forked from lix-project/lix
Merge pull request #3600 from NixOS/auto-uid-allocation
Automatic UID allocation
This commit is contained in:
Eelco Dolstra
GitHub
commit
fbc53e97ed
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@ -10,3 +10,45 @@
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This avoids a lot of spurious errors where some benign strings end-up having
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a context just because they are read from a store path
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([#7260](https://github.com/NixOS/nix/pull/7260)).
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* Nix can now automatically pick UIDs for builds, removing the need to
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create `nixbld*` user accounts. These UIDs are allocated starting at
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872415232 (0x34000000) on Linux and 56930 on macOS.
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This is an experimental feature. To enable it, add the following to
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`nix.conf`:
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```
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extra-experimental-features = auto-allocate-uids
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auto-allocate-uids = true
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```
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* On Linux, Nix can now run builds in a user namespace where the build
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runs as root (UID 0) and has 65,536 UIDs available. This is
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primarily useful for running containers such as `systemd-nspawn`
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inside a Nix build. For an example, see
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https://github.com/NixOS/nix/blob/67bcb99700a0da1395fa063d7c6586740b304598/tests/systemd-nspawn.nix.
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A build can enable this by requiring the `uid-range` system feature,
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i.e. by setting the derivation attribute
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```
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requiredSystemFeatures = [ "uid-range" ];
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```
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The `uid-range` system feature requires the `auto-allocate-uids`
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setting to be enabled (see above).
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* On Linux, Nix has experimental support for running builds inside a
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cgroup. It can be enabled by adding
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```
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extra-experimental-features = cgroups
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use-cgroups = true
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```
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to `nix.conf`. Cgroups are required for derivations that require the
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`uid-range` system feature.
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* `nix build --json` now prints some statistics about top-level
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derivations, such as CPU statistics when cgroups are enabled.
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@ -506,6 +506,12 @@
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overlay = self.overlays.default;
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});
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tests.containers = (import ./tests/containers.nix rec {
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system = "x86_64-linux";
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inherit nixpkgs;
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overlay = self.overlays.default;
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});
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tests.setuid = nixpkgs.lib.genAttrs
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["i686-linux" "x86_64-linux"]
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(system:
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@ -931,7 +931,7 @@ std::vector<std::pair<std::shared_ptr<Installable>, BuiltPathWithResult>> Instal
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case Realise::Outputs: {
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if (settings.printMissing)
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printMissing(store, pathsToBuild, lvlInfo);
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printMissing(store, pathsToBuild, lvlInfo);
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for (auto & buildResult : store->buildPathsWithResults(pathsToBuild, bMode, evalStore)) {
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if (!buildResult.success())
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@ -5,7 +5,7 @@
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#include <string>
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#include <chrono>
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#include <optional>
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namespace nix {
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@ -78,6 +78,9 @@ struct BuildResult
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was repeated). */
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time_t startTime = 0, stopTime = 0;
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/* User and system CPU time the build took. */
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std::optional<std::chrono::microseconds> cpuUser, cpuSystem;
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bool success()
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{
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return status == Built || status == Substituted || status == AlreadyValid || status == ResolvesToAlreadyValid;
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@ -886,6 +886,14 @@ void DerivationGoal::buildDone()
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cleanupPostChildKill();
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if (buildResult.cpuUser && buildResult.cpuSystem) {
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debug("builder for '%s' terminated with status %d, user CPU %.3fs, system CPU %.3fs",
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worker.store.printStorePath(drvPath),
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status,
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((double) buildResult.cpuUser->count()) / 1000000,
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((double) buildResult.cpuSystem->count()) / 1000000);
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}
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bool diskFull = false;
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try {
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@ -14,6 +14,7 @@
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#include "topo-sort.hh"
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#include "callback.hh"
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#include "json-utils.hh"
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#include "cgroup.hh"
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#include <regex>
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#include <queue>
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@ -129,26 +130,44 @@ void LocalDerivationGoal::killChild()
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if (pid != -1) {
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worker.childTerminated(this);
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if (buildUser) {
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/* If we're using a build user, then there is a tricky
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race condition: if we kill the build user before the
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child has done its setuid() to the build user uid, then
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it won't be killed, and we'll potentially lock up in
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pid.wait(). So also send a conventional kill to the
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child. */
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::kill(-pid, SIGKILL); /* ignore the result */
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buildUser->kill();
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pid.wait();
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} else
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pid.kill();
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/* If we're using a build user, then there is a tricky race
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condition: if we kill the build user before the child has
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done its setuid() to the build user uid, then it won't be
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killed, and we'll potentially lock up in pid.wait(). So
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also send a conventional kill to the child. */
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::kill(-pid, SIGKILL); /* ignore the result */
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assert(pid == -1);
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killSandbox(true);
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pid.wait();
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}
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DerivationGoal::killChild();
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}
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void LocalDerivationGoal::killSandbox(bool getStats)
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{
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if (cgroup) {
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#if __linux__
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auto stats = destroyCgroup(*cgroup);
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if (getStats) {
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buildResult.cpuUser = stats.cpuUser;
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buildResult.cpuSystem = stats.cpuSystem;
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}
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#else
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abort();
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#endif
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}
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else if (buildUser) {
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auto uid = buildUser->getUID();
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assert(uid != 0);
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killUser(uid);
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}
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}
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void LocalDerivationGoal::tryLocalBuild() {
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unsigned int curBuilds = worker.getNrLocalBuilds();
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if (curBuilds >= settings.maxBuildJobs) {
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@ -158,28 +177,46 @@ void LocalDerivationGoal::tryLocalBuild() {
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return;
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}
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/* If `build-users-group' is not empty, then we have to build as
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one of the members of that group. */
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if (settings.buildUsersGroup != "" && getuid() == 0) {
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#if defined(__linux__) || defined(__APPLE__)
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if (!buildUser) buildUser = std::make_unique<UserLock>();
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/* Are we doing a chroot build? */
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{
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auto noChroot = parsedDrv->getBoolAttr("__noChroot");
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if (settings.sandboxMode == smEnabled) {
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if (noChroot)
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throw Error("derivation '%s' has '__noChroot' set, "
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"but that's not allowed when 'sandbox' is 'true'", worker.store.printStorePath(drvPath));
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#if __APPLE__
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if (additionalSandboxProfile != "")
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throw Error("derivation '%s' specifies a sandbox profile, "
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"but this is only allowed when 'sandbox' is 'relaxed'", worker.store.printStorePath(drvPath));
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#endif
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useChroot = true;
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}
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else if (settings.sandboxMode == smDisabled)
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useChroot = false;
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else if (settings.sandboxMode == smRelaxed)
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useChroot = derivationType.isSandboxed() && !noChroot;
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}
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if (buildUser->findFreeUser()) {
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/* Make sure that no other processes are executing under this
