diff --git a/config.h b/config.h
index 45a1adf..7bff59c 100644
--- a/config.h
+++ b/config.h
@@ -85,3 +85,6 @@
 
 /* Location of the iptables lock file */
 #define XT_LOCK_NAME "/system/etc/xtables.lock"
+
+/* Define to 1 if you have the <linux/bpf.h> header file. */
+#define HAVE_LINUX_BPF_H 1
diff --git a/extensions/libxt_bpf.c b/extensions/libxt_bpf.c
index 92c445e..9510c19 100644
--- a/extensions/libxt_bpf.c
+++ b/extensions/libxt_bpf.c
@@ -22,6 +22,8 @@
 #include <linux/bpf.h>
 #endif
 
+#include <linux/unistd.h>
+
 #define BCODE_FILE_MAX_LEN_B	1024
 
 enum {