diff --git a/kern/libkern/stdlib.c b/kern/libkern/stdlib.c
new file mode 100644
index 0000000..531df0e
--- /dev/null
+++ b/kern/libkern/stdlib.c
@@ -0,0 +1,13 @@
+#include <stdlib.h>
+
+int abs(int a) {
+    return a > 0 ? a : -a;
+}
+
+long labs(long a) {
+    return a > 0 ? a : -a;
+}
+
+long long llabs(long long a) {
+    return a > 0 ? a : -a;
+}
diff --git a/kern/libkern/stdlib.h b/kern/libkern/stdlib.h
index fde3746..0afdf3a 100644
--- a/kern/libkern/stdlib.h
+++ b/kern/libkern/stdlib.h
@@ -4,4 +4,8 @@
 #define EXIT_SUCCESS 0
 #define EXIT_FAILURE 1
 
+int       abs(int);
+long      labs(long);
+long long llabs(long long);
+
 #endif // STDLIB_H