diff --git a/packages/network/connman/profile.d/connman.conf b/packages/network/connman/profile.d/connman.conf
index ec281cd8e6..c5b4f255a3 100644
--- a/packages/network/connman/profile.d/connman.conf
+++ b/packages/network/connman/profile.d/connman.conf
@@ -26,7 +26,7 @@ wait_for_inet_addr () {
   if [ "$WAIT_NETWORK" = "true" ] ; then
     progress "Wait for network"
     [ -z "$WAIT_NETWORK_TIME" ] && WAIT_NETWORK_TIME=10
-    LOOP_COUNT=$[$WAIT_NETWORK_TIME * 5]
+    LOOP_COUNT=$((WAIT_NETWORK_TIME * 5))
     for i in $(seq 1 $LOOP_COUNT) ; do
       cnt=$(ifconfig | sed -e '/inet addr:/!d' -e '/127.0.0.1/d' |wc -l)
       [ $cnt -gt 0 ] && break
diff --git a/packages/tools/hdparm/init.d/32_hdd-sleep b/packages/tools/hdparm/init.d/32_hdd-sleep
index 431aee9847..2df66fc17b 100644
--- a/packages/tools/hdparm/init.d/32_hdd-sleep
+++ b/packages/tools/hdparm/init.d/32_hdd-sleep
@@ -31,7 +31,7 @@ fi
   if [ "$HDD_STANDBY" == "true" ] ; then
     progress "Setup HDD standby"
     [ -z "$HDD_STANDBY_TIME" ] && HDD_STANDBY_TIME=15
-    STANDBY_TIME=$[$HDD_STANDBY_TIME * 12]
+    STANDBY_TIME=$((HDD_STANDBY_TIME * 12))
     for disk in /dev/sd?; do
       hdparm -S $STANDBY_TIME $disk > /dev/null 2>&1
     done