Antonio Terceiro [Sat, 28 Oct 2017 11:20:35 +0000 (09:20 -0200)]
lxc-debian: don't hardcode valid releases
This avoids the dance of updating the list of valid releases every time
Debian makes a new release.
It also fixes the following bug: even though lxc-debian will default to
creating containers of the latest stable by querying the archive, it
won't allow you to explicitly request `stable` because the current list
of valid releases don't include it.
Last, but not least, avoid hitting the mirror in the case the desired
release is one of the ones we know will always be there, i.e. stable,
testing, sid, and unstable.
Signed-off-by: Antonio Terceiro <terceiro@debian.org>
Antonio Terceiro [Thu, 26 Oct 2017 22:42:49 +0000 (20:42 -0200)]
lxc-debian: allow creating `testing` and `unstable`
Being able to create `testing` containers, regardless of what's the name
of the next stable, is useful in several contexts, included but not
limited to testing purposes. i.e. one won't need to explicitly switch to
`bullseye` once `buster` is released to be able to continue tracking
`testing`. While we are at it, let's also enable `unstable`, which is
exactly the same as `sid`, but there is no reason for not being able to.
Signed-off-by: Antonio Terceiro <terceiro@debian.org>
To match names beginning with the letters "f" or "b" one can use
the regular expression "[fb].*" or "(f|b).*", but not "[f|b].*",
which would match strings beginning with "f", "|", or "b".
Signed-off-by: Christian von Roques <roques@z12.ch>
Long Wang [Sat, 8 Jul 2017 02:29:57 +0000 (10:29 +0800)]
af_unix: remove unlink operation
It is not necessary to unlink the abstract socket pathname when
we have finished using the socket. The abstract name is automatically
removed when the socket is closed.
This patch allows users to start containers in AppArmor namespaces.
Users can define their own profiles for their containers, but
lxc-start must be allowed to change to a namespace.
A container configuration file can wrap a container in an AppArmor
profile using lxc.aa_profile.
A process in an AppArmor namespace is restricted to view
or manage only the profiles belonging to this namespace, as if no
other profiles existed. A namespace can be created as follow:
sudo mkdir /sys/kernel/security/apparmor/policy/namespaces/$NAMESPACE
AppArmor can stack profiles so that the contained process is bound
by the intersection of all profiles of the stack. This is achieved
using the '//&' operator as follow:
In this case, even the guest process appears unconfined in the
namespace, it is still confined by $PROFILE.
A guest allowed to access "/sys/kernel/security/apparmor/** rwklix,"
will be able to manage its own profile set, while still being
enclosed in the topmost profile $PROFILE:
Different guests can be assigned the same namespace or different
namespaces. In the first case, they will share their profiles.
In the second case, they will have distinct sets of profiles.
use cppcheck tools `cppcheck --enable=warning .` on lxc source directory.
This patch fix the following warnning
```
[src/lxc/cgroups/cgfs.c:794]: (warning) %ld in format string (no. 3) requires 'long' but the argument type is 'unsigned long'.
[src/lxc/confile.c:4441]: (warning) %d in format string (no. 2) requires 'int' but the argument type is 'unsigned int'.
[src/lxc/confile.c:4502]: (warning) %d in format string (no. 2) requires 'int' but the argument type is 'unsigned int'.
[src/lxc/confile_legacy.c:921]: (warning) %d in format string (no. 2) requires 'int' but the argument type is 'unsigned int'.
[src/lxc/confile_legacy.c:938]: (warning) %d in format string (no. 2) requires 'int' but the argument type is 'unsigned int'.
[src/lxc/lxclock.c:63]: (warning) %zd in format string (no. 1) requires 'ssize_t' but the argument type is 'size_t {aka unsigned long}'.
[src/lxc/tools/lxc_info.c:118]: (warning) %u in format string (no. 1) requires 'unsigned int' but the argument type is 'signed int'.
[src/lxc/tools/lxc_info.c:118]: (warning) %u in format string (no. 2) requires 'unsigned int' but the argument type is 'signed int'.
[src/lxc/tools/lxc_info.c:123]: (warning) %u in format string (no. 1) requires 'unsigned int' but the argument type is 'signed int'.
