------------[ cut here ]------------
refcount_t: saturated; leaking memory.
WARNING: CPU: 1 PID: 3861 at lib/refcount.c:78 refcount_add_not_zero+0x198/0x200 lib/refcount.c:78
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 3861 Comm: syz-executor4 Not tainted 4.14.0-rc8-mm1+ #21
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:53
 panic+0x1e4/0x41c kernel/panic.c:183
 __warn+0x1dc/0x200 kernel/panic.c:547
 report_bug+0x211/0x2d0 lib/bug.c:184
 fixup_bug+0x40/0x90 arch/x86/kernel/traps.c:177
 do_trap_no_signal arch/x86/kernel/traps.c:211 [inline]
 do_trap+0x260/0x390 arch/x86/kernel/traps.c:260
 do_error_trap+0x120/0x390 arch/x86/kernel/traps.c:297
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:310
 invalid_op+0x18/0x20 arch/x86/entry/entry_64.S:926
RIP: 0010:refcount_add_not_zero+0x198/0x200 lib/refcount.c:78
RSP: 0018:ffff8801c6f660d0 EFLAGS: 00010282
RAX: dffffc0000000008 RBX: 0000000000002901 RCX: ffffffff81599c5e
RDX: 0000000000006260 RSI: ffffc90003f7d000 RDI: ffff8801c6f65dd8
RBP: ffff8801c6f66160 R08: 1ffff10038decb97 R09: 0000000000000000
R10: ffff8801cdc7ac7a R11: 0000000000000000 R12: ffff8801c70b8da4
R13: 1ffff10038decc1b R14: 00000000ffffffff R15: 00000000fffffb76
 refcount_add+0x1b/0x60 lib/refcount.c:102
 tcp_gso_segment+0x10d0/0x16b0 net/ipv4/tcp_offload.c:155
 tcp4_gso_segment+0xd4/0x310 net/ipv4/tcp_offload.c:51
 inet_gso_segment+0x60c/0x11c0 net/ipv4/af_inet.c:1272
 skb_mac_gso_segment+0x33f/0x660 net/core/dev.c:2749
 __skb_gso_segment+0x35f/0x7f0 net/core/dev.c:2821
 skb_gso_segment include/linux/netdevice.h:3993 [inline]
 validate_xmit_skb+0x4ba/0xb20 net/core/dev.c:3074
 __dev_queue_xmit+0xe49/0x2070 net/core/dev.c:3497
 dev_queue_xmit+0x17/0x20 net/core/dev.c:3538
 neigh_hh_output include/net/neighbour.h:472 [inline]
 neigh_output include/net/neighbour.h:480 [inline]
 ip_finish_output2+0xece/0x1460 net/ipv4/ip_output.c:229
 ip_finish_output+0x85e/0xd10 net/ipv4/ip_output.c:317
 NF_HOOK_COND include/linux/netfilter.h:239 [inline]
 ip_output+0x1cc/0x860 net/ipv4/ip_output.c:405
 dst_output include/net/dst.h:460 [inline]
 ip_local_out+0x95/0x160 net/ipv4/ip_output.c:124
 ip_queue_xmit+0x8c6/0x18e0 net/ipv4/ip_output.c:504
 tcp_transmit_skb+0x1b0d/0x38b0 net/ipv4/tcp_output.c:1176
 tcp_write_xmit+0x680/0x5190 net/ipv4/tcp_output.c:2384
 __tcp_push_pending_frames+0xa0/0x250 net/ipv4/tcp_output.c:2558
 tcp_push+0x538/0x770 net/ipv4/tcp.c:735
 tcp_sendmsg_locked+0x26a3/0x3b80 net/ipv4/tcp.c:1429
 tcp_sendmsg+0x2f/0x50 net/ipv4/tcp.c:1466
 inet_sendmsg+0x11f/0x5e0 net/ipv4/af_inet.c:763
 sock_sendmsg_nosec net/socket.c:632 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:642
 ___sys_sendmsg+0x322/0x8a0 net/socket.c:2048
 __sys_sendmmsg+0x1e6/0x5f0 net/socket.c:2138
 SYSC_sendmmsg net/socket.c:2169 [inline]
 SyS_sendmmsg+0x35/0x60 net/socket.c:2164
 entry_SYSCALL_64_fastpath+0x1f/0x96
RIP: 0033:0x452879
RSP: 002b:00007f2b74f8cbe8 EFLAGS: 00000212 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 0000000000758020 RCX: 0000000000452879
RDX: 0000000000000007 RSI: 0000000020c0de5c RDI: 0000000000000016
RBP: 0000000000000086 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000004000000 R11: 0000000000000212 R12: 00000000006f2408
R13: 00000000ffffffff R14: 00007f2b74f8d6d4 R15: 0000000000000000
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..