From 272378080241106862a9cca2e4e84857fe1aaf5c Mon Sep 17 00:00:00 2001

From: Lennart Poettering <lennart@poettering.net>

Date: Thu, 8 Oct 2015 22:31:56 +0200

Subject: [PATCH] install: follow unit file symlinks in /usr, but not /etc when

 looking for [Install] data

Some distributions use alias unit files via symlinks in /usr to cover

for legacy service names. With this change we'll allow "systemctl

enable" on such aliases.

Previously, our rule was that symlinks are user configuration that

"systemctl enable" + "systemctl disable" creates and removes, while unit

files is where the instructions to do so are store. As a result of the

rule we'd never read install information through symlinks, since that

would mix enablement state with installation instructions.

Now, the new rule is that only symlinks inside of /etc are

configuration. Unit files, and symlinks in /usr are now valid for

installation instructions.

This patch is quite a rework of the whole install logic, and makes the

following addional changes:

- Adds a complete test "test-instal-root" that tests the install logic

  pretty comprehensively.

- Never uses canonicalize_file_name(), because that's incompatible with

  operation relative to a specific root directory.

- unit_file_get_state() is reworked to return a proper error, and

  returns the state in a call-by-ref parameter. This cleans up confusion

  between the enum type and errno-like errors.

- The new logic puts a limit on how long to follow unit file symlinks:

  it will do so only for 64 steps at max.

- The InstallContext object's fields are renamed to will_process and

  has_processed (will_install and has_installed) since they are also

  used for deinstallation and all kinds of other operations.

- The root directory is always verified before use.

- install.c is reordered to place the exported functions together.

- Stricter rules are followed when traversing symlinks: the unit suffix

  must say identical, and it's not allowed to link between regular units

  and templated units.

- Various modernizations

- The "invalid" unit file state has been renamed to "bad", in order to

  avoid confusion between UNIT_FILE_INVALID and

  _UNIT_FILE_STATE_INVALID. Given that the state should normally not be

  seen and is not documented this should not be a problematic change.

  The new name is now documented however.

Fixes #1375, #1718, #1706

Cherry-picked from: 79413b673b45adc98dfeaec882bbdda2343cb2f9

Resolves: #1159308

---

 Makefile.am                           |   12 +-

 man/systemctl.xml                     |   14 +-

 src/core/dbus-manager.c               |    6 +-

 src/core/dbus-unit.c                  |    4 +-

 src/core/load-fragment.c              |    2 +-

 src/core/manager.c                    |    2 +-

 src/core/snapshot.c                   |    2 +-

 src/core/unit.c                       |   19 +-

 src/dbus1-generator/dbus1-generator.c |    2 +-

 src/firstboot/firstboot.c             |   18 +-

 src/shared/cgroup-util.c              |    6 +-

 src/shared/install.c                  | 1909 +++++++++++++++++++--------------

 src/shared/install.h                  |   46 +-

 src/shared/path-util.c                |   34 +

 src/shared/path-util.h                |   27 +

 src/shared/unit-name.c                |   32 +-

 src/shared/unit-name.h                |   14 +-

 src/shared/util.c                     |   21 +

 src/shared/util.h                     |    1 +

 src/systemctl/systemctl.c             |    6 +-

 src/sysv-generator/sysv-generator.c   |   10 +-

 src/test/test-install-root.c          |  663 ++++++++++++

 src/test/test-install.c               |   71 +-

 23 files changed, 1998 insertions(+), 923 deletions(-)

 create mode 100644 src/test/test-install-root.c

diff --git a/Makefile.am b/Makefile.am

index 3af720b..3a09e0a 100644

--- a/Makefile.am

+++ b/Makefile.am

@@ -1427,7 +1427,8 @@ tests += \

 	test-copy \

 	test-cap-list \

 	test-sigbus \

-	test-verbs

+	test-verbs \

+	test-install-root

 EXTRA_DIST += \

 	test/a.service \

@@ -1721,6 +1722,15 @@ test_verbs_SOURCES = \

 test_verbs_LDADD = \

 	libsystemd-shared.la

+test_install_root_SOURCES = \

+	src/test/test-install-root.c

+

+test_install_root_LDADD = \

+	libsystemd-units.la \

+	libsystemd-label.la \

+	libsystemd-internal.la \

+	libsystemd-shared.la

+

 test_namespace_LDADD = \

 	libsystemd-core.la

diff --git a/man/systemctl.xml b/man/systemctl.xml

index c6f5842..2d0678d 100644

--- a/man/systemctl.xml

+++ b/man/systemctl.xml

@@ -905,10 +905,11 @@ kobject-uevent 1 systemd-udevd-kernel.socket systemd-udevd.service