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uid. */
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buildUser->kill();
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} else {
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auto & localStore = getLocalStore();
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if (localStore.storeDir != localStore.realStoreDir.get()) {
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#if __linux__
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useChroot = true;
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#else
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throw Error("building using a diverted store is not supported on this platform");
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#endif
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}
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if (useBuildUsers()) {
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if (!buildUser)
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buildUser = acquireUserLock(parsedDrv->useUidRange() ? 65536 : 1, useChroot);
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if (!buildUser) {
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if (!actLock)
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actLock = std::make_unique<Activity>(*logger, lvlWarn, actBuildWaiting,
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fmt("waiting for UID to build '%s'", yellowtxt(worker.store.printStorePath(drvPath))));
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worker.waitForAWhile(shared_from_this());
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return;
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}
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#else
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/* Don't know how to block the creation of setuid/setgid
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binaries on this platform. */
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throw Error("build users are not supported on this platform for security reasons");
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#endif
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}
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actLock.reset();
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@ -270,7 +307,7 @@ void LocalDerivationGoal::cleanupPostChildKill()
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malicious user from leaving behind a process that keeps files
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open and modifies them after they have been chown'ed to
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root. */
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if (buildUser) buildUser->kill();
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killSandbox(true);
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/* Terminate the recursive Nix daemon. */
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stopDaemon();
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@ -363,6 +400,60 @@ static void linkOrCopy(const Path & from, const Path & to)
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void LocalDerivationGoal::startBuilder()
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{
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if ((buildUser && buildUser->getUIDCount() != 1)
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#if __linux__
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|| settings.useCgroups
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#endif
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)
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{
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#if __linux__
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settings.requireExperimentalFeature(Xp::Cgroups);
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auto ourCgroups = getCgroups("/proc/self/cgroup");
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auto ourCgroup = ourCgroups[""];
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if (ourCgroup == "")
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throw Error("cannot determine cgroup name from /proc/self/cgroup");
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auto ourCgroupPath = canonPath("/sys/fs/cgroup/" + ourCgroup);
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if (!pathExists(ourCgroupPath))
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throw Error("expected cgroup directory '%s'", ourCgroupPath);
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static std::atomic<unsigned int> counter{0};
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cgroup = buildUser
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? fmt("%s/nix-build-uid-%d", ourCgroupPath, buildUser->getUID())
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: fmt("%s/nix-build-pid-%d-%d", ourCgroupPath, getpid(), counter++);
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debug("using cgroup '%s'", *cgroup);
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/* When using a build user, record the cgroup we used for that
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user so that if we got interrupted previously, we can kill
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any left-over cgroup first. */
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if (buildUser) {
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auto cgroupsDir = settings.nixStateDir + "/cgroups";
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createDirs(cgroupsDir);
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auto cgroupFile = fmt("%s/%d", cgroupsDir, buildUser->getUID());
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if (pathExists(cgroupFile)) {
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auto prevCgroup = readFile(cgroupFile);
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destroyCgroup(prevCgroup);
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}
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writeFile(cgroupFile, *cgroup);
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}
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#else
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throw Error("cgroups are not supported on this platform");
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#endif
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}
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/* Make sure that no other processes are executing under the
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sandbox uids. This must be done before any chownToBuilder()
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calls. */
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killSandbox(false);
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/* Right platform? */
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if (!parsedDrv->canBuildLocally(worker.store))
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throw Error("a '%s' with features {%s} is required to build '%s', but I am a '%s' with features {%s}",
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@ -376,35 +467,6 @@ void LocalDerivationGoal::startBuilder()
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additionalSandboxProfile = parsedDrv->getStringAttr("__sandboxProfile").value_or("");
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#endif
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/* Are we doing a chroot build? */
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{
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auto noChroot = parsedDrv->getBoolAttr("__noChroot");
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if (settings.sandboxMode == smEnabled) {
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if (noChroot)
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throw Error("derivation '%s' has '__noChroot' set, "
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"but that's not allowed when 'sandbox' is 'true'", worker.store.printStorePath(drvPath));
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#if __APPLE__
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if (additionalSandboxProfile != "")
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throw Error("derivation '%s' specifies a sandbox profile, "
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"but this is only allowed when 'sandbox' is 'relaxed'", worker.store.printStorePath(drvPath));
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#endif
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useChroot = true;
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}
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else if (settings.sandboxMode == smDisabled)
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useChroot = false;
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else if (settings.sandboxMode == smRelaxed)
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useChroot = derivationType.isSandboxed() && !noChroot;
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}
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auto & localStore = getLocalStore();
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if (localStore.storeDir != localStore.realStoreDir.get()) {
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#if __linux__
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useChroot = true;
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#else
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throw Error("building using a diverted store is not supported on this platform");
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#endif
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}
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/* Create a temporary directory where the build will take
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place. */
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tmpDir = createTempDir("", "nix-build-" + std::string(drvPath.name()), false, false, 0700);
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@ -580,10 +642,11 @@ void LocalDerivationGoal::startBuilder()
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printMsg(lvlChatty, format("setting up chroot environment in '%1%'") % chrootRootDir);
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if (mkdir(chrootRootDir.c_str(), 0750) == -1)
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// FIXME: make this 0700
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if (mkdir(chrootRootDir.c_str(), buildUser && buildUser->getUIDCount() != 1 ? 0755 : 0750) == -1)
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throw SysError("cannot create '%1%'", chrootRootDir);
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if (buildUser && chown(chrootRootDir.c_str(), 0, buildUser->getGID()) == -1)
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if (buildUser && chown(chrootRootDir.c_str(), buildUser->getUIDCount() != 1 ? buildUser->getUID() : 0, buildUser->getGID()) == -1)
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throw SysError("cannot change ownership of '%1%'", chrootRootDir);
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/* Create a writable /tmp in the chroot. Many builders need
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@ -597,6 +660,10 @@ void LocalDerivationGoal::startBuilder()
|
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nobody account. The latter is kind of a hack to support
|
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Samba-in-QEMU. */
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createDirs(chrootRootDir + "/etc");
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chownToBuilder(chrootRootDir + "/etc");
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|
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if (parsedDrv->useUidRange() && (!buildUser || buildUser->getUIDCount() < 65536))
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throw Error("feature 'uid-range' requires the setting '%s' to be enabled", settings.autoAllocateUids.name);
|
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/* Declare the build user's group so that programs get a consistent
|
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view of the system (e.g., "id -gn"). */
|
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@ -647,12 +714,28 @@ void LocalDerivationGoal::startBuilder()
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dirsInChroot.erase(worker.store.printStorePath(*i.second.second));
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}
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|
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#elif __APPLE__
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/* We don't really have any parent prep work to do (yet?)
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All work happens in the child, instead. */
|
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if (cgroup) {
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if (mkdir(cgroup->c_str(), 0755) != 0)
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throw SysError("creating cgroup '%s'", *cgroup);
|
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chownToBuilder(*cgroup);
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chownToBuilder(*cgroup + "/cgroup.procs");
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chownToBuilder(*cgroup + "/cgroup.threads");
|
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//chownToBuilder(*cgroup + "/cgroup.subtree_control");
|
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}
|
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|
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#else
|
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throw Error("sandboxing builds is not supported on this platform");
|
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if (parsedDrv->useUidRange())
|
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throw Error("feature 'uid-range' is not supported on this platform");
|
||||
#if __APPLE__
|
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/* We don't really have any parent prep work to do (yet?)
