cp --parents fails without reason

[Schlomo Schapiro]

Upstream bug: https://debbugs.gnu.org/cgi/bugreport.cgi?bug=63245

The following example of a copy command fails without reason:

# rm -Rf /tmp/f && mkdir /tmp/f && cp --verbose -t /tmp/f -L --preserve=all --parents /etc/apt/sources.list && echo yes ; ls -lR /tmp/f/etc/apt/sources.list /etc/apt/sources.list
/etc -> /tmp/f/etc
/etc/apt -> /tmp/f/etc/apt
'/etc/apt/sources.list' -> '/tmp/f/etc/apt/sources.list'
cp: ‘etc/apt’: No such file or directory
-rw-r--r-- 1 root root 2437 Apr 23 09:53 /etc/apt/sources.list
-rw-r--r-- 1 root root 2437 Apr 23 09:53 /tmp/f/etc/apt/sources.list
#

/tmp is on the same filesystem as /. The same on Ubuntu 22.04 works without a problem:

# rm -Rf /tmp/f && mkdir /tmp/f && cp --verbose -t /tmp/f -L --preserve=all --parents /etc/apt/sources.list && echo yes ; ls -lR /tmp/f/etc/apt/sources.list /etc/apt/sources.list
/etc -> /tmp/f/etc
/etc/apt -> /tmp/f/etc/apt
'/etc/apt/sources.list' -> '/tmp/f/etc/apt/sources.list'
yes
-rw-r--r-- 1 root root 263 Mär 26 15:20 /etc/apt/sources.list
-rw-r--r-- 1 root root 263 Mär 26 15:20 /tmp/f/etc/apt/sources.list
#

Why I omit the --preservce=all then it works without a problem:

# rm -Rf /tmp/f && mkdir /tmp/f && cp --verbose -t /tmp/f -L --parents /etc/apt/sources.list && echo yes ; ls -lR /tmp/f/etc/apt/sources.list /etc/apt/sources.list
/etc -> /tmp/f/etc
/etc/apt -> /tmp/f/etc/apt
'/etc/apt/sources.list' -> '/tmp/f/etc/apt/sources.list'
yes
-rw-r--r-- 2 root root 2437 Apr 23 09:53 /etc/apt/sources.list
-rw-r--r-- 1 root root 2437 Apr 23 11:02 /tmp/f/etc/apt/sources.list
#

Also, when I only use --preserve=mode, then it again fails:

# rm -Rf /tmp/f && mkdir /tmp/f && cp --verbose -t /tmp/f -L --preserve=mode --parents /etc/apt/sources.list && echo yes ; ls -lR /tmp/f/etc/apt/sources.list /etc/apt/sources.list
/etc -> /tmp/f/etc
/etc/apt -> /tmp/f/etc/apt
'/etc/apt/sources.list' -> '/tmp/f/etc/apt/sources.list'
cp: ‘etc/apt’: No such file or directory
-rw-r--r-- 2 root root 2437 Apr 23 09:53 /etc/apt/sources.list
-rw-r--r-- 1 root root 2437 Apr 23 11:02 /tmp/f/etc/apt/sources.list
#

Is this a bug in cp or something else?

I'm one of the maintainers of Relax-and-Recover (rear) and noticed this in https://github.com/rear/rear/issues/2972

OS Release Info:
PRETTY_NAME="Ubuntu 23.04"
NAME="Ubuntu"
VERSION_ID="23.04"
VERSION="23.04 (Lunar Lobster)"
VERSION_CODENAME=lunar
ID=ubuntu
ID_LIKE=debian
HOME_URL="https://www.ubuntu.com/"
SUPPORT_URL="https://help.ubuntu.com/"
BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/"
PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy"
UBUNTU_CODENAME=lunar
LOGO=ubuntu-logo

Coreutils version:

# cp --version
cp (GNU coreutils) 9.1

# dpkg-query -l coreutils
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name Version Architecture Description
+++-==============-============-============-=================================
ii coreutils 9.1-1ubuntu2 amd64 GNU core utilities

ProblemType: Bug
DistroRelease: Ubuntu 23.04
Package: coreutils 9.1-1ubuntu2
ProcVersionSignature: Ubuntu 6.2.0-20.20-generic 6.2.6
Uname: Linux 6.2.0-20-generic x86_64
ApportVersion: 2.26.1-0ubuntu2
Architecture: amd64
CasperMD5CheckResult: pass
Date: Sun Apr 23 10:48:56 2023
InstallationDate: Installed on 2023-04-23 (0 days ago)
InstallationMedia: Ubuntu-Server 23.04 "Lunar Lobster" - Release amd64 (20230415)
SourcePackage: coreutils
UpgradeStatus: No upgrade log present (probably fresh install)

[Schlomo Schapiro (sschapiro)]

I reported this bug upstream and somebody even provided a patch: https://debbugs.gnu.org/cgi/bugreport.cgi?bug=63245

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.