Ubuntu
libvirt package

change in readlink() errno in 2.6.39 and later kernels causes FTBFS for packages with older gnulib

Bug #817187 reported by Jamie Strandboge on 2011-07-27

This bug affects 1 person

	Status	Importance	Assigned to	Milestone
libvirt (Ubuntu)	Invalid	Undecided	Unassigned
Hardy	Invalid	High	Unassigned	Ubuntu hardy-updates
Lucid	Won't Fix	High	Unassigned	Ubuntu lucid-updates
Maverick	Invalid	High	Unassigned	Ubuntu maverick-updates
Natty	Invalid	High	Unassigned	Ubuntu natty-updates
Oneiric	Invalid	Undecided	Unassigned
linux (Ubuntu)	Invalid	Undecided	Andy Whitcroft
Hardy	Invalid	Undecided	Unassigned
Lucid	Invalid	Undecided	Unassigned
Maverick	Invalid	Undecided	Unassigned
Natty	Invalid	Undecided	Unassigned
Oneiric	Invalid	Undecided	Andy Whitcroft
m4 (Debian)	Fix Released	Unknown	debbugs #630902

Bug Description

When building packages in a chroot with gnulib testcases for readlink() on a 2.6.39 (Oneiric or newer) kernel, these packages may FTBFS. This is due to the following:
http://lists.gnu.org/archive/html/bug-gnulib/2011-03/msg00308.html

"coreutils' "make check" failed on rawhide due to a kernel change
in how readlink and readlinkat treat the empty file name.
Before, they'd fail with ENOENT. Now, it's EINVAL."

This was discovered when preparing security updates for libvirt, but will affect more than libvirt, (see Debian http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=630902). For libvirt, the patch in the above bug can be applied to gnulib/tests/test-areadlink.h to get these building again on newer releases. This is SRU-worthy, as libvirt will not build once the buildds are running newer kernels. If it is not SRUd before the next security update, the security team will do it as part of their update process.

Upstream kernel commit that introduced the change: 65cfc6722361570bfe255698d9cd4dccaf47570d

See original description

Revision history for this message

Jamie Strandboge (jdstrand) wrote on 2011-07-27:

libvirt in Oneiric builds fine.

Changed in libvirt (Ubuntu Oneiric):
status:	New → Invalid
Changed in libvirt (Ubuntu Lucid):
status:	New → Triaged
importance:	Undecided → High
Changed in libvirt (Ubuntu Maverick):
status:	New → Triaged
importance:	Undecided → High
Changed in libvirt (Ubuntu Natty):
status:	New → Triaged
importance:	Undecided → High
Changed in libvirt (Ubuntu Hardy):
status:	New → Triaged
importance:	Undecided → High
Changed in linux (Ubuntu Hardy):
status:	New → Invalid
Changed in linux (Ubuntu Lucid):
status:	New → Invalid
Changed in linux (Ubuntu Maverick):
status:	New → Invalid
Changed in linux (Ubuntu Natty):
status:	New → Invalid
Changed in libvirt (Ubuntu Hardy):
milestone:	none → hardy-updates
Changed in libvirt (Ubuntu Lucid):
milestone:	none → lucid-updates
Changed in libvirt (Ubuntu Maverick):
milestone:	none → maverick-updates

Revision history for this message

Brad Figg (brad-figg) wrote on 2011-07-27: Missing required logs.

This bug is missing log files that will aid in diagnosing the problem. From a terminal window please run:

apport-collect 817187

and then change the status of the bug to 'Confirmed'.

If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.

This change has been made by an automated script, maintained by the Ubuntu Kernel Team.

Changed in linux (Ubuntu):
status:	New → Incomplete

Revision history for this message

Jamie Strandboge (jdstrand) wrote on 2011-07-27: Re: libvirt FTBFS on 2.6.39 and later kernels

This doesn't need log files. Attached is a simple reproducer.