|
||||
All work happens in the child, instead. */
|
||||
#else
|
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throw Error("sandboxing builds is not supported on this platform");
|
||||
#endif
|
||||
#endif
|
||||
} else {
|
||||
if (parsedDrv->useUidRange())
|
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throw Error("feature 'uid-range' is only supported in sandboxed builds");
|
||||
}
|
||||
|
||||
if (needsHashRewrite() && pathExists(homeDir))
|
||||
|
|
@ -913,14 +996,16 @@ void LocalDerivationGoal::startBuilder()
|
|||
the calling user (if build users are disabled). */
|
||||
uid_t hostUid = buildUser ? buildUser->getUID() : getuid();
|
||||
uid_t hostGid = buildUser ? buildUser->getGID() : getgid();
|
||||
uid_t nrIds = buildUser ? buildUser->getUIDCount() : 1;
|
||||
|
||||
writeFile("/proc/" + std::to_string(pid) + "/uid_map",
|
||||
fmt("%d %d 1", sandboxUid(), hostUid));
|
||||
fmt("%d %d %d", sandboxUid(), hostUid, nrIds));
|
||||
|
||||
writeFile("/proc/" + std::to_string(pid) + "/setgroups", "deny");
|
||||
if (!buildUser || buildUser->getUIDCount() == 1)
|
||||
writeFile("/proc/" + std::to_string(pid) + "/setgroups", "deny");
|
||||
|
||||
writeFile("/proc/" + std::to_string(pid) + "/gid_map",
|
||||
fmt("%d %d 1", sandboxGid(), hostGid));
|
||||
fmt("%d %d %d", sandboxGid(), hostGid, nrIds));
|
||||
} else {
|
||||
debug("note: not using a user namespace");
|
||||
if (!buildUser)
|
||||
|
|
@ -947,6 +1032,10 @@ void LocalDerivationGoal::startBuilder()
|
|||
throw SysError("getting sandbox user namespace");
|
||||
}
|
||||
|
||||
/* Move the child into its own cgroup. */
|
||||
if (cgroup)
|
||||
writeFile(*cgroup + "/cgroup.procs", fmt("%d", (pid_t) pid));
|
||||
|
||||
/* Signal the builder that we've updated its user namespace. */
|
||||
writeFull(userNamespaceSync.writeSide.get(), "1");
|
||||
|
||||
|
|
@ -1779,6 +1868,13 @@ void LocalDerivationGoal::runChild()
|
|||
if (mount("none", (chrootRootDir + "/proc").c_str(), "proc", 0, 0) == -1)
|
||||
throw SysError("mounting /proc");
|
||||
|
||||
/* Mount sysfs on /sys. */
|
||||
if (buildUser && buildUser->getUIDCount() != 1) {
|
||||
createDirs(chrootRootDir + "/sys");
|
||||
if (mount("none", (chrootRootDir + "/sys").c_str(), "sysfs", 0, 0) == -1)
|
||||
throw SysError("mounting /sys");
|
||||
}
|
||||
|
||||
/* Mount a new tmpfs on /dev/shm to ensure that whatever
|
||||
the builder puts in /dev/shm is cleaned up automatically. */
|
||||
if (pathExists("/dev/shm") && mount("none", (chrootRootDir + "/dev/shm").c_str(), "tmpfs", 0,
|
||||
|
|
@ -1821,6 +1917,12 @@ void LocalDerivationGoal::runChild()
|
|||
if (unshare(CLONE_NEWNS) == -1)
|
||||
throw SysError("unsharing mount namespace");
|
||||
|
||||
/* Unshare the cgroup namespace. This means
|
||||
/proc/self/cgroup will show the child's cgroup as '/'
|
||||
rather than whatever it is in the parent. */
|
||||
if (cgroup && unshare(CLONE_NEWCGROUP) == -1)
|
||||
throw SysError("unsharing cgroup namespace");
|
||||
|
||||
/* Do the chroot(). */
|
||||
if (chdir(chrootRootDir.c_str()) == -1)
|
||||
throw SysError("cannot change directory to '%1%'", chrootRootDir);
|
||||
|
|
@ -1906,9 +2008,8 @@ void LocalDerivationGoal::runChild()
|
|||
if (setUser && buildUser) {
|
||||
/* Preserve supplementary groups of the build user, to allow
|
||||
admins to specify groups such as "kvm". */
|
||||
if (!buildUser->getSupplementaryGIDs().empty() &&
|
||||
setgroups(buildUser->getSupplementaryGIDs().size(),
|
||||
buildUser->getSupplementaryGIDs().data()) == -1)
|
||||
auto gids = buildUser->getSupplementaryGIDs();
|
||||
if (setgroups(gids.size(), gids.data()) == -1)
|
||||
throw SysError("cannot set supplementary groups of build user");
|
||||
|
||||
if (setgid(buildUser->getGID()) == -1 ||
|
||||
|
|
@ -2237,7 +2338,10 @@ DrvOutputs LocalDerivationGoal::registerOutputs()
|
|||
/* Canonicalise first. This ensures that the path we're
|
||||
rewriting doesn't contain a hard link to /etc/shadow or
|
||||
something like that. */
|
||||
canonicalisePathMetaData(actualPath, buildUser ? buildUser->getUID() : -1, inodesSeen);
|
||||
canonicalisePathMetaData(
|
||||
actualPath,
|
||||
buildUser ? std::optional(buildUser->getUIDRange()) : std::nullopt,
|
||||
inodesSeen);
|
||||
|
||||
debug("scanning for references for output '%s' in temp location '%s'", outputName, actualPath);
|
||||
|
||||
|
|
@ -2330,6 +2434,10 @@ DrvOutputs LocalDerivationGoal::registerOutputs()
|
|||
sink.s = rewriteStrings(sink.s, outputRewrites);
|
||||
StringSource source(sink.s);
|
||||
restorePath(actualPath, source);
|
||||
|
||||
/* FIXME: set proper permissions in restorePath() so
|
||||
we don't have to do another traversal. */
|
||||
canonicalisePathMetaData(actualPath, {}, inodesSeen);
|
||||
}
|
||||
};
|
||||
|
||||
|
|
@ -2492,7 +2600,7 @@ DrvOutputs LocalDerivationGoal::registerOutputs()
|
|||
|
||||
/* FIXME: set proper permissions in restorePath() so
|
||||
we don't have to do another traversal. */
|
||||
canonicalisePathMetaData(actualPath, -1, inodesSeen);
|
||||
canonicalisePathMetaData(actualPath, {}, inodesSeen);
|
||||
|
||||
/* Calculate where we'll move the output files. In the checking case we
|
||||
will leave leave them where they are, for now, rather than move to
|
||||
|
|
|
|||
|
|
@ -15,6 +15,9 @@ struct LocalDerivationGoal : public DerivationGoal
|
|||
/* The process ID of the builder. */
|
||||
Pid pid;
|
||||
|
||||
/* The cgroup of the builder, if any. */
|
||||
std::optional<Path> cgroup;
|
||||
|
||||
/* The temporary directory. */
|
||||
Path tmpDir;
|
||||
|
||||
|
|
@ -92,8 +95,8 @@ struct LocalDerivationGoal : public DerivationGoal
|
|||
result. */
|
||||
std::map<Path, ValidPathInfo> prevInfos;
|
||||
|
||||
uid_t sandboxUid() { return usingUserNamespace ? 1000 : buildUser->getUID(); }
|
||||
gid_t sandboxGid() { return usingUserNamespace ? 100 : buildUser->getGID(); }
|
||||
uid_t sandboxUid() { return usingUserNamespace ? (!buildUser || buildUser->getUIDCount() == 1 ? 1000 : 0) : buildUser->getUID(); }
|
||||
gid_t sandboxGid() { return usingUserNamespace ? (!buildUser || buildUser->getUIDCount() == 1 ? 100 : 0) : buildUser->getGID(); }
|
||||
|
||||
const static Path homeDir;
|
||||
|
||||
|
|
@ -197,6 +200,10 @@ struct LocalDerivationGoal : public DerivationGoal
|
|||
/* Forcibly kill the child process, if any. */
|
||||
void killChild() override;
|
||||
|
||||
/* Kill any processes running under the build user UID or in the
|
||||
cgroup of the build. */
|
||||
void killSandbox(bool getStats);
|
||||
|
||||
/* Create alternative path calculated from but distinct from the
|
||||
input, so we can avoid overwriting outputs (or other store paths)
|
||||
that already exist. */
|
||||
|
|
|
|||
131
src/libstore/cgroup.cc
Normal file
131
src/libstore/cgroup.cc
Normal file
|
|
@ -0,0 +1,131 @@
|
|||
#if __linux__
|
||||
|
||||
#include "cgroup.hh"
|
||||
#include "util.hh"
|
||||
|
||||
#include <chrono>
|
||||
#include <cmath>
|
||||
#include <regex>
|
||||
#include <unordered_set>
|
||||
#include <thread>
|
||||
|
||||
#include <dirent.h>
|
||||
|
||||
namespace nix {
