Debian Bug report logs - #703012
debianutils: ischroot can no longer detect vservers

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Message #5 received at [email protected] (full text, mbox, reply):

From: Andrew Ruthven <[email protected]>

To: Debian Bug Tracking System <[email protected]>

Subject: debianutils: ischroot can no longer detect vservers

Date: Tue, 12 Mar 2013 23:12:28 +1300

[Message part 1 (text/plain, inline)]

Package: debianutils
Version: 4.3.4
Severity: important

[resubmitting as something seems to have gone wrong with creating the bug]
[third time's the charm?]

Dear Maintainer,

The ischroot code checks to see if it can access /proc/1/root to determine
if it is a running inside a chroot. Within vservers you can now read
/proc/1/root so it is no longer a sufficient test for vservers.

On newer vserver patches a better check is to look for a VxID line in
/proc/self/status.  If the line is present you're running a vserver
kernel.  If the value is 0, then you're on the physical host, anything
else means you're in a vserver.

Inside a vserver:

puck@build-sid-amd64:/$ grep VxID /proc/self/status
VxID: 12
puck@build-sid-amd64:/$ 

On the physical host:

build-servers:~$ grep VxID /proc/self/status
VxID: 0
puck@build-servers:~$ 

A patch that adds this behaviour is attached, please feel free to rewrite! Also,
method that I've supplied works for non-root users as well, but I haven't added
that support.

I've set this bug report to important as it is stopping initscripts from being
installable on a Wheezy vserver.

This is the case on Linux kernel 3.4 + 2.3.3.9 vserver patch.  The 3.2 kernel
set of patches is not affected by this change of behaviour.

Cheers!



-- System Information:
Debian Release: wheezy/sid
  APT prefers unstable
  APT policy: (500, 'unstable')
Architecture: amd64 (x86_64)

Kernel: Linux 2.6.32-28-vserver (SMP w/1 CPU core)
Locale: LANG=en_NZ.UTF-8, LC_CTYPE=POSIX (charmap=ANSI_X3.4-1968)
Shell: /bin/sh linked to /bin/dash

Versions of packages debianutils depends on:
ii  libc6           2.13-37
ii  sensible-utils  0.0.7

debianutils recommends no packages.

debianutils suggests no packages.

-- no debconf information

[ischroot.patch (text/x-patch, attachment)]

[signature.asc (application/pgp-signature, inline)]

Message #22 received at [email protected] (full text, mbox, reply):

From: Bastian Germann <[email protected]>

To: [email protected]

Subject: Re: debianutils: ischroot can no longer detect vservers

Date: Wed, 12 Jul 2023 23:37:48 +0200

Control: tags -1 wontfix moreinfo - patch

I do not see VxID on my systems. I guess there are changes in the kernel 
that made it disappear. If you still want to get an equivalent change in 
please post a patch that applies for current unstable kernel.

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