diff --git a/target/linux/bcm4908/base-files/lib/upgrade/platform.sh b/target/linux/bcm4908/base-files/lib/upgrade/platform.sh
index e7d4bfe4de78bdd05ba3ff1cbac0504ddacfec0a..1b94801fb0f747ac2fd2cd4d7c01d0af5f121108 100644
--- a/target/linux/bcm4908/base-files/lib/upgrade/platform.sh
+++ b/target/linux/bcm4908/base-files/lib/upgrade/platform.sh
@@ -1,6 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0 OR BSD-2-Clause
 
-RAMFS_COPY_BIN="bcm4908img expr egrep fdtget fw_printenv fw_setenv tr"
+RAMFS_COPY_BIN="bcm4908img expr grep fdtget fw_printenv fw_setenv tr"
 
 PART_NAME=firmware
 
@@ -112,19 +112,19 @@ platform_pkgtb_get_image() {
 
 	local image_name=$(platform_pkgtb_get_image_name "$1" "$cmd" "$3")
 
-	$cmd < $1 | fdtget -p - /images/$image_name | egrep -q "^data$" && {
+	$cmd < $1 | fdtget -p - /images/$image_name | grep -Eq "^data$" && {
 		$cmd < $1 | fdtget -t r - /images/$image_name data
 		return
 	}
 
-	$cmd < $1 | fdtget -p - /images/$image_name | egrep -q "^data-position$" && {
+	$cmd < $1 | fdtget -p - /images/$image_name | grep -Eq "^data-position$" && {
 		local data_position=$($cmd < $1 | fdtget - /images/$image_name data-position)
 		local data_size=$($cmd < $1 | fdtget - /images/$image_name data-size)
 		$cmd < $1 2>/dev/null | dd skip=$data_position count=$data_size iflag=skip_bytes,count_bytes
 		return
 	}
 
-	$cmd < $1 | fdtget -p - /images/$image_name | egrep -q "^data-offset" && {
+	$cmd < $1 | fdtget -p - /images/$image_name | grep -Eq "^data-offset" && {
 		local data_offset=$($cmd < $1 | fdtget - /images/$image_name data-offset)
 		local totalsize=$(get_hex_u32_be "$1" 4)
 		local data_position=$(((0x$totalsize + data_offset + 3) & ~3))
diff --git a/target/linux/ipq806x/base-files/lib/upgrade/linksys.sh b/target/linux/ipq806x/base-files/lib/upgrade/linksys.sh
index 29f476345118298801e6e6ff07df7ddf6d33b371..1feffc7aa2420b7ef4ba9d0a29a2cd1657984f7a 100644
--- a/target/linux/ipq806x/base-files/lib/upgrade/linksys.sh
+++ b/target/linux/ipq806x/base-files/lib/upgrade/linksys.sh
@@ -9,7 +9,7 @@ linksys_get_target_firmware() {
 	cur_boot_part=$(/usr/sbin/fw_printenv -n boot_part)
 	if [ -z "${cur_boot_part}" ] ; then
 		mtd_ubi0=$(cat /sys/devices/virtual/ubi/ubi0/mtd_num)
-		case $(egrep ^mtd${mtd_ubi0}: /proc/mtd | cut -d '"' -f 2) in
+		case $(grep -E ^mtd${mtd_ubi0}: /proc/mtd | cut -d '"' -f 2) in
 		kernel1|rootfs1)
 			cur_boot_part=1
 			;;
diff --git a/target/linux/kirkwood/base-files/lib/upgrade/linksys.sh b/target/linux/kirkwood/base-files/lib/upgrade/linksys.sh
index 1f2596ea880cceb54699f66d03d2c64e3ec8a4b0..7e20276fe5f6f307086f94ac2a1c322c32b6131e 100644
--- a/target/linux/kirkwood/base-files/lib/upgrade/linksys.sh
+++ b/target/linux/kirkwood/base-files/lib/upgrade/linksys.sh
@@ -9,7 +9,7 @@ linksys_get_target_firmware() {
 	cur_boot_part=$(/usr/sbin/fw_printenv -n boot_part)
 	if [ -z "${cur_boot_part}" ] ; then
 		mtd_ubi0=$(cat /sys/devices/virtual/ubi/ubi0/mtd_num)
-		case $(egrep ^mtd${mtd_ubi0}: /proc/mtd | cut -d '"' -f 2) in
+		case $(grep -E ^mtd${mtd_ubi0}: /proc/mtd | cut -d '"' -f 2) in
 		kernel|rootfs)
 			cur_boot_part=1
 			;;
diff --git a/target/linux/mvebu/cortexa9/base-files/lib/upgrade/linksys.sh b/target/linux/mvebu/cortexa9/base-files/lib/upgrade/linksys.sh
index aaa32eb4ea787bc1dfbc662d368948104b474b41..826bf8c9b50f0ecfce13c91d230d72786c34ffba 100644
--- a/target/linux/mvebu/cortexa9/base-files/lib/upgrade/linksys.sh
+++ b/target/linux/mvebu/cortexa9/base-files/lib/upgrade/linksys.sh
@@ -9,7 +9,7 @@ linksys_get_target_firmware() {
 	cur_boot_part=$(/usr/sbin/fw_printenv -n boot_part)
 	if [ -z "${cur_boot_part}" ] ; then
 		mtd_ubi0=$(cat /sys/devices/virtual/ubi/ubi0/mtd_num)
-		case $(egrep ^mtd${mtd_ubi0}: /proc/mtd | cut -d '"' -f 2) in
+		case $(grep -E ^mtd${mtd_ubi0}: /proc/mtd | cut -d '"' -f 2) in
 		kernel1|rootfs1)
 			cur_boot_part=1
 			;;