------------[ cut here ]------------
kernel BUG at net/l2tp/l2tp_ppp.c:176!
invalid opcode: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 2159 Comm: syz-executor1 Not tainted 4.15.0-rc8+ #196
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:pppol2tp_sock_to_session net/l2tp/l2tp_ppp.c:176 [inline]
RIP: 0010:pppol2tp_sendmsg+0x512/0x670 net/l2tp/l2tp_ppp.c:304
RSP: 0018:ffff8801c5017438 EFLAGS: 00010216
RAX: 0000000000010000 RBX: ffff8801d87c8ec0 RCX: ffffffff850625f2
RDX: 000000000000021f RSI: ffffc900021fe000 RDI: ffff8801d87c92a0
RBP: ffff8801c50174a8 R08: 0000000000000000 R09: 1ffff10038a02e17
R10: 0000000000000003 R11: 0000000000000001 R12: ffff8801cfe84040
R13: 0000000000000000 R14: 0000000000000010 R15: 0000000000000000
FS:  00007f5434dcb700(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000201fcfc8 CR3: 00000001bf74a004 CR4: 00000000001606e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 sock_sendmsg_nosec net/socket.c:630 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:640
 kernel_sendmsg+0x47/0x60 net/socket.c:648
 sock_no_sendpage+0x1cc/0x280 net/core/sock.c:2581
 kernel_sendpage+0xbf/0xe0 net/socket.c:3360
 kcm_write_msgs+0x404/0x1b80 net/kcm/kcmsock.c:646
 kcm_sendmsg+0x148d/0x22d0 net/kcm/kcmsock.c:1035
 sock_sendmsg_nosec net/socket.c:630 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:640
 ___sys_sendmsg+0x767/0x8b0 net/socket.c:2020
 __sys_sendmsg+0xe5/0x210 net/socket.c:2054
 SYSC_sendmsg net/socket.c:2065 [inline]
 SyS_sendmsg+0x2d/0x50 net/socket.c:2061
 entry_SYSCALL_64_fastpath+0x29/0xa0
RIP: 0033:0x452e99
RSP: 002b:00007f5434dcac58 EFLAGS: 00000212 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 000000000071bea0 RCX: 0000000000452e99
RDX: 0000000000000000 RSI: 00000000201fcfc8 RDI: 0000000000000017
RBP: 0000000000000373 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006f3368
R13: 00000000ffffffff R14: 00007f5434dcb6d4 R15: 0000000000000000
Code: a5 f9 69 fc 48 8b 7d d0 e8 9c 74 55 fd 84 c0 74 0d e8 93 f9 69 fc 48 89 df e8 1b 80 2b ff 41 bd f7 ff ff ff eb 86 e8 7e f9 69 fc <0f> 0b 41 bd 95 ff ff ff e9 74 ff ff ff e8 4c e7 a1 fc e9 77 fb 
RIP: pppol2tp_sock_to_session net/l2tp/l2tp_ppp.c:176 [inline] RSP: ffff8801c5017438
RIP: pppol2tp_sendmsg+0x512/0x670 net/l2tp/l2tp_ppp.c:304 RSP: ffff8801c5017438
---[ end trace 32ebde7702f5ff85 ]---
------------[ cut here ]------------
kernel BUG at net/l2tp/l2tp_ppp.c:176!
invalid opcode: 0000 [#2] SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 2179 Comm: syz-executor1 Tainted: G      D          4.15.0-rc8+ #196
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:pppol2tp_sock_to_session net/l2tp/l2tp_ppp.c:176 [inline]
RIP: 0010:pppol2tp_ioctl+0x582/0x730 net/l2tp/l2tp_ppp.c:1229
RSP: 0018:ffff8801c3cefbd8 EFLAGS: 00010212
RAX: 0000000000010000 RBX: ffff8801d87c8ec0 RCX: ffffffff85063232
RDX: 0000000000000055 RSI: ffffc90002a0e000 RDI: ffff8801d87c8f40
RBP: ffff8801c3cefcc8 R08: 0000000000000000 R09: 0000000000000000
R10: ffff8801c3cefb78 R11: ffff8801d87c8fd0 R12: 1ffff1003879df80
R13: ffff8801cfe84040 R14: ffff8801c3cefca0 R15: ffffffff85062cb0
FS:  00007f5434daa700(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000715a2c CR3: 00000001bf74a001 CR4: 00000000001606e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 pppox_ioctl+0x1c7/0x250 drivers/net/ppp/pppox.c:97
 sock_do_ioctl+0x65/0xb0 net/socket.c:958
 sock_ioctl+0x2c2/0x440 net/socket.c:1055
 vfs_ioctl fs/ioctl.c:46 [inline]
 do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:686
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
 entry_SYSCALL_64_fastpath+0x29/0xa0
RIP: 0033:0x452e99
RSP: 002b:00007f5434da9c58 EFLAGS: 00000212 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 000000000071bf58 RCX: 0000000000452e99
RDX: 00000000206abff8 RSI: 00000000000089e0 RDI: 0000000000000013
RBP: 00000000000003bb R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006f3a28
R13: 00000000ffffffff R14: 00007f5434daa6d4 R15: 0000000000000016
Code: 00 89 85 30 ff ff ff e8 5d 68 55 fd 84 c0 0f 84 a1 fe ff ff e8 50 ed 69 fc 4c 89 f7 e8 78 1c ff ff e9 8f fe ff ff e8 3e ed 69 fc <0f> 0b e8 37 ed 69 fc 48 8b bd 20 ff ff ff e8 2b 68 55 fd 84 c0 
RIP: pppol2tp_sock_to_session net/l2tp/l2tp_ppp.c:176 [inline] RSP: ffff8801c3cefbd8
RIP: pppol2tp_ioctl+0x582/0x730 net/l2tp/l2tp_ppp.c:1229 RSP: ffff8801c3cefbd8
---[ end trace 32ebde7702f5ff86 ]---