diff --git a/package/lean/autocore/files/arm/sbin/cpuinfo b/package/lean/autocore/files/arm/sbin/cpuinfo
index 0bf1818474..d64b95e6c9 100755
--- a/package/lean/autocore/files/arm/sbin/cpuinfo
+++ b/package/lean/autocore/files/arm/sbin/cpuinfo
@@ -12,7 +12,7 @@ elif grep -q "mvebu" "/etc/openwrt_release"; then
 	cpu_freq="$(cat "/proc/cpuinfo" | grep "BogoMIPS" | sed -n "1p" | awk -F ': ' '{print $2}')MHz"
 else
 	cpu_freq="$(expr $(cat /sys/devices/system/cpu/cpufreq/policy0/cpuinfo_cur_freq) / 1000)MHz"
-	big_cpu_freq="$(expr $(cat /sys/devices/system/cpu/cpufreq/policy4/cpuinfo_cur_freq) / 1000)"
+	big_cpu_freq="$(expr $(cat /sys/devices/system/cpu/cpufreq/policy4/cpuinfo_cur_freq 2>"/dev/null") / 1000 2>"/dev/null")"
 	[ -n "${big_cpu_freq}" ] && big_cpu_freq="${big_cpu_freq}MHz "
 fi