`child_process.spawnSync` may results an abort

[zyscoder]

• Version: v14.15.1
• Platform: Linux 5.8.0-38-generic The binary and long term compatibility with node #43~20.04.1-Ubuntu SMP Tue Jan 12 16:39:47 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux
• Subsystem: process

What steps will reproduce the bug?

Setup a node instance,

» node

and run the following javascript code.

new tty.ReadStream(4);
child_process.spawnSync('str');

Then the node instance occurs an abort.
In my practice, the only value "4" results in the abort.

How often does it reproduce? Is there a required condition?

This abort can always be triggered following the steps above.

What is the expected behavior?

I noticed that nodejs docs say "In normal circumstances process.stdin will be the only tty.ReadStream instance in a Node.js process and there should be no reason to create additional instances.". Maybe some limitation for users to construct a tty.ReadStream is needed. If any error occurs, an exception or other similar error-reporting stuff should be thrown. There is no reason to abort the whole node process.

What do you see instead?

» node
Welcome to Node.js v14.15.1.
Type ".help" for more information.
> new tty.ReadStream(4);
<ref *1> ReadStream {
 ...
}
> child_process.spawnSync('str');
[2]    2461977 abort      node                                                                                                                                                                                      

Additional information

[Ayase-252]

Refs: #37780 #38021

Is using these constructors of both tty.ReadStream or tty.createStream illegal in userland?

[addaleax]

This is basically of the same kind as #37874, you’re interfering with an fd owned by libuv and see a crash as a consequence of that, not really surprising and not really something that you should do in any case.

Is using these constructors of both tty.ReadStream or tty.createStream illegal in userland?

No.

[yashLadha]

@addaleax If there is no AI can we close this issue.