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4749 commits

Author SHA1 Message Date
Seth Hoenig 5138c5b99e
client: do not disable memory swappiness if kernel does not support it (#17625)
* client: do not disable memory swappiness if kernel does not support it

This PR adds a workaround for very old Linux kernels which do not support
the memory swappiness interface file. Normally we write a "0" to the file
to explicitly disable swap. In the case the kernel does not support it,
give libcontainer a nil value so it does not write anything.

Fixes #17448

* client: detect swappiness by writing to the file

* fixup changelog

Co-authored-by: James Rasell <jrasell@users.noreply.github.com>

---------

Co-authored-by: James Rasell <jrasell@users.noreply.github.com>
2023-06-22 09:36:31 -05:00
VishnuJin 67efb19e94
fingerprint: added windows os.build attribute to host fingerprint (#17576) 2023-06-21 10:53:50 -04:00
Patric Stout 4767d44b94
Fix DevicesSets being removed when cpusets are reloaded with cgroup v2 (#17535)
* Fix DevicesSets being removed when cpusets are reloaded with cgroup v2

This meant that if any allocation was created or removed, all
active DevicesSets were removed from all cgroups of all tasks.

This was most noticeable with "exec" and "raw_exec", as it meant
they no longer had access to /dev files.

* e2e: add test for verifying cgroups do not interfere with access to devices

---------

Co-authored-by: Seth Hoenig <shoenig@duck.com>
2023-06-15 09:39:36 -05:00
Tim Gross dc9fae34ca
node pools: add pool as label on client metrics (#17528)
This changeset adds the node pool as a label anywhere we're already emitting
labels with additional information such as node class or ID about the client.
2023-06-14 15:58:38 -04:00
Luiz Aoqui ec80d051d8
client: fix panic on alloc stop in non-Linux environments (#17515)
Provide a no-op implementation of the drivers.DriverNetoworkManager
interface to be used by systems that don't support network isolation and
prevent panics where a network manager is expected.
2023-06-14 10:22:38 -04:00
Seth Hoenig 557a6b4a5e
docker: stop network pause container of lost alloc after node restart (#17455)
This PR fixes a bug where the docker network pause container would not be
stopped and removed in the case where a node is restarted, the alloc is
moved to another node, the node comes back up. See the issue below for
full repro conditions.

Basically in the DestroyNetwork PostRun hook we would depend on the
NetworkIsolationSpec field not being nil - which is only the case
if the Client stays alive all the way from network creation to network
teardown. If the node is rebooted we lose that state and previously
would not be able to find the pause container to remove. Now, we manually
find the pause container by scanning them and looking for the associated
allocID.

Fixes #17299
2023-06-09 08:46:29 -05:00
Seth Hoenig 134e70cbab
client: fix client panic during drain cause by shutdown (#17450)
During shutdown of a client with drain_on_shutdown there is a race between
the Client ending the cgroup and the task's cpuset manager cleaning up
the cgroup. During the path traversal, skip anything we cannot read, which
avoids the nil DirEntry we try to dereference now.
2023-06-07 15:12:44 -05:00
Jerome Eteve c26f01eefd
client checks kernel module in /sys/module for WSL2 bridge networking (#17306) 2023-06-06 10:26:50 -04:00
Seth Hoenig d1d4d22f8e
test: ensure cpuset cgroup is setup before fingerprinting (#17428)
This PR fixes a racey test where we need to ensure the cpuset cgroup
is setup before trying to fingerprint it.
2023-06-05 14:15:00 -05:00
hashicorp-copywrite[bot] 0f4532f138
[COMPLIANCE] Add Copyright and License Headers (#17429)
Co-authored-by: hashicorp-copywrite[bot] <110428419+hashicorp-copywrite[bot]@users.noreply.github.com>
2023-06-05 13:23:59 -04:00
Luiz Aoqui 6039c18ab6
node pools: register a node in a node pool (#17405) 2023-06-02 17:50:50 -04:00
Tim Gross 06972fae0c
prioritized client updates (#17354)
The allocrunner sends several updates to the server during the early lifecycle
of an allocation and its tasks. Clients batch-up allocation updates every 200ms,
but experiments like the C2M challenge has shown that even with this batching,
servers can be overwhelmed with client updates during high volume
deployments. Benchmarking done in #9451 has shown that client updates can easily
represent ~70% of all Nomad Raft traffic.

