I confirm, It seems that is not overlayfs problem. The problem occurs only with glusterfs backed storage (on nfs server). I tested this internal gluster nfs server, and ganesha nfs server, nfs-kernel-server is not supported by glusterfs. With nfs-kernel-server and ext4 no any problems. Even readonly mode.
-- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1665921 Title: OverlayFS with readonly NFS lower layer. Operation not supported for non-root files. Status in linux package in Ubuntu: Incomplete 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/libvirt/qemu/ ls: cannot open directory '/var/lib/libvirt/qemu/': Operation not supported And for nfs mount: # ls -l /rofs/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 /rofs/var/lib/libvirt/qemu/ 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/libvirt/qemu # ls -l /var/lib/libvirt/qemu/ total 4 drwxr-xr-x 3 root root 4096 Jan 11 21:49 channel My mounts (from /proc/mounts) 192.168.101.61:/data/opt/ltsp/amd64 /rofs nfs ro,relatime,vers=3,rsize=1048576,wsize=1048576,namlen=255,hard,nolock,proto=tcp,port=2049,timeo=7,retrans=10,sec=sys,local_lock=all,addr=192.168.101.61 0 0 overlay / overlay rw,relatime,lowerdir=/rofs,upperdir=/cow/up,workdir=/cow/work 0 0 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-256color PATH=(custom, no user) XDG_RUNTIME_DIR=<set> LANG=en_US.UTF-8 SHELL=/bin/bash ProcFB: ProcKernelCmdLine: BOOT_IMAGE=vmlinuz-4.8.0-36-generic ro initrd=initrd.img-4.8.0-36-generic init=/sbin/init-ltsp forcepae console=tty1 console=ttyS0,9600 root=/dev/nfs boot=nfs nfsroot=/data/opt/ltsp/amd64 BOOTIF=01-94-57-a5-d3-b9-a6 ProcVersionSignature: Ubuntu 4.8.0-36.36~16.04.1-generic 4.8.11 PulseList: Error: command ['pacmd', 'list'] failed with exit code 1: No PulseAudio daemon running, or not running as session daemon. RelatedPackageVersions: linux-restricted-modules-4.8.0-36-generic N/A linux-backports-modules-4.8.0-36-generic N/A 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:bvrH06:bd04/06/2016:svnHP:pnProLiantm710pServerCartridge:pvr:rvnHP:rn:rvr:cvnHP:ct25:cvr: dmi.product.name: ProLiant m710p Server Cartridge dmi.sys.vendor: HP To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1665921/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