           <term><command>list-unit-files <optional><replaceable>PATTERN...</replaceable></optional></command></term>

           <listitem>

-            <para>List installed unit files. If one or more

-            <replaceable>PATTERN</replaceable>s are specified, only

-            units whose filename (just the last component of the path)

-            matches one of them are shown.</para>

+            <para>List installed unit files and their enablement state

+            (as reported by <command>is-enabled</command>). If one or

+            more <replaceable>PATTERN</replaceable>s are specified,

+            only units whose filename (just the last component of the

+            path) matches one of them are shown.</para>

           </listitem>

         </varlistentry>

@@ -1108,6 +1109,11 @@ kobject-uevent 1 systemd-udevd-kernel.socket systemd-udevd.service

                     <entry>Unit file is not enabled.</entry>

                     <entry>1</entry>

                   </row>

+                  <row>

+                    <entry><literal>bad</literal></entry>

+                    <entry>Unit file is invalid or another error occured. Note that <command>is-enabled</command> wil not actually return this state, but print an error message instead. However the unit file listing printed by <command>list-unit-files</command> might show it.</entry>

+                    <entry>> 0</entry>

+                  </row>

               </tgroup>

diff --git a/src/core/dbus-manager.c b/src/core/dbus-manager.c

index 1ec350e..faa124d 100644

--- a/src/core/dbus-manager.c

+++ b/src/core/dbus-manager.c

@@ -1530,9 +1530,9 @@ static int method_get_unit_file_state(sd_bus *bus, sd_bus_message *message, void

         scope = m->running_as == SYSTEMD_SYSTEM ? UNIT_FILE_SYSTEM : UNIT_FILE_USER;

-        state = unit_file_get_state(scope, NULL, name);

-        if (state < 0)

-                return state;

+        r = unit_file_get_state(scope, NULL, name, &state);

+        if (r < 0)

+                return r;

         return sd_bus_reply_method_return(message, "s", unit_file_state_to_string(state));

 }

diff --git a/src/core/dbus-unit.c b/src/core/dbus-unit.c

index 625d21a..227915e 100644

--- a/src/core/dbus-unit.c

+++ b/src/core/dbus-unit.c

@@ -919,7 +919,7 @@ static int bus_unit_set_transient_property(

                 if (r < 0)

                         return r;

-                if (!unit_name_is_valid(s, TEMPLATE_INVALID) || !endswith(s, ".slice"))

+                if (!unit_name_is_valid(s, UNIT_NAME_PLAIN) || !endswith(s, ".slice"))

                         return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid slice name %s", s);

                 if (isempty(s)) {

@@ -967,7 +967,7 @@ static int bus_unit_set_transient_property(

                         return r;

                 while ((r = sd_bus_message_read(message, "s", &other)) > 0) {

-                        if (!unit_name_is_valid(other, TEMPLATE_INVALID))

+                        if (!unit_name_is_valid(other, UNIT_NAME_PLAIN|UNIT_NAME_INSTANCE))

                                 return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid unit name %s", other);

                         if (mode != UNIT_CHECK) {

diff --git a/src/core/load-fragment.c b/src/core/load-fragment.c

index ec4cf4e..70c0918 100644

--- a/src/core/load-fragment.c

+++ b/src/core/load-fragment.c

@@ -3409,7 +3409,7 @@ static int open_follow(char **filename, FILE **_f, Set *names, char **_final) {

                  * unit name. */

                 name = basename(*filename);

-                if (unit_name_is_valid(name, TEMPLATE_VALID)) {

+                if (unit_name_is_valid(name, UNIT_NAME_ANY)) {

                         id = set_get(names, name);

                         if (!id) {

diff --git a/src/core/manager.c b/src/core/manager.c

index 7483a96..bde17ce 100644

--- a/src/core/manager.c

+++ b/src/core/manager.c

@@ -1328,7 +1328,7 @@ int manager_load_unit_prepare(

         t = unit_name_to_type(name);

