Keyword being "Try".
Instead of sleeping a fixed duration and then resuming with
the assumption that the launched process is up, we now poll
till the launched process is seen to be up.
PiperOrigin-RevId: 956087777
There is already some support for privileged executables before this change:
file capabilities were taken into account when creating new processes inside
the sandbox from external instigation (but not during execve(2)). set-user-id
and set-group-id bits were never taken into account, and the Sentry behaved
as if NO_NEW_PRIVS is always true. After this change, execve(2) and the
external Exec entry point both take the set-user(group)-id bits and file
capabilities into account.
Because NO_NEW_PRIVS can no longer be assumed to be always set, a couple of
extra checks to prevent privilege elevation during execve(2) are needed:
the presence of a ptracer and the use of a shared fsContext. Moreover,
execve had to be serialized with seccomp(2) when it is syncing filters to
all threads in a group. Serializing execve with PTRACE_ATTACH and seccomp
required some Task runState gymnastics.
Task dumpability is reset when privilege elevation takes place and privilege
elevation is denied for binaries living on nosuid mounts. To fix an old bug
where some aux vectors were populated using data from the old pre-execve
creds, the computation of the (file-privilege-augmented) creds during execve
now takes place before the stack for the new program is set up.
gvisor users who thus far have exec'd into the sandbox with UID as (sandbox)
root will lose the caps an all-powerful namespace root'd have if: 1) the binary
is a suid/guid binary 2) the owner of the binary is host root and there is
no mapping for host root in the host user namespace of the sandbox. To avoid
this surprise, the suid/sgid bits are ignored by default. Users can opt-in
via the --allow-suid flag.
One result of this change is that sudo now works inside the sandbox.
PiperOrigin-RevId: 794414101
All the following changes are compatible with what Linux does.
- Do not attempt to apply file capabilities when it is not present.
- If the rootID specified in v3 file capability struct does not own the
current userns, then file capabilities are not applied.
- While applying file capabilities, EPERM is only returned if
VFS_CAP_FLAGS_EFFECTIVE is set.
- Re-raise capabilities of root user as per capabilities(7). Compare
security/commoncap.c:handle_privileged_root().
PiperOrigin-RevId: 761725759
This allows writing capabilities only to "security.capability" within the
security namespace. In goferfs, this is disallowed to prevent writes from
propagating to the underlying host filesystem.
PiperOrigin-RevId: 756009863
This change adds a layer of abstraction around the internal Docker APIs,
and eliminates all direct dependencies on Dockerfiles in the infrastructure.
A subsequent change will automated the generation of local images (with
efficient caching). Note that this change drops the use of bazel container
rules, as that experiment does not seem to be viable.
PiperOrigin-RevId: 308095430
It's possible to execute the command that checks user's
$HOME dir before the user is created. Move the code that
creates the user inside exec so it can be serialized.
PiperOrigin-RevId: 302986184
Adds two tests. One to make sure that $HOME is set when starting a container
via 'docker run' and one to make sure that $HOME is set for each container in a
multi-container sandbox.
Issue #701
PiperOrigin-RevId: 273395763
'docker exec' was getting CAP_NET_RAW even when --net-raw=false
because it was not filtered out from when copying container's
capabilities.
PiperOrigin-RevId: 272260451
The simple test script has gotten out of control. Shard this script into
different pieces and attempt to impose order on overall test structure. This
change helps lay some of the foundations for future improvements.
* The runsc/test directories are moved into just test/.
* The runsc/test/testutil package is split into logical pieces.
* The scripts/ directory contains new top-level targets.
* Each test is now responsible for building targets it requires.
* The install functionality is moved into `runsc` itself for simplicity.
* The existing kokoro run_tests.sh file now just calls all (can be split).
After this change is merged, I will create multiple distinct workflows for
Kokoro, one for each of the scripts currently targeted by `run_tests.sh` today,
which should dramatically reduce the time-to-run for the Kokoro tests, and
provides a better foundation for further improvements to the infrastructure.
PiperOrigin-RevId: 267081397
