Bug 157260

Summary: a certain command makes bash coredump
Product: Red Hat Enterprise Linux 4 Reporter: John Smith <johnsmith7219>
Component: bashAssignee: Tim Waugh <twaugh>
Status: CLOSED ERRATA QA Contact: Ben Levenson <benl>
Severity: high Docs Contact:
Priority: low    
Version: 4.0   
Target Milestone: ---   
Target Release: ---   
Hardware: i386   
OS: Linux   
Fixed In Version: RHBA-2006-0332 Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2006-08-10 21:16:33 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Bug Depends On:    
Bug Blocks: 181409    
Description Flags
backtrace none

Description John Smith 2005-05-09 21:36:23 UTC
From Bugzilla Helper:
User-Agent: Mozilla/5.0 (X11; U; Linux i686; rv:1.7.7) Gecko/20050417 Fedora/1.7.7-1.3.1

Description of problem:
The following command makes bash coredump.

Version-Release number of selected component (if applicable):

How reproducible:

Steps to Reproduce:
cat <$(cat $(which bash))

Actual Results:  Segmentation fault

Expected Results:  No segmentation fault

Additional info:

Comment 1 Tim Waugh 2005-05-10 08:34:08 UTC
With bash-3.0-30 (Fedora devel) on x86_64 I get this:

$ cat <$(cat $(which bash))
bash: $(cat $(which bash)): ambiguous redirect

so it's possible it's fixed since Fedora Core 3.  However, I'd like to be sure.

Please install the bash-debuginfo-3.0-18 package from


and then run bash like this:

At the $ prompt: gdb bash
At the (gdb) prompt: run

Then type your command and make it crash.  Then get the strack trace like this:

At the (gdb) prompt: bt

What does it say?

Comment 2 John Smith 2005-05-10 11:45:05 UTC
Actually, it's a bit strange, I said that bash coredumps but
it's still running afterwards.  Here's what happens:

$ echo $SHELL $$
/bin/bash 4670
$ ls
$ ulimit -c 10000
$ cat <$(cat $(which bash))
Segmentation fault (core dumped)
$ echo $SHELL $$
/bin/bash 4670
$ ls
$ file core.4730 
core.4730: ELF 32-bit LSB core file Intel 80386, version 1 (SYSV), SVR4-style,
SVR4-style, from 'bash'

The core does come from bash.  I don't know what exactly happens
when the crashing command gets executed but the initial bash does
not crash, so when I apply your recipe, I don't get the gdb prompt
back (unless of course I exit from bash, in which case there is no

Comment 3 Tim Waugh 2005-05-10 13:02:19 UTC
I expect that it's one of the sub-processes that sefaults then.  Please do this:

gdb /bin/bash core.4730

and then enter 'bt' at the (gdb) prompt.  Thanks.

Comment 4 John Smith 2005-05-10 13:49:42 UTC
Created attachment 114203 [details]

OK, attached is the output of gdb.

Comment 5 Tim Waugh 2005-05-10 14:53:35 UTC

Comment 6 Tim Waugh 2005-05-10 16:10:50 UTC
Okay, I see it here too on a different machine.  The multibyteifs patch had a
small bug.

Fixed in 3.0-31 in Fedora development.  Thanks for the report.

Comment 18 Bob Johnson 2006-04-11 17:09:31 UTC
This issue is on Red Hat Engineering's list of planned work items 
for the upcoming Red Hat Enterprise Linux 4.4 release.  Engineering 
resources have been assigned and barring unforeseen circumstances, Red 
Hat intends to include this item in the 4.4 release.

Comment 22 Red Hat Bugzilla 2006-08-10 21:16:33 UTC
An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on the solution and/or where to find the updated files,
please follow the link below. You may reopen this bug report
if the solution does not work for you.