diff --git a/include/mbedtls/ssl.h b/include/mbedtls/ssl.h
index e3f8c8f..e07da11 100644
--- a/include/mbedtls/ssl.h
+++ b/include/mbedtls/ssl.h
@@ -2573,8 +2573,8 @@
  *
  * \param session  The session structure to be saved.
  * \param buf      The buffer to write the serialized data to. It must be a
- *                 writeable buffer of at least \p olen bytes, or may be \c
- *                 NULL if \p olen is \c 0.
+ *                 writeable buffer of at least \p buf_len bytes, or may be \c
+ *                 NULL if \p buf_len is \c 0.
  * \param buf_len  The number of bytes available for writing in \p buf.
  * \param olen     The size in bytes of the data that has been or would have
  *                 been written. It must point to a valid \c size_t.