|
||||
|
||||
// FIXME: obsolete, check for cgroup2
|
||||
std::map<std::string, std::string> getCgroups(const Path & cgroupFile)
|
||||
{
|
||||
std::map<std::string, std::string> cgroups;
|
||||
|
||||
for (auto & line : tokenizeString<std::vector<std::string>>(readFile(cgroupFile), "\n")) {
|
||||
static std::regex regex("([0-9]+):([^:]*):(.*)");
|
||||
std::smatch match;
|
||||
if (!std::regex_match(line, match, regex))
|
||||
throw Error("invalid line '%s' in '%s'", line, cgroupFile);
|
||||
|
||||
std::string name = hasPrefix(std::string(match[2]), "name=") ? std::string(match[2], 5) : match[2];
|
||||
cgroups.insert_or_assign(name, match[3]);
|
||||
}
|
||||
|
||||
return cgroups;
|
||||
}
|
||||
|
||||
static CgroupStats destroyCgroup(const Path & cgroup, bool returnStats)
|
||||
{
|
||||
if (!pathExists(cgroup)) return {};
|
||||
|
||||
auto procsFile = cgroup + "/cgroup.procs";
|
||||
|
||||
if (!pathExists(procsFile))
|
||||
throw Error("'%s' is not a cgroup", cgroup);
|
||||
|
||||
/* Use the fast way to kill every process in a cgroup, if
|
||||
available. */
|
||||
auto killFile = cgroup + "/cgroup.kill";
|
||||
if (pathExists(killFile))
|
||||
writeFile(killFile, "1");
|
||||
|
||||
/* Otherwise, manually kill every process in the subcgroups and
|
||||
this cgroup. */
|
||||
for (auto & entry : readDirectory(cgroup)) {
|
||||
if (entry.type != DT_DIR) continue;
|
||||
destroyCgroup(cgroup + "/" + entry.name, false);
|
||||
}
|
||||
|
||||
int round = 1;
|
||||
|
||||
std::unordered_set<pid_t> pidsShown;
|
||||
|
||||
while (true) {
|
||||
auto pids = tokenizeString<std::vector<std::string>>(readFile(procsFile));
|
||||
|
||||
if (pids.empty()) break;
|
||||
|
||||
if (round > 20)
|
||||
throw Error("cannot kill cgroup '%s'", cgroup);
|
||||
|
||||
for (auto & pid_s : pids) {
|
||||
pid_t pid;
|
||||
if (auto o = string2Int<pid_t>(pid_s))
|
||||
pid = *o;
|
||||
else
|
||||
throw Error("invalid pid '%s'", pid);
|
||||
if (pidsShown.insert(pid).second) {
|
||||
try {
|
||||
auto cmdline = readFile(fmt("/proc/%d/cmdline", pid));
|
||||
using namespace std::string_literals;
|
||||
warn("killing stray builder process %d (%s)...",
|
||||
pid, trim(replaceStrings(cmdline, "\0"s, " ")));
|
||||
} catch (SysError &) {
|
||||
}
|
||||
}
|
||||
// FIXME: pid wraparound
|
||||
if (kill(pid, SIGKILL) == -1 && errno != ESRCH)
|
||||
throw SysError("killing member %d of cgroup '%s'", pid, cgroup);
|
||||
}
|
||||
|
||||
auto sleep = std::chrono::milliseconds((int) std::pow(2.0, std::min(round, 10)));
|
||||
if (sleep.count() > 100)
|
||||
printError("waiting for %d ms for cgroup '%s' to become empty", sleep.count(), cgroup);
|
||||
std::this_thread::sleep_for(sleep);
|
||||
round++;
|
||||
}
|
||||
|
||||
CgroupStats stats;
|
||||
|
||||
if (returnStats) {
|
||||
auto cpustatPath = cgroup + "/cpu.stat";
|
||||
|
||||
if (pathExists(cpustatPath)) {
|
||||
for (auto & line : tokenizeString<std::vector<std::string>>(readFile(cpustatPath), "\n")) {
|
||||
std::string_view userPrefix = "user_usec ";
|
||||
if (hasPrefix(line, userPrefix)) {
|
||||
auto n = string2Int<uint64_t>(line.substr(userPrefix.size()));
|
||||
if (n) stats.cpuUser = std::chrono::microseconds(*n);
|
||||
}
|
||||
|
||||
std::string_view systemPrefix = "system_usec ";
|
||||
if (hasPrefix(line, systemPrefix)) {
|
||||
auto n = string2Int<uint64_t>(line.substr(systemPrefix.size()));
|
||||
if (n) stats.cpuSystem = std::chrono::microseconds(*n);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
if (rmdir(cgroup.c_str()) == -1)
|
||||
throw SysError("deleting cgroup '%s'", cgroup);
|
||||
|
||||
return stats;
|
||||
}
|
||||
|
||||
CgroupStats destroyCgroup(const Path & cgroup)
|
||||
{
|
||||
return destroyCgroup(cgroup, true);
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
#endif
|
||||
27
src/libstore/cgroup.hh
Normal file
27
src/libstore/cgroup.hh
Normal file
|
|
@ -0,0 +1,27 @@
|
|||
#pragma once
|
||||
|
||||
#if __linux__
|
||||
|
||||
#include <chrono>
|
||||
#include <optional>
|
||||
|
||||
#include "types.hh"
|
||||
|
||||
namespace nix {
|
||||
|
||||
std::map<std::string, std::string> getCgroups(const Path & cgroupFile);
|
||||
|
||||
struct CgroupStats
|
||||
{
|
||||
std::optional<std::chrono::microseconds> cpuUser, cpuSystem;
|
||||
};
|
||||
|
||||
/* Destroy the cgroup denoted by 'path'. The postcondition is that
|
||||
'path' does not exist, and thus any processes in the cgroup have
|
||||
been killed. Also return statistics from the cgroup just before
|
||||
destruction. */
|
||||
CgroupStats destroyCgroup(const Path & cgroup);
|
||||
|
||||
}
|
||||
|
||||
#endif
|
||||
|
|
@ -130,6 +130,10 @@ StringSet Settings::getDefaultSystemFeatures()
|
|||
actually require anything special on the machines. */
|
||||
StringSet features{"nixos-test", "benchmark", "big-parallel"};
|
||||
|
||||
#if __linux__
|
||||
features.insert("uid-range");
|
||||
#endif
|
||||
|
||||
#if __linux__
|
||||
if (access("/dev/kvm", R_OK | W_OK) == 0)
|
||||
features.insert("kvm");
|
||||
|
|
|
|||
|
|
@ -46,6 +46,14 @@ struct PluginFilesSetting : public BaseSetting<Paths>
|
|||
void set(const std::string & str, bool append = false) override;
|
||||
};
|
||||
|
||||
const uint32_t maxIdsPerBuild =
|
||||
#if __linux__
|
||||
1 << 16
|
||||
#else
|
||||
1
|
||||
#endif
|
||||
;
|
||||
|
||||
class Settings : public Config {
|
||||
|
||||
unsigned int getDefaultCores();
|
||||
|
|
@ -275,6 +283,38 @@ public:
|
|||
multi-user settings with untrusted users.
|
||||
)"};
|
||||
|
||||
Setting<bool> autoAllocateUids{this, false, "auto-allocate-uids",
|
||||
"Whether to allocate UIDs for builders automatically."};
|
||||
|
||||
Setting<uint32_t> startId{this,
|
||||
#if __linux__
|
||||
0x34000000,
|
||||
#else
|
||||
56930,
|
||||
#endif
|
||||
"start-id",
|
||||
"The first UID and GID to use for dynamic ID allocation."};
|
||||
|
||||
Setting<uint32_t> uidCount{this,
|
||||
#if __linux__
|
||||
maxIdsPerBuild * 128,
|
||||
#else
|
||||
128,
|
||||
#endif
|
||||
"id-count",
|
||||
"The number of UIDs/GIDs to use for dynamic ID allocation."};
|
||||
|
||||
#if __linux__
|
||||
Setting<bool> useCgroups{
|
||||
this, false, "use-cgroups",
|
||||
R"(
|
||||
Whether to execute builds inside cgroups. Cgroups are
|
||||
enabled automatically for derivations that require the
|
||||
`uid-range` system feature.
|
||||
)"
|
||||
};
|
||||
#endif
|
||||
|
||||
Setting<bool> impersonateLinux26{this, false, "impersonate-linux-26",
|
||||
"Whether to impersonate a Linux 2.6 machine on newer kernels.",
|
||||
{"build-impersonate-linux-26"}};
|
||||
|
|
@ -563,10 +603,10 @@ public:
|
|||
cache) must have a signature by a trusted key. A trusted key is one
|
||||
listed in `trusted-public-keys`, or a public key counterpart to a
|
||||
private key stored in a file listed in `secret-key-files`.
|
||||
|
||||
|
||||
Set to `false` to disable signature checking and trust all
|
||||
non-content-addressed paths unconditionally.
|
||||
|
||||
|
||||
(Content-addressed paths are inherently trustworthy and thus
|
||||
unaffected by this configuration option.)
