diff --git a/fs/ubifs/ubifs.c b/fs/ubifs/ubifs.c
index f9b4f4b..97cbe49 100644
--- a/fs/ubifs/ubifs.c
+++ b/fs/ubifs/ubifs.c
@@ -86,23 +86,6 @@
 #ifdef __BAREBOX__
 /* from mm/util.c */
 
-/**
- * kmemdup - duplicate region of memory
- *
- * @src: memory region to duplicate
- * @len: memory region length
- * @gfp: GFP mask to use
- */
-void *kmemdup(const void *src, size_t len, gfp_t gfp)
-{
-	void *p;
-
-	p = kmalloc(len, gfp);
-	if (p)
-		memcpy(p, src, len);
-	return p;
-}
-
 struct crypto_comp {
 	int compressor;
 };
diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h
index 19af05a..d4df668 100644
--- a/fs/ubifs/ubifs.h
+++ b/fs/ubifs/ubifs.h
@@ -71,8 +71,6 @@
 	struct inode *inode;
 };
 
-void *kmemdup(const void *src, size_t len, gfp_t gfp);
-
 /* uapi/linux/limits.h */
 #define XATTR_LIST_MAX 65536	/* size of extended attribute namelist (64k) */
 
diff --git a/include/linux/string.h b/include/linux/string.h
index ed4eeb5..3418b4f 100644
--- a/include/linux/string.h
+++ b/include/linux/string.h
@@ -115,4 +115,11 @@
 }
 #endif
 
+void *memdup(const void *, size_t);
+
+static inline void *kmemdup(const void *src, size_t len, gfp_t gfp)
+{
+	return memdup(src, len);
+}
+
 #endif /* _LINUX_STRING_H_ */
diff --git a/include/string.h b/include/string.h
index 6ceb332..8c63f22 100644
--- a/include/string.h
+++ b/include/string.h
@@ -3,7 +3,6 @@
 
 #include <linux/string.h>
 
-void *memdup(const void *, size_t);
 int strtobool(const char *str, int *val);
 
 void *__default_memset(void *, int, __kernel_size_t);