diff --git a/build_library/extract-initramfs-from-vmlinuz.sh b/build_library/extract-initramfs-from-vmlinuz.sh
index 50fbc9fea0..d46d9137de 100755
--- a/build_library/extract-initramfs-from-vmlinuz.sh
+++ b/build_library/extract-initramfs-from-vmlinuz.sh
@@ -29,8 +29,12 @@ try_extract() {
     # cpio can do strange things when given garbage, so do a basic check.
     [[ $(head -c6 "$1") == 070701 ]] || return 0
 
-    # There may be multiple concatenated archives so try cpio till it fails.
-    while cpio --quiet --extract --make-directories --directory="${out}/rootfs-${ROOTFS_IDX}" --nonmatching 'dev/*' 2>/dev/null; do
+    while {
+        # cpio needs the directory to exist first. Fail if it's already there.
+        { mkdir "${out}/rootfs-${ROOTFS_IDX}" || return $?; } &&
+        # There may be multiple concatenated archives so try cpio till it fails.
+        cpio --quiet --extract --make-directories --directory="${out}/rootfs-${ROOTFS_IDX}" --nonmatching 'dev/*' 2>/dev/null
+    }; do
         ROOTFS_IDX=$(( ROOTFS_IDX + 1 ))
     done < "$1"