|
||||
)"};
|
||||
|
|
|
|||
|
|
@ -583,7 +583,10 @@ void canonicaliseTimestampAndPermissions(const Path & path)
|
|||
}
|
||||
|
||||
|
||||
static void canonicalisePathMetaData_(const Path & path, uid_t fromUid, InodesSeen & inodesSeen)
|
||||
static void canonicalisePathMetaData_(
|
||||
const Path & path,
|
||||
std::optional<std::pair<uid_t, uid_t>> uidRange,
|
||||
InodesSeen & inodesSeen)
|
||||
{
|
||||
checkInterrupt();
|
||||
|
||||
|
|
@ -630,7 +633,7 @@ static void canonicalisePathMetaData_(const Path & path, uid_t fromUid, InodesSe
|
|||
However, ignore files that we chown'ed ourselves previously to
|
||||
ensure that we don't fail on hard links within the same build
|
||||
(i.e. "touch $out/foo; ln $out/foo $out/bar"). */
|
||||
if (fromUid != (uid_t) -1 && st.st_uid != fromUid) {
|
||||
if (uidRange && (st.st_uid < uidRange->first || st.st_uid > uidRange->second)) {
|
||||
if (S_ISDIR(st.st_mode) || !inodesSeen.count(Inode(st.st_dev, st.st_ino)))
|
||||
throw BuildError("invalid ownership on file '%1%'", path);
|
||||
mode_t mode = st.st_mode & ~S_IFMT;
|
||||
|
|
@ -663,14 +666,17 @@ static void canonicalisePathMetaData_(const Path & path, uid_t fromUid, InodesSe
|
|||
if (S_ISDIR(st.st_mode)) {
|
||||
DirEntries entries = readDirectory(path);
|
||||
for (auto & i : entries)
|
||||
canonicalisePathMetaData_(path + "/" + i.name, fromUid, inodesSeen);
|
||||
canonicalisePathMetaData_(path + "/" + i.name, uidRange, inodesSeen);
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
void canonicalisePathMetaData(const Path & path, uid_t fromUid, InodesSeen & inodesSeen)
|
||||
void canonicalisePathMetaData(
|
||||
const Path & path,
|
||||
std::optional<std::pair<uid_t, uid_t>> uidRange,
|
||||
InodesSeen & inodesSeen)
|
||||
{
|
||||
canonicalisePathMetaData_(path, fromUid, inodesSeen);
|
||||
canonicalisePathMetaData_(path, uidRange, inodesSeen);
|
||||
|
||||
/* On platforms that don't have lchown(), the top-level path can't
|
||||
be a symlink, since we can't change its ownership. */
|
||||
|
|
@ -683,10 +689,11 @@ void canonicalisePathMetaData(const Path & path, uid_t fromUid, InodesSeen & ino
|
|||
}
|
||||
|
||||
|
||||
void canonicalisePathMetaData(const Path & path, uid_t fromUid)
|
||||
void canonicalisePathMetaData(const Path & path,
|
||||
std::optional<std::pair<uid_t, uid_t>> uidRange)
|
||||
{
|
||||
InodesSeen inodesSeen;
|
||||
canonicalisePathMetaData(path, fromUid, inodesSeen);
|
||||
canonicalisePathMetaData(path, uidRange, inodesSeen);
|
||||
}
|
||||
|
||||
|
||||
|
|
@ -1331,7 +1338,7 @@ void LocalStore::addToStore(const ValidPathInfo & info, Source & source,
|
|||
|
||||
autoGC();
|
||||
|
||||
canonicalisePathMetaData(realPath, -1);
|
||||
canonicalisePathMetaData(realPath, {});
|
||||
|
||||
optimisePath(realPath, repair); // FIXME: combine with hashPath()
|
||||
|
||||
|
|
@ -1444,7 +1451,7 @@ StorePath LocalStore::addToStoreFromDump(Source & source0, std::string_view name
|
|||
narHash = narSink.finish();
|
||||
}
|
||||
|
||||
canonicalisePathMetaData(realPath, -1); // FIXME: merge into restorePath
|
||||
canonicalisePathMetaData(realPath, {}); // FIXME: merge into restorePath
|
||||
|
||||
optimisePath(realPath, repair);
|
||||
|
||||
|
|
@ -1486,7 +1493,7 @@ StorePath LocalStore::addTextToStore(
|
|||
|
||||
writeFile(realPath, s);
|
||||
|
||||
canonicalisePathMetaData(realPath, -1);
|
||||
canonicalisePathMetaData(realPath, {});
|
||||
|
||||
StringSink sink;
|
||||
dumpString(s, sink);
|
||||
|
|
|
|||
|
|
@ -310,9 +310,18 @@ typedef std::set<Inode> InodesSeen;
|
|||
- the permissions are set of 444 or 555 (i.e., read-only with or
|
||||
without execute permission; setuid bits etc. are cleared)
|
||||
- the owner and group are set to the Nix user and group, if we're
|
||||
running as root. */
|
||||
void canonicalisePathMetaData(const Path & path, uid_t fromUid, InodesSeen & inodesSeen);
|
||||
void canonicalisePathMetaData(const Path & path, uid_t fromUid);
|
||||
running as root.
|
||||
If uidRange is not empty, this function will throw an error if it
|
||||
encounters files owned by a user outside of the closed interval
|
||||
[uidRange->first, uidRange->second].
|
||||
*/
|
||||
void canonicalisePathMetaData(
|
||||
const Path & path,
|
||||
std::optional<std::pair<uid_t, uid_t>> uidRange,
|
||||
InodesSeen & inodesSeen);
|
||||
void canonicalisePathMetaData(
|
||||
const Path & path,
|
||||
std::optional<std::pair<uid_t, uid_t>> uidRange);
|
||||
|
||||
void canonicaliseTimestampAndPermissions(const Path & path);
|
||||
|
||||
|
|
|
|||
|
|
@ -2,105 +2,197 @@
|
|||
#include "globals.hh"
|
||||
#include "pathlocks.hh"
|
||||
|
||||
#include <grp.h>
|
||||
#include <pwd.h>
|
||||
|
||||
#include <fcntl.h>
|
||||
#include <unistd.h>
|
||||
#include <grp.h>
|
||||
|
||||
namespace nix {
|
||||
|
||||
UserLock::UserLock()
|
||||
struct SimpleUserLock : UserLock
|
||||
{
|
||||
assert(settings.buildUsersGroup != "");
|
||||
createDirs(settings.nixStateDir + "/userpool");
|
||||
}
|
||||
AutoCloseFD fdUserLock;
|
||||
uid_t uid;
|
||||
gid_t gid;
|
||||
std::vector<gid_t> supplementaryGIDs;
|
||||
|
||||
bool UserLock::findFreeUser() {
|
||||
if (enabled()) return true;
|
||||
uid_t getUID() override { assert(uid); return uid; }
|
||||
uid_t getUIDCount() override { return 1; }
|
||||
gid_t getGID() override { assert(gid); return gid; }
|
||||
|
||||
/* Get the members of the build-users-group. */
|
||||
struct group * gr = getgrnam(settings.buildUsersGroup.get().c_str());
|
||||
if (!gr)
|
||||
throw Error("the group '%1%' specified in 'build-users-group' does not exist",
|
||||
settings.buildUsersGroup);
|
||||
gid = gr->gr_gid;
|
||||
std::vector<gid_t> getSupplementaryGIDs() override { return supplementaryGIDs; }
|
||||
|
||||
/* Copy the result of getgrnam. */
|
||||
Strings users;
|
||||
for (char * * p = gr->gr_mem; *p; ++p) {
|
||||
debug("found build user '%1%'", *p);
|
||||
users.push_back(*p);
|
||||
}
|
||||
static std::unique_ptr<UserLock> acquire()
|
||||
{
|
||||
assert(settings.buildUsersGroup != "");
|
||||
createDirs(settings.nixStateDir + "/userpool");
|
||||
|
||||
if (users.empty())
|
||||
throw Error("the build users group '%1%' has no members",
|
||||
settings.buildUsersGroup);
|
||||
/* Get the members of the build-users-group. */
|
||||
struct group * gr = getgrnam(settings.buildUsersGroup.get().c_str());
|
||||
if (!gr)
|
||||
throw Error("the group '%s' specified in 'build-users-group' does not exist", settings.buildUsersGroup);
|
||||
|
||||
/* Find a user account that isn't currently in use for another
|
||||
build. */
|
||||
for (auto & i : users) {
|
||||
debug("trying user '%1%'", i);
|
||||
|
||||
struct passwd * pw = getpwnam(i.c_str());
|
||||
if (!pw)
|
||||
throw Error("the user '%1%' in the group '%2%' does not exist",
|
||||
i, settings.buildUsersGroup);
|
||||
|
||||
|
||||
fnUserLock = (format("%1%/userpool/%2%") % settings.nixStateDir % pw->pw_uid).str();
|
||||
|
||||
AutoCloseFD fd = open(fnUserLock.c_str(), O_RDWR | O_CREAT | O_CLOEXEC, 0600);
|
||||
if (!fd)
|
||||
throw SysError("opening user lock '%1%'", fnUserLock);
|
||||
|
||||
if (lockFile(fd.get(), ltWrite, false)) {
|
||||
fdUserLock = std::move(fd);
|
||||
user = i;
|
||||
uid = pw->pw_uid;
|
||||
|
||||
/* Sanity check... */
|
||||
if (uid == getuid() || uid == geteuid())
|
||||
throw Error("the Nix user should not be a member of '%1%'",
|
||||
settings.buildUsersGroup);
|
||||
|
||||
#if __linux__
|
||||
/* Get the list of supplementary groups of this build user. This
|
||||
is usually either empty or contains a group such as "kvm". */
|
||||
int ngroups = 32; // arbitrary initial guess
|
||||
supplementaryGIDs.resize(ngroups);
|
||||
|
||||
int err = getgrouplist(pw->pw_name, pw->pw_gid, supplementaryGIDs.data(),
|
||||
&ngroups);
|
||||
|
||||
// Our initial size of 32 wasn't sufficient, the correct size has
|
||||
// been stored in ngroups, so we try again.