Each allocation sends many updates during its lifetime, but only those that
change the `ClientStatus` field are critical for progressing a deployment or
kicking off a reschedule to recover from failures.

Add a priority to the client allocation sync and update the `syncTicker`
receiver so that we only send an update if there's a high priority update
waiting, or on every 5th tick. This means when there are no high priority
updates, the client will send updates at most every 1s instead of
200ms. Benchmarks have shown this can reduce overall Raft traffic by 10%, as
well as reduce client-to-server RPC traffic.

This changeset also switches from a channel-based collection of updates to a
shared buffer, so as to split batching from sending and prevent backpressure
onto the allocrunner when the RPC is slow. This doesn't have a major performance
benefit in the benchmarks but makes the implementation of the prioritized update
simpler.

Fixes: #9451
2023-05-31 15:34:16 -04:00
Luiz Aoqui bb2395031b
client: fix Consul version finterprint (#17349)
Consul v1.13.8 was released with a breaking change in the /v1/agent/self
endpoint version where a line break was being returned.

This caused the Nomad finterprint to fail because `NewVersion` errors on
parse.

This commit removes any extra space from the Consul version returned by
the API.
2023-05-30 11:07:57 -04:00
Seth Hoenig acfdf0f479
compliance: add headers with fixed copywrite tool (#17353)
Closes #17117
2023-05-30 09:20:32 -05:00
Charlie Voiselle 86e04a4c6c
[core] nil check and error handling for client status in heartbeat responses (#17316)
Add a nil check to constructNodeServerInfoResponse to manage an apparent race between deregister and client heartbeats. Fixes #17310
2023-05-25 16:04:54 -04:00
Lance Haig 568da5918b
cli: tls certs not created with correct SANs (#16959)
The `nomad tls cert` command did not create certificates with the correct SANs for
them to work with non default domain and region names. This changset updates the
code to support non default domains and regions in the certificates.
2023-05-22 09:31:56 -04:00
Seth Hoenig e04ff0d935
client: ignore restart issued to terminal allocations (#17175)
* client: ignore restart issued to terminal allocations

This PR fixes a bug where issuing a restart to a terminal allocation
would cause the allocation to run its hooks anyway. This was particularly
apparent with group_service_hook who would then register services but
then never deregister them - as the allocation would be effectively in
a "zombie" state where it is prepped to run tasks but never will.

* e2e: add e2e test for alloc restart zombies

* cl: tweak text

Co-authored-by: Tim Gross <tgross@hashicorp.com>

---------

Co-authored-by: Tim Gross <tgross@hashicorp.com>
2023-05-16 10:19:41 -05:00
Tim Gross 6814e8e6d9
drivers: make internal DisableLogCollection capability public (#17196)
The `DisableLogCollection` capability was introduced as an experimental
interface for the Docker driver in 0.10.4. The interface has been stable and
allowing third-party task drivers the same capability would be useful for those
drivers that don't need the additional overhead of logmon.

This PR only makes the capability public. It doesn't yet add it to the
configuration options for the other internal drivers.

Fixes: #14636 #15686
2023-05-16 09:16:03 -04:00
Tim Gross d018fcbff7
allocrunner: provide factory function so we can build mock ARs (#17161)
Tools like `nomad-nodesim` are unable to implement a minimal implementation of
an allocrunner so that we can test the client communication without having to
lug around the entire allocrunner/taskrunner code base. The allocrunner was
implemented with an interface specifically for this purpose, but there were
circular imports that made it challenging to use in practice.

Move the AllocRunner interface into an inner package and provide a factory
function type. Provide a minimal test that exercises the new function so that
consumers have some idea of what the minimum implementation required is.
2023-05-12 13:29:44 -04:00
Tim Gross 9ed75e1f72
client: de-duplicate alloc updates and gate during restore (#17074)
When client nodes are restarted, all allocations that have been scheduled on the
node have their modify index updated, including terminal allocations. There are
several contributing factors:

* The `allocSync` method that updates the servers isn't gated on first contact
  with the servers. This means that if a server updates the desired state while
  the client is down, the `allocSync` races with the `Node.ClientGetAlloc`
  RPC. This will typically result in the client updating the server with "running"
  and then immediately thereafter "complete".

