skbuff: skb_under_panic: text:ffffffff845f50a0 len:920 put:20 head:ffff888171931000 data:ffff888171930ff8 tail:0x390 end:0x680 dev:gre4 ------------[ cut here ]------------ kernel BUG at net/core/skbuff.c:120! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 0 PID: 12705 Comm: kworker/0:0 Not tainted 6.1.43-syzkaller-00022-g8f46c3493178 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023 Workqueue: mld mld_ifc_work RIP: 0010:skb_panic net/core/skbuff.c:120 [inline] RIP: 0010:skb_under_panic+0x14c/0x150 net/core/skbuff.c:130 Code: 60 98 da 85 48 c7 c6 05 6b 2f 86 48 8b 55 c0 8b 4d d4 44 8b 45 d0 4c 8b 4d c8 53 41 55 41 54 41 57 e8 fc db f4 00 48 83 c4 20 <0f> 0b 66 90 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 ec 18 41 RSP: 0018:ffffc9000551f0a0 EFLAGS: 00010286 RAX: 0000000000000087 RBX: ffff888162226000 RCX: 98ecdd4da3f28000 RDX: 0000000000000000 RSI: 0000000000000400 RDI: 0000000000000000 RBP: ffffc9000551f0e0 R08: ffffffff815a9ea5 R09: fffff52000aa3dad R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000390 R13: 0000000000000680 R14: dffffc0000000000 R15: ffff888171930ff8 FS: 0000000000000000(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2f421000 CR3: 000000010f5a3000 CR4: 00000000003506b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: skb_push+0xf3/0x120 net/core/skbuff.c:2181 iptunnel_xmit+0x2d0/0x940 net/ipv4/ip_tunnel_core.c:67 ip_tunnel_xmit+0x218f/0x2ae0 net/ipv4/ip_tunnel.c:813 __gre_xmit net/ipv4/ip_gre.c:469 [inline] ipgre_xmit+0x7ac/0xaa0 net/ipv4/ip_gre.c:661 __netdev_start_xmit include/linux/netdevice.h:4908 [inline] netdev_start_xmit include/linux/netdevice.h:4922 [inline] xmit_one net/core/dev.c:3602 [inline] dev_hard_start_xmit+0x1de/0x630 net/core/dev.c:3618 __dev_queue_xmit+0x18c0/0x3700 net/core/dev.c:4268 dev_queue_xmit include/linux/netdevice.h:3076 [inline] neigh_direct_output+0x17/0x20 net/core/neighbour.c:1592 neigh_output include/net/neighbour.h:552 [inline] ip6_finish_output2+0x104a/0x1820 net/ipv6/ip6_output.c:134 __ip6_finish_output net/ipv6/ip6_output.c:195 [inline] ip6_finish_output+0x5d9/0xb60 net/ipv6/ip6_output.c:206 NF_HOOK_COND include/linux/netfilter.h:294 [inline] ip6_output+0x1f7/0x4d0 net/ipv6/ip6_output.c:227 dst_output include/net/dst.h:444 [inline] NF_HOOK include/linux/netfilter.h:305 [inline] mld_sendpack+0x803/0xe40 net/ipv6/mcast.c:1820 mld_send_cr net/ipv6/mcast.c:2121 [inline] mld_ifc_work+0x7dc/0xba0 net/ipv6/mcast.c:2653 process_one_work+0x73d/0xcb0 kernel/workqueue.c:2299 worker_thread+0xa60/0x1260 kernel/workqueue.c:2446 kthread+0x26d/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:skb_panic net/core/skbuff.c:120 [inline] RIP: 0010:skb_under_panic+0x14c/0x150 net/core/skbuff.c:130 Code: 60 98 da 85 48 c7 c6 05 6b 2f 86 48 8b 55 c0 8b 4d d4 44 8b 45 d0 4c 8b 4d c8 53 41 55 41 54 41 57 e8 fc db f4 00 48 83 c4 20 <0f> 0b 66 90 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 ec 18 41 RSP: 0018:ffffc9000551f0a0 EFLAGS: 00010286 RAX: 0000000000000087 RBX: ffff888162226000 RCX: 98ecdd4da3f28000 RDX: 0000000000000000 RSI: 0000000000000400 RDI: 0000000000000000 RBP: ffffc9000551f0e0 R08: ffffffff815a9ea5 R09: fffff52000aa3dad R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000390 R13: 0000000000000680 R14: dffffc0000000000 R15: ffff888171930ff8 FS: 0000000000000000(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2f421000 CR3: 000000010f5a3000 CR4: 00000000003506b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400