|
||||
if (err == -1) {
|
||||
supplementaryGIDs.resize(ngroups);
|
||||
err = getgrouplist(pw->pw_name, pw->pw_gid, supplementaryGIDs.data(),
|
||||
&ngroups);
|
||||
}
|
||||
|
||||
// If it failed once more, then something must be broken.
|
||||
if (err == -1)
|
||||
throw Error("failed to get list of supplementary groups for '%1%'",
|
||||
pw->pw_name);
|
||||
|
||||
// Finally, trim back the GID list to its real size
|
||||
supplementaryGIDs.resize(ngroups);
|
||||
#endif
|
||||
|
||||
isEnabled = true;
|
||||
return true;
|
||||
/* Copy the result of getgrnam. */
|
||||
Strings users;
|
||||
for (char * * p = gr->gr_mem; *p; ++p) {
|
||||
debug("found build user '%s'", *p);
|
||||
users.push_back(*p);
|
||||
}
|
||||
|
||||
if (users.empty())
|
||||
throw Error("the build users group '%s' has no members", settings.buildUsersGroup);
|
||||
|
||||
/* Find a user account that isn't currently in use for another
|
||||
build. */
|
||||
for (auto & i : users) {
|
||||
debug("trying user '%s'", i);
|
||||
|
||||
struct passwd * pw = getpwnam(i.c_str());
|
||||
if (!pw)
|
||||
throw Error("the user '%s' in the group '%s' does not exist", i, settings.buildUsersGroup);
|
||||
|
||||
auto fnUserLock = fmt("%s/userpool/%s", settings.nixStateDir,pw->pw_uid);
|
||||
|
||||
AutoCloseFD fd = open(fnUserLock.c_str(), O_RDWR | O_CREAT | O_CLOEXEC, 0600);
|
||||
if (!fd)
|
||||
throw SysError("opening user lock '%s'", fnUserLock);
|
||||
|
||||
if (lockFile(fd.get(), ltWrite, false)) {
|
||||
auto lock = std::make_unique<SimpleUserLock>();
|
||||
|
||||
lock->fdUserLock = std::move(fd);
|
||||
lock->uid = pw->pw_uid;
|
||||
lock->gid = gr->gr_gid;
|
||||
|
||||
/* Sanity check... */
|
||||
if (lock->uid == getuid() || lock->uid == geteuid())
|
||||
throw Error("the Nix user should not be a member of '%s'", settings.buildUsersGroup);
|
||||
|
||||
#if __linux__
|
||||
/* Get the list of supplementary groups of this build
|
||||
user. This is usually either empty or contains a
|
||||
group such as "kvm". */
|
||||
int ngroups = 32; // arbitrary initial guess
|
||||
std::vector<gid_t> gids;
|
||||
gids.resize(ngroups);
|
||||
|
||||
int err = getgrouplist(
|
||||
pw->pw_name, pw->pw_gid,
|
||||
gids.data(),
|
||||
&ngroups);
|
||||
|
||||
/* Our initial size of 32 wasn't sufficient, the
|
||||
correct size has been stored in ngroups, so we try
|
||||
again. */
|
||||
if (err == -1) {
|
||||
gids.resize(ngroups);
|
||||
err = getgrouplist(
|
||||
pw->pw_name, pw->pw_gid,
|
||||
gids.data(),
|
||||
&ngroups);
|
||||
}
|
||||
|
||||
// If it failed once more, then something must be broken.
|
||||
if (err == -1)
|
||||
throw Error("failed to get list of supplementary groups for '%s'", pw->pw_name);
|
||||
|
||||
// Finally, trim back the GID list to its real size.
|
||||
for (auto i = 0; i < ngroups; i++)
|
||||
if (gids[i] != lock->gid)
|
||||
lock->supplementaryGIDs.push_back(gids[i]);
|
||||
#endif
|
||||
|
||||
return lock;
|
||||
}
|
||||
}
|
||||
|
||||
return nullptr;
|
||||
}
|
||||
};
|
||||
|
||||
return false;
|
||||
}
|
||||
|
||||
void UserLock::kill()
|
||||
struct AutoUserLock : UserLock
|
||||
{
|
||||
killUser(uid);
|
||||
AutoCloseFD fdUserLock;
|
||||
uid_t firstUid = 0;
|
||||
gid_t firstGid = 0;
|
||||
uid_t nrIds = 1;
|
||||
|
||||
uid_t getUID() override { assert(firstUid); return firstUid; }
|
||||
|
||||
gid_t getUIDCount() override { return nrIds; }
|
||||
|
||||
gid_t getGID() override { assert(firstGid); return firstGid; }
|
||||
|
||||
std::vector<gid_t> getSupplementaryGIDs() override { return {}; }
|
||||
|
||||
static std::unique_ptr<UserLock> acquire(uid_t nrIds, bool useChroot)
|
||||
{
|
||||
settings.requireExperimentalFeature(Xp::AutoAllocateUids);
|
||||
assert(settings.startId > 0);
|
||||
assert(settings.uidCount % maxIdsPerBuild == 0);
|
||||
assert((uint64_t) settings.startId + (uint64_t) settings.uidCount <= std::numeric_limits<uid_t>::max());
|
||||
assert(nrIds <= maxIdsPerBuild);
|
||||
|
||||
createDirs(settings.nixStateDir + "/userpool2");
|
||||
|
||||
size_t nrSlots = settings.uidCount / maxIdsPerBuild;
|
||||
|
||||
for (size_t i = 0; i < nrSlots; i++) {
|
||||
debug("trying user slot '%d'", i);
|
||||
|
||||
createDirs(settings.nixStateDir + "/userpool2");
|
||||
|
||||
auto fnUserLock = fmt("%s/userpool2/slot-%d", settings.nixStateDir, i);
|
||||
|
||||
AutoCloseFD fd = open(fnUserLock.c_str(), O_RDWR | O_CREAT | O_CLOEXEC, 0600);
|
||||
if (!fd)
|
||||
throw SysError("opening user lock '%s'", fnUserLock);
|
||||
|
||||
if (lockFile(fd.get(), ltWrite, false)) {
|
||||
|
||||
auto firstUid = settings.startId + i * maxIdsPerBuild;
|
||||
|
||||
auto pw = getpwuid(firstUid);
|
||||
if (pw)
|
||||
throw Error("auto-allocated UID %d clashes with existing user account '%s'", firstUid, pw->pw_name);
|
||||
|
||||
auto lock = std::make_unique<AutoUserLock>();
|
||||
lock->fdUserLock = std::move(fd);
|
||||
lock->firstUid = firstUid;
|
||||
if (useChroot)
|
||||
lock->firstGid = firstUid;
|
||||
else {
|
||||
struct group * gr = getgrnam(settings.buildUsersGroup.get().c_str());
|
||||
if (!gr)
|
||||
throw Error("the group '%s' specified in 'build-users-group' does not exist", settings.buildUsersGroup);
|
||||
lock->firstGid = gr->gr_gid;
|
||||
}
|
||||
lock->nrIds = nrIds;
|
||||
return lock;
|
||||
}
|
||||
}
|
||||
|
||||
return nullptr;
|
||||
}
|
||||
};
|
||||
|
||||
std::unique_ptr<UserLock> acquireUserLock(uid_t nrIds, bool useChroot)
|
||||
{
|
||||
if (settings.autoAllocateUids)
|
||||
return AutoUserLock::acquire(nrIds, useChroot);
|
||||
else
|
||||
return SimpleUserLock::acquire();
|
||||
}
|
||||
|
||||
bool useBuildUsers()
|
||||
{
|
||||
#if __linux__
|
||||
static bool b = (settings.buildUsersGroup != "" || settings.startId.get() != 0) && getuid() == 0;
