diff --git a/libctf/ChangeLog b/libctf/ChangeLog
index 288ad6e554..d840bc418a 100644
--- a/libctf/ChangeLog
+++ b/libctf/ChangeLog
@@ -1,3 +1,8 @@
+2020-07-22  Nick Alcock  <nick.alcock@oracle.com>
+
+	* ctf-decl.c (ctf_decl_fini): Free the cd_buf.
+	(ctf_decl_buf): Once it escapes, don't try to free it later.
+
 2020-07-22  Nick Alcock  <nick.alcock@oracle.com>
 
 	* ctf-types.c (ctf_type_aname): Print arg types here...
diff --git a/libctf/ctf-decl.c b/libctf/ctf-decl.c
index 5dcf60ab08..faf421e476 100644
--- a/libctf/ctf-decl.c
+++ b/libctf/ctf-decl.c
@@ -68,6 +68,7 @@ ctf_decl_fini (ctf_decl_t *cd)
 	  free (cdp);
 	}
     }
+  free (cd->cd_buf);
 }
 
 void
@@ -195,5 +196,7 @@ void ctf_decl_sprintf (ctf_decl_t *cd, const char *format, ...)
 
 char *ctf_decl_buf (ctf_decl_t *cd)
 {
-  return cd->cd_buf;
+  char *buf = cd->cd_buf;
+  cd->cd_buf = NULL;
+  return buf;
 }