2 files changed, 12 insertions, 0 deletions
diff --git a/crypto/buffer/buf_str.c b/crypto/buffer/buf_str.c
index fdde3d7db4ba..ebc5ab4646ce 100644
--- a/crypto/buffer/buf_str.c
+++ b/crypto/buffer/buf_str.c
@@ -60,6 +60,15 @@
 #include "cryptlib.h"
 #include <openssl/buffer.h>
 
+size_t BUF_strnlen(const char *str, size_t maxlen)
+{
+    const char *p;
+
+    for (p = str; maxlen-- != 0 && *p != '\0'; ++p) ;
+
+    return p - str;
+}
+
 char *BUF_strdup(const char *str)
 {
     if (str == NULL)
@@ -74,6 +83,8 @@ char *BUF_strndup(const char *str, size_t siz)
     if (str == NULL)
         return (NULL);
 
+    siz = BUF_strnlen(str, siz);
+
     ret = OPENSSL_malloc(siz + 1);
     if (ret == NULL) {
         BUFerr(BUF_F_BUF_STRNDUP, ERR_R_MALLOC_FAILURE);
diff --git a/crypto/buffer/buffer.h b/crypto/buffer/buffer.h
index 632df93c657c..c343dd772f1e 100644
--- a/crypto/buffer/buffer.h
+++ b/crypto/buffer/buffer.h
@@ -84,6 +84,7 @@ BUF_MEM *BUF_MEM_new(void);
 void BUF_MEM_free(BUF_MEM *a);
 int BUF_MEM_grow(BUF_MEM *str, size_t len);
 int BUF_MEM_grow_clean(BUF_MEM *str, size_t len);
+size_t BUF_strnlen(const char *str, size_t maxlen);
 char *BUF_strdup(const char *str);
 char *BUF_strndup(const char *str, size_t siz);
 void *BUF_memdup(const void *data, size_t siz);