diff --git a/mm/util.c b/mm/util.c
index ace2aea..18396ea 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -58,6 +58,40 @@
 }
 EXPORT_SYMBOL(kmemdup);
 
+/**
+ * krealloc - reallocate memory. The contents will remain unchanged.
+ * @p: object to reallocate memory for.
+ * @new_size: how many bytes of memory are required.
+ * @flags: the type of memory to allocate.
+ *
+ * The contents of the object pointed to are preserved up to the
+ * lesser of the new and old sizes.  If @p is %NULL, krealloc()
+ * behaves exactly like kmalloc().  If @size is 0 and @p is not a
+ * %NULL pointer, the object pointed to is freed.
+ */
+void *krealloc(const void *p, size_t new_size, gfp_t flags)
+{
+	void *ret;
+	size_t ks;
+
+	if (unlikely(!new_size)) {
+		kfree(p);
+		return NULL;
+	}
+
+	ks = ksize(p);
+	if (ks >= new_size)
+		return (void *)p;
+
+	ret = kmalloc_track_caller(new_size, flags);
+	if (ret) {
+		memcpy(ret, p, min(new_size, ks));
+		kfree(p);
+	}
+	return ret;
+}
+EXPORT_SYMBOL(krealloc);
+
 /*
  * strndup_user - duplicate an existing string from user space
  *