bash-busybox, 95 bytes

Result

AC

Duration

1299ms

Code [DL]

f()for((;--w>1;)){
s=$c$s
}
read h
read w
c=' '
f
c="*$s*
"
s=
x=${c// /*}
w=$h
f
echo "$x$s$x"

stdin

50
11

stdout

***********
*         *
*         *
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*         *
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*         *
*         *
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*         *
*         *
*         *
*         *
*         *
*         *
*         *
*         *
***********

stderr