This includes quite a few cleanups and improvements to the way we do
synchronisation. The core behaviour is unchanged, but switching to
embedding json.RawMessage into the synchronisation structure will allow
us to do more complicated synchronisation operations in future patches.
The file descriptor passing through the synchronisation system feature
will be used as part of the idmapped-mount and bind-mount-source
features when switching that code to use the new mount API outside of
nsexec.c.
Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Since Go 1.19, godoc recognizes lists, code blocks, headings etc. It
also reformats the sources making it more apparent that these features
are used.
Fix a few places where it misinterpreted the formatting (such as
indented vs unindented), and format the result using the gofumpt
from HEAD, which already incorporates gofmt 1.19 changes.
Some more fixes (and enhancements) might be required.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
This commit implements support for the SCMP_ACT_NOTIFY action. It
requires libseccomp-2.5.0 to work but runc still works with older
libseccomp if the seccomp policy does not use the SCMP_ACT_NOTIFY
action.
A new synchronization step between runc[INIT] and runc run is introduced
to pass the seccomp fd. runc run fetches the seccomp fd with pidfd_get
from the runc[INIT] process and sends it to the seccomp agent using
SCM_RIGHTS.
As suggested by @kolyshkin, we also make writeSync() a wrapper of
writeSyncWithFd() and wrap the error there. To avoid pointless errors,
we made some existing code paths just return the error instead of
re-wrapping it. If we don't do it, error will look like:
writing syncT <act>: writing syncT: <err>
By adjusting the code path, now they just look like this
writing syncT <act>: <err>
Signed-off-by: Alban Crequy <alban@kinvolk.io>
Signed-off-by: Rodrigo Campos <rodrigo@kinvolk.io>
Co-authored-by: Rodrigo Campos <rodrigo@kinvolk.io>
This removes libcontainer's own error wrapping system, consisting of a
few types and functions, aimed at typization, wrapping and unwrapping
of errors, as well as saving error stack traces.
Since Go 1.13 now provides its own error wrapping mechanism and a few
related functions, it makes sense to switch to it.
While doing that, improve some error messages so that they start
with "error", "unable to", or "can't".
A few things that are worth mentioning:
1. We lose stack traces (which were never shown anyway).
2. Users of libcontainer that relied on particular errors (like
ContainerNotExists) need to switch to using errors.Is with
the new errors defined in error.go.
3. encoding/json is unable to unmarshal the built-in error type,
so we have to introduce initError and wrap the errors into it
(basically passing the error as a string). This is the same
as it was before, just a tad simpler (actually the initError
is a type that got removed in commit afa844311; also suddenly
ierr variable name makes sense now).
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Do this for all errors except one from unix.*.
This fixes a bunch of errorlint warnings, like these
libcontainer/generic_error.go:25:15: type assertion on error will fail on wrapped errors. Use errors.As to check for specific errors (errorlint)
if le, ok := err.(Error); ok {
^
libcontainer/factory_linux_test.go:145:14: type assertion on error will fail on wrapped errors. Use errors.As to check for specific errors (errorlint)
lerr, ok := err.(Error)
^
libcontainer/state_linux_test.go:28:11: type assertion on error will fail on wrapped errors. Use errors.As to check for specific errors (errorlint)
_, ok := err.(*stateTransitionError)
^
libcontainer/seccomp/patchbpf/enosys_linux.go:88:4: switch on an error will fail on wrapped errors. Use errors.Is to check for specific errors (errorlint)
switch err {
^
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
This should result in no change when the error is printed, but make the
errors returned unwrappable, meaning errors.As and errors.Is will work.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
These were added in 244c9fc4 (*: console rewrite, 2016-06-04, #1018)
alongside procConsole and the associated handling. procConsole and
that handling were removed in 00a0ecf5 (Add separate console socket,
2017-03-02, #1356), but 00a0ecf5 missed this comment.
Signed-off-by: W. Trevor King <wking@tremily.us>
This implements {createTTY, detach} and all of the combinations and
negations of the two that were previously implemented. There are some
valid questions about out-of-OCI-scope topics like !createTTY and how
things should be handled (why do we dup the current stdio to the
process, and how is that not a security issue). However, these will be
dealt with in a separate patchset.
In order to allow for late console setup, split setupRootfs into the
"preparation" section where all of the mounts are created and the
"finalize" section where we pivot_root and set things as ro. In between
the two we can set up all of the console mountpoints and symlinks we
need.
We use two-stage synchronisation to ensures that when the syscalls are
reordered in a suboptimal way, an out-of-place read() on the parentPipe
will not gobble the ancilliary information.
This patch is part of the console rewrite patchset.
Signed-off-by: Aleksa Sarai <asarai@suse.de>
To make the code cleaner, and more clear, refactor the syncT handling
used when creating the `runc init` process. In addition, document the
state changes so that people actually understand what is going on.
Rather than only using syncT for the standard initProcess, use it for
both initProcess and setnsProcess. This removes some special cases, as
well as allowing for the use of syncT with setnsProcess.
Also remove a bunch of the boilerplate around syncT handling.
This patch is part of the console rewrite patchset.
Signed-off-by: Aleksa Sarai <asarai@suse.de>
Aleksa Sarai