diff --git a/reftable/record.c b/reftable/record.c
index d816de6d93..82780b2d06 100644
--- a/reftable/record.c
+++ b/reftable/record.c
@@ -861,7 +861,7 @@ static int reftable_log_record_decode(void *rec, struct strbuf key,
 	if (key.len <= 9 || key.buf[key.len - 9] != 0)
 		return REFTABLE_FORMAT_ERROR;
 
-	r->refname = reftable_realloc(r->refname, key.len - 8);
+	REFTABLE_ALLOC_GROW(r->refname, key.len - 8, r->refname_cap);
 	memcpy(r->refname, key.buf, key.len - 8);
 	ts = get_be64(key.buf + key.len - 8);
 
diff --git a/reftable/reftable-record.h b/reftable/reftable-record.h
index 2659ea008c..d28f38175c 100644
--- a/reftable/reftable-record.h
+++ b/reftable/reftable-record.h
@@ -74,6 +74,7 @@ int reftable_ref_record_equal(const struct reftable_ref_record *a,
 /* reftable_log_record holds a reflog entry */
 struct reftable_log_record {
 	char *refname;
+	size_t refname_cap;
 	uint64_t update_index; /* logical timestamp of a transactional update.
 				*/