Bug 170398 – [GTK] WebKitWebProcess crashes with SIGBUS

• Component: WebKitGTK
• Status: RESOLVED WORKSFORME

[Luka Napotnik]

Created attachment 306069 [details]
full gdb backtrace of WebKitWebProcess

Hello,

I'm running a gtk3 app inside an Ubuntu docker container that load a page via WebKit and creates a snapshot of it.

The problem I have is that in some web pages, the app would terminate with a SIGBUS signal. I've provided an attachment with the apps backtrace. The interesting thing is that the exact same app doesn't fail on the host system that much often as it does when inside Docker

Software used:
- x86-64 Ubuntu 16.04.1 on host
- phusion/baseimage as container baseimage 
- Docker 1.12.3
- a build of webkitgtk 2.14.4
- cairo master @ cffa452f44eadebef8553502e3d6cc49829d38ce

[Michael Catanzaro]

That's really deep in cairo, so I bet it's a cairo issue?

[Luka Napotnik]

Is it possible that cairo is accessing webkit shared memory that was already destroyed by webkit, hence the SIGBUS signal?

[Michael Catanzaro]

Maybe. Can you install WebKit debuginfo and attach a new backtrace? Do you have a web page that often reproduces this crash?

[Luka Napotnik]

Hi.

It seems that the small /dev/shm that's 64MB in docker caused a problem when dealing with shared memory.

Increasing it to 1GB via '-shm-size 1GB' fixed the issue.

Closing.