[Bug 672943] Re: virt-aa-helper crashes on random parts

[Jamie Strandboge]

I can confirm this on lucid:
$ /usr/lib/libvirt/virt-aa-helper -u libvirt-14412844-e1d1-4dfc-ad03-6adf185fa243 -c --dryrun < /tmp/xml

As mentioned, this is due to random_r crashing. In virt-aa-helper on
Lucid, this is triggered by the call to virDomainDefParseXML(), which
calls virUUIDGenerate(), which eventually calls virRandom() and then
random_r(). The problem is that virRandom() is called, but virt-aa-
helper never calls virRandomInitialize() (like is done in libvirt.c).

On maverick (libvirt 0.8.3), the original reproducer XML is considered
invalid. Attached is XML that should trigger the flaw  there as well,
but only if /dev/urandom cannot by opened. The behavior changed because
of:

commit 28024f2311462d7f836e9f90aea805d1861b2abe
Author: Laine Stump <laine at laine.org>
Date:   Mon Jan 11 10:05:38 2010 +0100

    Fix UUID random generator to use /dev/random
    
    Only use pseudo-random generator for uuid if using /dev/random fails.
    * src/util/uuid.c: The original code. would only print the warning
      message if using /dev/random failed, but would still go ahead and call
      virUUIDGeneratePseudoRandomBytes in all cases anyway.

So the reproducer is now:
$ sudo chmod 660 /dev/urandom
$ cat /tmp/672943.xml | /usr/lib/libvirt/virt-aa-helper -c -u libvirt-7d781722-69b7-8801-fe96-caf37b7a8968 --dryrun
...
Segmentation fault
$ sudo chmod 666 /dev/urandom

** Attachment added: "672943.xml"
   https://bugs.launchpad.net/ubuntu/lucid/+source/libvirt/+bug/672943/+attachment/1728108/+files/672943.xml

** Changed in: libvirt (Ubuntu Lucid)
       Status: Confirmed => Triaged

** Changed in: libvirt (Ubuntu Maverick)
       Status: Invalid => Triaged

** Changed in: libvirt (Ubuntu Natty)
       Status: Invalid => Triaged

-- 
virt-aa-helper crashes when domain XML does not contain <uuid>
https://bugs.launchpad.net/bugs/672943
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