[src/lxc/tools/lxc_info.c:127]: (warning) %u in format string (no. 1) requires 'unsigned int' but the argument type is 'signed int'.
[src/lxc/tools/lxc_info.c:130]: (warning) %u in format string (no. 1) requires 'unsigned int' but the argument type is 'signed int'.
[src/lxc/tools/lxc_top.c:212]: (warning) %u in format string (no. 1) requires 'unsigned int' but the argument type is 'signed int'.
[src/lxc/tools/lxc_top.c:212]: (warning) %u in format string (no. 2) requires 'unsigned int' but the argument type is 'signed int'.
[src/lxc/tools/lxc_top.c:217]: (warning) %u in format string (no. 1) requires 'unsigned int' but the argument type is 'signed int'.
[src/lxc/tools/lxc_top.c:221]: (warning) %u in format string (no. 1) requires 'unsigned int' but the argument type is 'signed int'.
[src/lxc/tools/lxc_top.c:224]: (warning) %u in format string (no. 1) requires 'unsigned int' but the argument type is 'signed int'.
```
In case the lxc command socket is hashed and the socket was created for a
different path than the one we're currently querying
lxc_cmd_get_{lxcpath,name}() can return NULL. The command socket path is hashed
when len(lxcpath) > sizeof(sun_path) - 2.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
These functions define pointer to their key shifted by a
number and guard access to it later via another variable.
Let's make this more explicit (and additionally have the
pointer be NULL in the case where it is not supposed to be
used).
Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>
Thomas Jarosch [Thu, 2 Feb 2017 11:48:35 +0000 (12:48 +0100)]
lxc_setup_tios(): Ignore SIGTTOU and SIGTTIN signals
Prevent an endless loop while executing lxc-attach in the background:
The kernel might fire SIGTTOU while an ioctl() in tcsetattr()
is executed. When the ioctl() is resumed and retries,
the signal handler interrupts it again.
We can't configure the TTY to stop sending
the signals in the first place since that
is a modification/write to the TTY already.
Still we clear the TOSTOP flag to prevent further signals.
Command to reproduce the hang:
----------------------------
cat > lxc_hang.sh << EOF
/usr/bin/timeout 5s /usr/bin/lxc-attach -n SOMECONTAINER -- /bin/true
EOF
sh lxc_hang.sh # hangs
----------------------------
Signed-off-by: Thomas Jarosch <thomas.jarosch@intra2net.com>
Previous versions of lxc-attach simply attached to the specified namespaces of
a container and ran a shell or the specified command without first allocating a
pseudo terminal. This made them vulnerable to input faking via a TIOCSTI ioctl
call after switching between userspace execution contexts with different
privilege levels. Newer versions of lxc-attach will try to allocate a pseudo
terminal master/slave pair on the host and attach any standard file descriptors
which refer to a terminal to the slave side of the pseudo terminal before
executing a shell or command. Note, that if none of the standard file
descriptors refer to a terminal lxc-attach will not try to allocate a pseudo
terminal. Instead it will simply attach to the containers namespaces and run a
shell or the specified command.
(This is a backport of a series of patches fixing CVE-2016-10124.)
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
- Make escape sequence to exit tty optional since we want to reuse
lxc_console_cb_tty_stdin() in lxc_attach.c.
- Export the following functions since they can be reused in other modules:
- lxc_console_cb_tty_stdin()
- lxc_console_cb_tty_master()
- lxc_setup_tios(int fd, struct termios *oldtios);
- lxc_console_winsz(int srcfd, int dstfd);
- lxc_console_cb_sigwinch_fd(int fd, uint32_t events, void *cbdata, struct lxc_epoll_descr *descr);
- lxc_tty_state *lxc_console_sigwinch_init(int srcfd, int dstfd);
- lxc_console_sigwinch_fini(struct lxc_tty_state *ts);
- rewrite lxc_console_set_stdfds()
- Make lxc_console_set_stdfds useable by other callers that do not have
access to lxc_handler.
- Use ssh settings for ptys.
- Remove all asserts from console.{c,h}.
- Adapt start.c to changes.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>