RangeError: The value of "offset" is out of range (ANR)

[ollipa]

Is there an existing issue for this?

• I have checked for existing issues https://github.com/getsentry/sentry-javascript/issues
• I have reviewed the documentation https://docs.sentry.io/
• I am using the latest SDK release https://github.com/getsentry/sentry-javascript/releases

How do you use Sentry?

Sentry Saas (sentry.io)

Which SDK are you using?

@sentry/node

SDK Version

7.74.0

Framework Version

Node v18.17.1

SDK Setup

ANR is enabled with these settings:

Sentry.enableAnrDetection({
      captureStackTrace: true,
      anrThreshold: 1000,
});

Steps to Reproduce

We enabled ANR a few days ago and this error just popped up. Not sure how to reproduce.

Expected Result

RangeError should not be raised or reported.

Actual Result

Sentry reported an issue that seems to originate from Sentry ANR related code:

RangeError: The value of "offset" is out of range. It must be >= 0 and <= 0. Received 1
  File "node:internal/errors", line 405, col 5, in new NodeError
  File "node:internal/buffer", line 88, col 9, in boundsError
  File "node:internal/buffer", line 254, col 5, in Buffer.readUInt8
  File "app:///../node_modules/@sentry/node/cjs/anr/websocket.js", line 83, col 29, in parseFrame
  File "app:///../node_modules/@sentry/node/cjs/anr/websocket.js", line 254, col 19, in WebSocketInterface._addBuffer
  File "app:///../node_modules/@sentry/node/cjs/anr/websocket.js", line 226, col 16, in WebSocketInterface._completeFrame
  File "app:///../node_modules/@sentry/node/cjs/anr/websocket.js", line 258, col 12, in WebSocketInterface._addBuffer
  File "app:///../node_modules/@sentry/node/cjs/anr/websocket.js", line 226, col 16, in WebSocketInterface._completeFrame
  File "app:///../node_modules/@sentry/node/cjs/anr/websocket.js", line 258, col 12, in WebSocketInterface._addBuffer
  File "app:///../node_modules/@sentry/node/cjs/anr/websocket.js", line 226, col 16, in WebSocketInterface._completeFrame

[AbhiPrasad]

Hey @ollipa - are you able to provide a link to the Sentry error so we can debug a little further? You can also email it to me.

From looking at the error message, it seems that we should have a condition for making sure the buffer has length > 0 before attempting to search it for a frame. Let me try PRing a fix for that!

Otherwise, how is the ANR monitoring? Did you catch any issues with it yet?

[ollipa]

@AbhiPrasad, thank you for the quick response and a fix to the issue. I sent you an email to the email address in your Github profile.

[AbhiPrasad]

Hey @ollipa, thanks for the email! I've opened two GH issue to follow up on the issues you brought up there, and backlogged them. Will update this GH issue once the release with the fix is out as well.