panic: mallocarray: overflow 18446744071562067968 * 8
Stopped at      db_enter+0x18:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
*360388  22774      0           0  0x4000000    0  syz-executor.1
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:399
panic() at panic+0x15c sys/kern/subr_prf.c:208
ipgphy_probe(ffffffff80000000,8,2) at ipgphy_probe
wsmux_getmux(7fffffff) at wsmux_getmux+0x71 sys/dev/wscons/wsmux.c:152
wsmux_add_mux(7fffffff,ffff800001972100) at wsmux_add_mux+0x2f sys/dev/wscons/wsmux.c:594
VOP_IOCTL(fffffd803c9bc660,80085761,ffff800014a1fe30,f,fffffd803f7c6780,ffff8000149ef080) at VOP_IOCTL+0x9a sys/kern/vfs_vops.c:290
vn_ioctl(fffffd803c4ed708,80085761,ffff800014a1fe30,ffff8000149ef080) at vn_ioctl+0xc9 sys/kern/vfs_vnops.c:512
sys_ioctl(ffff8000149ef080,ffff800014a1ff78,ffff800014a1ff60) at sys_ioctl+0x638
syscall(ffff800014a20010) at syscall+0x541
Xsyscall(6,0,ffffffffffffff86,0,3,372811f8010) at Xsyscall+0x128
end of kernel
end trace frame: 0x37516940720, count: 5
https://www.openbsd.org/ddb.html describes the minimum info required in bug
reports.  Insufficient info makes it difficult to find and fix bugs.