diff --git a/lib/asn1_decoder.c b/lib/asn1_decoder.c
index 11b9b01fda6b..1a000bb050f9 100644
--- a/lib/asn1_decoder.c
+++ b/lib/asn1_decoder.c
@@ -140,7 +140,7 @@ static int asn1_find_indefinite_length(const unsigned char *data, size_t datalen
  * @decoder: The decoder definition (produced by asn1_compiler)
  * @context: The caller's context (to be passed to the action functions)
  * @data: The encoded data
- * @datasize: The size of the encoded data
+ * @datalen: The size of the encoded data
  *
  * Decode BER/DER/CER encoded ASN.1 data according to a bytecode pattern
  * produced by asn1_compiler.  Action functions are called on marked tags to