diff --git a/tools/testing/selftests/net/forwarding/lib.sh b/tools/testing/selftests/net/forwarding/lib.sh
index 1c4f866de7d7..3d8e4ebda1b6 100755
--- a/tools/testing/selftests/net/forwarding/lib.sh
+++ b/tools/testing/selftests/net/forwarding/lib.sh
@@ -914,14 +914,14 @@ sysctl_set()
 	local value=$1; shift
 
 	SYSCTL_ORIG[$key]=$(sysctl -n $key)
-	sysctl -qw $key=$value
+	sysctl -qw $key="$value"
 }
 
 sysctl_restore()
 {
 	local key=$1; shift
 
-	sysctl -qw $key=${SYSCTL_ORIG["$key"]}
+	sysctl -qw $key="${SYSCTL_ORIG[$key]}"
 }
 
 forwarding_enable()