diff --git a/ChangeLog b/ChangeLog
index 588b833..82c50a0 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,11 @@
 mbed TLS ChangeLog (Sorted per branch, date)
 
+= mbed TLS 2.1.x released xxxx-xx-xx
+
+Bugfix
+   * Clarify documentation for mbedtls_ssl_write() to include 0 as a valid
+     return value. Found by @davidwu2000. #839
+
 = mbed TLS 2.1.13 branch released 2018-06-18
 
 Bugfix