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/upnp/M-SEARCH.sh line 2:
UPNPMSG=`xmldbc -g /runtime/upnpmsg`
        ^--------------------------^ SC2006 (style): Use $(...) notation instead of legacy backticks `...`.

Did you mean:
UPNPMSG=$(xmldbc -g /runtime/upnpmsg)


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/upnp/M-SEARCH.sh line 4:
echo "[$0] GOT M-SEARCH: [$1 $2 $3 $4] ..." > $UPNPMSG
                                              ^------^ SC2086 (info): Double quote to prevent globbing and word splitting.

Did you mean:
echo "[$0] GOT M-SEARCH: [$1 $2 $3 $4] ..." > "$UPNPMSG"


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/upnp/M-SEARCH.sh line 6:
if [ -f /var/run/M-SEARCH.$2.$1.sh ]; then
                          ^-- SC2086 (info): Double quote to prevent globbing and word splitting.
                             ^-- SC2086 (info): Double quote to prevent globbing and word splitting.

Did you mean:
if [ -f /var/run/M-SEARCH."$2"."$1".sh ]; then


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/upnp/M-SEARCH.sh line 7:
	echo "[$0] The /var/run/M-SEARCH.$2.$1.sh is running, so do nothing & leave." > $UPNPMSG
                                                                                        ^------^ SC2086 (info): Double quote to prevent globbing and word splitting.

Did you mean:
	echo "[$0] The /var/run/M-SEARCH.$2.$1.sh is running, so do nothing & leave." > "$UPNPMSG"


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/upnp/M-SEARCH.sh line 9:
	xmldbc -P /etc/scripts/upnp/M-SEARCH.php -V "SEARCH_TARGET=$1" -V "TARGET_HOST=$2" -V "INF_UID=$3" -V "PARAM=$4" > /var/run/M-SEARCH.$2.$1.sh
                                                                                                                                             ^-- 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/scripts/upnp/M-SEARCH.php -V "SEARCH_TARGET=$1" -V "TARGET_HOST=$2" -V "INF_UID=$3" -V "PARAM=$4" > /var/run/M-SEARCH."$2"."$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/upnp/M-SEARCH.sh line 10:
	sh /var/run/M-SEARCH.$2.$1.sh
                             ^-- SC2086 (info): Double quote to prevent globbing and word splitting.
                                ^-- SC2086 (info): Double quote to prevent globbing and word splitting.

Did you mean:
	sh /var/run/M-SEARCH."$2"."$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/upnp/M-SEARCH.sh line 11:
	rm /var/run/M-SEARCH.$2.$1.sh
                             ^-- SC2086 (info): Double quote to prevent globbing and word splitting.
                                ^-- SC2086 (info): Double quote to prevent globbing and word splitting.

Did you mean:
	rm /var/run/M-SEARCH."$2"."$1".sh

For more information:
  https://www.shellcheck.net/wiki/SC2086 -- Double quote to prevent globbing ...
  https://www.shellcheck.net/wiki/SC2006 -- Use $(...) notation instead of le...

[*] Source file M-SEARCH.sh