skbuff: skb_under_panic: text:ffffffff87eacdd0 len:74 put:14 head:ffff888078a02c00 data:ffff888078a02bf2 tail:0x3c end:0xc0 dev:syz_tun ------------[ cut here ]------------ kernel BUG at net/core/skbuff.c:112! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 18330 Comm: syz.1.3929 Not tainted 5.15.185-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:skb_panic+0x150/0x160 net/core/skbuff.c:112 Code: c7 20 ab fd 8a 48 8b 74 24 08 48 8b 54 24 10 8b 0c 24 44 8b 44 24 04 4d 89 e9 41 52 55 41 57 41 56 e8 04 33 f6 ff 48 83 c4 20 <0f> 0b 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 00 55 48 89 e5 41 57 RSP: 0018:ffffc9000335ecc0 EFLAGS: 00010286 RAX: 0000000000000087 RBX: dffffc0000000000 RCX: d235c9f2fe5fc300 RDX: ffffc90004034000 RSI: 00000000000040eb RDI: 00000000000040ec RBP: 00000000000000c0 R08: dffffc0000000000 R09: ffffed10172267a8 R10: ffffed10172267a8 R11: 1ffff110172267a7 R12: ffff8880799e0510 R13: ffff888078a02c00 R14: ffff888078a02bf2 R15: 000000000000003c FS: 00007fe5872ce6c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c26431d CR3: 000000006245f000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: skb_under_panic net/core/skbuff.c:122 [inline] skb_push+0xba/0xd0 net/core/skbuff.c:2053 eth_header+0x30/0x200 net/ethernet/eth.c:82 dev_hard_header include/linux/netdevice.h:3296 [inline] nf_send_reset6+0xb65/0xfa0 net/ipv6/netfilter/nf_reject_ipv6.c:354 nft_reject_inet_eval+0x325/0x680 net/netfilter/nft_reject_inet.c:48 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 include/linux/netfilter.h:300 [inline] br_nf_pre_routing_ipv6+0x52b/0x650 net/bridge/br_netfilter_ipv6.c:237 nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline] nf_hook_bridge_pre net/bridge/br_input.c:242 [inline] br_handle_frame+0x89b/0x1180 net/bridge/br_input.c:384 __netif_receive_skb_core+0xfb0/0x35d0 net/core/dev.c:5419 __netif_receive_skb_one_core net/core/dev.c:5523 [inline] __netif_receive_skb+0x74/0x290 net/core/dev.c:5639 netif_receive_skb_internal net/core/dev.c:5725 [inline] netif_receive_skb+0x19e/0x6c0 net/core/dev.c:5784 tun_rx_batched+0x5a1/0x6d0 drivers/net/tun.c:-1 tun_get_user+0x23f0/0x38d0 drivers/net/tun.c:1989 tun_chr_write_iter+0x112/0x1e0 drivers/net/tun.c:2019 call_write_iter include/linux/fs.h:2172 [inline] new_sync_write fs/read_write.c:507 [inline] vfs_write+0x712/0xd00 fs/read_write.c:594 ksys_write+0x14d/0x250 fs/read_write.c:647 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 RIP: 0033:0x7fe5894653df Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 f9 92 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 4c 93 02 00 48 RSP: 002b:00007fe5872ce000 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fe58968dfa0 RCX: 00007fe5894653df RDX: 000000000000004e RSI: 00002000000001c0 RDI: 00000000000000c8 RBP: 00007fe5894e8ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000000004e R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fe58968dfa0 R15: 00007ffd971e6538 Modules linked in: ---[ end trace 3bcd82338f5769fe ]--- RIP: 0010:skb_panic+0x150/0x160 net/core/skbuff.c:112 Code: c7 20 ab fd 8a 48 8b 74 24 08 48 8b 54 24 10 8b 0c 24 44 8b 44 24 04 4d 89 e9 41 52 55 41 57 41 56 e8 04 33 f6 ff 48 83 c4 20 <0f> 0b 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 00 55 48 89 e5 41 57 RSP: 0018:ffffc9000335ecc0 EFLAGS: 00010286 RAX: 0000000000000087 RBX: dffffc0000000000 RCX: d235c9f2fe5fc300 RDX: ffffc90004034000 RSI: 00000000000040eb RDI: 00000000000040ec RBP: 00000000000000c0 R08: dffffc0000000000 R09: ffffed10172267a8 R10: ffffed10172267a8 R11: 1ffff110172267a7 R12: ffff8880799e0510 R13: ffff888078a02c00 R14: ffff888078a02bf2 R15: 000000000000003c FS: 00007fe5872ce6c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c26431d CR3: 000000006245f000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400