diff --git a/target/linux/brcm47xx/base-files/lib/upgrade/platform.sh b/target/linux/brcm47xx/base-files/lib/upgrade/platform.sh
index 0fc0388f6d6..a346933f9ac 100644
--- a/target/linux/brcm47xx/base-files/lib/upgrade/platform.sh
+++ b/target/linux/brcm47xx/base-files/lib/upgrade/platform.sh
@@ -148,8 +148,8 @@ platform_do_upgrade() {
 	local trx="$1"
 
 	case "$file_type" in
-		"chk")		trx="/tmp/$1.trx"; platform_extract_trx_from_chk "$1" "$trx";;
-		"cybertan")	trx="/tmp/$1.trx"; platform_extract_trx_from_cybertan "$1" "$trx";;
+		"chk")		trx="/tmp/$(basename $1).trx"; platform_extract_trx_from_chk "$1" "$trx";;
+		"cybertan")	trx="/tmp/$(basename $1).trx"; platform_extract_trx_from_cybertan "$1" "$trx";;
 	esac
 
 	shift