diff --git a/Makefile-tests.am b/Makefile-tests.am index eae9f3182c..c6f9420eee 100644 --- a/Makefile-tests.am +++ b/Makefile-tests.am @@ -105,6 +105,7 @@ _installed_or_uninstalled_test_scripts = \ tests/test-admin-deploy-syslinux.sh \ tests/test-admin-deploy-bootprefix.sh \ tests/test-admin-deploy-composefs.sh \ + tests/test-admin-deploy-var.sh \ tests/test-admin-deploy-2.sh \ tests/test-admin-deploy-karg.sh \ tests/test-admin-deploy-switch.sh \ diff --git a/docs/var.md b/docs/var.md index 6ab52cc7d6..61480d8c7e 100644 --- a/docs/var.md +++ b/docs/var.md @@ -9,6 +9,31 @@ nav_order: 6 1. TOC {:toc} +## Default commit/image /var handling + +As of OSTree 2024.3, when a commit is "deployed" (queued to boot), +the initial content of `/var` in a commit will be placed into the +"stateroot" (default `var`) if the stateroot `var` is empty. + +The semantics of this are intended to match that of Docker "volumes"; +consider that ostree systems have the equivalent of +`VOLUME /var` +by default. + +It is still strongly recommended to use systemd `tmpfiles.d` snippets +to populate directory structure and the like in `/var` on firstboot, +because this is more resilent. + +Even better, use `StateDirectory=` for systemd units. + +### ostree container /var + +Some earlier versions of the ostree-container stack migrated content in `/var` +in container images into `/usr/share/factory/var` (per below). This has +been reverted, and the semantics defer to the above ostree semantic. + +## Previous /var handling via /usr/share/factory/var + As of OSTree 2023.8, the `/usr/lib/tmpfiles.d/ostree-tmpfiles.conf` file gained this snippet: ```text @@ -18,7 +43,7 @@ As of OSTree 2023.8, the `/usr/lib/tmpfiles.d/ostree-tmpfiles.conf` file gained C+! /var - - - - - ``` -This is inert by default. However, there is a pending change in the ostree-container stack which will move all files in `/var` from fetched container images into `/usr/share/factory/var`. And other projects in the ostree ecosystem are now recommended do this by default. +This is inert by default. As of version 0.13 of the ostree-ext project, content in `/var` in fetched container images is moved to `/usr/share/factory/var`. This is no longer recommended. Together, this will have the semantic that on OS updates, on the next boot (early in boot), any new files/directories will be copied. For more information on this, see [`man tmpfiles.d`](https://man7.org/linux/man-pages/man5/tmpfiles.d.5.html). diff --git a/src/boot/ostree-tmpfiles.conf b/src/boot/ostree-tmpfiles.conf index 1877e44d13..c1b5048037 100644 --- a/src/boot/ostree-tmpfiles.conf +++ b/src/boot/ostree-tmpfiles.conf @@ -18,6 +18,6 @@ d /run/ostree 0755 root root - # https://github.com/ostreedev/ostree/issues/393 R! /var/tmp/ostree-unlock-ovl.* # Automatically propagate all /var content from /usr/share/factory/var; -# the ostree-container stack is being changed to do this, and we want to -# encourage ostree use cases in general to follow this pattern. +# NOTE: This is now considered a mistake, and will likely be reverted. +# As of OSTree 2024.3, content from the initial deployment is used. C+! /var - - - - - diff --git a/src/libostree/ostree-sysroot-deploy.c b/src/libostree/ostree-sysroot-deploy.c index 49c3a6abbd..2ed1d2148d 100644 --- a/src/libostree/ostree-sysroot-deploy.c +++ b/src/libostree/ostree-sysroot-deploy.c @@ -48,6 +48,9 @@ #include "ostree.h" #include "otcore.h" +// The path to the systemd tmpfiles.d directory. +#define USRLIB_TMPFILES "usr/lib/tmpfiles.d" + #ifdef HAVE_LIBSYSTEMD #define OSTREE_VARRELABEL_ID \ SD_ID128_MAKE (da, 67, 9b, 08, ac, d3, 45, 04, b7, 89, d9, 6f, 81, 8e, a7, 81) @@ -657,6 +660,7 @@ checkout_deployment_tree (OstreeSysroot *sysroot, OstreeRepo *repo, OstreeDeploy /* Generate hardlink