* The `allocSync` method unconditionally sends the `Node.UpdateAlloc` RPC even
  if it's possible to assert that the server has definitely seen the client
  state. The allocrunner may queue-up updates even if we gate sending them. So
  then we end up with a race between the allocrunner updating its internal state
  to overwrite the previous update and `allocSync` sending the bogus or duplicate
  update.

This changeset adds tracking of server-acknowledged state to the
allocrunner. This state gets checked in the `allocSync` before adding the update
to the batch, and updated when `Node.UpdateAlloc` returns successfully. To
implement this we need to be able to equality-check the updates against the last
acknowledged state. We also need to add the last acknowledged state to the
client state DB, otherwise we'd drop unacknowledged updates across restarts.

The client restart test has been expanded to cover a variety of allocation
states, including allocs stopped before shutdown, allocs stopped by the server
while the client is down, and allocs that have been completely GC'd on the
server while the client is down. I've also bench tested scenarios where the task
workload is killed while the client is down, resulting in a failed restore.

Fixes #16381
2023-05-11 09:05:24 -04:00
Seth Hoenig 6f4992ef29
client: unveil /etc/ssh/ssh_known_hosts for artifact downloads (#17122)
This PR fixes a bug where nodes configured with populated
/etc/ssh/ssh_known_hosts files would be unable to read them during
artifact downloading.

Fixes #17086
2023-05-09 09:43:52 -05:00
Daniel Bennett a7ed6f5c53
full task cleanup when alloc prerun hook fails (#17104)
to avoid leaking task resources (e.g. containers,
iptables) if allocRunner prerun fails during
restore on client restart.

now if prerun fails, TaskRunner.MarkFailedKill()
will only emit an event, mark the task as failed,
and cancel the tr's killCtx, so then ar.runTasks()
-> tr.Run() can take care of the actual cleanup.

removed from (formerly) tr.MarkFailedDead(),
now handled by tr.Run():
 * set task state as dead
 * save task runner local state
 * task stop hooks

also done in tr.Run() now that it's not skipped:
 * handleKill() to kill tasks while respecting
   their shutdown delay, and retrying as needed
   * also includes task preKill hooks
 * clearDriverHandle() to destroy the task
   and associated resources
 * task exited hooks
2023-05-08 13:17:10 -05:00
Tim Gross 17bd930ca9
logs: fix missing allocation logs after update to Nomad 1.5.4 (#17087)
When the server restarts for the upgrade, it loads the `structs.Job` from the
Raft snapshot/logs. The jobspec has long since been parsed, so none of the
guards around the default value are in play. The empty field value for `Enabled`
is the zero value, which is false.

This doesn't impact any running allocation because we don't replace running
allocations when either the client or server restart. But as soon as any
allocation gets rescheduled (ex. you drain all your clients during upgrades),
it'll be using the `structs.Job` that the server has, which has `Enabled =
false`, and logs will not be collected.

This changeset fixes the bug by adding a new field `Disabled` which defaults to
false (so that the zero value works), and deprecates the old field.

Fixes #17076
2023-05-04 16:01:18 -04:00
Seth Hoenig e9fec4ebc8
connect: remove unusable path for fallback envoy image names (#17044)
This PR does some cleanup of an old code path for versions of Consul that
did not support reporting the supported versions of Envoy in its API. Those
versions are no longer supported for years at this point, and the fallback
version of envoy hasn't been supported by any version of Consul for almost
as long. Remove this code path that is no longer useful.
2023-05-02 09:48:44 -05:00
Seth Hoenig e8d53ea30b
connect: use explicit docker.io prefix in default envoy image names (#17045)
This PR modifies references to the envoyproxy/envoy docker image to
explicitly include the docker.io prefix. This does not affect existing
users, but makes things easier for Podman users, who otherwise need to
specify the full name because Podman does not default to docker.io
2023-05-02 09:27:48 -05:00
Luiz Aoqui 7b5a8f1fb0
Revert "hashicorp/go-msgpack v2 (#16810)" (#17047)
This reverts commit 8a98520d56eed3848096734487d8bd3eb9162a65.
2023-05-01 17:18:34 -04:00
Seth Hoenig 86f6a38867
connect: do not restrict auto envoy version to docker task driver (#17041)
This PR updates the envoy_bootstrap_hook to no longer disable itself if
the task driver in use is not docker. In other words, make it work for
podman and other image based task drivers. The hook now only checks that

1. the task is a connect sidecar
2. the task.config block contains an "image" field
2023-05-01 15:07:35 -05:00
Seth Hoenig 753c17c9de
services: un-mark group services as deregistered if restart hook runs (#16905)
* services: un-mark group services as deregistered if restart hook runs

This PR may fix a bug where group services will never be deregistered if the
group undergoes a task restart.

