Currently, all scripts, specified as "lxc.network.script.up", inherit
lxc-execute's signal mask.
This, for example, includes blocked SIGALRM signal which, in turn, makes
alarm(2), sleep(3) and setitimer(2) functions silently unusable in all programs,
invoked in turn by the "lxc.network.script.up".
To fix this, run_buffer() should restore default signal mask prior to
executing "lxc.network.script.up".
A naive implementation would temprorary unblock all signals just before
calling popen() and block them back immediately after it.
But that would result in an immediate delivery of all pending signals just
after their unblocking.
Thus, we should restore default signal mask exactly in child (after fork())
just before calling exec().
To achieve this, a home-brewed popen() alternative is needed.
The added lxc_popen() and lxc_pclose() are mostly taken from glibc with
several simplifications (as we currently need only "re" mode).
The implementation uses Linux-specific pipe2() system-call,
which is only available since Linux 2.6.27 and supported by glibc since
version 2.9 (according to pipe(2) man-page), but this shouldn't be a
problem as lxc requires a fairly recent kernel too.
lxc_popen()/lxc_pclose() are meant to be direct replacements for their
stdio counterparts, so they perform no process_lock() locking
themselves. (as fopen_cloexec() does)
All existing users of popen()/pclose() are converted to the new
lxc_popen()/lxc_pclose().
(mazo: don't clear close-on-exec flag for parent's end;
place the new functions in utils.c;
convert bdev.c to use the new functions;
coding style fixes;
comments fixes;
commit message tweaks)
Signed-off-by: Ivan Bolsunov <bolsunov@telum.ru>
Signed-off-by: Andrey Mazo <mazo@telum.ru>
In general proc gets mounted ahead of time, so init shouldn't
have to do it. Without this patch, you cannot
lxc-execute -n x1 -s lxc.cap.drop=sys_admin /bin/bash
(See https://bugs.launchpad.net/ubuntu/+source/lxc/+bug/1253669 for
a bug about this)
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>
This is necessary to have the rights to remove files owned by our subuids.
Also update lxc_rmdir_onedev to return 0 on success, -1 on failure.
Callers were not consistent in using it correctly, and this is more
in keeping with the rest of our code.
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>
Conflict occurs between following lines
[...]
269 if (values[i])
270 return values[i];
[...]
and
[...]
309 /* could not find value, use default */
310 values[i] = (*ptr)[1];
[...]
fix it using a specific lock dedicated to that problem as Serge suggested.
Also introduce a new autoconf parameter (--enable-mutex-debugging) to convert mutexes to error reporting type and to provide a stacktrace when locking fails.
Signed-off-by: S.Çağlar Onur <caglar@10ur.org>
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
In a few places we checked for LONG_MIN or LONG_MAX as indication
that strtoul failed. That's not reliable. As suggested in the
manpage, switch to checking errno value.
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Will fallback to no thinpool if not present or if thin pool provided on the command line does not exist.
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Section 7.1.2 of the gnutls info manual states that it must be
initialized with a call to gnutls_global_init before use. This
fixes the syslog warning I was seeing:
lxc-create: Libgcrypt warning: missing initialization -
please fix the application
Signed-off-by: Dwight Engen <dwight.engen@oracle.com>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>
get_ips accepts an interface name as a parameter but there was no
way to get the interfaces names from the container. This patch
introduces a new get_interfaces call to the API so that users
can obtain the name of the interfaces.
Support for python bindings also introduced as a part of this version.
Signed-off-by: S.Çağlar Onur <caglar@10ur.org>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>
pthread_mutex_lock() will only return an error if it was set to
PTHREAD_MUTEX_ERRORCHECK and we are recursively calling it (and
would otherwise have deadlocked). If that's the case then log a
message for future debugging and exit. Trying to "recover" is
nonsense at that point.
process_lock() was held over too long a time in lxcapi_start()
in the daemonize case. (note the non-daemonized case still needs a
check to enforce that it must NOT be called while threaded). Add
process_lock() at least across all open/close/socket() calls.
Anything done after a fork() doesn't need the locks as it is no
longer threaded - so some open/close/dups()s are not locked for
that reason. However, some common functions are called from both
threaded and non-threaded contexts. So after doing a fork(), do
a possibly-extraneous process_unlock() to make sure that, if we
were forked while pthread mutex was held, we aren't deadlocked by
nobody.
Tested that lp:~serge-hallyn/+junk/lxc-test still works with this
patch.
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Tested-by: S.Çağlar Onur <caglar@10ur.org>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>
Moving these files should allow $lxcpath to be a read-only fs.