farm, then opendir it */ OstreeRepoCheckoutAtOptions checkout_opts = { .process_passthrough_whiteouts = TRUE }; + if (!ostree_repo_checkout_at (repo, &checkout_opts, osdeploy_dfd, checkout_target_name, csum, cancellable, error)) return FALSE; @@ -3088,33 +3092,81 @@ _ostree_deployment_set_bootconfig_from_kargs (OstreeDeployment *deployment, } } -// Perform some basic static analysis and emit warnings for things -// that are likely to fail later. This function only returns -// a hard error if something unexpected (e.g. I/O error) occurs. +// If the stateroot /var is uninitialized, copy the /var content from the deployment. +// This is intended to mirror the semantics of Docker volumes. static gboolean -lint_deployment_fs (OstreeSysroot *self, OstreeDeployment *deployment, int deployment_dfd, - GCancellable *cancellable, GError **error) +prepare_deployment_var (OstreeSysroot *self, OstreeDeployment *deployment, int deployment_dfd, + GCancellable *cancellable, GError **error) { - g_auto (GLnxDirFdIterator) dfd_iter = { - 0, - }; - gboolean exists; + GLNX_AUTO_PREFIX_ERROR ("Preparing deployment /var", error); + + // Does the deployment have a var? If not, we're done. (Though this will probably + // cause problems at boot time) + { + g_auto (GLnxDirFdIterator) dfd_iter = { + 0, + }; + gboolean exists; - if (!ot_dfd_iter_init_allow_noent (deployment_dfd, "var", &dfd_iter, &exists, error)) + if (!ot_dfd_iter_init_allow_noent (deployment_dfd, "var", &dfd_iter, &exists, error)) + return FALSE; + if (!exists) + { + g_debug ("deployment has no /var"); + return TRUE; + } + } + + // Open the stateroot which holds the shared /var + const char *stateroot = ostree_deployment_get_osname (deployment); + g_autofree char *stateroot_path = g_build_filename ("ostree/deploy/", stateroot, "var", NULL); + glnx_autofd int stateroot_dfd = -1; + if (!glnx_opendirat (self->sysroot_fd, stateroot_path, FALSE, &stateroot_dfd, error)) + return glnx_prefix_error (error, "Opening stateroot"); + + // Check if the stateroot is empty + { + g_auto (GLnxDirFdIterator) dfd_iter = { + 0, + }; + + if (!glnx_dirfd_iterator_init_at (stateroot_dfd, ".", FALSE, &dfd_iter, error)) + return FALSE; + + struct dirent *dent; + + if (!glnx_dirfd_iterator_next_dent (&dfd_iter, &dent, cancellable, error)) + return FALSE; + + if (dent != NULL) + { + // We found existing content in the stateroot var, so we're done. + // There is no merge semantics. + g_debug ("Stateroot %s is non-empty", stateroot); + return TRUE; + } + } + + g_debug ("Copying initial deployment /var"); + // At this point we should initialize the stateroot var with the content from + // the commit/image. Note we need to force a copy; hopefully reflinks are available. + OstreeRepoCheckoutAtOptions co_opts + = { .force_copy = TRUE, + .subpath = "/var", + .overwrite_mode = OSTREE_REPO_CHECKOUT_OVERWRITE_UNION_FILES }; + if (!ostree_repo_checkout_at (self->repo, &co_opts, stateroot_dfd, ".", + ostree_deployment_get_csum (deployment), cancellable, error)) return FALSE; - while (exists) - { - struct dirent *dent; - if (!glnx_dirfd_iterator_next_dent (&dfd_iter, &dent, cancellable, error)) + if (!glnx_fstatat_allow_noent (deployment_dfd, USRLIB_TMPFILES, NULL, AT_SYMLINK_NOFOLLOW, error)) + return glnx_prefix_error (error, "Querying %s", USRLIB_TMPFILES); + if (errno == ENOENT) + { + g_debug ("deployment has no %s", USRLIB_TMPFILES); + // OK, this OS doesn't appear to use systemd (or tmpfiles.d at least). For full + // backwards compatibility we create some standard things in the stateroot var. + if (!