Activity log for bug #1662880

Date Who What changed Old value New value Message
2017-02-08 12:49:59 Luke bug added bug
2017-02-08 12:50:15 Luke description Host system mounts an encrypted directory with the '--public' under the root shell to the /folder mountpoint. Then an unprivileged LXC container bind mounts the folder using the 'mount.entry' option. LXC container runs with uid/gid mapping so that root user inside the container has uid=100000/gid=100000 and respectively, the www-data user inside LXC has uid=1000333/gid=1000333. The mountpoint /folder permissions are set (on the host) like so: chown 100000:100033 /folder chmod 0770 /folder Inside the container the local root user has write permissions and can create any object. The www-data user inside LXC seems also to have write access but unexpectedly has issues: cd /folder => OK test -w /folder && echo OK => OK touch /folder/file => Access denied The same configuration except when the /folder is not a encfs-mount works perfectly. Some other weird issues exist when the LXC local user is a member of several groups but the folder is not the main gid of the user. For instance, "touch" and "mkdir" work but "ln -s" does not. Host system mounts an encrypted directory with the '--public' flag under the root shell to the /folder mountpoint. Then an unprivileged LXC container bind mounts the folder using the 'mount.entry' option. LXC container runs with uid/gid mapping so that root user inside the container has uid=100000/gid=100000 and respectively, the www-data user inside LXC has uid=1000333/gid=1000333. The mountpoint /folder permissions are set (on the host) like so: chown 100000:100033 /folder chmod 0770 /folder Inside the container the local root user has write permissions and can create any object. The www-data user inside LXC seems also to have write access but unexpectedly has issues: cd /folder => OK test -w /folder && echo OK => OK touch /folder/file => Access denied The same configuration except when the /folder is not a encfs-mount works perfectly. Some other weird issues exist when the LXC local user is a member of several groups but the folder is not the main gid of the user. For instance, "touch" and "mkdir" work but "ln -s" does not.
2017-02-08 12:52:52 Luke description Host system mounts an encrypted directory with the '--public' flag under the root shell to the /folder mountpoint. Then an unprivileged LXC container bind mounts the folder using the 'mount.entry' option. LXC container runs with uid/gid mapping so that root user inside the container has uid=100000/gid=100000 and respectively, the www-data user inside LXC has uid=1000333/gid=1000333. The mountpoint /folder permissions are set (on the host) like so: chown 100000:100033 /folder chmod 0770 /folder Inside the container the local root user has write permissions and can create any object. The www-data user inside LXC seems also to have write access but unexpectedly has issues: cd /folder => OK test -w /folder && echo OK => OK touch /folder/file => Access denied The same configuration except when the /folder is not a encfs-mount works perfectly. Some other weird issues exist when the LXC local user is a member of several groups but the folder is not the main gid of the user. For instance, "touch" and "mkdir" work but "ln -s" does not. Host system mounts an encrypted directory with the '--public' flag under the root shell to the /folder mountpoint. Then an unprivileged LXC container bind mounts the folder using the 'mount.entry' option. LXC container runs with uid/gid mapping so that root user inside the container has uid=100000/gid=100000 and respectively, the www-data user inside LXC has uid=1000333/gid=1000333. The mountpoint /folder permissions are set (on the host) like so: chown 100000:100033 /folder chmod 0770 /folder Inside the container the local root user has write permissions and can create any object. The www-data user inside LXC seems also to have write access but unexpectedly has issues: cd /folder => OK test -w /folder && echo OK => OK touch /folder/file => Access denied The same configuration except when the /folder is not a encfs-mount works perfectly. Some other weird issues exist when the LXC local user is a member of several groups but the folder is not the main gid of the user but one of the supplemental groups. For instance, "touch" and "mkdir" work but "ln -s" does not.