|
||||
return b;
|
||||
#elif __APPLE__
|
||||
static bool b = settings.buildUsersGroup != "" && getuid() == 0;
|
||||
return b;
|
||||
#else
|
||||
return false;
|
||||
#endif
|
||||
}
|
||||
|
||||
}
|
||||
|
|
|
|||
|
|
@ -1,37 +1,38 @@
|
|||
#pragma once
|
||||
|
||||
#include "sync.hh"
|
||||
#include "types.hh"
|
||||
#include "util.hh"
|
||||
|
||||
#include <optional>
|
||||
|
||||
#include <sys/types.h>
|
||||
|
||||
namespace nix {
|
||||
|
||||
class UserLock
|
||||
struct UserLock
|
||||
{
|
||||
private:
|
||||
Path fnUserLock;
|
||||
AutoCloseFD fdUserLock;
|
||||
virtual ~UserLock() { }
|
||||
|
||||
bool isEnabled = false;
|
||||
std::string user;
|
||||
uid_t uid = 0;
|
||||
gid_t gid = 0;
|
||||
std::vector<gid_t> supplementaryGIDs;
|
||||
/* Get the first and last UID. */
|
||||
std::pair<uid_t, uid_t> getUIDRange()
|
||||
{
|
||||
auto first = getUID();
|
||||
return {first, first + getUIDCount() - 1};
|
||||
}
|
||||
|
||||
public:
|
||||
UserLock();
|
||||
/* Get the first UID. */
|
||||
virtual uid_t getUID() = 0;
|
||||
|
||||
void kill();
|
||||
virtual uid_t getUIDCount() = 0;
|
||||
|
||||
std::string getUser() { return user; }
|
||||
uid_t getUID() { assert(uid); return uid; }
|
||||
uid_t getGID() { assert(gid); return gid; }
|
||||
std::vector<gid_t> getSupplementaryGIDs() { return supplementaryGIDs; }
|
||||
|
||||
bool findFreeUser();
|
||||
|
||||
bool enabled() { return isEnabled; }
|
||||
virtual gid_t getGID() = 0;
|
||||
|
||||
virtual std::vector<gid_t> getSupplementaryGIDs() = 0;
|
||||
};
|
||||
|
||||
/* Acquire a user lock for a UID range of size `nrIds`. Note that this
|
||||
may return nullptr if no user is available. */
|
||||
std::unique_ptr<UserLock> acquireUserLock(uid_t nrIds, bool useChroot);
|
||||
|
||||
bool useBuildUsers();
|
||||
|
||||
}
|
||||
|
|
|
|||
|
|
@ -89,6 +89,7 @@ std::optional<Strings> ParsedDerivation::getStringsAttr(const std::string & name
|
|||
|
||||
StringSet ParsedDerivation::getRequiredSystemFeatures() const
|
||||
{
|
||||
// FIXME: cache this?
|
||||
StringSet res;
|
||||
for (auto & i : getStringsAttr("requiredSystemFeatures").value_or(Strings()))
|
||||
res.insert(i);
|
||||
|
|
@ -124,6 +125,11 @@ bool ParsedDerivation::substitutesAllowed() const
|
|||
return getBoolAttr("allowSubstitutes", true);
|
||||
}
|
||||
|
||||
bool ParsedDerivation::useUidRange() const
|
||||
{
|
||||
return getRequiredSystemFeatures().count("uid-range");
|
||||
}
|
||||
|
||||
static std::regex shVarName("[A-Za-z_][A-Za-z0-9_]*");
|
||||
|
||||
std::optional<nlohmann::json> ParsedDerivation::prepareStructuredAttrs(Store & store, const StorePathSet & inputPaths)
|
||||
|
|
|
|||
|
|
@ -38,6 +38,8 @@ public:
|
|||
|
||||
bool substitutesAllowed() const;
|
||||
|
||||
bool useUidRange() const;
|
||||
|
||||
std::optional<nlohmann::json> prepareStructuredAttrs(Store & store, const StorePathSet & inputPaths);
|
||||
};
|
||||
|
||||
|
|
|
|||
|
|
@ -14,6 +14,8 @@ std::map<ExperimentalFeature, std::string> stringifiedXpFeatures = {
|
|||
{ Xp::NoUrlLiterals, "no-url-literals" },
|
||||
{ Xp::FetchClosure, "fetch-closure" },
|
||||
{ Xp::ReplFlake, "repl-flake" },
|
||||
{ Xp::AutoAllocateUids, "auto-allocate-uids" },
|
||||
{ Xp::Cgroups, "cgroups" },
|
||||
};
|
||||
|
||||
const std::optional<ExperimentalFeature> parseExperimentalFeature(const std::string_view & name)
|
||||
|
|
|
|||
|
|
@ -23,6 +23,8 @@ enum struct ExperimentalFeature
|
|||
NoUrlLiterals,
|
||||
FetchClosure,
|
||||
ReplFlake,
|
||||
AutoAllocateUids,
|
||||
Cgroups,
|
||||
};
|
||||
|
||||
/**
|
||||
|
|
|
|||
|
|
@ -1,5 +1,6 @@
|
|||
#include <sys/time.h>
|
||||
#include <filesystem>
|
||||
#include <atomic>
|
||||
|
||||
#include "finally.hh"
|
||||
#include "util.hh"
|
||||
|
|
@ -10,7 +11,7 @@ namespace fs = std::filesystem;
|
|||
namespace nix {
|
||||
|
||||
static Path tempName(Path tmpRoot, const Path & prefix, bool includePid,
|
||||
int & counter)
|
||||
std::atomic<unsigned int> & counter)
|
||||
{
|
||||
tmpRoot = canonPath(tmpRoot.empty() ? getEnv("TMPDIR").value_or("/tmp") : tmpRoot, true);
|
||||
if (includePid)
|
||||
|
|
@ -22,9 +23,9 @@ static Path tempName(Path tmpRoot, const Path & prefix, bool includePid,
|
|||
Path createTempDir(const Path & tmpRoot, const Path & prefix,
|
||||
bool includePid, bool useGlobalCounter, mode_t mode)
|
||||
{
|
||||
static int globalCounter = 0;
|
||||
int localCounter = 0;
|
||||
int & counter(useGlobalCounter ? globalCounter : localCounter);
|
||||
static std::atomic<unsigned int> globalCounter = 0;
|
||||
std::atomic<unsigned int> localCounter = 0;
|
||||
auto & counter(useGlobalCounter ? globalCounter : localCounter);
|
||||
|
||||
while (1) {
|
||||
checkInterrupt();
|
||||
|
|
|
|||
|
|
@ -516,7 +516,7 @@ static void registerValidity(bool reregister, bool hashGiven, bool canonicalise)
|
|||
if (!store->isValidPath(info->path) || reregister) {
|
||||
/* !!! races */
|
||||
if (canonicalise)
|
||||
canonicalisePathMetaData(store->printStorePath(info->path), -1);
|
||||
canonicalisePathMetaData(store->printStorePath(info->path), {});
|
||||
if (!hashGiven) {
|
||||
HashResult hash = hashPath(htSHA256, store->printStorePath(info->path));
|
||||
info->narHash = hash.first;
|
||||
|
|
|
|||
|
|
@ -30,6 +30,10 @@ nlohmann::json builtPathsWithResultToJSON(const std::vector<BuiltPathWithResult>
|
|||
if (b.result) {
|
||||
j["startTime"] = b.result->startTime;
|
||||
j["stopTime"] = b.result->stopTime;
|
||||
if (b.result->cpuUser)
|
||||
j["cpuUser"] = ((double) b.result->cpuUser->count()) / 1000000;
|
||||
if (b.result->cpuSystem)
|
||||
j["cpuSystem"] = ((double) b.result->cpuSystem->count()) / 1000000;
|
||||
}
|
||||
res.push_back(j);
|
||||
}, b.path.raw());