Changed in libvirt (Ubuntu Natty):
milestone:	none → natty-updates
Changed in linux (Ubuntu Oneiric):
status:	Incomplete → Confirmed

Revision history for this message

Jamie Strandboge (jdstrand) wrote on 2011-07-27:

reduced test case Edit (518 bytes, text/plain)

summary:

- libvirt FTBFS on 2.6.39 and later kernels
+ change in readlink() errno in 2.6.39 and later kernels causes FTBFS for
+ packages with older gnulib

Jamie Strandboge (jdstrand) on 2011-07-27

description:

updated

Revision history for this message

Andy Whitcroft (apw) wrote on 2011-07-27:

This is a notty one. The behavour has indeed changed, ENOENT was the previous return and now we return EINVAL. I do not have a POSIX manual to hand, but the gist of the restriction is as below:

   Empty pathname
       In the original Unix, the empty pathname referred to the current
       directory. Nowadays POSIX decrees that an empty pathname must not be
       resolved successfully. Linux returns ENOENT in this case.

It could be argued that the new behaviour is just as valid. A change is however unhelpful. Especially as kernel behaviour is exposed in chroots.

Jamie Strandboge (jdstrand) on 2011-07-27

description:

updated

Jamie Strandboge (jdstrand) on 2011-07-27

description:	updated
description:	updated

Revision history for this message

Andy Whitcroft (apw) wrote on 2011-07-27:

A quick review of other syscalls reacting to "" as a pathname tend to now place readlink as an inconsistant outsider:

  open("", O_RDONLY) = -1 ENOENT (No such file or directory)
  chmod("", 0777) = -1 ENOENT (No such file or directory)
  readlink("", 0x7fff794533c0, 2048) = -1 EINVAL (Invalid argument)
  stat("", 0x7fff79453330) = -1 ENOENT (No such file or directory)
  rename("", "") = -1 ENOENT (No such file or directory)
  unlink("") = -1 ENOENT (No such file or directory)

Andy Whitcroft (apw) on 2011-07-27

Changed in linux (Ubuntu Oneiric):
assignee:	nobody → Andy Whitcroft (apw)
status:	Confirmed → In Progress

Revision history for this message

Kees Cook (kees) wrote on 2011-08-03:

Packages with gnulib in their source:

main:

augeas
binfmt-support
eglibc
findutils
gdb
glib2.0
groff
grub2
hello
hello-debhelper
liblouis
libpipeline
libtasn1-3
libvirt
man-db
mlocate
texinfo

universe/multiverse:

amanda
eiskaltdcpp
freedink
genparse
hivex
instantbird
libdc0
libdrizzle
liblouisxml
mpop
msmtp
z80asm

Revision history for this message

Andy Whitcroft (apw) wrote on 2011-08-04:

Have started a thread upstream to discuss this change.

Bug Watch Updater (bug-watch-updater) on 2011-08-11

Changed in m4 (Debian):
status:	Unknown → Fix Released

Revision history for this message

JC Hulce (soaringsky) wrote on 2012-05-03:

This bug affects Ubuntu 10.10, Maverick Meerkat. Maverick has reached end-of-life and is no longer supported, so I am closing the bugtask for Maverick. Please upgrade to a newer version of Ubuntu.
More information here: https://lists.ubuntu.com/archives/ubuntu-announce/2012-April/000158.html

Changed in libvirt (Ubuntu Maverick):
status:	Triaged → Invalid

Revision history for this message

dino99 (9d9) wrote on 2013-05-10:

#10

eol reached https://wiki.ubuntu.com/Releases

Changed in libvirt (Ubuntu Hardy):
status:	Triaged → Invalid
Changed in libvirt (Ubuntu Natty):
status:	Triaged → Invalid
Changed in linux (Ubuntu Oneiric):
status:	In Progress → Invalid
Changed in linux (Ubuntu):
status:	In Progress → Invalid