Pkg xen devel - Oct 2013 - Bug#727100: domain doesn't reboot with xl toolstack

Package: xen-utils-4.1
Version: 4.1.4-3+deb7u1
Severity: important
Tags: security patch

When you use xl toolstack, you can't reboot domUs.
When you switch back to xm toolstack, than reboot works again.
I think the problem with the debian packaged version is the same as in
this thread:
http://lists.xen.org/archives/html/xen-devel/2011-09/msg01289.html
I also think it's a security issue, since this is kind of a DoS from
the viewpoint of a domU.
In that thread, Ian Campbel also provided a patch, which might work
for the debian version too. (I haven't tested yet.)

Cheers,
Gy?rgy P?SZTOR

-- System Information:
Debian Release: 7.2
  APT prefers stable-updates
  APT policy: (500, 'stable-updates'), (500, 'stable')
Architecture: amd64 (x86_64)

Kernel: Linux 3.2.0-4-amd64 (SMP w/8 CPU cores)
Locale: LANG=hu_HU.UTF-8, LC_CTYPE=hu_HU.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages xen-utils-4.1 depends on:
ii  e2fslibs          1.42.5-1.1
ii  libc6             2.13-38
ii  libgnutls26       2.12.20-7
ii  libncurses5       5.9-10
ii  libpci3           1:3.1.9-6
ii  libtinfo5         5.9-10
ii  libuuid1          2.20.1-5.3
ii  libxen-4.1        4.1.4-3+deb7u1
ii  libxenstore3.0    4.1.4-3+deb7u1
ii  python            2.7.3-4+deb7u1
ii  python2.7         2.7.3-6
ii  xen-utils-common  4.1.4-3+deb7u1
ii  zlib1g            1:1.2.7.dfsg-13

Versions of packages xen-utils-4.1 recommends:
ii  bridge-utils                                   1.5-6
ii  qemu-keymaps                                   1.1.2+dfsg-6a
ii  qemu-utils                                     1.1.2+dfsg-6a
ii  xen-hypervisor-4.1-amd64 [xen-hypervisor-4.1]  4.1.4-3+deb7u1

Versions of packages xen-utils-4.1 suggests:
pn  xen-docs-4.1  <none>

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On Tue, 2013-10-22 at 11:52 +0200, PASZTOR Gyorgy wrote:
> When you use xl toolstack, you can't reboot domUs.
> When you switch back to xm toolstack, than reboot works again.
> I think the problem with the debian packaged version is the same as in
> this thread:
> http://lists.xen.org/archives/html/xen-devel/2011-09/msg01289.html
> I also think it's a security issue, since this is kind of a DoS from
> the viewpoint of a domU.
The only people who can migrate a domain in any sensible deployment
would be host administrator or maybe the VM admin. So there is no
security aspect since they already more than privileged enough to simply
destroy the domain if they wanted.

The status of xl in 4.1 was "try it and if it works for you great,
otherwise stick with xm". This particular issue is already fixed in
newer Xen, which is good.

FWIW this was fixed by git commit 062ef262f9df upstream. Looks like it
was fixed in 4.2-rc1.

Hi,

"Ian Campbell" <ijc at hellion.org.uk> ?rta 2013-10-22
11:17-kor:
> On Tue, 2013-10-22 at 11:52 +0200, PASZTOR Gyorgy wrote:
> > When you use xl toolstack, you can't reboot domUs.
> > When you switch back to xm toolstack, than reboot works again.
> > I think the problem with the debian packaged version is the same as in
> > this thread:
> > http://lists.xen.org/archives/html/xen-devel/2011-09/msg01289.html
> > I also think it's a security issue, since this is kind of a DoS
from
> > the viewpoint of a domU.
> 
> The only people who can migrate a domain in any sensible deployment
> would be host administrator or maybe the VM admin. So there is no
> security aspect since they already more than privileged enough to simply
> destroy the domain if they wanted.
I didn't mention migrate, I wrote about reboot.
However if the domU's admin don't have host admin right's, just want
to
reboot, then it'll fail, and his machine will remain shut down, until host
admin starts it again... What is this, if not a denial of a service?

PS.: I understand that 4.1/xl is just 'try and use if works' in Debian
7.0,
but if your patch works, I don't see a reason, why it couldn't applied,
and
pushed through proposed-updates, and if a wider userbase tested it, it
could be incorporated into the next point release of Wheezy.

Cheers,
Gy?rgy

Your message dated Sun, 10 Aug 2014 12:00:17 +0000
with message-id <E1XGRnN-0007aq-75 at franck.debian.org>
and subject line Bug#727100: fixed in xen 4.4.0-1
has caused the Debian Bug report #727100,
regarding domain doesn't reboot with xl toolstack
to be marked as done.

This means that you claim that the problem has been dealt with.
If this is not the case it is now your responsibility to reopen the
Bug report if necessary, and/or fix the problem forthwith.

(NB: If you are a system administrator and have no idea what this
message is talking about, this may indicate a serious mail system
misconfiguration somewhere. Please contact owner at bugs.debian.org
immediately.)


-- 
727100: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=727100
Debian Bug Tracking System
Contact owner at bugs.debian.org with problems
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