-        if (t == _UNIT_TYPE_INVALID || !unit_name_is_valid(name, TEMPLATE_INVALID))

+        if (t == _UNIT_TYPE_INVALID || !unit_name_is_valid(name, UNIT_NAME_PLAIN|UNIT_NAME_INSTANCE))

                 return sd_bus_error_setf(e, SD_BUS_ERROR_INVALID_ARGS, "Unit name %s is not valid.", name);

         ret = manager_get_unit(m, name);

diff --git a/src/core/snapshot.c b/src/core/snapshot.c

index b1d8448..f222ec2 100644

--- a/src/core/snapshot.c

+++ b/src/core/snapshot.c

@@ -201,7 +201,7 @@ int snapshot_create(Manager *m, const char *name, bool cleanup, sd_bus_error *e,

         assert(_s);

         if (name) {

-                if (!unit_name_is_valid(name, TEMPLATE_INVALID))

+                if (!unit_name_is_valid(name, UNIT_NAME_PLAIN))

                         return sd_bus_error_setf(e, SD_BUS_ERROR_INVALID_ARGS, "Unit name %s is not valid.", name);

                 if (unit_name_to_type(name) != UNIT_SNAPSHOT)

diff --git a/src/core/unit.c b/src/core/unit.c

index 4fb2fd3..db5aa98 100644

--- a/src/core/unit.c

+++ b/src/core/unit.c

@@ -158,7 +158,7 @@ int unit_add_name(Unit *u, const char *text) {

         if (!s)

                 return -ENOMEM;

-        if (!unit_name_is_valid(s, TEMPLATE_INVALID))

+        if (!unit_name_is_valid(s, UNIT_NAME_PLAIN|UNIT_NAME_INSTANCE))

                 return -EINVAL;

         assert_se((t = unit_name_to_type(s)) >= 0);

@@ -3119,12 +3119,18 @@ int unit_following_set(Unit *u, Set **s) {

 }

 UnitFileState unit_get_unit_file_state(Unit *u) {

+        int r;

+

         assert(u);

-        if (u->unit_file_state < 0 && u->fragment_path)

-                u->unit_file_state = unit_file_get_state(

-                                u->manager->running_as == SYSTEMD_SYSTEM ? UNIT_FILE_SYSTEM : UNIT_FILE_USER,

-                                NULL, basename(u->fragment_path));

+        if (u->unit_file_state < 0 && u->fragment_path) {

+                r = unit_file_get_state(u->manager->running_as == SYSTEMD_SYSTEM ? UNIT_FILE_SYSTEM : UNIT_FILE_USER,

+                                        NULL,

+                                        basename(u->fragment_path),

+                                        &u->unit_file_state);

+                if (r < 0)

+                        u->unit_file_state = UNIT_FILE_BAD;

+        }

         return u->unit_file_state;

 }

@@ -3135,7 +3141,8 @@ int unit_get_unit_file_preset(Unit *u) {

         if (u->unit_file_preset < 0 && u->fragment_path)

                 u->unit_file_preset = unit_file_query_preset(

                                 u->manager->running_as == SYSTEMD_SYSTEM ? UNIT_FILE_SYSTEM : UNIT_FILE_USER,

-                                NULL, basename(u->fragment_path));

+                                NULL,

+                                basename(u->fragment_path));

         return u->unit_file_preset;

 }

diff --git a/src/dbus1-generator/dbus1-generator.c b/src/dbus1-generator/dbus1-generator.c

index 2e08af2..c909a4b 100644

--- a/src/dbus1-generator/dbus1-generator.c

+++ b/src/dbus1-generator/dbus1-generator.c

@@ -188,7 +188,7 @@ static int add_dbus(const char *path, const char *fname, const char *type) {

         }

         if (service) {

-                if (!unit_name_is_valid(service, TEMPLATE_INVALID)) {

+                if (!unit_name_is_valid(service, UNIT_NAME_PLAIN|UNIT_NAME_INSTANCE)) {

                         log_warning("Unit name %s is not valid, ignoring.", service);

                         return 0;