* e2e: add test case for restart and deregister group service

* cl: add cl

* e2e: add wait for service list call
2023-04-24 14:24:51 -05:00
Tim Gross 72cbe53f19
logs: allow disabling log collection in jobspec (#16962)
Some Nomad users ship application logs out-of-band via syslog. For these users
having `logmon` (and `docker_logger`) running is unnecessary overhead. Allow
disabling the logmon and pointing the task's stdout/stderr to /dev/null.

This changeset is the first of several incremental improvements to log
collection short of full-on logging plugins. The next step will likely be to
extend the internal-only task driver configuration so that cluster
administrators can turn off log collection for the entire driver.

---

Fixes: #11175

Co-authored-by: Thomas Weber <towe75@googlemail.com>
2023-04-24 10:00:27 -04:00
valodzka 379497a484
fix host port handling for ipv6 (#16723) 2023-04-20 19:53:20 -07:00
Etienne Bruines 1e3531b978
cni: fix plugin fingerprinting versions (#16776)
CNI plugins v1.2.0 and above output a second line, containing supported protocol versions.
2023-04-20 18:44:39 -07:00
astudentofblake 42c4c8d5ea
fix: added landlock access to /usr/libexec for getter (#16900) 2023-04-20 11:16:04 -05:00
Luiz Aoqui fb588fcbb8
allocrunner: prevent panic on network manager (#16921) 2023-04-18 13:39:13 -07:00
Ian Fijolek 619f49afcf
hashicorp/go-msgpack v2 (#16810)
* Upgrade from hashicorp/go-msgpack v1.1.5 to v2.1.0

Fixes #16808

* Update hashicorp/net-rpc-msgpackrpc to v2 to match go-msgpack

* deps: use go-msgpack v2.0.0

go-msgpack v2.1.0 includes some code changes that we will need to
investigate furthere to assess its impact on Nomad, so keeping this
dependency on v2.0.0 for now since it's no-op.

---------

Co-authored-by: Luiz Aoqui <luiz@hashicorp.com>
2023-04-17 17:02:05 -04:00
Seth Hoenig 92d4a05534
users: eliminate nobody user memoization (#16904)
This PR eliminates code specific to looking up and caching the uid/gid/user.User
object associated with the nobody user in an init block. This code existed before
adding the generic users cache and was meant to optimize the one search path we
knew would happen often. Now that we have the cache, seems reasonable to eliminate
this init block and use the cache instead like for any other user.

Also fixes a constraint on the podman (and other) drivers, where building without
CGO became problematic on some OS like Fedora IoT where the nobody user cannot
be found with the pure-Go standard library.

Fixes github.com/hashicorp/nomad-driver-podman/issues/228
2023-04-17 12:30:30 -05:00
Tim Gross 62548616d4
client: allow drain_on_shutdown configuration (#16827)
Adds a new configuration to clients to optionally allow them to drain their
workloads on shutdown. The client sends the `Node.UpdateDrain` RPC targeting
itself and then monitors the drain state as seen by the server until the drain
is complete or the deadline expires. If it loses connection with the server, it
will monitor local client status instead to ensure allocations are stopped
before exiting.
2023-04-14 15:35:32 -04:00
James Rasell bc01d47071
consul/connect: fixed a bug where restarting proxy tasks failed. (#16815)
The first start of a Consul Connect proxy sidecar triggers a run
of the envoy_version hook which modifies the task config image
entry. The modification takes into account a number of factors to
correctly populate this. Importantly, once the hook has run, it
marks itself as done so the taskrunner will not execute it again.

When the client receives a non-destructive update for the
allocation which the proxy sidecar is a member of, it will update
and overwrite the task definition within the taskerunner. In doing
so it overwrite the modification performed by the hook. If the
allocation is restarted, the envoy_version hook will be skipped as
it previously marked itself as done, and therefore the sidecar
config image is incorrect and causes a driver error.

The fix removes the hook in marking itself as done to the view of
the taskrunner.
2023-04-11 15:56:03 +01:00
Seth Hoenig ba728f8f97
api: enable support for setting original job source (#16763)
* api: enable support for setting original source alongside job

This PR adds support for setting job source material along with
the registration of a job.

