setupFsWrapper crashes on Node 24 with "Cannot convert undefined or null to object"

Preliminary Checks

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Description

When a Gatsby site with SSR or DSG routes is deployed to a read-only lambda environment (Netlify Functions, AWS Lambda, etc.) and run on Node 24, the SSR lambda crashes on first invocation with:

TypeError: Cannot convert undefined or null to object
    at hasOwnProperty (<anonymous>)
    at setupFsWrapper (/var/task/.cache/page-ssr/lambda.js:101:33)

The crash is in packages/gatsby/src/utils/page-ssr-module/lambda.ts, in the loop that copies native props from fs onto the linkfs-wrapped object.

Reproduction Link

https://gist.github.com/McLeodSean/8b541d86e3022a80b0c1b9064bf6171d

Steps to Reproduce

Added a minimal repro gist, as the issue is tightly scoped to some logic that doesn't run locally.

mkdir gatsby-ssr-node24-repro && cd gatsby-ssr-node24-repro
npm init -y
npm install fs-extra@11 linkfs@2
nvm install 24 && nvm use 24

Save as repro.js:

const fs = require('fs-extra')
const linkfs = require('linkfs')

console.log('node:', process.version)
console.log('fs-extra F_OK:', fs.F_OK) // undefined on Node 24, 0 on Node 22

linkfs.rewritableMethods.push('createWriteStream', 'createReadStream', 'rm')
const lfs = linkfs.link(fs, [['/tmp/a', '/tmp/b']])

// This is the loop from packages/gatsby/src/utils/page-ssr-module/lambda.ts
for (const key in lfs) {
  if (Object.hasOwnProperty.call(fs[key], 'native')) {
    lfs[key].native = fs[key].native
  }
}

Run:

node repro.js

Expected Result

The loop completes without throwing. fs[key].native is copied for keys where it exists, skipped where the source value is missing.

Actual Result

Crashes on Node 24 with:

TypeError: Cannot convert undefined or null to object
    at hasOwnProperty (<anonymous>)

Switching to Node 22 (nvm use 22 && node repro.js) passes without error.

Environment

System:
    OS: macOS 26.5
    CPU: (10) arm64 Apple M1 Max
    Shell: 5.9 - /bin/zsh
  Binaries:
    Node: 24.15.0 - /private/var/folders/mn/cs2hpcxs0rs14sz5z_vjjgrc0000gp/T/xfs-a7ddf2ea/node
    Yarn: 4.11.0 - /private/var/folders/mn/cs2hpcxs0rs14sz5z_vjjgrc0000gp/T/xfs-a7ddf2ea/yarn
    npm: 11.12.1 - ~/.nvm/versions/node/v24.15.0/bin/npm
  Browsers:
    Chrome: 148.0.7778.97
    Safari: 26.5

Config Flags

DEV_SSR: true
FAST_DEV: true
PRESERVE_FILE_DOWNLOAD_CACHE: true
PARALLEL_SOURCING: true