                 }

diff --git a/src/firstboot/firstboot.c b/src/firstboot/firstboot.c

index a37ca17..b77c1d8 100644

--- a/src/firstboot/firstboot.c

+++ b/src/firstboot/firstboot.c

@@ -50,8 +50,6 @@ static bool arg_copy_locale = false;

 static bool arg_copy_timezone = false;

 static bool arg_copy_root_password = false;

-#define prefix_roota(p) (arg_root ? (const char*) strjoina(arg_root, p) : (const char*) p)

-

 static void clear_string(char *x) {

         if (!x)

@@ -85,13 +83,13 @@ static void print_welcome(void) {

         if (done)

                 return;

-        os_release = prefix_roota("/etc/os-release");

+        os_release = prefix_roota(arg_root, "/etc/os-release");

         r = parse_env_file(os_release, NEWLINE,

                            "PRETTY_NAME", &pretty_name,

                            NULL);

         if (r == -ENOENT) {

-                os_release = prefix_roota("/usr/lib/os-release");

+                os_release = prefix_roota(arg_root, "/usr/lib/os-release");

                 r = parse_env_file(os_release, NEWLINE,

                                    "PRETTY_NAME", &pretty_name,

                                    NULL);

@@ -249,7 +247,7 @@ static int process_locale(void) {

         unsigned i = 0;

         int r;

-        etc_localeconf = prefix_roota("/etc/locale.conf");

+        etc_localeconf = prefix_roota(arg_root, "/etc/locale.conf");

         if (faccessat(AT_FDCWD, etc_localeconf, F_OK, AT_SYMLINK_NOFOLLOW) >= 0)

                 return 0;

@@ -323,7 +321,7 @@ static int process_timezone(void) {

         const char *etc_localtime, *e;

         int r;

-        etc_localtime = prefix_roota("/etc/localtime");

+        etc_localtime = prefix_roota(arg_root, "/etc/localtime");

         if (faccessat(AT_FDCWD, etc_localtime, F_OK, AT_SYMLINK_NOFOLLOW) >= 0)

                 return 0;

@@ -402,7 +400,7 @@ static int process_hostname(void) {

         const char *etc_hostname;

         int r;

-        etc_hostname = prefix_roota("/etc/hostname");

+        etc_hostname = prefix_roota(arg_root, "/etc/hostname");

         if (faccessat(AT_FDCWD, etc_hostname, F_OK, AT_SYMLINK_NOFOLLOW) >= 0)

                 return 0;

@@ -427,7 +425,7 @@ static int process_machine_id(void) {

         char id[SD_ID128_STRING_MAX];

         int r;

-        etc_machine_id = prefix_roota("/etc/machine-id");

+        etc_machine_id = prefix_roota(arg_root, "/etc/machine-id");

         if (faccessat(AT_FDCWD, etc_machine_id, F_OK, AT_SYMLINK_NOFOLLOW) >= 0)

                 return 0;

@@ -453,7 +451,7 @@ static int prompt_root_password(void) {

         if (!arg_prompt_root_password)

                 return 0;

-        etc_shadow = prefix_roota("/etc/shadow");

+        etc_shadow = prefix_roota(arg_root, "/etc/shadow");

         if (faccessat(AT_FDCWD, etc_shadow, F_OK, AT_SYMLINK_NOFOLLOW) >= 0)

                 return 0;

@@ -542,7 +540,7 @@ static int process_root_password(void) {

         const char *etc_shadow;

         int r;

-        etc_shadow = prefix_roota("/etc/shadow");

+        etc_shadow = prefix_roota(arg_root, "/etc/shadow");

         if (faccessat(AT_FDCWD, etc_shadow, F_OK, AT_SYMLINK_NOFOLLOW) >= 0)

                 return 0;

diff --git a/src/shared/cgroup-util.c b/src/shared/cgroup-util.c

index dfd8689..cf757d2 100644

--- a/src/shared/cgroup-util.c

+++ b/src/shared/cgroup-util.c

@@ -1147,7 +1147,7 @@ int cg_path_decode_unit(const char *cgroup, char **unit){

         c = strndupa(cgroup, e - cgroup);

         c = cg_unescape(c);

-        if (!unit_name_is_valid(c, TEMPLATE_INVALID))

