>From your bug:
"Windows can still be bought to front by clicking them, but never gain focus 
and no application (besides nautlilus I guess, which is stalled) receives 
clicks or keystrokes."

This sounds like nautilus has grabbed mouse & keyboard when it started
drag & drop operation. From what I know it is perfectly valid action on
X. Any app can grab keyboard and/or mouse...

https://freedesktop.org/wiki/Specifications/XDND/
Read "Protecting against malfunctioning programs" section. It seems that it is 
application responsibility to make sure it does not crash and/or lock (doesn't 
wait forever).

Reading your bug seems that nautilus just enters in "waiting forever"
state when sftp connection drops. It just waits for something that will
never happen and also does not ungrab keyboard and/or mouse. Yes, that
is bad, very bad situation...

But I don't see how this could be fixed somewhere else. Metacity (window
manager) is not involved here, also I think there is nothing to fix in
X. How can X know that application has entered some bad state?

Nautilus most likely can detect that connection drops and in such case
it must make sure that any started drag & drop operation is cancelled.
If that happens with other apps, then it might be bug at toolkit level -
gtk+.

Can you provide steps how to reproduce this bug?

Might be good idea to forward bug to upstream project:
https://gitlab.gnome.org/GNOME/nautilus

Maybe nautilus developers has already fixed this in newer versions. My
16.04 installations shows 1:3.18.4.is.3.14.3-0ubuntu6 as nautilus
version which is very old version.

-- 
You received this bug notification because you are a member of Desktop
Packages, which is subscribed to nautilus in Ubuntu.
https://bugs.launchpad.net/bugs/1741902

Title:
  Drag and drop state may be freezed by rogue application

Status in metacity package in Ubuntu:
  New
Status in nautilus package in Ubuntu:
  New

Bug description:
  I had some issues with nautlilus in the past time, that of cause need
  to be resolved by the nautlilus devs, but it turns out that IO freezes
  (eg. dropped sftp connections) may freeze nautlilus while drag and
  drop operations, and hence freeze metacity in some kind, as d&d seems
  to lock some control to the participating applications.

  What I do:

  Drag a file from nautilus.

  What happens:

  Nautilus blocks for some reason, eg. dropped sftp connection. The
  mouse pointer stays in dragging state after releasing the mouse
  button. No drop action is executed. Windows can still be bought to
  front by clicking them, but never gain focus and no application
  (besides nautlilus I guess, which is stalled) receives clicks or
  keystrokes. If at some point nautilus crashes in turn, the system
  usability is fully restored. If not, a restart by hard shutdown is
  needed to regain control.

  What should happen:

  If an application fails to commence it's drag and drop interaction,
  the action should be canceled on metacity's behalf. Otherwise any
  rogue application can stop user interaction down to moving the pointer
  around, requiring hard reboot.

  Security considerations:

  Low. The freezed state seems to block screen locking, and may reveal
  an unprotected desktop if the rogue application releases control at
  some point, eg. by crashing.

  ProblemType: Bug
  DistroRelease: Ubuntu 16.04
  Package: metacity 1:3.18.7-0ubuntu0.3
  ProcVersionSignature: Ubuntu 4.4.0-105.128-generic 4.4.98
  Uname: Linux 4.4.0-105-generic x86_64
  ApportVersion: 2.20.1-0ubuntu2.15
  Architecture: amd64
  CurrentDesktop: GNOME-Flashback:Unity
  Date: Mon Jan  8 14:52:41 2018
  EcryptfsInUse: Yes
  InstallationDate: Installed on 2016-08-23 (503 days ago)
  InstallationMedia: Ubuntu 16.04.1 LTS "Xenial Xerus" - Release amd64 
(20160719)
  SourcePackage: metacity
  UpgradeStatus: No upgrade log present (probably fresh install)

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/metacity/+bug/1741902/+subscriptions

-- 
Mailing list: https://launchpad.net/~desktop-packages
Post to     : [email protected]
Unsubscribe : https://launchpad.net/~desktop-packages
More help   : https://help.launchpad.net/ListHelp

Reply via email to