|
||||
|
|
|
|||
68
tests/containers.nix
Normal file
68
tests/containers.nix
Normal file
|
|
@ -0,0 +1,68 @@
|
|||
# Test whether we can run a NixOS container inside a Nix build using systemd-nspawn.
|
||||
{ nixpkgs, system, overlay }:
|
||||
|
||||
with import (nixpkgs + "/nixos/lib/testing-python.nix") {
|
||||
inherit system;
|
||||
extraConfigurations = [ { nixpkgs.overlays = [ overlay ]; } ];
|
||||
};
|
||||
|
||||
makeTest ({
|
||||
name = "containers";
|
||||
|
||||
nodes =
|
||||
{
|
||||
host =
|
||||
{ config, lib, pkgs, nodes, ... }:
|
||||
{ virtualisation.writableStore = true;
|
||||
virtualisation.diskSize = 2048;
|
||||
virtualisation.additionalPaths =
|
||||
[ pkgs.stdenv
|
||||
(import ./systemd-nspawn.nix { inherit nixpkgs; }).toplevel
|
||||
];
|
||||
virtualisation.memorySize = 4096;
|
||||
nix.binaryCaches = lib.mkForce [ ];
|
||||
nix.extraOptions =
|
||||
''
|
||||
extra-experimental-features = nix-command auto-allocate-uids cgroups
|
||||
extra-system-features = uid-range
|
||||
'';
|
||||
nix.nixPath = [ "nixpkgs=${nixpkgs}" ];
|
||||
};
|
||||
};
|
||||
|
||||
testScript = { nodes }: ''
|
||||
start_all()
|
||||
|
||||
host.succeed("nix --version >&2")
|
||||
|
||||
# Test that 'id' gives the expected result in various configurations.
|
||||
|
||||
# Existing UIDs, sandbox.
|
||||
host.succeed("nix build --no-auto-allocate-uids --sandbox -L --offline --impure --file ${./id-test.nix} --argstr name id-test-1")
|
||||
host.succeed("[[ $(cat ./result) = 'uid=1000(nixbld) gid=100(nixbld) groups=100(nixbld)' ]]")
|
||||
|
||||
# Existing UIDs, no sandbox.
|
||||
host.succeed("nix build --no-auto-allocate-uids --no-sandbox -L --offline --impure --file ${./id-test.nix} --argstr name id-test-2")
|
||||
host.succeed("[[ $(cat ./result) = 'uid=30001(nixbld1) gid=30000(nixbld) groups=30000(nixbld)' ]]")
|
||||
|
||||
# Auto-allocated UIDs, sandbox.
|
||||
host.succeed("nix build --auto-allocate-uids --sandbox -L --offline --impure --file ${./id-test.nix} --argstr name id-test-3")
|
||||
host.succeed("[[ $(cat ./result) = 'uid=1000(nixbld) gid=100(nixbld) groups=100(nixbld)' ]]")
|
||||
|
||||
# Auto-allocated UIDs, no sandbox.
|
||||
host.succeed("nix build --auto-allocate-uids --no-sandbox -L --offline --impure --file ${./id-test.nix} --argstr name id-test-4")
|
||||
host.succeed("[[ $(cat ./result) = 'uid=872415232 gid=30000(nixbld) groups=30000(nixbld)' ]]")
|
||||
|
||||
# Auto-allocated UIDs, UID range, sandbox.
|
||||
host.succeed("nix build --auto-allocate-uids --sandbox -L --offline --impure --file ${./id-test.nix} --argstr name id-test-5 --arg uidRange true")
|
||||
host.succeed("[[ $(cat ./result) = 'uid=0(root) gid=0(root) groups=0(root)' ]]")
|
||||
|
||||
# Auto-allocated UIDs, UID range, no sandbox.
|
||||
host.fail("nix build --auto-allocate-uids --no-sandbox -L --offline --impure --file ${./id-test.nix} --argstr name id-test-6 --arg uidRange true")
|
||||
|
||||
# Run systemd-nspawn in a Nix build.
|
||||
host.succeed("nix build --auto-allocate-uids --sandbox -L --offline --impure --file ${./systemd-nspawn.nix} --argstr nixpkgs ${nixpkgs}")
|
||||
host.succeed("[[ $(cat ./result/msg) = 'Hello World' ]]")
|
||||
'';
|
||||
|
||||
})
|
||||
8
tests/id-test.nix
Normal file
8
tests/id-test.nix
Normal file
|
|
@ -0,0 +1,8 @@
|
|||
{ name, uidRange ? false }:
|
||||
|
||||
with import <nixpkgs> {};
|
||||
|
||||
runCommand name
|
||||
{ requiredSystemFeatures = if uidRange then ["uid-range"] else [];
|
||||
}
|
||||
"id; id > $out"
|
||||
78
tests/systemd-nspawn.nix
Normal file
78
tests/systemd-nspawn.nix
Normal file
|
|
@ -0,0 +1,78 @@
|
|||
{ nixpkgs }:
|
||||
|
||||
let
|
||||
|
||||
machine = { config, pkgs, ... }:
|
||||
{
|
||||
system.stateVersion = "22.05";
|
||||
boot.isContainer = true;
|
||||
systemd.services.console-getty.enable = false;
|
||||
networking.dhcpcd.enable = false;
|
||||
|
||||
services.httpd = {
|
||||
enable = true;
|
||||
adminAddr = "nixos@example.org";
|
||||
};
|
||||
|
||||
systemd.services.test = {
|
||||
wantedBy = [ "multi-user.target" ];
|
||||
after = [ "httpd.service" ];
|
||||
script = ''
|
||||
source /.env
|
||||
echo "Hello World" > $out/msg
|
||||
ls -lR /dev > $out/dev
|
||||
${pkgs.curl}/bin/curl -sS --fail http://localhost/ > $out/page.html
|
||||
'';
|
||||
unitConfig = {
|
||||
FailureAction = "exit-force";
|
||||
FailureActionExitStatus = 42;
|
||||
SuccessAction = "exit-force";
|
||||
};
|
||||
};
|
||||
};
|
||||
|
||||
cfg = (import (nixpkgs + "/nixos/lib/eval-config.nix") {
|
||||
modules = [ machine ];
|
||||
system = "x86_64-linux";
|
||||
});
|
||||
|
||||
config = cfg.config;
|
||||
|
||||
in
|
||||
|
||||
with cfg._module.args.pkgs;
|
||||
|
||||
runCommand "test"
|
||||
{ buildInputs = [ config.system.path ];
|
||||
requiredSystemFeatures = [ "uid-range" ];
|
||||
toplevel = config.system.build.toplevel;
|
||||
}
|
||||
''
|
||||
root=$(pwd)/root
|
||||
mkdir -p $root $root/etc
|
||||
|
||||
export > $root/.env
|
||||
|
||||
# Make /run a tmpfs to shut up a systemd warning.
|
||||
mkdir /run
|
||||
mount -t tmpfs none /run
|
||||
chmod 0700 /run
|
||||
|
||||
mount -t cgroup2 none /sys/fs/cgroup
|
||||
|
||||
mkdir -p $out
|
||||
|
||||
touch /etc/os-release
|
||||
echo a5ea3f98dedc0278b6f3cc8c37eeaeac > /etc/machine-id
|
||||
|
||||
SYSTEMD_NSPAWN_UNIFIED_HIERARCHY=1 \
|
||||
${config.systemd.package}/bin/systemd-nspawn \
|
||||
--keep-unit \
|
||||
-M ${config.networking.hostName} -D "$root" \
|
||||
--register=no \
|
||||
--resolv-conf=off \
|
||||
--bind-ro=/nix/store \
|
||||
--bind=$out \
|
||||
--private-network \
|
||||
$toplevel/init
|
||||
''
|
||||
Loading…
Reference in a new issue