256 [inline] xdp_test_run_batch net/bpf/test_run.c:334 [inline] bpf_test_run_xdp_live+0x13a8/0x1610 net/bpf/test_run.c:362 bpf_prog_test_run_xdp+0x618/0xd10 net/bpf/test_run.c:1457 bpf_prog_test_run+0x2dc/0x36c kernel/bpf/syscall.c:3748 __sys_bpf+0x504/0x660 kernel/bpf/syscall.c:5112 __do_sys_bpf kernel/bpf/syscall.c:5198 [inline] __se_sys_bpf kernel/bpf/syscall.c:5196 [inline] __arm64_sys_bpf+0x80/0x98 kernel/bpf/syscall.c:5196 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x12c arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:589 Allocated by task 7666: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4c/0x80 mm/kasan/common.c:53 kasan_save_alloc_info+0x24/0x30 mm/kasan/generic.c:505 __kasan_slab_alloc+0x70/0x88 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x74/0x430 mm/slab.h:742 kmem_cache_alloc_bulk+0x420/0x4e8 mm/slub.c:3887 xdp_recv_frames net/bpf/test_run.c:237 [inline] xdp_test_run_batch net/bpf/test_run.c:334 [inline] bpf_test_run_xdp_live+0x1258/0x1610 net/bpf/test_run.c:362 bpf_prog_test_run_xdp+0x618/0xd10 net/bpf/test_run.c:1457 bpf_prog_test_run+0x2dc/0x36c kernel/bpf/syscall.c:3748 __sys_bpf+0x504/0x660 kernel/bpf/syscall.c:5112 __do_sys_bpf kernel/bpf/syscall.c:5198 [inline] __se_sys_bpf kernel/bpf/syscall.c:5196 [inline] __arm64_sys_bpf+0x80/0x98 kernel/bpf/syscall.c:5196 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x12c arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:589 Freed by task 7666: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4c/0x80 mm/kasan/common.c:53 kasan_save_free_info+0x38/0x5c mm/kasan/generic.c:516 ____kasan_slab_free+0x148/0x1b0 mm/kasan/common.c:237 __kasan_slab_free+0x18/0x28 mm/kasan/common.c:245 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1735 [inline] slab_free_freelist_hook+0x16c/0x1e8 mm/slub.c:1761 slab_free mm/slub.c:3694 [inline] kmem_cache_free+0x118/0x318 mm/slub.c:3716 kfree_skbmem+0x10c/0x198 net/core/skbuff.c:-1 __kfree_skb net/core/skbuff.c:871 [inline] kfree_skb_reason+0x1a0/0x450 net/core/skbuff.c:893 NF_DROP_REASON include/linux/netfilter.h:29 [inline] nft_do_chain+0x12a0/0x1414 net/netfilter/nf_tables_core.c:-1 nft_nat_do_chain+0x20c/0x2ec net/netfilter/nft_chain_nat.c:32 nf_nat_inet_fn+0x5c4/0xa14 net/netfilter/nf_nat_core.c:752 nf_nat_ipv6_fn+0x1e4/0x290 net/netfilter/nf_nat_proto.c:937 nf_nat_ipv6_in+0xdc/0x26c net/netfilter/nf_nat_proto.c:947 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow net/netfilter/core.c:614 [inline] nf_hook_slow_list+0x214/0x4e4 net/netfilter/core.c:653 NF_HOOK_LIST include/linux/netfilter.h:350 [inline] ip6_sublist_rcv+0xe08/0xf20 net/ipv6/ip6_input.c:318 ipv6_list_rcv+0x388/0x3e4 net/ipv6/ip6_input.c:355 __netif_receive_skb_list_ptype net/core/dev.c:5681 [inline] __netif_receive_skb_list_core+0x500/0x694 net/core/dev.c:5729 __netif_receive_skb_list net/core/dev.c:5781 [inline] netif_receive_skb_list_internal+0x6f0/0x99c net/core/dev.c:5872 netif_receive_skb_list+0x64/0x658 net/core/dev.c:5924 xdp_recv_frames net/bpf/test_run.c:256 [inline] xdp_test_run_batch net/bpf/test_run.c:334 [inline] bpf_test_run_xdp_live+0x13a8/0x1610 net/bpf/test_run.c:362 bpf_prog_test_run_xdp+0x618/0xd10 net/bpf/test_run.c:1457 bpf_prog_test_run+0x2dc/0x36c kernel/bpf/syscall.c:3748 __sys_bpf+0x504/0x660 kernel/bpf/syscall.c:5112 __do_sys_bpf kernel/bpf/syscall.c:5198 [inline] __se_sys_bpf kernel/bpf/syscall.c:5196 [inline] __arm64_sys_bpf+0x80/0x98 kernel/bpf/syscall.c:5196 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x12c arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:589 The buggy address belongs to the object at ffff0000f42e0b40 which belongs to the cache skbuff_head_cache of size 240 The buggy address is located 208 bytes inside of 240-byte region [ffff0000f42e0b40, ffff0000f42e0c30) The buggy address belongs to the physical page: page:00000000561332f6 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1342e0 flags: 0x5ffc00000000200(slab|node=0|zone=2|lastcpupid=0x7ff) raw: 05ffc00000000200 fffffc0003277d80 dead000000000003 ffff0000c0bd4180 raw: 0000000000000000 00000000000c000c 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000f42e0b00: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb ffff0000f42e0b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff0000f42e0c00: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc ^ ffff0000f42e0c80: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000f42e0d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc ==================================================================