1. bump golang.org/x/sys to v0.6.0;
2. bump golang.org/x/net to v0.8.0
3. require Go 1.17.
Newer x/sys is needed to fix [1].
Go 1.17 is needed because x/sys/unix is using unsafe.Slice which
requires go1.17 or later.
This reuses parts of main commit a0f8847e2a.
[1] https://github.com/opencontainers/runc/issues/3715
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
We need to update the eBPF library so that we can get the raw syscall
errors from bpf(2) syscalls using errors.Is.
Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
The main change is the switch to Go 1.13-style "%w" error wrapping,
dropping one of the github.com/pkg/errors dependencies we have left.
Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
The `errors.Is(err, unix.EINVAL)` check in `haveBpfProgReplace()` was
broken because the `cilium/ebpf` library did not "wrap" errors.
https://github.com/cilium/ebpf/blob/v0.6.0/link/program.go#L72
So the eBPF support of runc was broken for kernel prior to 5.6.
This commit bumps up cilium/ebpf to contain cilium/ebpf PR 320.
Fix opencontainers/runc issue 3008
Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>
full diff: https://github.com/cilium/ebpf/compare/v0.4.0...v0.5.0
Breaking changes
------------------------------------------
All LoadPinned*() functions now take LoadPinOptions to control loader behaviour.
Simply pass nil to load with default options.
- LoadPinnedMap()
- LoadPinnedProgram()
- LoadPinnedCgroup()
- LoadPinnedIter()
- LoadPinnedRawLink()
- LoadPinnedNetNs()
Bug fixes
------------------------------------------
- Program.IsPinned() now behaves correctly on maps loaded from bpffs
- Map.Pin() no longer clobbers the destination file if it already exists
Features
------------------------------------------
- Attaching to k(ret)probes and tracepoints can now be done with link.Kprobe(),
link.Kretprobe() and link.Tracepoint()
- Programs of type Kprobe automatically get their KernelVersion fields populated
by detecting the kernel version at runtime
- MapOptions now contains a LoadPinOptions
- ProgSpec now contains a Flags field, adding support for BPF_F_SLEEPABLE
- Made BTF map loader more flexible by looping over Vars in a BTF data section
- Pinned Maps and Programs can now be loaded from bpffs in read-or write-only mode
- Added golangci-lint project configuration, running in CI
Examples
------------------------------------------
kprobe and tracepoint examples updated to use the new link.Kprobe() and link.Tracepoint() API
There is now an example for how to attach eBPF programs to uprobes
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Caught by golangci-lint when enabling golint:
libcontainer/cgroups/ebpf/ebpf.go:35:12: SA1019: prog.Attach is deprecated: use link.RawAttachProgram instead. (staticcheck)
if err := prog.Attach(dirFD, ebpf.AttachCGroupDevice, unix.BPF_F_ALLOW_MULTI); err != nil {
^
libcontainer/cgroups/ebpf/ebpf.go:39:13: SA1019: prog.Detach is deprecated: use link.RawDetachProgram instead. (staticcheck)
if err := prog.Detach(dirFD, ebpf.AttachCGroupDevice, unix.BPF_F_ALLOW_MULTI); err != nil {
^
Worth noting that we currently call prog.Detach() with unix.BPF_F_ALLOW_MULTI;
https://github.com/golang/sys/blob/22da62e12c0cd9c1da93581e1113ca4d82a5be14/unix/zerrors_linux.go#L178
BPF_F_ALLOW_MULTI = 0x2
Looking at the source code for prog.Detach(); https://github.com/cilium/ebpf/blob/v0.4.0/prog.go#L579-L581,
this would _always_ produce an error:
if flags != 0 {
return errors.New("flags must be zero")
}
Note that the flags parameter is not used (except for that validation)
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
This updates handling of capabilities to match the updated runtime specification,
in https://github.com/opencontainers/runtime-spec/pull/1094.
Prior to that change, the specification required runtimes to produce a (fatal)
error if a container configuration requested capabilities that could not be
granted (either the capability is "unknown" to the runtime, not supported by the
kernel version in use, or not available in the environment that the runtime
operates in).
This caused problems in situations where the runtime was running in a restricted
environment (for example, docker-in-docker), or if there is a mismatch between
the list of capabilities known by higher-level runtimes and the OCI runtime.
Some examples:
- Kernel 5.8 introduced CAP_PERFMON, CAP_BPF, and CAP_CHECKPOINT_RESTORE
capabilities. Docker 20.10.0 ("higher level runtime") shipped with
an updated list of capabilities, and when creating a "privileged" container,
would determine what capabilities are known by the kernel in use, and request
all those capabilities (by including them in the container config).
However, runc did not yet have an updated list of capabilities, and therefore
reject the container specification, producing an error because the new
capabilities were "unknown".
- When running nested containers, for example, when running docker-in-docker,
the "inner" container may be using a more recent version of docker than the
"outer" container. In this situation, the "outer" container may be missing
capabilities that the inner container expects to be supported (based on
kernel version). However, starting the container would fail, because the OCI
runtime could not grant those capabilities (them not being available in the
environment it's running in).
WARN (but otherwise ignore) capabilities that cannot be granted
--------------------------------------------------------------------------------
This patch changes the handling to WARN (but otherwise ignore) capabilities that
are requested in the container config, but cannot be granted, alleviating higher
level runtimes to detect what capabilities are supported (by the kernel, and
in the current environment), as well as avoiding failures in situations where
the higher-level runtime is aware of capabilities that are not (yet) supported
by runc.
Impact on security
--------------------------------------------------------------------------------
Given that `capabilities` is an "allow-list", ignoring unknown capabilities does
not impose a security risk; worst case, a container does not get all requested
capabilities granted and, as a result, some actions may fail.
Backward-compatibility
--------------------------------------------------------------------------------
This change should be fully backward compatible. Higher-level runtimes that
already dynamically adjust the list of requested capabilities can continue to do
so. Runtimes that do not adjust will see an improvement (containers can start
even if some of the requested capabilities are not granted). Container processes
MAY fail (as described in "impact on security"), but users can debug this
situation either by looking at the warnings produces by the OCI runtime, or using
tools such as `capsh` / `libcap` to get the list of actual capabilities in the
container.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Switch from github.com/golang/protobuf (which appears to be obsoleted)
to google.golang.org/protobuf (which appears to be a replacement).
This needs a bump to go-criu v5.
[v2: fix debug print in criuSwrk]
[v3: switch to go-criu v5]
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
full diff: https://github.com/cilium/ebpf/compare/v0.1.0...v0.2.0
- btf: add go-fuzz targets
- btf: avoid Type copy in FuncProto.walk
- btf: check err in loadSpecFromVmlinux
- btf: handle type name flavours
- CI: test on 5.9 kernel
- cmd/bpf2go: output ELF .o next to the .go file
- link: add AttachSkLookup
- Remove two unused functions
- Support LSM attach
- use buffered I/O to cut down on read syscalls
- Various doc link fixes
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
* cpuset.cpus -> AllowedCPUs
* cpuset.mems -> AllowedMemoryNodes
No test for cgroup v2 resources.unified override, as this requires a
separate test case, and all the unified resources are handled uniformly
so there's little sense to test all parameters.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Kir Kolyshkin