[Bug-cpio] Strange CPIO behavior with links

[John Worley]

Hi -

    I recently found some strange CPIO behavior. I have a process
that starts with the IANA time-zone database releases, part of which
is creating a CPIO archive from the etc/zoneinfo directory extracted
from each release.

    The process worked fine until the 2017c release, where we started
getting errors in the UTC timezone. I tracked it down to the following:
when the archive is created by version 2.11, the restored directory has
bad links, even if extracted by earlier (2.9) and later (2.12) versions.

    I've attached the following files:

    original.tar.gz      A gzip'd tar of the original directory (zoneinfo)
    createIt             A bash script to generate an archive with a
                         specific cpio executable
    archive2-11.cpio.gz  A gzip'd cpio archive created by CPIO 2.11
    archive2-12.cpio.gz  A gzip'd cpio archive created by CPIO 2.12

    For each CPIO archive, I extract as follows:

        gunzip < archive.cpio.gz | cpio -iBdum --quiet

    When archive2-11.cpio.gz is used, you can see the bad links
as follows:

bash> find zoneinfo --samefile zoneinfo/GMT
zoneinfo/America/Argentina/Buenos_Aires   ???
zoneinfo/America/Buenos_Aires             ???
zoneinfo/GMT0
zoneinfo/GMT-0
zoneinfo/Greenwich
zoneinfo/Etc/GMT0
zoneinfo/Etc/GMT-0
zoneinfo/Etc/Greenwich
zoneinfo/Etc/GMT
zoneinfo/Etc/GMT+0
zoneinfo/GMT
zoneinfo/GMT+0

    Clearly, the time-zone information for Buenos Aires shouldn't
be linked to GMT. However, if archive2-12.cpio.gz is used, the
expected linkages are there.

    This occurs on both ext3 and ext4 file systems.

    Please let me know if you need any additional information.

--

createIt
Description: Text document

archive2-12.cpio.gz
Description: GNU Zip compressed data

archive2-11.cpio.gz
Description: GNU Zip compressed data

original.tar.gz
Description: GNU Zip compressed data

smime.p7s
Description: S/MIME Cryptographic Signature