Fix typo in doc and copy missing warning
diff --git a/include/mbedtls/camellia.h b/include/mbedtls/camellia.h
index 1d3610f..7e4721a 100644
--- a/include/mbedtls/camellia.h
+++ b/include/mbedtls/camellia.h
@@ -231,6 +231,10 @@
* Note that for both stategies, sizes are measured in blocks and
* that a CAMELLIA block is 16 bytes.
*
+ * \warning Upon return, \p stream_block contains sensitive data. Its
+ * content must not be written to insecure storage and should be
+ * securely discarded as soon as it's no longer needed.
+ *
* \param ctx CAMELLIA context
* \param length The length of the data
* \param nc_off The offset in the current stream_block (for resuming