libx11_1.6.4 bug fix

This is the Ubuntu 18.04 libx11_1.6.4 with the proposed Fix for the poll_for_response race condition bug. The bug affects the following applications and desktops i have used so far.

Desktops

• lubuntu desktop
• LXDE desktop

Applications

• Geany
• Leafpad
• pcmanfm
• Google Chrome

Leafpad Crash screenshot

Bug

Steps to reproduce

• Boot Up your PC with Ubuntu and enter the Lubuntu session.
• attach a SDHC USB reader with a media with a huge tree of directories and subdirectories.
• Navigate inside every directory and sub directory very fast, i mean it, click, click, click as fast as you can.
• At some point you get pcmanfm stuck for a while and then a crash. It can occur in a few clicks or take some time to occur.

Google chrome is also affected by this bug, always at the startup of the application, if Google chrome takes a long time to show up on screen it usually will present you with the annoying "!xcb_xlib_threads_sequence_lost" error.

Installation

The xcb_xlib_threads_sequence_lost bug has been around for a long time and if you work with Text apps like Leafpad, Geany, or any other Editor or application that you must not lose your work when this application crash, then you should try this fix. Unfortunately the latest Google-Chrome and Chromium-browser version 85 will crash but not the version 84, Firefox works just fine.

Update

Currently it is woking fine with (I think they fixed the issue with xcb_xlib_threads_sequence_lost on the browser side):

• Chromium, Version 90.0.4430.72 (Official Build) Built on Ubuntu , running on Ubuntu 18.04 (64-bit)
• Chrome, Version 90.0.4430.85 (Official Build) (64-bit)
• FireFox, 87.0 (64-bit)

Install:

sudo dpkg -i libx11-6_1.6.4-3ubuntu0.4_amd64.deb
sudo dpkg -i libx11-xcb1_1.6.4-3ubuntu0.4_amd64.deb
sudo dpkg -i libx11-data_1.6.4-3ubuntu0.4_all.deb
sudo dpkg -i libx11-doc_1.6.4-3ubuntu0.4_all.deb
sudo dpkg -i libx11-xcb-dev_1.6.4-3ubuntu0.4_amd64.deb
sudo dpkg -i libx11-dev_1.6.4-4ubuntu0.4_amd64.deb

Releases

version: 1.6.4-3ubuntu0.4 with latest SECURITY UPDATE

https://github.com/avafinger/libx11_1.6.4/releases/tag/v0.9

libx11 (2:1.6.4-3ubuntu0.3) bionic-security; urgency=medium

  * SECURITY UPDATE: integer overflow and heap overflow in XIM client
    - debian/patches/CVE-2020-14344-1.patch: fix signed length values in
      modules/im/ximcp/imRmAttr.c.
    - debian/patches/CVE-2020-14344-2.patch: fix integer overflows in
      modules/im/ximcp/imRmAttr.c.
    - debian/patches/CVE-2020-14344-3.patch: fix more unchecked lengths in
      modules/im/ximcp/imRmAttr.c.
    - debian/patches/CVE-2020-14344-4.patch: zero out buffers in functions
      in modules/im/ximcp/imDefIc.c, modules/im/ximcp/imDefIm.c.
    - debian/patches/CVE-2020-14344-5.patch: change the data_len parameter
      to CARD16 in modules/im/ximcp/imRmAttr.c.
    - debian/patches/CVE-2020-14344-6.patch: fix size calculation in
      modules/im/ximcp/imRmAttr.c.
    - debian/patches/CVE-2020-14344-7.patch: fix input clients connecting
      to server in modules/im/ximcp/imRmAttr.c.
    - CVE-2020-14344
  * SECURITY UPDATE: integer overflow and double free in locale handling
    - debian/patches/CVE-2020-14363.patch: fix an integer overflow in
      modules/om/generic/omGeneric.c.
    - CVE-2020-14363

disclaimer

While it fix the !xcb_xlib_threads_sequence_lost bug, it breaks Chrome and Chromium browser version 85. Firefox is not affected. Works with latest Browser!