panic: mallocarray: overflow 18446744071562067968 * 8
Stopped at      db_enter+0x18:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
*512687  60499      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
wdc_isa_probe(ffffffff80000000,8,2) at wdc_isa_probe
wsmux_getmux(7fffffff) at wsmux_getmux+0x71 sys/dev/wscons/wsmux.c:152
wsmux_add_mux(7fffffff,ffff800000669100) at wsmux_add_mux+0x2f sys/dev/wscons/wsmux.c:594
VOP_IOCTL(fffffd802df5b2e0,80085761,ffff8000149dff70,42,fffffd803f7c68a0,ffff8000ffff2e28) at VOP_IOCTL+0x9a sys/kern/vfs_vops.c:290
vn_ioctl(fffffd80361b5cb0,80085761,ffff8000149dff70,ffff8000ffff2e28) at vn_ioctl+0xc9 sys/kern/vfs_vnops.c:512
sys_ioctl(ffff8000ffff2e28,ffff8000149e00b8,ffff8000149e00a0) at sys_ioctl+0x638
syscall(ffff8000149e0150) at syscall+0x541
Xsyscall(6,0,ffffffffffffff86,0,3,f0e2fbaf010) at Xsyscall+0x128
end of kernel
end trace frame: 0xf10bfb40b30, count: 5
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