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kernel BUG at net/core/skbuff.c:104!
invalid opcode: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 13622 Comm: syz-executor7 Not tainted 4.15.0-rc9+ #276
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:skb_panic+0x162/0x1f0 net/core/skbuff.c:100
RSP: 0018:ffff8801c994f940 EFLAGS: 00010282
RAX: 0000000000000083 RBX: ffff8801c400b800 RCX: 0000000000000000
RDX: 0000000000000083 RSI: ffffc900018af000 RDI: ffffed0039329f1c
RBP: ffff8801c994f9a8 R08: 1ffff10039329eaa R09: 0000000000000000
R10: ffff8801c994f7e8 R11: 0000000000000000 R12: ffffffff861f9a20
R13: ffffffff84a3818d R14: 0000000000000018 R15: ffff8801d7d1acc0
FS:  00007f6791dd9700(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000047e5d0 CR3: 00000001d44bd005 CR4: 00000000001626e0
Call Trace:
 skb_under_panic net/core/skbuff.c:114 [inline]
 skb_push+0xce/0xf0 net/core/skbuff.c:1714
 ipgre_header+0x6d/0x4e0 net/ipv4/ip_gre.c:877
 dev_hard_header include/linux/netdevice.h:2721 [inline]
 pppoe_sendmsg+0x58e/0x8b0 drivers/net/ppp/pppoe.c:890
 sock_sendmsg_nosec net/socket.c:638 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:648
 ___sys_sendmsg+0x767/0x8b0 net/socket.c:2028
 __sys_sendmsg+0xe5/0x210 net/socket.c:2062
 SYSC_sendmsg net/socket.c:2073 [inline]
 SyS_sendmsg+0x2d/0x50 net/socket.c:2069
 entry_SYSCALL_64_fastpath+0x29/0xa0
RIP: 0033:0x452f19
RSP: 002b:00007f6791dd8c58 EFLAGS: 00000212 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 000000000071bea0 RCX: 0000000000452f19
RDX: 0000000000000000 RSI: 0000000020ee9fc8 RDI: 0000000000000013
RBP: 00000000000005e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006f7da0
R13: 00000000ffffffff R14: 00007f6791dd96d4 R15: 0000000000000000
Code: 04 01 84 c0 74 04 3c 03 7e 23 8b 8b 80 00 00 00 41 57 48 c7 c7 e0 92 1f 86 52 56 4c 89 ea 41 50 4c 89 e6 45 89 f0 e8 86 6e 28 fd <0f> 0b 4c 89 4d b8 4c 89 45 c0 48 89 75 c8 48 89 55 d0 e8 67 bc 
RIP: skb_panic+0x162/0x1f0 net/core/skbuff.c:100 RSP: ffff8801c994f940
---[ end trace 3c009c298adc75e7 ]---
Kernel panic - not syncing: Fatal exception
Dumping ftrace buffer:
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Kernel Offset: disabled
Rebooting in 86400 seconds..