In /logs/firmware/unblob_extracted/firmware_extract/DIR-600_fw_revb5_214b01_ALL_de_20130122/dir600b_v2.14_d1mg.bin_extract/1179788-3612812.squashfs_v4_le_extract/etc/scripts/ip-down line 2:
echo [$0]: ifname[$1] device[$2] speed[$3] ip[$4] remote[$5] param[$6] > /dev/console
      ^-- SC2086 (info): Double quote to prevent globbing and word splitting.
                  ^-- SC2086 (info): Double quote to prevent globbing and word splitting.
                             ^-- SC2086 (info): Double quote to prevent globbing and word splitting.
                                       ^-- SC2086 (info): Double quote to prevent globbing and word splitting.
                                              ^-- SC2086 (info): Double quote to prevent globbing and word splitting.
                                                         ^-- SC2086 (info): Double quote to prevent globbing and word splitting.
                                                                   ^-- SC2086 (info): Double quote to prevent globbing and word splitting.

Did you mean:
echo ["$0"]: ifname["$1"] device["$2"] speed["$3"] ip["$4"] remote["$5"] param["$6"] > /dev/console


In /logs/firmware/unblob_extracted/firmware_extract/DIR-600_fw_revb5_214b01_ALL_de_20130122/dir600b_v2.14_d1mg.bin_extract/1179788-3612812.squashfs_v4_le_extract/etc/scripts/ip-down line 3:
xmldbc -P /etc/services/INET/ppp4_ipdown.php -V IFNAME=$1 -V DEVICE=$2 -V SPEED=$3 -V IP=$4 -V REMOTE=$5 -V PARAM=$6 > /var/run/ppp4_ipdown_$1.sh
                                                       ^-- SC2086 (info): Double quote to prevent globbing and word splitting.
                                                                    ^-- SC2086 (info): Double quote to prevent globbing and word splitting.
                                                                                ^-- SC2086 (info): Double quote to prevent globbing and word splitting.
                                                                                         ^-- SC2086 (info): Double quote to prevent globbing and word splitting.
                                                                                                      ^-- SC2086 (info): Double quote to prevent globbing and word splitting.
                                                                                                                  ^-- SC2086 (info): Double quote to prevent globbing and word splitting.
                                                                                                                                            ^-- SC2086 (info): Double quote to prevent globbing and word splitting.

Did you mean:
xmldbc -P /etc/services/INET/ppp4_ipdown.php -V IFNAME="$1" -V DEVICE="$2" -V SPEED="$3" -V IP="$4" -V REMOTE="$5" -V PARAM="$6" > /var/run/ppp4_ipdown_"$1".sh


In /logs/firmware/unblob_extracted/firmware_extract/DIR-600_fw_revb5_214b01_ALL_de_20130122/dir600b_v2.14_d1mg.bin_extract/1179788-3612812.squashfs_v4_le_extract/etc/scripts/ip-down line 4:
sh /var/run/ppp4_ipdown_$1.sh
                        ^-- SC2086 (info): Double quote to prevent globbing and word splitting.

Did you mean:
sh /var/run/ppp4_ipdown_"$1".sh

For more information:
  https://www.shellcheck.net/wiki/SC2086 -- Double quote to prevent globbing ...

[*] Source file ip-down