We can't call log.Fatalf() and defer functions, as the former doesn't
call any defers. Let's just move the code to a new function and call
os.Exit() only in main, when all defer executed.
Now that all the code is one function, we only print twice to stderr. It
is simpler to just print to stderr instead of logging and having also
the timestamp we don't really want.
Signed-off-by: Rodrigo Campos <rodrigoca@microsoft.com>
Let's just rely on the lookup performed to find the sleep binary.
This didn't cause any issues as far as I know, I just saw this while
doing other cleanups.
Signed-off-by: Rodrigo Campos <rodrigoca@microsoft.com>
We don't really need to check if AT_RECURSIVE is possible here. We just
want to check if we can idmap the src, it doesn't matter other nested
mounts.
While we are there, allow relative paths too.
Signed-off-by: Rodrigo Campos <rodrigoca@microsoft.com>
This aligns v2 usage calculations more closely with v1.
Current node-level reporting for v1 vs v2 on the same
machine under similar load may differ by ~250-750Mi.
Also return usage as combined swap + memory usage, aligned
with v1 and non-root v2 cgroups.
`mem_cgroup_usage` in the kernel counts NR_FILE_PAGES
+ NR_ANON_MAPPED + `nr_swap_pages` (if swap enabled) [^0].
Using total - free results in higher "usage" numbers.
This is likely due to various types of reclaimable
memory technically counted as in use (e.g. inactive anon).
See also https://github.com/kubernetes/kubernetes/issues/118916 for more context
[^0]: https://github.com/torvalds/linux/blob/06c2afb862f9da8dc5efa4b6076a0e48c3fbaaa5/mm/memcontrol.c#L3673-L3680
Signed-off-by: Alexander Eldeib <alexeldeib@gmail.com>
This is what we should do, although in practice this probably won't be a
big issue as the parent also exits.
While we are there, instead of waiting for the child to finish, kill it
if we did everything we wanted to do.
Signed-off-by: Rodrigo Campos <rodrigoca@microsoft.com>
While testing this with old kernel versions and kernels that don't
support idmap mounts for some of the filesystems used by a container, I
realized we can throw a more clear errors.
Let's make it clear which syscall we are using, when it is not supported
and when if the fs doesn't support idmap mounts, which path it is.
Signed-off-by: Rodrigo Campos <rodrigoca@microsoft.com>
Since systemd v240 (commit 8e8b5d2e6d91180a), one can use
/dev/{char,block}-MAJOR syntax to specify that all MAJOR:*
devices are allowed.
Use it, if available, since it's more straightforward, plus
we can skip somewhat expensive parsing of /proc/devices.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Currently bind mounts of filesystems with nodev, nosuid, noexec,
noatime, relatime, strictatime, nodiratime options set fail in rootless
mode if the same options are not set for the bind mount.
For ro filesystems this was resolved by #2570 by remounting again
with ro set.
Follow the same approach for nodev, nosuid, noexec, noatime, relatime,
strictatime, nodiratime but allow to revert back to the old behaviour
via the new `--no-mount-fallback` command line option.
Add a testcase to verify that bind mounts of filesystems with nodev,
nosuid, noexec, noatime options set work in rootless mode.
Add a testcase that mounts a nodev, nosuid, noexec, noatime filesystem
with a ro flag.
Add two further testcases that ensure that the above testcases would
fail if the `--no-mount-fallback` command line option is set.
* contrib/completions/bash/runc:
Add `--no-mount-fallback` command line option for bash completion.
* create.go:
Add `--no-mount-fallback` command line option.
* restore.go:
Add `--no-mount-fallback` command line option.
* run.go:
Add `--no-mount-fallback` command line option.
* libcontainer/configs/config.go:
Add `NoMountFallback` field to the `Config` struct to store
the command line option value.
* libcontainer/specconv/spec_linux.go:
Add `NoMountFallback` field to the `CreateOpts` struct to store
the command line option value and store it in the libcontainer
config.
* utils_linux.go:
Store the command line option value in the `CreateOpts` struct.
* libcontainer/rootfs_linux.go:
In case that `--no-mount-fallback` is not set try to remount the
bind filesystem again with the options nodev, nosuid, noexec,
noatime, relatime, strictatime or nodiratime if they are set on
the source filesystem.
* tests/integration/mounts_sshfs.bats:
Add testcases and rework sshfs setup to allow specifying
different mount options depending on the test case.
Signed-off-by: Ruediger Pluem <ruediger.pluem@vodafone.com>
We cannot have both srcFD and idMapFD set at the same time.
So, we can simplify this struct to only have one field which is used a srcFD
most of the time and as idMapFD when we do an id map mount.
Signed-off-by: Francis Laniel <flaniel@linux.microsoft.com>
Previously to this commit, we used a string for srcFD as /proc/self/fd/NN.
This commit modified to this behavior, so srcFD is only an *int and the full path
is constructed in mountViaFDs() if srcFD is different than nil.
Signed-off-by: Francis Laniel <flaniel@linux.microsoft.com>
runc ps requires cgroup, but all the tests but one required root. Let's
fix this.
1. Add rootless cgroup requirement to setup() to avoid repetition.
2. Add set_cgroups_path to setup() for rootless containers because
there is no default cgroup path.
3. Modify output checks to use $output rather than $lines because in case
of rootless the first line of output contains the following warning:
> runc ps may fail if you don't have the full access to cgroups
4. While at it, move the common part of every test (creating the
container and making sure it's running) to setup().
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
This commit adds support for idmap mounts as specified in the runtime-spec.
We open the idmap source paths and call mount_setattr() in runc PARENT,
as we need privileges in the init userns for that, and then sends the
fds to the child process. For this fd passing we use the same mechanism
used in other parts of thecode, the _LIBCONTAINER_ env vars.
The mount is finished (unix.MoveMount) from go code, inside the userns,
so we reuse all the prepareBindMount() security checks and the remount
logic for some flags too.
This commit only supports idmap mounts when userns are used AND the mappings
are the same specified for the userns mapping. This limitation is to
simplify the initial implementation, as all our users so far only need
this, and we can avoid sending over netlink the mappings, creating a
userns with this custom mapping, etc. Future PRs will remove this
limitation.
Co-authored-by: Francis Laniel <flaniel@linux.microsoft.com>
Signed-off-by: Rodrigo Campos <rodrigoca@microsoft.com>
We will need to pass more slices of fds to these functions in future
patches. Let's add a struct that just contains them all, instead of
adding lot of parameters to these functions.
Signed-off-by: Rodrigo Campos <rodrigoca@microsoft.com>
We will add code that uses this function in future patches. So let's
just split it to a new function now and reuse it later.
Signed-off-by: Rodrigo Campos <rodrigoca@microsoft.com>
Let's move the code to send mount sources to a generic function. Future
patches will use it for idmap sources too.
Signed-off-by: Rodrigo Campos <rodrigoca@microsoft.com>
We add idmap.h with the needed includes and defines in case the system
headers don't have the definition for the idmap syscalls we need.
Future patches will use these helpers.
Co-authored-by: Francis Laniel <flaniel@linux.microsoft.com>
Signed-off-by: Rodrigo Campos <rodrigoca@microsoft.com>
We just added this helper for other parts of the code, let's switch this
function to use the helper too.
Signed-off-by: Rodrigo Campos <rodrigoca@microsoft.com>
Kir Kolyshkin