Bug 213567

Summary: Access to unmapped vmalloc pages when reading proc/kcore
Product: Red Hat Enterprise Linux 2.1 Reporter: Don Howard <dhoward>
Component: kernelAssignee: Don Howard <dhoward>
Status: CLOSED ERRATA QA Contact: Brian Brock <bbrock>
Severity: medium Docs Contact:
Priority: medium    
Version: 2.1   
Target Milestone: ---   
Target Release: ---   
Hardware: i386   
OS: Linux   
Whiteboard:
Fixed In Version: RHSA-2007-0013 Doc Type: Bug Fix
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Clone Of: Environment:
Last Closed: 2007-01-17 10:15:16 UTC Type: ---
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
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Description Flags
Don't use vmalloc in proc_file_read(). none

Description Don Howard 2006-11-02 00:17:55 UTC 
While testing patches for BZ #14766 I found that 2.1 crashes reliably when more
than one process reads /proc/kcore:

$ while true; do cat /proc/kcore > /tmp/kcore; done&
$ while true; do cat /proc/kcore > /dev/null; done&

Derry, RHEL3, and later don't exhibit this problem.
Comment 1 Don Howard 2006-11-02 00:21:16 UTC 
Created attachment 140058 [details]
Don't use vmalloc in proc_file_read().
Comment 4 Mike Gahagan 2006-12-19 19:59:19 UTC 
I couldn't recreate the crash with e.70, however I have verified that the fix is
in as part of linux-2.4.26-updates.patch and that patch is being applied in e.71.
Comment 6 Red Hat Bugzilla 2007-01-17 10:15:16 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.

http://rhn.redhat.com/errata/RHSA-2007-0013.html