This includes a new HTTP endpoint and a new RPC endpoint for
making queries for the original source of a job. The
HTTP endpoint is /v1/job/<id>/submission?version=<version> and
the RPC method is Job.GetJobSubmission.

The job source (if submitted, and doing so is always optional), is
stored in the job_submission memdb table, separately from the
actual job. This way we do not incur overhead of reading the large
string field throughout normal job operations.

The server config now includes job_max_source_size for configuring
the maximum size the job source may be, before the server simply
drops the source material. This should help prevent Bad Things from
happening when huge jobs are submitted. If the value is set to 0,
all job source material will be dropped.

* api: avoid writing var content to disk for parsing

* api: move submission validation into RPC layer

* api: return an error if updating a job submission without namespace or job id

* api: be exact about the job index we associate a submission with (modify)

* api: reword api docs scheduling

* api: prune all but the last 6 job submissions

* api: protect against nil job submission in job validation

* api: set max job source size in test server

* api: fixups from pr
2023-04-11 08:45:08 -05:00
Michael Schurter a407cbb626
Merge pull request #16836 from hashicorp/compliance/add-headers
[COMPLIANCE] Add Copyright and License Headers
2023-04-10 16:32:03 -07:00
Daniel Bennett fa33ee567a
gracefully recover tasks that use csi node plugins (#16809)
new WaitForPlugin() called during csiHook.Prerun,
so that on startup, clients can recover running
tasks that use CSI volumes, instead of them being
terminated and rescheduled because they need a
node plugin that is "not found" *yet*, only because
the plugin task has not yet been recovered.
2023-04-10 17:15:33 -05:00
hashicorp-copywrite[bot] 005636afa0 [COMPLIANCE] Add Copyright and License Headers 2023-04-10 15:36:59 +00:00
Tim Gross 1335543731
ephemeral disk: migrate should imply sticky (#16826)
The `ephemeral_disk` block's `migrate` field allows for best-effort migration of
the ephemeral disk data to new nodes. The documentation says the `migrate` field
is only respected if `sticky=true`, but in fact if client ACLs are not set the
data is migrated even if `sticky=false`.

The existing behavior when client ACLs are disabled has existed since the early
implementation, so "fixing" that case now would silently break backwards
compatibility. Additionally, having `migrate` not imply `sticky` seems
nonsensical: it suggests that if we place on a new node we migrate the data but
if we place on the same node, we throw the data away!

Update so that `migrate=true` implies `sticky=true` as follows:

* The failure mode when client ACLs are enabled comes from the server not passing
  along a migration token. Update the server so that the server provides a
  migration token whenever `migrate=true` and not just when `sticky=true` too.
* Update the scheduler so that `migrate` implies `sticky`.
* Update the client so that we check for `migrate || sticky` where appropriate.
* Refactor the E2E tests to move them off the old framework and make the intention
  of the test more clear.
2023-04-07 16:33:45 -04:00
James Rasell 15eee99db4
client: ensure envoy version hook uses all pointer receiver funcs. (#16813) 2023-04-06 14:47:00 +01:00
the-nando f541f2e59b
Do not set attributes when spawning the getter child (#16791)
* Do not set attributes when spawning the getter child

* Cleanup

* Cleanup

---------

Co-authored-by: the-nando <the-nando@invalid.local>
2023-04-05 11:47:51 -05:00
Tim Gross 118b703164
CSI: set mounts in alloc hook resources atomically (#16722)
The allocrunner has a facility for passing data written by allocrunner hooks to
taskrunner hooks. Currently the only consumers of this facility are the
allocrunner CSI hook (which writes data) and the taskrunner volume hook (which
reads that same data).

The allocrunner hook for CSI volumes doesn't set the alloc hook resources
atomically. Instead, it gets the current resources and then writes a new version
back. Because the CSI hook is currently the only writer and all readers happen
long afterwards, this should be safe but #16623 shows there's some sequence of
events during restore where this breaks down.

