Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Unblocks #2013.
Unblocks #2015.
Closes #1766.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Unblocks #2013.
Unblocks #2015.
Closes #1766.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Unblocks #2013.
Unblocks #2015.
Closes #1766.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

This can be used by scripts to detect what version of the hooks are used.

Unblocks #2013.
Unblocks #2015.
Closes #1766.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Unblocks #2013.
Unblocks #2015.
Closes #1766.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

start: fix cgroup namespace preservation

coverity: bugfixes

lxccontainer: only attach netns on netdev detach

tools: block using lxc-execute without config file

conf: avoid spawning unnecessary subshells

start: do not unconditionally dup std{in,out,err}

confile: add lxc.proc.* to set proc filesystem 

Signed-off-by: Yifeng Tan <tanyifeng1@huawei.com>

Prior to this patch we raced with a very short-lived init process. Essentially,
the init process could exit before we had time to record the cgroup namespace
causing the container to abort and report ABORTING to the caller when it
actually started just fine. Let's not do this.

(This uses syscall(SYS_getpid) in the the child to retrieve the pid just in case
we're on an older glibc version and we end up in the namespace sharing branch
of the actual lxc_clone() call.)

Additionally this fixes the shortlived tests. They were faulty so far and
should have actually failed because of the cgroup namespace recording race but
the ret variable used to return from the function was not correctly
initialized. This fixes it.
Furthermore, the shortlived tests used the c->error_num variable to determine
success or failure but this is actually not correct when the container is
started daemonized.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

The error_num value doesn't tell us anything since the container hasn't exited.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Starting with commit

    commit c5b93afb
    Author: Li Feng <lifeng68@huawei.com>
    Date:   Mon Jul 10 17:19:52 2017 +0800

        start: dup std{in,out,err} to pty slave

        In the case the container has a console with a valid slave pty file descriptor
        we duplicate std{in,out,err} to the slave file descriptor so console logging
        works correctly. When the container does not have a valid slave pty file
        descriptor for its console and is started daemonized we should dup to
        /dev/null.

        Closes #1646.
Signed-off-by: Li Feng <lifeng68@huawei.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

we made std{err,in,out} a duplicate of the slave file descriptor of the console
if it existed. This meant we also duplicated all of them when we executed
application containers in the foreground even if some std{err,in,out} file
descriptor did not refer to a {p,t}ty. This blocked use cases such as:

    echo foo | lxc-execute -n -- cat

which are very valid and common with application containers but less common
with system containers where we don't have to care about this. So my suggestion
is to unconditionally duplicate std{err,in,out} to the console file descriptor
if we are either running daemonized - this ensures that daemonized application
containers with a single bash shell keep on working - or when we are not
running an application container. In other cases we only duplicate those file
descriptors that actually refer to a {p,t}ty. This logic is similar to what we
do for lxc-attach already.

Refers to #1690.
Closes #2028.
Reported-by: Felix Abecassis <fabecassis@nvidia.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

remove logically dead code
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

free allocated memory
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

check return value of snprintf()
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

remove logically dead code
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

free allocated memory
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

initialize handler
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

remove logically dead code
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

free allocated memory
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

do not pass NULL pointer to chdir()
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

do not unmap prematurely
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

check snprintf() return value
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Detaching network namespaces as an unprivileged user is currently not possible
and attaching to the user namespace will mean we are not allowed to move the
network device into an ancestor network namespace.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

- check for memory allocation failure
- free allocated memory
- cleanup function
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

overlay: fix out-of-bounds copy

Signed-off-by: Jonathan Calmels <jcalmels@nvidia.com>

Moving away from internal symbols we can't do hacks like we currently do in
lxc-start and call internal functions like lxc_conf_init(). This is unsafe
anyway. Instead, we should simply error out if the user didn't give us a
configuration file to use. lxc-start refuses to start in that case already.

Relates to discussion in https://github.com/lxc/go-lxc/pull/96#discussion_r155075560 .
Closes #2023.
Reported-by: Felix Abecassis <fabecassis@nvidia.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Signed-off-by: Jonathan Calmels <jcalmels@nvidia.com>

start: intelligently use clone() on ns sharing

This also ensures that the new more efficient clone() way of sharing namespaces
is tested.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>