panic: tcp_output: template len != hdrlen - optlen
Stopped at      db_enter+0x18:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
*503951  63672      0        0x12          0    0  sshd
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398
panic(ffffffff823f6942) at panic+0x15c sys/kern/subr_prf.c:207
tcp_output(ffff800000ac2ee0) at tcp_output+0x2ad0 tcp_setpersist sys/netinet/tcp_output.c:1130 [inline]
tcp_output(ffff800000ac2ee0) at tcp_output+0x2ad0 sys/netinet/tcp_output.c:333
tcp_usrreq(fffffd805da70008,9,fffffd805c8e7d00,0,0,ffff80001d71cc40) at tcp_usrreq+0xa54
sosend(fffffd805da70008,0,ffff80001d6cd0e8,0,0,80) at sosend+0x669 sys/kern/uipc_socket.c:555
dofilewritev(ffff80001d71cc40,4,ffff80001d6cd0e8,0,ffff80001d6cd1d0) at dofilewritev+0x1ab sys/kern/sys_generic.c:365
sys_write(ffff80001d71cc40,ffff80001d6cd180,ffff80001d6cd1d0) at sys_write+0x83 sys/kern/sys_generic.c:285
syscall(ffff80001d6cd250) at syscall+0x507 sys/arch/amd64/amd64/trap.c:570
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7f7ffffbec10, count: 6
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