if the pause process cannot be joined, remove the pause.pid while
keeping a lock on it, and try to recreate it.
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
If we don't do this, we print WARN level messages that we should
not be printing by default.
Up one WARN message to ERROR so it still shows up by default.
Fixes: #4115Fixes: #4012
Signed-off-by: Matthew Heon <matthew.heon@pm.me>
detect if the current user namespace doesn't match the configuration
in the /etc/subuid and /etc/subgid files.
If there is a mismatch, raise a warning and suggest the user to
recreate the user namespace with "system migrate", that also restarts
the containers.
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
unfortunately rootless won't work without cgo, as most of the
implementation is in C, but at least allow to build libpod.
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
do not attempt to join the rootless namespace if it is running already
with euid == 0.
Closes: https://github.com/containers/libpod/issues/3463
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
Currently pause process blocks all signals which may cause its
termination, including SIGTERM. This behavior hangs init(1) during
system shutdown, until pause process gets SIGKILLed after some grace
period. To avoid this hanging, SIGTERM is excluded from list of blocked
signals.
Fixes#3440
Signed-off-by: Danila Kiver <danila.kiver@mail.ru>
at least on Fedora 30 it creates the /run/user/UID directory for the
user logged in via ssh.
This needs to be done very early so that every other check when we
create the default configuration file will point to the correct
location.
Closes: https://github.com/containers/libpod/issues/3410
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
To avoid unnecessary warnings and errors in the future I'd like to
propose building all cgo related sources with `-Wall -Werror`. This
commit fixes some warnings which came up in `shm_lock.c`, too.
Signed-off-by: Sascha Grunert <sgrunert@suse.com>
The second argument of `execlp` should be of type `char *`, so we need
to add an additional argument there.
Signed-off-by: Sascha Grunert <sgrunert@suse.com>
on old kernels the ioctl NS_GET_PARENT is not available.
Handle the error code and immediately return the same fd. It should
be fine now that we use the namespace resolution using the conmon pid,
so the namespace parent resolution is just a safety measure.
Closes: https://github.com/containers/libpod/issues/2968
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
we are allowed to use only signal safe functions between a fork of a
multithreaded application and the next execve. Since setenv(3) is not
signal safe, block signals. We are already doing it for creating a
new namespace.
This is mostly a cleanup since reexec_in_user_namespace_wait is used
only only to join existing namespaces when we have not a pause.pid
file.
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
after we read from the pause PID file, NUL terminate the buffer to
avoid reading garbage from the stack.
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
move the logic for joining existing namespaces down to the rootless
package. In main_local we still retrieve the list of conmon pid files
and use it from the rootless package.
In addition, create a temporary user namespace for reading these
files, as the unprivileged user might not have enough privileges for
reading the conmon pid file, for example when running with a different
uidmap and root in the container is different than the rootless user.
Closes: https://github.com/containers/libpod/issues/3187
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
add a shortcut for joining immediately the namespace so we don't need
to re-exec Podman.
With the pause process simplificaton, we can now attempt to join the
namespaces as soon as Podman starts (and before the Go runtime kicks
in), so that we don't need to re-exec and use just one process.
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
use a pause process to keep the user and mount namespace alive.
The pause process is created immediately on reload, and all successive
Podman processes will refer to it for joining the user&mount
namespace.
This solves all the race conditions we had on joining the correct
namespaces using the conmon processes.
As a fallback if the join fails for any reason (e.g. the pause process
was killed), then we try to join the running containers as we were
doing before.
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
we were previously closing as many FDs as they were open when we first
started Podman in the range (3-MAX-FD). This would cause issues if
there were empty intervals, as these FDs are later on used by the
Golang runtime. Store exactly what FDs were first open in a fd_set,
so that we can close exactly the FDs that were open at startup.
Closes: https://github.com/containers/libpod/issues/2964
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
we were previously proxying all the signals, but doing that for
SIGTSTP prevented the main process to be stopped by the tty.
Closes: https://github.com/containers/libpod/issues/2775
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
simplify the rootless implementation to use a single user namespace
for all the running containers.
This makes the rootless implementation behave more like root Podman,
where each container is created in the host environment.
There are multiple advantages to it: 1) much simpler implementation as
there is only one namespace to join. 2) we can join namespaces owned
by different containers. 3) commands like ps won't be limited to what
container they can access as previously we either had access to the
storage from a new namespace or access to /proc when running from the
host. 4) rootless varlink works. 5) there are only two ways to enter
in a namespace, either by creating a new one if no containers are
running or joining the existing one from any container.
Containers created by older Podman versions must be restarted.
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
in the few places where we care about skipping the storage
initialization, we can simply use the process effective UID, instead
of relying on a global boolean flag.
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
from _LIBPOD to _CONTAINERS. The same change was done in buildah
unshare.
This is necessary for podman to detect we are running in a rootless
environment and work properly from a "buildah unshare" session.
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
