[v6.1] kernel BUG in ip6gre_header

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 2f3918bc53fb Linux 6.1.33
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=154cf455280000
kernel config: https://syzkaller.appspot.com/x/.config?x=64e29382e385f1b9
dashboard link: https://syzkaller.appspot.com/bug?extid=a7412cb792862ae2cf6e
compiler: Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2
userspace arch: arm64
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1645e4d9280000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16d64fb3280000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/f180a77b248f/disk-2f3918bc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/582d3206652e/vmlinux-2f3918bc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/20934119e0f6/Image-2f3918bc.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+a7412c...@syzkaller.appspotmail.com

skbuff: skb_under_panic: text:ffff8000110d7388 len:44 put:40 head:ffff0000cf3ab800 data:ffff0000cf3ab7ea tail:0x16 end:0xc0 dev:bond1
------------[ cut here ]------------
kernel BUG at net/core/skbuff.c:120!
Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 3892 Comm: dhcpcd Not tainted 6.1.33-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : skb_panic net/core/skbuff.c:116 [inline]
pc : skb_under_panic+0x13c/0x140 net/core/skbuff.c:130
lr : skb_panic net/core/skbuff.c:116 [inline]
lr : skb_under_panic+0x13c/0x140 net/core/skbuff.c:130
sp : ffff8000200672c0
x29: ffff8000200672d0 x28: 1fffe00018c349b1 x27: dfff800000000000
x26: ffff0000d2720290 x25: 0000000000000016 x24: ffff0000cf3ab7ea
x23: ffff0000cf3ab800 x22: 000000000000002c x21: 00000000000000c0
x20: 0000000000000028 x19: ffff8000110d7388 x18: ffff800020066820
x17: 0000000000000000 x16: ffff800012102bf4 x15: 0000000000000000
x14: 0000000000000000 x13: 0000000000000001 x12: 0000000000000001
x11: ff80800008345658 x10: 0000000000000000 x9 : e1f99bcd03577e00
x8 : e1f99bcd03577e00 x7 : 0000000000000001 x6 : 0000000000000001
x5 : ffff800020066bd8 x4 : ffff8000156a2a40 x3 : ffff8000085879f4
x2 : 0000000000000001 x1 : 0000000100000201 x0 : 0000000000000085
Call trace:
skb_panic net/core/skbuff.c:116 [inline]
skb_under_panic+0x13c/0x140 net/core/skbuff.c:130
skb_push+0x104/0x11c net/core/skbuff.c:2181
ip6gre_header+0xbc/0x67c net/ipv6/ip6_gre.c:1406
dev_hard_header include/linux/netdevice.h:3070 [inline]
lapbeth_data_transmit+0x1c4/0x298 drivers/net/wan/lapbether.c:257
lapb_data_transmit+0x8c/0xb0 net/lapb/lapb_iface.c:447
lapb_transmit_buffer+0x178/0x204 net/lapb/lapb_out.c:149
lapb_send_control+0x220/0x320 net/lapb/lapb_subr.c:251
lapb_establish_data_link+0x94/0xec
lapb_device_event+0x348/0x4e0
notifier_call_chain kernel/notifier.c:87 [inline]
raw_notifier_call_chain+0xd4/0x164 kernel/notifier.c:455
__dev_notify_flags+0x2ac/0x534
dev_change_flags+0xc8/0x154 net/core/dev.c:8624
devinet_ioctl+0x858/0x17e4 net/ipv4/devinet.c:1146
inet_ioctl+0x2ac/0x4d8 net/ipv4/af_inet.c:982
sock_do_ioctl+0x134/0x2dc net/socket.c:1174
sock_ioctl+0x4ec/0x858 net/socket.c:1291
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:870 [inline]
__se_sys_ioctl fs/ioctl.c:856 [inline]
__arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:856
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206
el0_svc+0x58/0x168 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:581
Code: aa1803e6 aa1903e7 a90023f5 947506cf (d4210000)
---[ end trace 0000000000000000 ]---


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