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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: 14097 Comm: syz-executor0 Not tainted 4.15.0-rc8+ #179
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: 0000:ffff8801d4ea77a0 EFLAGS: 00010282
RAX: 0000000000000086 RBX: ffff8801c7e07700 RCX: 0000000000000000
RDX: 0000000000000086 RSI: ffffc900016f4000 RDI: ffffed003a9d4ee8
RBP: ffff8801d4ea7808 R08: 1ffff1003a9d4e76 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff861f9a20
R13: ffffffff84a3818d R14: 0000000000000018 R15: ffff8801bf372740
FS:  0000000000000000(0000) GS:ffff8801db300000(0063) knlGS:00000000f7734b40
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 00007faa5effbec8 CR3: 00000001d52dd004 CR4: 00000000001606e0
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
 C_SYSC_sendmsg net/compat.c:739 [inline]
 compat_SyS_sendmsg+0x2a/0x40 net/compat.c:737
 do_syscall_32_irqs_on arch/x86/entry/common.c:327 [inline]
 do_fast_syscall_32+0x3ee/0xf9d arch/x86/entry/common.c:389
 entry_SYSENTER_compat+0x54/0x63 arch/x86/entry/entry_64_compat.S:129
RIP: 0023:0xf7f38c79
RSP: 002b:00000000f773408c EFLAGS: 00000296 ORIG_RAX: 0000000000000172
RAX: ffffffffffffffda RBX: 0000000000000014 RCX: 0000000020a72000
RDX: 000000002000c000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 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 e6 6d 28 fd <0f> 0b 4c 89 4d b8 4c 89 45 c0 48 89 75 c8 48 89 55 d0 e8 a7 c2 
RIP: skb_panic+0x162/0x1f0 net/core/skbuff.c:100 RSP: ffff8801d4ea77a0
---[ end trace e40a994e8c07889a ]---
Kernel panic - not syncing: Fatal exception
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..