Signed-off-by: Dwight Engen <dwight.engen@oracle.com>
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
This patch rewrites most of the cgroup logic. It creates a set of data
structures to store the kernel state of the cgroup hierarchies and
their mountpoints.
Mainly, everything is now grouped with respect to the hierarchies of
the system. Multiple controllers may be mounted together or separately
to different hierarchies, the data structures reflect this.
Each hierarchy may have multiple mount points (that were created
previously using the bind mount method) and each of these mount points
may point to a different prefix inside the cgroup tree. The current
code does not make any assumptions regarding the mount points, it just
parses /proc/self/mountinfo to acquire the relevant information.
The only requirement is that the current cgroup of either init (if
cgroup.pattern starts with '/' and the tools are executed as root) or
the current process (otherwise) are accessible. The root cgroup need
not be accessible.
The configuration option cgroup.pattern is introduced. For
root-executed containers, it specifies which format the cgroups should
be in. Example values may include '/lxc/%n', 'lxc/%n', '%n' or
'/machine/%n.lxc'. Any occurrence of '%n' is replaced with the name of
the container (and if clashes occur in any hierarchy, -1, -2, etc. are
appended globally). If the pattern starts with /, new containers'
cgroups will be located relative to init's cgroup; if it doesn't, they
will be located relative to the current process's cgroup.
Some changes to the cgroup.h API have been done to make it more
consistent, both with respect to naming and with respect to the
parameters. This causes some changes in other parts of the code that
are included in the patch.
There has been some testing of this functionality, but there are
probably still quite a few bugs in there, especially for people with
different configurations.
Signed-off-by: Christian Seiler <christian@iwakd.de>
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Adds a few useful string and array manipulation functions to utils.[ch]
Signed-off-by: Christian Seiler <christian@iwakd.de>
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Newer glibc versions (that we can't require) allow for an additional
letter 'e' in the fopen mode that will cause the file to be opened with
the O_CLOEXEC flag, so that it will be closed if the program exec()s
away. This is important because if liblxc is used in a multithreaded
program, another thread might want to run a program. This options
prevents the leakage of file descriptors from LXC. This patch adds an
emulation for that that uses the open(2) syscall and fdopen(3). At some
later point in time, it may be dropped against fopen(..., "...e").
This commit also converts all fopen() calls in utils.c (where the
function is added) to fopen_cloexec(). Subsequently, other calls to
fopen() and open() should also be adapted.
Signed-off-by: Christian Seiler <christian@iwakd.de>
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Instead of duplicating the code for parsing the global config file for
each option, write one main function, lxc_global_config_value, that
does the parsing for an arbitrary option name and just call that
function from the existing ones.
Signed-off-by: Christian Seiler <christian@iwakd.de>
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
strdup and strndup still don't exist on bionic, so we need to do the
alloc() call ourselves or free the memory by hand.
Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>
Acked-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Define a sha1sum_file() function in utils.c. Use that in lxcapi_create
to write out the sha1sum of the template being used. If libgnutls is
not found, then the template sha1sum simply won't be printed into the
container config.
This patch also trivially fixes some cases where SYSERROR is used after
a fclose (masking errno) and missing consts in mkdir_p.
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
The 'lxc-init' (a lightweight init process used by lxc-execute in place
of upstart etc) tries to mount /dev/mqueue during startup. If that fails
(for instance due to missing support for mqueue in kernel) then it
aborts execution and returns -1. This is unreasonable as very few
applications actually need /dev/mqueue.
This similar to what we do with /dev/shm.
Signed-off-by: Natanael Copa <ncopa@alpinelinux.org>
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
This requires implementing bdev->ops->destroy() for each of the backing
store types. Then implementing lxcapi_clone(), writing lxc_destroy.c
using the api, and removing the lxc-destroy.in script.
(this also has a few other cleanups, like marking some functions
static)
Changelog:
fold into destroy: fix zfs destroy
destroy: use correct program name in help
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
/etc/lxc/lxc.conf can contain
zfsroot = custom1
lvm_vg = vg0
(Otherwise the defaults are 'lxc' for lvm_vg, and 'lxc' for zfsroot)
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
1. commonize waitpid users to use a single helper. We frequently want
to run something in a clean namespace, or fork off a script. This
lets us keep the function doing fork:(1)exec(2)waitpid simpler.
2. start a blockdev backend implementation. This will be used for
mounting, copying, and snapshotting container filesystems.
3. implement btrfs, lvm, directory, and overlayfs backends.