Refactor hook resources so that hook data is accessed via setters and getters
that hold the mutex.
2023-04-03 11:03:36 -04:00
Seth Hoenig 87f4b71df0
client/fingerprint: correctly fingerprint E/P cores of Apple Silicon chips (#16672)
* client/fingerprint: correctly fingerprint E/P cores of Apple Silicon chips

This PR adds detection of asymetric core types (Power & Efficiency) (P/E)
when running on M1/M2 Apple Silicon CPUs. This functionality is provided
by shoenig/go-m1cpu which makes use of the Apple IOKit framework to read
undocumented registers containing CPU performance data. Currently working
on getting that functionality merged upstream into gopsutil, but gopsutil
would still not support detecting P vs E cores like this PR does.

Also refactors the CPUFingerprinter code to handle the mixed core
types, now setting power vs efficiency cpu attributes.

For now the scheduler is still unaware of mixed core types - on Apple
platforms tasks cannot reserve cores anyway so it doesn't matter, but
at least now the total CPU shares available will be correct.

Future work should include adding support for detecting P/E cores on
the latest and upcoming Intel chips, where computation of total cpu shares
is currently incorrect. For that, we should also include updating the
scheduler to be core-type aware, so that tasks of resources.cores on Linux
platforms can be assigned the correct number of CPU shares for the core
type(s) they have been assigned.

node attributes before

cpu.arch                  = arm64
cpu.modelname             = Apple M2 Pro
cpu.numcores              = 12
cpu.reservablecores       = 0
cpu.totalcompute          = 1000

node attributes after

cpu.arch                  = arm64
cpu.frequency.efficiency  = 2424
cpu.frequency.power       = 3504
cpu.modelname             = Apple M2 Pro
cpu.numcores.efficiency   = 4
cpu.numcores.power        = 8
cpu.reservablecores       = 0
cpu.totalcompute          = 37728

* fingerprint/cpu: follow up cr items
2023-03-28 08:27:58 -05:00
Seth Hoenig 07543f8bdf
nsd: always set deregister flag after deregistration of group (#16289)
* services: always set deregister flag after deregistration of group

This PR fixes a bug where the group service hook's deregister flag was
not set in some cases, causing the hook to attempt deregistrations twice
during job updates (alloc replacement).

In the tests ... we used to assert on the wrong behvior (remove twice) which
has now been corrected to assert we remove only once.

This bug was "silent" in the Consul provider world because the error logs for
double deregistration only show up in Consul logs; with the Nomad provider the
error logs are in the Nomad agent logs.

* services: cleanup group service hook tests
2023-03-17 09:44:21 -05:00
Tim Gross ec47b245d0
client: don't use Status RPC for Consul discovery (#16490)
In #16217 we switched clients using Consul discovery to the `Status.Members`
endpoint for getting the list of servers so that we're using the correct
address. This endpoint has an authorization gate, so this fails if the anonymous
policy doesn't have `node:read`. We also can't check the `AuthToken` for the
request for the client secret, because the client hasn't yet registered so the
server doesn't have anything to compare against.

Instead of hitting the `Status.Peers` or `Status.Members` RPC endpoint, use the
Consul response directly. Update the `registerNode` method to handle the list of
servers we get back in the response; if we get a "no servers" or "no path to
region" response we'll kick off discovery again and retry immediately rather
than waiting 15s.
2023-03-16 15:38:33 -04:00
Seth Hoenig 5b1970468e
artifact: git needs more files for private repositories (#16508)
* landlock: git needs more files for private repositories

This PR fixes artifact downloading so that git may work when cloning from
private repositories. It needs

- file read on /etc/passwd
- dir read on /root/.ssh
- file write on /root/.ssh/known_hosts

Add these rules to the landlock rules for the artifact sandbox.

* cr: use nonexistent instead of devnull

Co-authored-by: Michael Schurter <mschurter@hashicorp.com>

* cr: use go-homdir for looking up home directory

* pr: pull go-homedir into explicit require

* cr: fixup homedir tests in homeless root cases

* cl: fix root test for real

---------

Co-authored-by: Michael Schurter <mschurter@hashicorp.com>
2023-03-16 12:22:25 -05:00
Seth Hoenig d2e8fb626a
artifact: do not set process attributes on darwin (#16511)
This PR fixes the non-root macOS use case where artifact downloads
stopped working. It seems setting a Credential on a SysProcAttr
used by the exec package will always cause fork/exec to fail -
even if the credential contains our own UID/GID or nil UID/GID.

Technically we do not need to set this as the child process will
inherit the parent UID/GID anyway... and not setting it makes
things work again ... /shrug
2023-03-16 11:31:18 -05:00