From 0085494e350c72599fc5c0e00422885d80b3c660 Mon Sep 17 00:00:00 2001 From: Miguel Angel Ajo Date: Mon, 19 Sep 2022 17:15:24 +0200 Subject: [PATCH] Support overlayfs whiteouts on checkout Introduces an intermediate format for overlayfs storage, where .wh-ostree. prefixed files will be converted into char 0:0 whiteout devices used by overlayfs to mark deletions across layers. The CI scripts now uses a volume for the scratch directories previously in /var/tmp otherwise we cannot create whiteout devices into an overlayfs mounted filesystem. Related-Issue: #2712 (cherry picked from commit e234b630f85b97e48ecf45d5aaba9b1aa64e6b54) --- .github/workflows/tests.yml | 8 +- Makefile-tests.am | 1 + bash/ostree | 1 + man/ostree-checkout.xml | 11 ++ src/libostree/ostree-repo-checkout.c | 129 ++++++++++++++++++++- src/libostree/ostree-repo.h | 5 +- src/libostree/ostree-sysroot-deploy.c | 2 +- src/ostree/ot-builtin-checkout.c | 7 +- tests/archive-test.sh | 7 +- tests/basic-test.sh | 29 ++++- tests/kolainst/data-shared/libtest-core.sh | 7 ++ tests/libtest.sh | 52 ++++++++- tests/test-admin-deploy-whiteouts.sh | 42 +++++++ 13 files changed, 292 insertions(+), 9 deletions(-) create mode 100755 tests/test-admin-deploy-whiteouts.sh --- a/Makefile-tests.am +++ b/Makefile-tests.am @@ -107,6 +107,7 @@ _installed_or_uninstalled_test_scripts = \ tests/test-admin-deploy-nomerge.sh \ tests/test-admin-deploy-none.sh \ tests/test-admin-deploy-bootid-gc.sh \ + tests/test-admin-deploy-whiteouts.sh \ tests/test-osupdate-dtb.sh \ tests/test-admin-instutil-set-kargs.sh \ tests/test-admin-upgrade-not-backwards.sh \ diff --git a/bash/ostree b/bash/ostree index 46363315..6f3b86ea 100644 --- a/bash/ostree +++ b/bash/ostree @@ -249,6 +249,7 @@ _ostree_checkout() { --union-identical --user-mode -U --whiteouts + --process-passthrough-whiteouts " local options_with_args=" diff --git a/man/ostree-checkout.xml b/man/ostree-checkout.xml index 4ed53a91..8f7d4f9b 100644 --- a/man/ostree-checkout.xml +++ b/man/ostree-checkout.xml @@ -114,6 +114,17 @@ License along with this library. If not, see . + + + + + Enable overlayfs whiteout extraction into 0:0 character devices. + Overlayfs whiteouts are encoded inside ostree as .ostree-wh.filename + and extracted as 0:0 character devices. This is useful to carry + container storage embedded into ostree. + + + diff --git a/src/libostree/ostree-repo-checkout.c b/src/libostree/ostree-repo-checkout.c index 663292a9..7c7d0cc7 100644 --- a/src/libostree/ostree-repo-checkout.c +++ b/src/libostree/ostree-repo-checkout.c @@ -35,6 +35,8 @@ #define WHITEOUT_PREFIX ".wh." #define OPAQUE_WHITEOUT_NAME ".wh..wh..opq" +#define OVERLAYFS_WHITEOUT_PREFIX ".ostree-wh." + /* Per-checkout call state/caching */ typedef struct { GString *path_buf; /* buffer for real path if filtering enabled */ @@ -582,6 +584,117 @@ checkout_file_hardlink (OstreeRepo *self, return TRUE; } +static gboolean +_checkout_overlayfs_whiteout_at_no_overwrite (OstreeRepoCheckoutAtOptions *options, + int destination_dfd, + const char *destination_name, + GFileInfo *file_info, + GVariant *xattrs, + gboolean *found_exant_file, + GCancellable *cancellable, + GError **error) +{ + if (found_exant_file != NULL) + *found_exant_file = FALSE; + guint32 file_mode = g_file_info_get_attribute_uint32 (file_info, "unix::mode"); + if (mknodat(destination_dfd, destination_name, (file_mode & ~S_IFMT) | S_IFCHR, (dev_t)0) < 0) + { + if (errno == EEXIST && found_exant_file != NULL) + { + *found_exant_file = TRUE; + return TRUE; + } + return glnx_throw_errno_prefix (error, "Creating whiteout char device"); + } + if (options->mode != OSTREE_REPO_CHECKOUT_MODE_USER) + { + if (xattrs != NULL && + !glnx_dfd_name_set_all_xattrs(destination_dfd, destination_name, xattrs, + cancellable, error)) + return glnx_throw_errno_prefix (error, "Setting xattrs for whiteout char device"); + + if (TEMP_FAILURE_RETRY(fchownat(destination_dfd, destination_name, + g_file_info_get_attribute_uint32 (file_info, "unix::uid"), + g_file_info_get_attribute_uint32 (file_info, "unix::gid"), + AT_SYMLINK_NOFOLLOW) < 0)) + return glnx_throw_errno_prefix (error, "fchownat"); + if (TEMP_FAILURE_RETRY (fchmodat (destination_dfd, destination_name, file_mode & ~S_IFMT, 0)) < 0) + return glnx_throw_errno_prefix (error, "fchmodat %s to 0%o", destination_name, file_mode & ~S_IFMT); + } + + return TRUE; +} + +static gboolean +_checkout_overlayfs_whiteout_at (OstreeRepo *repo, + OstreeRepoCheckoutAtOptions *options, + int destination_dfd, + const char *destination_name, + GFileInfo *file_info, + GVariant *xattrs, + GCancellable *cancellable, + GError **error) +{ + gboolean found_exant_file = FALSE; + if (!_checkout_overlayfs_whiteout_at_no_overwrite(options, destination_dfd, destination_name, + file_info, xattrs,&found_exant_file, + cancellable, error)) + return FALSE; + + if (!found_exant_file) + return TRUE; + + guint32 uid = g_file_info_get_attribute_uint32 (file_info, "unix::uid"); + guint32 gid = g_file_info_get_attribute_uint32 (file_info, "unix::gid"); + guint32 file_mode = g_file_info_get_attribute_uint32 (file_info, "unix::mode"); + + struct stat dest_stbuf; + + switch(options->overwrite_mode) + { + case OSTREE_REPO_CHECKOUT_OVERWRITE_NONE: + return FALSE; + case OSTREE_REPO_CHECKOUT_OVERWRITE_UNION_FILES: + if (!ot_ensure_unlinked_at (destination_dfd, destination_name, error)) + return FALSE; + return _checkout_overlayfs_whiteout_at_no_overwrite(options, destination_dfd, destination_name, + file_info, xattrs, NULL, cancellable, error); + case OSTREE_REPO_CHECKOUT_OVERWRITE_ADD_FILES: + return TRUE; + + case OSTREE_REPO_CHECKOUT_OVERWRITE_UNION_IDENTICAL: + if (!glnx_fstatat(destination_dfd, destination_name, &dest_stbuf, AT_SYMLINK_NOFOLLOW, + error)) + return FALSE; + if (!(repo->disable_xattrs || repo->mode == OSTREE_REPO_MODE_BARE_USER_ONLY)) + { + g_autoptr(GVariant) fs_xattrs; + if (!glnx_dfd_name_get_all_xattrs (destination_dfd, destination_name, + &fs_xattrs, cancellable, error)) + return FALSE; + if (!g_variant_equal(fs_xattrs, xattrs)) + return glnx_throw(error, "existing destination file %s xattrs don't match", + destination_name); + } + if (options->mode != OSTREE_REPO_CHECKOUT_MODE_USER) + { + if (gid != dest_stbuf.st_gid) + return glnx_throw(error, "existing destination file %s does not match gid %d", + destination_name, gid); + + if (uid != dest_stbuf.st_uid) + return glnx_throw(error, "existing destination file %s does not match uid %d", + destination_name, gid); + + if ((file_mode & ALLPERMS) != (dest_stbuf.st_mode & ALLPERMS)) + return glnx_throw(error, "existing destination file %s does not match mode %o", + destination_name, file_mode); + } + break; + } + return TRUE; +} + static gboolean checkout_one_file_at (OstreeRepo *repo, OstreeRepoCheckoutAtOptions *options, @@ -603,7 +716,8 @@ checkout_one_file_at (OstreeRepo *repo, /* FIXME - avoid the GFileInfo here */ g_autoptr(GFileInfo) source_info = NULL; - if (!ostree_repo_load_file (repo, checksum, NULL, &source_info, NULL, + g_autoptr(GVariant) source_xattrs = NULL; + if (!ostree_repo_load_file (repo, checksum, NULL, &source_info, &source_xattrs, cancellable, error)) return FALSE; @@ -623,6 +737,7 @@ checkout_one_file_at (OstreeRepo *repo, const gboolean is_unreadable = (!is_symlink && (source_mode & S_IRUSR) == 0); const gboolean is_whiteout = (!is_symlink && options->process_whiteouts && g_str_has_prefix (destination_name, WHITEOUT_PREFIX)); + const gboolean is_overlayfs_whiteout = (!is_symlink && g_str_has_prefix (destination_name, OVERLAYFS_WHITEOUT_PREFIX)); const gboolean is_reg_zerosized = (!is_symlink && g_file_info_get_size (source_info) == 0); const gboolean override_user_unreadable = (options->mode == OSTREE_REPO_CHECKOUT_MODE_USER && is_unreadable); @@ -643,6 +758,18 @@ checkout_one_file_at (OstreeRepo *repo, need_copy = FALSE; } + else if (is_overlayfs_whiteout && options->process_passthrough_whiteouts) + { + const char *name = destination_name + (sizeof (OVERLAYFS_WHITEOUT_PREFIX) - 1); + + if (!name[0]) + return glnx_throw (error, "Invalid empty overlayfs whiteout '%s'", name); + + g_assert (name[0] != '/'); /* Sanity */ + + return _checkout_overlayfs_whiteout_at(repo, options, destination_dfd, name, + source_info, source_xattrs, cancellable, error); + } else if (is_reg_zerosized || override_user_unreadable) { /* In https://github.com/ostreedev/ostree/commit/673cacd633f9d6b653cdea530657d3e780a41bbd we diff --git a/src/libostree/ostree-repo.h b/src/libostree/ostree-repo.h index 98571170..b3d7f986 100644 --- a/src/libostree/ostree-repo.h +++ b/src/libostree/ostree-repo.h @@ -989,8 +989,9 @@ typedef struct { gboolean force_copy; /* Since: 2017.6 */ gboolean bareuseronly_dirs; /* Since: 2017.7 */ gboolean force_copy_zerosized; /* Since: 2018.9 */ - gboolean unused_bools[4]; - /* 4 byte hole on 64 bit */ + gboolean process_passthrough_whiteouts; + gboolean unused_bools[3]; + /* 3 byte hole on 64 bit */ const char *subpath; diff --git a/src/libostree/ostree-sysroot-deploy.c b/src/libostree/ostree-sysroot-deploy.c index 404f336f..5c98103b 100644 --- a/src/libostree/ostree-sysroot-deploy.c +++ b/src/libostree/ostree-sysroot-deploy.c @@ -641,7 +641,7 @@ checkout_deployment_tree (OstreeSysroot *sysroot, return FALSE; /* Generate hardlink farm, then opendir it */ - OstreeRepoCheckoutAtOptions checkout_opts = { 0, }; + OstreeRepoCheckoutAtOptions checkout_opts = { .process_passthrough_whiteouts = TRUE }; if (!ostree_repo_checkout_at (repo, &checkout_opts, osdeploy_dfd, checkout_target_name, csum, cancellable, error)) diff --git a/src/ostree/ot-builtin-checkout.c b/src/ostree/ot-builtin-checkout.c index d69c8b0b..bfa43885 100644 --- a/src/ostree/ot-builtin-checkout.c +++ b/src/ostree/ot-builtin-checkout.c @@ -37,6 +37,7 @@ static gboolean opt_union; static gboolean opt_union_add; static gboolean opt_union_identical; static gboolean opt_whiteouts; +static gboolean opt_process_passthrough_whiteouts; static gboolean opt_from_stdin; static char *opt_from_file; static gboolean opt_disable_fsync; @@ -77,6 +78,7 @@ static GOptionEntry options[] = { { "union-add", 0, 0, G_OPTION_ARG_NONE, &opt_union_add, "Keep existing files/directories, only add new", NULL }, { "union-identical", 0, 0, G_OPTION_ARG_NONE, &opt_union_identical, "When layering checkouts, error out if a file would be replaced with a different version, but add new files and directories", NULL }, { "whiteouts", 0, 0, G_OPTION_ARG_NONE, &opt_whiteouts, "Process 'whiteout' (Docker style) entries", NULL }, + { "process-passthrough-whiteouts", 0, 0, G_OPTION_ARG_NONE, &opt_process_passthrough_whiteouts, "Enable overlayfs whiteout extraction into char 0:0 devices", NULL }, { "allow-noent", 0, 0, G_OPTION_ARG_NONE, &opt_allow_noent, "Do nothing if specified path does not exist", NULL }, { "from-stdin", 0, 0, G_OPTION_ARG_NONE, &opt_from_stdin, "Process many checkouts from standard input", NULL }, { "from-file", 0, 0, G_OPTION_ARG_STRING, &opt_from_file, "Process many checkouts from input file", "FILE" }, @@ -129,7 +131,8 @@ process_one_checkout (OstreeRepo *repo, if (opt_disable_cache || opt_whiteouts || opt_require_hardlinks || opt_union_add || opt_force_copy || opt_force_copy_zerosized || opt_bareuseronly_dirs || opt_union_identical || - opt_skiplist_file || opt_selinux_policy || opt_selinux_prefix) + opt_skiplist_file || opt_selinux_policy || opt_selinux_prefix || + opt_process_passthrough_whiteouts) { OstreeRepoCheckoutAtOptions checkout_options = { 0, }; @@ -162,6 +165,8 @@ process_one_checkout (OstreeRepo *repo, } if (opt_whiteouts) checkout_options.process_whiteouts = TRUE; + if (opt_process_passthrough_whiteouts) + checkout_options.process_passthrough_whiteouts = TRUE; if (subpath) checkout_options.subpath = subpath; diff --git a/tests/archive-test.sh b/tests/archive-test.sh index b6d84979..6b45790e 100644 --- a/tests/archive-test.sh +++ b/tests/archive-test.sh @@ -71,6 +71,11 @@ mkdir -p test-overlays date > test-overlays/overlaid-file $OSTREE commit ${COMMIT_ARGS} -b test-base --base test2 --owner-uid 42 --owner-gid 42 test-overlays/ $OSTREE ls -R test-base > ls.txt -assert_streq "$(wc -l < ls.txt)" 14 +if can_create_whiteout_devices; then + assert_streq "$(wc -l < ls.txt)" 17 +else + assert_streq "$(wc -l < ls.txt)" 14 +fi + assert_streq "$(grep '42.*42' ls.txt | wc -l)" 2 echo "ok commit overlay base" diff --git a/tests/basic-test.sh b/tests/basic-test.sh index 04506c3d..0878e6f6 100644 --- a/tests/basic-test.sh +++ b/tests/basic-test.sh @@ -19,7 +19,7 @@ set -euo pipefail -echo "1..$((87 + ${extra_basic_tests:-0}))" +echo "1..$((89 + ${extra_basic_tests:-0}))" CHECKOUT_U_ARG="" CHECKOUT_H_ARGS="-H" @@ -1187,3 +1187,30 @@ if test "$(id -u)" != "0"; then else echo "ok # SKIP not run when root" fi + +if ! skip_one_without_whiteouts_devices; then + cd ${test_tmpdir} + rm checkout-test2 -rf + $OSTREE checkout test2 checkout-test2 + + assert_not_has_file checkout-test2/whiteouts/whiteout + assert_not_has_file checkout-test2/whiteouts/whiteout2 + assert_has_file checkout-test2/whiteouts/.ostree-wh.whiteout + assert_has_file checkout-test2/whiteouts/.ostree-wh.whiteout2 + + echo "ok checkout: no whiteout passthrough by default" +fi + +if ! skip_one_without_whiteouts_devices; then + cd ${test_tmpdir} + rm checkout-test2 -rf + $OSTREE checkout --process-passthrough-whiteouts test2 checkout-test2 + + assert_not_has_file checkout-test2/whiteouts/.ostree-wh.whiteout + assert_not_has_file checkout-test2/whiteouts/.ostree-wh.whiteout2 + + assert_is_whiteout_device checkout-test2/whiteouts/whiteout + assert_is_whiteout_device checkout-test2/whiteouts/whiteout2 + + echo "ok checkout: whiteout with overlayfs passthrough processing" +fi diff --git a/tests/libtest.sh b/tests/libtest.sh index 686f08dc..5830f210 100755 --- a/tests/libtest.sh +++ b/tests/libtest.sh @@ -148,6 +148,20 @@ if ! have_selinux_relabel; then fi echo done +# whiteout char 0:0 devices can be created as regular users, but +# cannot be created inside containers mounted via overlayfs +can_create_whiteout_devices() { + mknod -m 000 ${test_tmpdir}/.test-whiteout c 0 0 || return 1 + rm -f ${test_tmpdir}/.test-whiteout + return 0 +} + +echo -n checking for overlayfs whiteouts... +if ! can_create_whiteout_devices; then + export OSTREE_NO_WHITEOUTS=1 +fi +echo done + if test -n "${OT_TESTS_DEBUG:-}"; then set -x fi @@ -245,6 +259,15 @@ setup_test_repository () { ln -s nonexistent baz/alink mkdir baz/another/ echo x > baz/another/y + + # if we are running inside a container we cannot test + # the overlayfs whiteout marker passthrough + if ! test -n "${OSTREE_NO_WHITEOUTS:-}"; then + mkdir whiteouts + touch whiteouts/.ostree-wh.whiteout + touch whiteouts/.ostree-wh.whiteout2 + chmod 755 whiteouts/.ostree-wh.whiteout2 + fi umask "${oldumask}" cd ${test_tmpdir}/files @@ -406,7 +429,7 @@ setup_os_repository () { mkdir osdata cd osdata kver=3.6.0 - mkdir -p usr/bin ${bootdir} usr/lib/modules/${kver} usr/share usr/etc + mkdir -p usr/bin ${bootdir} usr/lib/modules/${kver} usr/share usr/etc usr/container/layers/abcd kernel_path=${bootdir}/vmlinuz initramfs_path=${bootdir}/initramfs.img # the HMAC file is only in /usr/lib/modules @@ -449,6 +472,17 @@ EOF mkdir -p usr/etc/testdirectory echo "a default daemon file" > usr/etc/testdirectory/test + # if we are running inside a container we cannot test + # the overlayfs whiteout marker passthrough + if ! test -n "${OSTREE_NO_WHITEOUTS:-}"; then + # overlayfs whiteout passhthrough marker files + touch usr/container/layers/abcd/.ostree-wh.whiteout + chmod 400 usr/container/layers/abcd/.ostree-wh.whiteout + + touch usr/container/layers/abcd/.ostree-wh.whiteout2 + chmod 777 usr/container/layers/abcd/.ostree-wh.whiteout2 + fi + ${CMD_PREFIX} ostree --repo=${test_tmpdir}/testos-repo commit ${bootable_flag} --add-metadata-string version=1.0.9 -b testos/buildmain/x86_64-runtime -s "Build" # Ensure these commits have distinct second timestamps @@ -588,6 +622,22 @@ skip_without_user_xattrs () { fi } +# Usage: if ! skip_one_without_whiteouts_devices; then ... more tests ...; fi +skip_one_without_whiteouts_devices() { + if ! can_create_whiteout_devices; then + echo "ok # SKIP - this test requires whiteout device support (test outside containers)" + return 0 + else + return 1 + fi +} + +skip_without_whiteouts_devices () { + if ! can_create_whiteout_devices; then + skip "this test requires whiteout device support (test outside containers)" + fi +} + _have_systemd_and_libmount='' have_systemd_and_libmount() { if test "${_have_systemd_and_libmount}" = ''; then diff --git a/tests/test-admin-deploy-whiteouts.sh b/tests/test-admin-deploy-whiteouts.sh new file mode 100755 index 00000000..66421949 --- /dev/null +++ b/tests/test-admin-deploy-whiteouts.sh @@ -0,0 +1,42 @@ +#!/bin/bash +# +# Copyright (C) 2022 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 $0)/libtest.sh + +skip_without_whiteouts_devices + +# Exports OSTREE_SYSROOT so --sysroot not needed. +setup_os_repository "archive" "syslinux" +${CMD_PREFIX} ostree --repo=sysroot/ostree/repo pull-local --remote=testos testos-repo testos/buildmain/x86_64-runtime + +echo "1..3" +${CMD_PREFIX} ostree admin deploy --os=testos --karg=root=LABEL=foo --karg=testkarg=1 testos:testos/buildmain/x86_64-runtime +origdeployment=$(${CMD_PREFIX} ostree admin --sysroot=sysroot --print-current-dir) + +assert_is_whiteout_device "${origdeployment}"/usr/container/layers/abcd/whiteout +echo "ok whiteout deployment" + +assert_not_has_file "${origdeployment}"/usr/container/layers/abcd/.ostree-wh.whiteout +echo "ok .ostree-wh.whiteout not created" + +assert_file_has_mode "${origdeployment}"/usr/container/layers/abcd/whiteout 400 +assert_file_has_mode "${origdeployment}"/usr/container/layers/abcd/whiteout2 777 +echo "ok whiteout permissions are preserved" -- 2.37.3