Use of BINARY Parameter w/Stored Procedure Call Corrupts the Node Process

[David Russo]

Describe the bug
Calling a stored procedure with a binary parameter corrupts the Node process. The problem manifests itself in different ways depending on the program. For example, the process may crash with a segmentation fault.

To Reproduce
Steps to reproduce the behavior:

1. This simple example will reproduce the problem and crash the Node process with a segmentation fault.
2. Create this SQL stored procedure on the IBM i system:

create or replace procedure yourlib.testbin
(
  in bin_data binary(16),
  out char_data char(1)
)
specific yourlib/testbin
language sql
set char_data = '1'

3. Run this Node.js program:

"use strict";

const db2i = require("idb-connector");
const util = require("util");

(async () => {

  let dbconn;
  try {
    dbconn = new db2i.dbconn();
    dbconn.conn("*LOCAL");
    for (let i = 0; i < 1000; i++)
      console.log(i, await call());
  }
  catch (error) {
    console.error(error);
  }
  finally {
    dbconn.disconn();
    dbconn.close();
    process.exit(0);
  }

  async function call() {
    let dbstmt = new db2i.dbstmt(dbconn);
    try {
      await util.promisify(dbstmt.prepare).bind(dbstmt)("call yourlib.testbin(?,?)");
      await util.promisify(dbstmt.bindParam).bind(dbstmt)([
        [Buffer.alloc(16), db2i.IN, db2i.BINARY],
        [null, db2i.OUT, db2i.CHAR]
      ]);
      const output = await new Promise((resolve, reject) => {
        dbstmt.execute((outputParams, error) => {
          if (error)
            reject(error);
          else
            resolve(outputParams);
        });
      });
      return output;
    }
    finally {
      dbstmt.close();
    }
  
  }

})();

4. After usually 5-6 repetitions, the process will crash with output like this:

0 [ '1' ]
1 [ '1' ]
2 [ '1' ]
3 [ '1' ]
4 [ '1' ]
5 [ '1' ]
6 [ '1' ]


#
# Fatal error in , line 0
# Check failed: result.second.
#
#
#
#FailureMessage Object: fffffffffffe510
Trace/BPT trap (core dumped)

• Node.js version: v14.18.1
• idb-connector version: 1.2.13
• IBM i version:: 7.3

The same problem affects BLOB parameters.

As I mentioned above, the problem can manifest in different ways depending on the program. I originally encountered this issue in an HTTP/Express server application. In that case the process produces output like above, but doesn't crash. Instead it remains running, but appears to be stuck in a loop or something -- it runs with high CPU, stops responding to requests, and stays that way until killed with ENDJOB.

I'm guessing that something in idb-connector native code is writing into memory that doesn't belong to it, which corrupts the process in unpredictable ways.

I noticed this commit, which skips the blob/binary tests:

b02cd36

[github-actions]

👋 Hi! This issue has been marked stale due to inactivity. If no further activity occurs, it will automatically be closed.

[David Russo]

Please keep this active.

[Korinne Adler]

@abmusse can you please add keep-open rules to our stale bot config?