OverlayFS with readonly NFS lower layer. Operation not supported for non-root files.
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
linux (Ubuntu) |
Expired
|
Medium
|
Unassigned |
Bug Description
Step to reproduse:
- Crete dircetory with other directories and files.
- Chown some files in this directory, set any non-root permissions.
- Export nfs share with 'ro' permissions.
- Mount nfs share.
- Mount ovrelayfs with nfs as lowerdir
- Try to read theese non-root files or directories:
Example for overlay mount:
# ls -l /var/lib/libvirt
total 16
drwx--x--x 2 root root 4096 Oct 10 07:33 boot
drwx--x--x 2 root root 4096 Oct 10 07:33 images
drwxr-x--- 3 libvirt-qemu kvm 4096 Jan 11 21:49 qemu
drwx------ 2 root root 4096 Oct 10 07:33 sanlock
# ls -l /var/lib/
ls: cannot open directory '/var/lib/
And for nfs mount:
# ls -l /rofs/var/
total 16
drwx--x--x 2 root root 4096 Oct 10 07:33 boot
drwx--x--x 2 root root 4096 Oct 10 07:33 images
drwxr-x--- 3 libvirt-qemu kvm 4096 Jan 11 21:49 qemu
drwx------ 2 root root 4096 Oct 10 07:33 sanlock
# ls -l /rofs/var/
total 4
drwxr-xr-x 3 root root 4096 Jan 11 21:49 channel
If I reset permission, it helps:
# chown libvirt-qemu:kvm /var/lib/
# ls -l /var/lib/
total 4
drwxr-xr-x 3 root root 4096 Jan 11 21:49 channel
My mounts (from /proc/mounts)
192.
overlay / overlay rw,relatime,
I tested it nfs3 and nfs4 mount, with this kenels:
# uname -a
Linux controller03 4.4.0-62-generic #83-Ubuntu SMP Wed Jan 18 14:10:15 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux
# uname -a
Linux m1c18n1 4.8.0-36-generic #36~16.04.1-Ubuntu SMP Sun Feb 5 09:39:57 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux
---
AlsaDevices:
total 0
crw-rw----+ 1 root audio 116, 1 Feb 11 2016 seq
crw-rw----+ 1 root audio 116, 33 Feb 11 2016 timer
AplayDevices: aplay: device_list:268: no soundcards found...
ApportVersion: 2.20.1-0ubuntu2.5
Architecture: amd64
ArecordDevices: arecord: device_list:268: no soundcards found...
AudioDevicesInUse: Error: [Errno 2] No such file or directory
CRDA: Error: command ['iw', 'reg', 'get'] failed with exit code 1: nl80211 not found.
DistroRelease: Ubuntu 16.04
IwConfig: Error: [Errno 2] No such file or directory
Lsusb:
Bus 001 Device 002: ID 8087:8000 Intel Corp.
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
MachineType: HP ProLiant m710p Server Cartridge
Package: linux (not installed)
PciMultimedia:
ProcEnviron:
TERM=xterm-
PATH=(custom, no user)
XDG_RUNTIME_
LANG=en_US.UTF-8
SHELL=/bin/bash
ProcFB:
ProcKernelCmdLine: BOOT_IMAGE=
ProcVersionSign
PulseList: Error: command ['pacmd', 'list'] failed with exit code 1: No PulseAudio daemon running, or not running as session daemon.
RelatedPackageV
linux-
linux-
linux-firmware 1.157.6
RfKill: Error: [Errno 2] No such file or directory
Tags: xenial
Uname: Linux 4.8.0-36-generic x86_64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups:
_MarkForUpload: True
dmi.bios.date: 04/06/2016
dmi.bios.vendor: HP
dmi.bios.version: H06
dmi.board.vendor: HP
dmi.chassis.type: 25
dmi.chassis.vendor: HP
dmi.modalias: dmi:bvnHP:
dmi.product.name: ProLiant m710p Server Cartridge
dmi.sys.vendor: HP
Changed in linux (Ubuntu): | |
status: | Incomplete → Confirmed |
This bug is missing log files that will aid in diagnosing the problem. From a terminal window please run:
apport-collect 1665921
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.