kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
l2tp_ppp: sess 59/4096: set debug=f55d40e
l2tp_ppp: sess 59/4096: set flags=0
   (ftrace buffer empty)
Modules linked in:
CPU: 0 PID: 1228 Comm: syz-executor1 Not tainted 4.15.0-rc8+ #198
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:ccid_hc_tx_send_packet net/dccp/ccid.h:169 [inline]
RIP: 0010:dccp_write_xmit+0x69/0x1d0 net/dccp/output.c:353
RSP: 0018:ffff8801d091f748 EFLAGS: 00010246
RAX: 0000000000010000 RBX: ffff8801c749ed80 RCX: ffffffff8508f891
RDX: 0000000000000000 RSI: ffffc900025fd000 RDI: ffff8801c749ed80
RBP: ffff8801d091f778 R08: 1ffff1003a123eab R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801ccd2b700
R13: dffffc0000000000 R14: ffffed0038e93eab R15: 0000000000000000
FS:  00007fabac137700(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000920008 CR3: 00000001d301a004 CR4: 00000000001606f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 dccp_sendmsg+0x95f/0xdc0 net/dccp/proto.c:813
 inet_sendmsg+0x11f/0x5e0 net/ipv4/af_inet.c:764
 sock_sendmsg_nosec net/socket.c:630 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:640
 ___sys_sendmsg+0x320/0x8b0 net/socket.c:2020
 __sys_sendmmsg+0x1ee/0x620 net/socket.c:2110
 SYSC_sendmmsg net/socket.c:2141 [inline]
 SyS_sendmmsg+0x35/0x60 net/socket.c:2136
 entry_SYSCALL_64_fastpath+0x29/0xa0
RIP: 0033:0x452ee9
RSP: 002b:00007fabac136c58 EFLAGS: 00000212 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 000000000071bea0 RCX: 0000000000452ee9
RDX: 04444444444441b5 RSI: 0000000020234f10 RDI: 0000000000000014
RBP: 00000000000003bf R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006f4a88
R13: 00000000ffffffff R14: 00007fabac1376d4 R15: 0000000000000000
Code: 00 00 48 85 c0 49 89 c4 0f 84 fb 00 00 00 e8 df 26 67 fc 41 80 3e 00 0f 85 5a 01 00 00 4c 8b bb d8 07 00 00 4c 89 fa 48 c1 ea 03 <42> 80 3c 2a 00 0f 85 34 01 00 00 4d 8b 3f 49 8d bf b0 00 00 00 
RIP: ccid_hc_tx_send_packet net/dccp/ccid.h:169 [inline] RSP: ffff8801d091f748
RIP: dccp_write_xmit+0x69/0x1d0 net/dccp/output.c:353 RSP: ffff8801d091f748
---[ end trace bb0322ebea7b515c ]---
Kernel panic - not syncing: Fatal exception
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..