_ostree_sysroot_stateroot_legacy_var_init (stateroot_dfd, error)) return FALSE; - if (dent == NULL) - break; - - fprintf (stderr, - "note: Deploying commit %s which contains content in /var/%s that should be in " - "/usr/share/factory/var\n", - ostree_deployment_get_csum (deployment), dent->d_name); } return TRUE; @@ -3182,7 +3234,7 @@ sysroot_initialize_deployment (OstreeSysroot *self, const char *osname, const ch if (!prepare_deployment_etc (self, repo, new_deployment, deployment_dfd, cancellable, error)) return FALSE; - if (!lint_deployment_fs (self, new_deployment, deployment_dfd, cancellable, error)) + if (!prepare_deployment_var (self, new_deployment, deployment_dfd, cancellable, error)) return FALSE; ot_transfer_out_value (out_new_deployment, &new_deployment); diff --git a/src/libostree/ostree-sysroot-private.h b/src/libostree/ostree-sysroot-private.h index 8b9cadea08..297b3273a0 100644 --- a/src/libostree/ostree-sysroot-private.h +++ b/src/libostree/ostree-sysroot-private.h @@ -148,6 +148,8 @@ char *_ostree_sysroot_get_deployment_backing_relpath (OstreeDeployment *deployme gboolean _ostree_sysroot_rmrf_deployment (OstreeSysroot *sysroot, OstreeDeployment *deployment, GCancellable *cancellable, GError **error); +gboolean _ostree_sysroot_stateroot_legacy_var_init (int dfd, GError **error); + char *_ostree_sysroot_get_runstate_path (OstreeDeployment *deployment, const char *key); gboolean _ostree_sysroot_run_in_deployment (int deployment_dfd, const char *const *bwrap_argv, diff --git a/src/libostree/ostree-sysroot.c b/src/libostree/ostree-sysroot.c index dca69339ca..a19b049b32 100644 --- a/src/libostree/ostree-sysroot.c +++ b/src/libostree/ostree-sysroot.c @@ -1792,6 +1792,46 @@ ostree_sysroot_lock_finish (OstreeSysroot *self, GAsyncResult *result, GError ** return g_task_propagate_boolean ((GTask *)result, error); } +// This is a legacy subset of what happens normally via systemd tmpfiles.d; +// it is only run in the case that the deployment it self comes without +// usr/lib/tmpfiles.d +gboolean +_ostree_sysroot_stateroot_legacy_var_init (int dfd, GError **error) +{ + GLNX_AUTO_PREFIX_ERROR ("Legacy mode stateroot var initialization", error); + + /* This is a bit of a legacy hack...but we have to keep it around + * now. We're ensuring core subdirectories of /var exist. + */ + if (!glnx_ensure_dir (dfd, "tmp", 0777, error)) + return FALSE; + + if (fchmodat (dfd, "tmp", 01777, 0) < 0) + return glnx_throw_errno_prefix (error, "fchmod %s", "var/tmp"); + + if (!glnx_ensure_dir (dfd, "lib", 0777, error)) + return FALSE; + + /* This needs to be available and properly labeled early during the boot + * process (before tmpfiles.d kicks in), so that journald can flush logs from + * the first boot there. https://bugzilla.redhat.com/show_bug.cgi?id=1265295 + * */ + if (!glnx_ensure_dir (dfd, "log", 0755, error)) + return FALSE; + + if (!glnx_fstatat_allow_noent (dfd, "run", NULL, AT_SYMLINK_NOFOLLOW, error)) + return FALSE; + if (errno == ENOENT && symlinkat ("../run", dfd, "run") < 0) + return glnx_throw_errno_prefix (error, "Symlinking %s", "var/run"); + + if (!glnx_fstatat_allow_noent (dfd, "lock", NULL, AT_SYMLINK_NOFOLLOW, error)) + return FALSE; + if (errno == ENOENT && symlinkat ("../run/lock", dfd, "lock") < 0) + return glnx_throw_errno_prefix (error, "Symlinking %s", "var/lock"); + + return TRUE; +} + /** * ostree_sysroot_init_osname: * @self: Sysroot @@ -1823,31 +1863,6 @@ ostree_sysroot_init_osname (OstreeSysroot *self, const char *osname, GCancellabl if (mkdirat (dfd, "var", 0777) < 0) return glnx_throw_errno_prefix (error, "Creating %s", "var"); - /* This is a bit of a legacy hack...but we have to keep it around - * now. We're ensuring core subdirectories of /var exist. - */ - if (mkdirat (dfd, "var/tmp", 0777) < 0) - return glnx_throw_errno_prefix (error, "Creating %s", "var/tmp"); - - if (fchmodat (dfd, "var/tmp", 01777, 0) < 0) - return glnx_throw_errno_prefix (error, "fchmod %s", "var/tmp"); - - if (mkdirat (dfd, "var/lib", 0777) < 0) - return glnx_throw_errno_prefix (error, "Creating %s", "var/lib"); - - /* This needs to be available and properly labeled early during the boot - * process (before tmpfiles.d kicks in), so that journald can flush logs from - * the first boot there. https://bugzilla.redhat.com/show_bug.cgi?id=1265295 - * */ - if (mkdirat (dfd, "var/log", 0755) < 0) - return glnx_throw_errno_prefix (error, "Creating %s", "var/log"); - - if (symlinkat ("../run", dfd, "var/run") < 0) - return glnx_throw_errno_prefix (error, "Symlinking %s", "var/run"); - - if (symlinkat ("../run/lock", dfd, "var/lock") < 0) - return glnx_throw_errno_prefix (error, "Symlinking %s", "var/lock"); - if (!_ostree_sysroot_bump_mtime (self, error)) return FALSE; diff --git a/tests/test-admin-deploy-var.sh b/tests/test-admin-deploy-var.sh new file mode 100755 index 0000000000..2c79ca9f31 --- /dev/null +++ b/tests/test-admin-deploy-var.sh @@ -0,0 +1,76 @@ +#!/bin/bash +# +# Copyright (C) 2024 Red Hat, Inc. +# +# SPDX-License-Identifier: LGPL-2.0+ +# +# This library is free software; you can redistribute it and/or +# modify it under the terms of the GNU Lesser General Public +# License as published by the Free Software Foundation; either +# version 2 of the License, or (at your option) any later version. +# +# This library is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +# Lesser General Public License for more details. +# +# You should have received a copy of the GNU Lesser General Public +# License along with this library. If not, see . + +set -euox pipefail + +. $(dirname $0)/libtest.sh + +# Exports OSTREE_SYSROOT so --sysroot not needed. +setup_os_repository "archive" "syslinux" + +echo "initial ls" +ls -R sysroot/ostree/deploy/testos/var + +cd osdata +mkdir -p var/lib/ +echo somedata > var/lib/somefile +${CMD_PREFIX} ostree --repo=${test_tmpdir}/testos-repo commit -b testos/buildmain/x86_64-runtime +cd - +${CMD_PREFIX} ostree --repo=sysroot/ostree/repo pull-local --remote=testos testos-repo testos/buildmain/x86_64-runtime + +${CMD_PREFIX} ostree admin deploy --os=testos testos:testos/buildmain/x86_64-runtime +ls -R sysroot/ostree/deploy/testos/var +assert_file_has_content sysroot/ostree/deploy/testos/var/lib/somefile somedata +# We don't have tmpfiles here yet +assert_not_has_dir sysroot/ostree/deploy/*.0/usr/lib/tmpfiles.d +if ${CMD_PREFIX} ostree --repo=sysroot/ostree/repo ls testos/buildmain/x86_64-runtime /var/log; then + fatal "var/log in commit" +fi +# This one is created via legacy init w/o tmpfiles.d +assert_has_dir sysroot/ostree/deploy/testos/var/log + +tap_ok deployment var init + +cd osdata +echo someotherdata > var/lib/someotherfile +${CMD_PREFIX} ostree --repo=${test_tmpdir}/testos-repo commit -b testos/buildmain/x86_64-runtime +cd - +${CMD_PREFIX} ostree --repo=sysroot/ostree/repo pull-local --remote=testos testos-repo testos/buildmain/x86_64-runtime +${CMD_PREFIX} ostree admin deploy --os=testos testos:testos/buildmain/x86_64-runtime +assert_not_has_file sysroot/ostree/deploy/testos/var/lib/someotherfile + +tap_ok deployment var not updated + +${CMD_PREFIX} ostree admin undeploy 0 +${CMD_PREFIX} ostree admin undeploy 0 +rm sysroot/ostree/deploy/testos/var/* -rf + +cd osdata +mkdir -p usr/lib/tmpfiles.d +${CMD_PREFIX} ostree --repo=${test_tmpdir}/testos-repo commit -b testos/buildmain/x86_64-runtime +cd - +${CMD_PREFIX} ostree --repo=sysroot/ostree/repo pull-local --remote=testos testos-repo testos/buildmain/x86_64-runtime +${CMD_PREFIX} ostree admin deploy --os=testos testos:testos/buildmain/x86_64-runtime + +# Not in the commit, so not created via legacy init because we have tmpfiles.d +assert_not_has_dir sysroot/ostree/deploy/testos/var/log + +tap_ok deployment var w/o legacy + +tap_end