136aefd2f6
do_fchmod () and do_chmod () used to call override_mode () directly to retrieve the owner information, but the usage of override_mode () was wrong; override_mode () expects struct stat is already populated by the information provided by the underlying filesystem, but do_fchmod () and do_chmod () only zeroed st_uid and st_gid. override_mode () does not update the owner information when st_mode is not S_IFDIR nor S_IFREG so this caused chmod to change the file owner to root at random. Use the logic rpl_stat () employs to file owner retrieval for chmod functions to ensure they provide the owner information consistent with rpl_stat (). Signed-off-by: Akihiko Odaki <odaki@rsg.ci.i.u-tokyo.ac.jp>
fuse-overlayfs
An implementation of overlay+shiftfs in FUSE for rootless containers.
Usage:
$ fuse-overlayfs -o lowerdir=lowerdir/a:lowerdir/b,upperdir=up,workdir=workdir merged
Specify a different UID/GID mapping:
$ fuse-overlayfs -o uidmapping=0:10:100:100:10000:2000,gidmapping=0:10:100:100:10000:2000,lowerdir=lowerdir/a:lowerdir/b,upperdir=up,workdir=workdir merged
Requirements:
If you are not using the static build as explained in the next chapter, your system needs libfuse > v3.2.1.
- On Fedora:
dnf install fuse3-devel - On Ubuntu > v19.04:
apt install libfuse3-dev
Also, please note that, when using fuse-overlayfs from a user namespace
(for example, when using rootless podman) a Linux Kernel > v4.18.0 is required.
Static Build:
This project provides a convenient way to automatically perform a static build using a container. The result is a self-contained binary without dependencies, that can be copied across hosts.
-
Install
buildahas explained here; -
Both the build and deploy host require the special device
/dev/fuse; there are a few ways to obtain it:
- install
fuse2orfuse3using the package manager of your choice (dnf, apt, pacman, etc): the install script will usually create the device automatically; or - manually create the device with the command
mknod /dev/fuse -m 0666 c 10 229(see this code)
-
Clone this repository, and switch to the top-level folder containing the file "
Containerfile.static.ubuntu"; -
Launch the build with the command (note the single dot
.at the end):
buildah bud -v $PWD:/build/fuse-overlayfs -t fuse-overlayfs -f ./Containerfile.static.ubuntu .
- Copy the resulting binary to your host:
sudo cp fuse-overlayfs /usr/bin/