diff --git a/common/tlv-parser.c b/common/tlv-parser.c
index bc22c4f4f..2cafac3e9 100644
--- a/common/tlv-parser.c
+++ b/common/tlv-parser.c
@@ -556,10 +556,7 @@ tlv_expect_octet_string (tlv_parser_t tlv, int encapsulates,
         && (!tlv->ti.is_constructed || encapsulates)))
     return (tlv->lasterr = gpg_error (GPG_ERR_INV_OBJ));
   p = tlv->buffer;
-  n = tlv->ti.length;
-  if (!n && tlv->ti.ndef)
-    n = tlv->bufsize;
-  else if (!tlv->ti.length)
+  if (!(n=tlv->ti.length) && !tlv->ti.ndef)
     return (tlv->lasterr = gpg_error (GPG_ERR_TOO_SHORT));
 
   if (encapsulates && tlv->ti.is_constructed