mirror of
https://github.com/containers/podman.git
synced 2025-06-04 21:55:24 +08:00
d2e10a71d6
In case the command inside the podman unshare env failed podman unshare always exits with 125 and prints `Error: exit status 125`. This is a bad user experience and makes it difficult to use in scripts which could expect certain exit codes. This commit makes sure podman unshare uses the same exit code as the command and does not print the useless `exit status X` message. Also to match podman run/exec it should return 126 for EPERM and 127 for ENOENT. Signed-off-by: Paul Holzinger <pholzing@redhat.com>
109 lines
4.1 KiB
Markdown
109 lines
4.1 KiB
Markdown
% podman-unshare(1)
|
|
|
|
## NAME
|
|
podman\-unshare - Run a command inside of a modified user namespace
|
|
|
|
## SYNOPSIS
|
|
**podman unshare** [*--*] [*command*]
|
|
|
|
## DESCRIPTION
|
|
Launches a process (by default, *$SHELL*) in a new user namespace. The user
|
|
namespace is configured so that the invoking user's UID and primary GID appear
|
|
to be UID 0 and GID 0, respectively. Any ranges which match that user and
|
|
group in `/etc/subuid` and `/etc/subgid` are also mapped in as themselves with the
|
|
help of the *newuidmap(1)* and *newgidmap(1)* helpers.
|
|
|
|
**podman unshare** is useful for troubleshooting unprivileged operations and for
|
|
manually clearing storage and other data related to images and containers.
|
|
|
|
It is also useful if you want to use the **podman mount** command. If an unprivileged user wants to mount and work with a container, then they need to execute
|
|
**podman unshare**. Executing **podman mount** fails for unprivileged users unless the user is running inside a **podman unshare** session.
|
|
|
|
The unshare session defines two environment variables:
|
|
|
|
- **CONTAINERS_GRAPHROOT**: the path to the persistent container's data.
|
|
- **CONTAINERS_RUNROOT**: the path to the volatile container's data.
|
|
|
|
## OPTIONS
|
|
|
|
#### **--help**, **-h**
|
|
|
|
Print usage statement
|
|
|
|
#### **--rootless-cni**
|
|
|
|
Join the rootless network namespace used for CNI networking. It can be used to
|
|
connect to a rootless container via IP address (CNI networking). This is otherwise
|
|
not possible from the host network namespace.
|
|
_Note: Using this option with more than one unshare session can have unexpected results._
|
|
|
|
## Exit Codes
|
|
|
|
The exit code from `podman unshare` gives information about why the container
|
|
failed to run or why it exited. When `podman unshare` commands exit with a non-zero code,
|
|
the exit codes follow the `chroot` standard, see below:
|
|
|
|
**125** The error is with podman **_itself_**
|
|
|
|
$ podman unshare --foo; echo $?
|
|
Error: unknown flag: --foo
|
|
125
|
|
|
|
**126** Executing a _contained command_ and the _command_ cannot be invoked
|
|
|
|
$ podman unshare /etc; echo $?
|
|
Error: fork/exec /etc: permission denied
|
|
126
|
|
|
|
**127** Executing a _contained command_ and the _command_ cannot be found
|
|
|
|
$ podman run busybox foo; echo $?
|
|
Error: fork/exec /usr/bin/bogus: no such file or directory
|
|
127
|
|
|
|
**Exit code** _contained command_ exit code
|
|
|
|
$ podman run busybox /bin/sh -c 'exit 3'; echo $?
|
|
3
|
|
|
|
## EXAMPLE
|
|
|
|
```
|
|
$ podman unshare id
|
|
uid=0(root) gid=0(root) groups=0(root),65534(nobody)
|
|
|
|
$ podman unshare cat /proc/self/uid_map /proc/self/gid_map
|
|
0 1000 1
|
|
1 10000 65536
|
|
0 1000 1
|
|
1 10000 65536
|
|
|
|
$ podman unshare --rootless-cni ip addr
|
|
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
|
|
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
|
|
inet 127.0.0.1/8 scope host lo
|
|
valid_lft forever preferred_lft forever
|
|
inet6 ::1/128 scope host
|
|
valid_lft forever preferred_lft forever
|
|
2: tap0: <BROADCAST,UP,LOWER_UP> mtu 65520 qdisc fq_codel state UNKNOWN group default qlen 1000
|
|
link/ether 36:0e:4a:c7:45:7e brd ff:ff:ff:ff:ff:ff
|
|
inet 10.0.2.100/24 brd 10.0.2.255 scope global tap0
|
|
valid_lft forever preferred_lft forever
|
|
inet6 fe80::340e:4aff:fec7:457e/64 scope link
|
|
valid_lft forever preferred_lft forever
|
|
3: cni-podman2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
|
|
link/ether 5e:3a:71:d2:b4:3a brd ff:ff:ff:ff:ff:ff
|
|
inet 10.89.1.1/24 brd 10.89.1.255 scope global cni-podman2
|
|
valid_lft forever preferred_lft forever
|
|
inet6 fe80::5c3a:71ff:fed2:b43a/64 scope link
|
|
valid_lft forever preferred_lft forever
|
|
4: vethd4ba3a2f@if3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master cni-podman2 state UP group default
|
|
link/ether 8a:c9:56:32:17:0c brd ff:ff:ff:ff:ff:ff link-netnsid 0
|
|
inet6 fe80::88c9:56ff:fe32:170c/64 scope link
|
|
valid_lft forever preferred_lft forever
|
|
```
|
|
|
|
|
|
## SEE ALSO
|
|
podman(1), podman-mount(1), namespaces(7), newuidmap(1), newgidmap(1), user\_namespaces(7)
|