4. For overlayfs, support a new lxc.rootfs format of
'bdevtype:<extra>'. This means you can now use overlayfs-based
containers without using lxc-start-ephemeral, by using
lxc.rootfs = overlayfs:/readonly-dir:writeable-dir
5. add a set of simple clone testcases
6. Write a new lxc_clone.c based on api clone.
Still to do (there's more, but off top of my head):
1. support zfs, aufs
2. have clone handle other mount entries (right now it only clones
the rootfs)
3. python, lua, and go bindings (not me :)
4. lxc-destroy: if lvm backing store, check for snapshots of it.
(what about directories which have overlayfs clones?)
Changes since v2:
Initialize random generator when picking new macaddr (reported
by caglar@10ur.org)
Fix wrong use of bitmask flags
On copy-clone of btrfs, create a subvolume
lxc_clone.c: respect the command line usage of the old script
lxc-clone(1): update documentation
Refuse to try changing backing stores expect to overlayfs, as
it is not implemented (yet) anyway.
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Conflicts:
src/lxc/utils.h
Reimplement mkdir_p() such that it:
...handles relativ paths correctly. (currently it crashes)
...does not rely on dirname().
...is not recursive.
...is shorter. ;-)
Signed-off-by: Richard Weinberger <richard@nod.at>
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com>
This reverts commit 8de4140644.
This commit was preventing container startup on my machine, making them
all fail with various "No such file or directory" errors.
Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>
Reimplement mkdir_p() such that it:
...handles relativ paths correctly. (currently it crashes)
...does not rely on dirname().
...is not recursive.
...is shorter. ;-)
Signed-off-by: Richard Weinberger <richard@nod.at>
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com>
As Richard reported, dirname('//') returns //. But mkdir_p only stops
when called with '/', resulting in infinite recursion when given a
pathname '//foo/bar'.
Reported-by: richard -rw- weinberger <richard.weinberger@gmail.com>
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Commit e3642c43 added lxc_copy_file for use in 64e1ae63. The use of it
was removed in commit 1bc60a65. Removing it reduces dead code and the
footprint of liblxc.
Signed-off-by: Dwight Engen <dwight.engen@oracle.com>
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
For the lxc-* C binaries, introduce a -P|--lxcpath command line option
to override the system default.
With this, I can
lxc-create -t ubuntu -n r1
lxc-create -t ubuntu -n r1 -P /home/ubuntu/lxcbase
lxc-start -n r1 -d
lxc-start -n r1 -d -P /home/ubuntu/lxcbase
lxc-console -n r1 -d -P /home/ubuntu/lxcbase
lxc-stop -n r1
all working with the right containers (module cgroup stuff).
To do:
* lxc monitor needs to be made to handle cgroups.
This is another very invasive one. I started doing this as
a part of this set, but that gets hairy, so I'm sending this
separately. Note that lxc-wait and lxc-monitor don't work
without this, and there may be niggles in what I said works
above - since start.c is doing lxc_monitor_send_state etc
to the shared abstract unix domain socket.
* Need to handle the cgroup conflicts.
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>
Here is a patch to introduce a configurable system-wide
lxcpath. It seems to work with lxc-create, lxc-start,
and basic python3 lxc usage through the api.
For shell functions, a new /usr/share/lxc/lxc.functions is
introduced which sets some of the basic global variables,
including evaluating the right place for lxc_path.
I have not converted any of the other python code, as I was
not sure where we should keep the common functions (i.e.
for now just default_lxc_path()).
configure.ac: add an option for setting the global config file name.
utils: add a default_lxc_path() function
Use default_lxc_path in .c files
define get_lxc_path() and set_lxc_path() in C api
use get_lxc_path() in lua api
create sh helper for getting default path from config file
fix up scripts to use lxc.functions
Changelog:
feb6:
fix lxc_path in lxc.functions
utils.c: as Dwight pointed out, don't close a NULL fin.
utils.c: fix the parsing of lxcpath line
lxc-start: print which rcfile we are using
commands.c: As Dwight alluded to, the sockname handling was just
ridiculous. Clean that up.
use Dwight's recommendation for lxc.functions path: $datadir/lxc
make lxccontainer->get_config_path() return const char *
Per Dwight's suggestion, much nicer than returning strdup.
feb6 (v2):
lxccontainer: set c->config_path before using it.
convert legacy lxc-ls
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>
ushort appears to be a glibc specific type which doesn't exist in
bionic, this commit simply replace all occurences by the equivalent
unsigned short type.
Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com>
