diff --git a/odb/transaction.c b/odb/transaction.c
index b6da4a3942..249ef4d9b7 100644
--- a/odb/transaction.c
+++ b/odb/transaction.c
@@ -18,19 +18,23 @@ int odb_transaction_begin(struct object_database *odb,
 	return ret;
 }
 
-void odb_transaction_commit(struct odb_transaction *transaction)
+int odb_transaction_commit(struct odb_transaction *transaction)
 {
+	int ret;
+
 	if (!transaction)
-		return;
+		return 0;
 
 	/*
 	 * Ensure the transaction ending matches the pending transaction.
 	 */
 	ASSERT(transaction == transaction->source->odb->transaction);
 
-	transaction->commit(transaction);
+	ret = transaction->commit(transaction);
 	transaction->source->odb->transaction = NULL;
 	free(transaction);
+
+	return ret;
 }
 
 int odb_transaction_write_object_stream(struct odb_transaction *transaction,
diff --git a/odb/transaction.h b/odb/transaction.h
index f5c43187c9..3b0a5a78e5 100644
--- a/odb/transaction.h
+++ b/odb/transaction.h
@@ -54,10 +54,11 @@ static inline void odb_transaction_begin_or_die(struct object_database *odb,
 }
 
 /*
- * Commits an ODB transaction making the written objects visible. If the
- * specified transaction is NULL, the function is a no-op.
+ * Commits an ODB transaction making the written objects visible. Returns 0 on
+ * success, a negative error code otherwise. Note that, if the specified
+ * transaction is NULL, the function is a no-op and no error is returned.
  */
-void odb_transaction_commit(struct odb_transaction *transaction);
+int odb_transaction_commit(struct odb_transaction *transaction);
 
 /*
  * Writes the object in the provided stream into the transaction. The resulting