Bug 231775

Summary:	app-shells/bash-3.2 tty session leader (tcsetpgrp) race condition
Product:	Gentoo Linux	Reporter:	Joe Peterson (RETIRED) <lavajoe>
Component:	[OLD] Core system	Assignee:	Gentoo's Team for Core System packages <base-system>
Status:	RESOLVED FIXED
Severity:	normal
Priority:	High
Version:	unspecified
Hardware:	All
OS:	Linux
Whiteboard:
Package list:		Runtime testing required:	---
Attachments:	Patch to fix the race condition (stop parent from stealing child session leader status)

Description Joe Peterson (RETIRED) gentoo-dev

2008-07-14 15:52:54 UTC

A parent bash shell sometimes will set the session leader tty (using tcsetpgrp) back to itself, taking control away from a child bash shell, due to a race condition.  A result is that the child can then not then execute some commands (like stty) from its init script (e.g. .bashrc).  The result I (and others) have seen is that the bash shell will hang while reading the init script.

As far as I know (from some old posts I've seen), this is a long-standing intermittent issue.  I reported this on the bash bug list, and I received a patch from upstream that fixes it.  Upstream says this will likely make it into bash-4.0.  I will attach the patch, in case we want to apply it in Gentoo to fix the issue in current builds.

More info is here:

http://www.nabble.com/stty-sometimes-hangs-(ERESTARTSYS-error)-when-called-from-.bashrc-td18047733.html#a18305346

Comment 1 Joe Peterson (RETIRED) gentoo-dev

2008-07-14 15:54:18 UTC

Created attachment 160351 [details, diff]
Patch to fix the race condition (stop parent from stealing child session leader status)

Comment 2 SpanKY gentoo-dev

2009-02-09 01:07:42 UTC

added to bash-3.2_p48-r1