Image Upload with Resizing causes Filesystem overflow

Description:

When we upload an image that needs to be resized the upload hangs at 0% in the UI and our filesystem fills itself to 100% because of a broken file descriptor it seems. The issue was persistent when GraphicsMagick was used and we hoped it would be fixed when switching to the sharp module but it is still happening. We are using StorageType FileSystem for the uploads and Avatar resizing is activated.

Server Setup Information:

• Version of Rocket.Chat Server: 0.62.2
• Operating System: RHEL 7.4 3.10.0-693.21.1.el7.x86_64
• Deployment Method(snap/docker/tar/etc): tar
• Number of Running Instances: 1
• DB Replicaset Oplog: Disabled
• Node Version: 8.9.3
• mongoDB Version: 2.6.12-1
• StorageType: FileSystem

Steps to Reproduce:

1. Start image upload that needs to be resized by the server, extension/file type doesn't matter - same problem with avatar upload

Scenario that breaks the upload and fills the filesystem:
Fileupload Storage Type: Filesystem
Filesystem Path: /tmp/ufs (this is linked in the filesystem to /var/rc_fileupload)
Avatar Resize: False
Set Default Avatar: False

Expected behavior:

Image is uploaded, resized and shown in UI

Actual behavior:

Filesystem overflow

Relevant logs:

rocketchat.log

Browser Logs:
Browser just gets a timeout here.

No source file, test, or entry point is named. Start by reproducing a resized image upload with filesystem storage and inspect the server logs and server-side upload and resize flow; done means the upload completes, the resized image appears in the UI, and repeated failures no longer fill the filesystem.