This fixes the following compilation error on 32bit ARM:
```
$ GOARCH=arm GOARCH=6 go build ./libcontainer/system/
libcontainer/system/linux.go:119:89: constant 4294967295 overflows int
```
Signed-off-by: Tibor Vass <tibor@docker.com>
When a subreaper is enabled, it might expect to reap a process and
retrieve its exit code. That's the reason why this patch is giving
the possibility to define the usage of a subreaper as a consumer of
libcontainer. Relying on this information, libcontainer will not
wait for signalled processes in case a subreaper has been set.
Fixes#1677
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
runc is not supported on FreeBSD, so remove all FreeBSD specific bits.
As suggested by @crosbymichael in #1653
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
There are essentially two possible implementations for Setuid/Setgid on
Linux, either using SYS_SETUID32/SYS_SETGID32 or SYS_SETUID/SYS_SETGID,
depending on the architecture (see golang/go#1435 for why Setuid/Setgid
aren currently implemented for Linux neither in syscall nor in
golang.org/x/sys/unix).
Reduce duplication by merging the currently implemented variants and
adjusting the build tags accordingly.
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Use IoctlGetInt and IoctlGetTermios/IoctlSetTermios instead of manually
reimplementing them.
Because of unlockpt, the ioctl wrapper is still needed as it needs to
pass a pointer to a value, which is not supported by any ioctl function
in x/sys/unix yet.
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Use unix.Prctl() instead of manually reimplementing it using
unix.RawSyscall. Also use unix.SECCOMP_MODE_FILTER instead of locally
defining it.
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
And Stat_t.PID and Stat_t.Name while we're at it. Then use the new
.State property in runType to distinguish between running and
zombie/dead processes, since kill(2) does not [1]. With this change
we no longer claim Running status for zombie/dead processes.
I've also removed the kill(2) call from runType. It was originally
added in 13841ef3 (new-api: return the Running state only if the init
process is alive, 2014-12-23), but we've been accessing
/proc/[pid]/stat since 14e95b2a (Make state detection precise,
2016-07-05, #930), and with the /stat access the kill(2) check is
redundant.
I also don't see much point to the previously-separate
doesInitProcessExist, so I've inlined that logic in runType.
It would be nice to distinguish between "/proc/[pid]/stat doesn't
exist" and errors parsing its contents, but I've skipped that for the
moment.
The Running -> Stopped change in checkpoint_test.go is because the
post-checkpoint process is a zombie, and with this commit zombie
processes are Stopped (and no longer Running).
[1]: https://github.com/opencontainers/runc/pull/1483#issuecomment-307527789
Signed-off-by: W. Trevor King <wking@tremily.us>
Use the symlink xattr syscall wrappers Lgetxattr, Llistxattr and
Lsetxattr from x/sys/unix (introduced in
golang/sys@b90f89a1e7) instead of
providing own wrappers. Leave the functionality of system.Lgetxattr
intact with respect to the retry with a larger buffer, but switch it to
use unix.Lgetxattr.
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Since syscall is outdated and broken for some architectures,
use x/sys/unix instead.
There are still some dependencies on the syscall package that will
remain in syscall for the forseeable future:
Errno
Signal
SysProcAttr
Additionally:
- os still uses syscall, so it needs to be kept for anything
returning *os.ProcessState, such as process.Wait.
Signed-off-by: Christy Perez <christy@linux.vnet.ibm.com>
The original SETUID takes a 16 bit UID. Linux 2.4 introduced a new
syscall, SETUID32, with support for 32 bit UIDs. The setgid wrapper
already uses SETGID32.
Signed-off-by: Carl Henrik Lunde <chlunde@ifi.uio.no>
Revert: #935Fixes: #946
I can reproduce #946 on some machines, the problem is on
some machines, it could be very fast that modify time
of `memory.kmem.limit_in_bytes` could be the same as
before it's modified.
And now we'll call `SetKernelMemory` twice on container
creation which cause the second time failure.
Revert this before we find a better solution.
Signed-off-by: Qiang Huang <h.huangqiang@huawei.com>
No substantial code change.
Note that some style errors reported by `golint` are not fixed due to possible compatibility issues.
Signed-off-by: Akihiro Suda <suda.kyoto@gmail.com>
Fixes#680
This changes setupRlimit to use the Prlimit syscall (rather than
Setrlimit) and moves the call to the parent process. This is necessary
because Setrlimit would affect the libcontainer consumer if called in
the parent, and would fail if called from the child if the
child process is in a user namespace and the requested rlimit is higher
than that in the parent.
Signed-off-by: Julian Friedman <julz.friedman@uk.ibm.com>
We need to make sure the container is destroyed before closing the stdio
for the container. This becomes a big issues when running in the host's
pid namespace because the other processes could have inherited the stdio
of the initial process. The call to close will just block as they still
have the io open.
Calling destroy before closing io, especially in the host pid namespace
will cause all additional processes to be killed in the container's
cgroup. This will allow the io to be closed successfuly.
This change makes sure the order for destroy and close is correct as
well as ensuring that if any errors encoutered during start or exec will
be handled by terminating the process and destroying the container. We
cannot use defers here because we need to enforce the correct ordering
on destroy.
This also sets the subreaper setting for runc so that when running in
pid host, runc can wait on the addiontal processes launched by the
container, useful on destroy, but also good for reaping the additional
processes that were launched.
Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
When we launch a container in a new user namespace, we cannot create
devices, so we bind mount the host's devices into place instead.
If we are running in a user namespace (i.e. nested in a container),
then we need to do the same thing. Add a function to detect that
and check for it before doing mknod.
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
---
Changelog - add a comment clarifying what's going on with the
uidmap file.