diff --git a/configs/tplink_wdr4300_defconfig b/configs/tplink_wdr4300_defconfig
index 04b40b1..500e777 100644
--- a/configs/tplink_wdr4300_defconfig
+++ b/configs/tplink_wdr4300_defconfig
@@ -4,6 +4,7 @@
 CONFIG_SYS_MEMTEST_START=0x80100000
 CONFIG_SYS_MEMTEST_END=0x83f00000
 CONFIG_ENV_SIZE=0x10000
+CONFIG_SYS_MALLOC_LEN=0x40000
 CONFIG_DEFAULT_DEVICE_TREE="tplink_wdr4300"
 CONFIG_ARCH_ATH79=y
 CONFIG_BOARD_TPLINK_WDR4300=y