+        if (!unit_name_is_valid(c, UNIT_NAME_PLAIN|UNIT_NAME_INSTANCE))

                 return -EINVAL;

         s = strdup(c);

@@ -1536,7 +1536,7 @@ int cg_slice_to_path(const char *unit, char **ret) {

         assert(unit);

         assert(ret);

-        if (!unit_name_is_valid(unit, TEMPLATE_INVALID))

+        if (!unit_name_is_valid(unit, UNIT_NAME_PLAIN))

                 return -EINVAL;

         if (!endswith(unit, ".slice"))

@@ -1553,7 +1553,7 @@ int cg_slice_to_path(const char *unit, char **ret) {

                 strcpy(stpncpy(n, p, dash - p), ".slice");

-                if (!unit_name_is_valid(n, TEMPLATE_INVALID))

+                if (!unit_name_is_valid(n, UNIT_NAME_PLAIN))

                         return -EINVAL;

                 escaped = cg_escape(n);

diff --git a/src/shared/install.c b/src/shared/install.c

index aa197e9..5288bb4 100644

--- a/src/shared/install.c

+++ b/src/shared/install.c

@@ -39,15 +39,24 @@

 #include "specifier.h"

 #include "install-printf.h"

 #include "special.h"

+#include "fileio.h"

+

+#define UNIT_FILE_FOLLOW_SYMLINK_MAX 64

+

+typedef enum SearchFlags {

+        SEARCH_LOAD = 1,

+        SEARCH_FOLLOW_CONFIG_SYMLINKS = 2,

+} SearchFlags;

 typedef struct {

-        OrderedHashmap *will_install;

-        OrderedHashmap *have_installed;

+        OrderedHashmap *will_process;

+        OrderedHashmap *have_processed;

 } InstallContext;

 static int in_search_path(const char *path, char **search) {

         _cleanup_free_ char *parent = NULL;

         int r;

+        char **i;

         assert(path);

@@ -55,7 +64,11 @@ static int in_search_path(const char *path, char **search) {

         if (r < 0)

                 return r;

-        return strv_contains(search, parent);

+        STRV_FOREACH(i, search)

+                if (path_equal(parent, *i))

+                        return true;

+

+        return false;

 }

 static int get_config_path(UnitFileScope scope, bool runtime, const char *root_dir, char **ret) {

@@ -66,6 +79,9 @@ static int get_config_path(UnitFileScope scope, bool runtime, const char *root_d

         assert(scope < _UNIT_FILE_SCOPE_MAX);

         assert(ret);

+        /* This determines where we shall create or remove our

+         * installation ("configuration") symlinks */

+

         switch (scope) {

         case UNIT_FILE_SYSTEM:

@@ -113,6 +129,186 @@ static int get_config_path(UnitFileScope scope, bool runtime, const char *root_d

         return 0;

 }

+static bool is_config_path(UnitFileScope scope, const char *path) {

+        int r;

+

+        assert(scope >= 0);

+        assert(scope < _UNIT_FILE_SCOPE_MAX);

+        assert(path);

+

+        /* Checks whether the specified path is intended for

+         * configuration or is outside of it */

+

+        switch (scope) {

+

+        case UNIT_FILE_SYSTEM:

+        case UNIT_FILE_GLOBAL:

+                return path_startswith(path, "/etc") ||

+                        path_startswith(path, SYSTEM_CONFIG_UNIT_PATH) ||

+                        path_startswith(path, "/run");

+

+

+        case UNIT_FILE_USER: {

+                _cleanup_free_ char *p = NULL;

+

+                r = user_config_home(&p);

+                if (r < 0)

+                        return r;

+                if (r > 0 && path_startswith(path, p))

+                        return true;

+

+                free(p);

+                p = NULL;

+

+                r = user_runtime_dir(&p);

+                if (r < 0)

+                        return r;

+                if (r > 0 && path_startswith(path, p))

+                        return true;

+

+                return false;

+        }

+

+        default:

+                assert_not_reached("Bad scope");

+        }

+}

+

+

+static int verify_root_dir(UnitFileScope scope, const char **root_dir) {

+        int r;

+

+        assert(root_dir);

+

+        /* Verifies that the specified root directory to operate on

+         * makes sense. Reset it to NULL if it is the root directory

+         * or set to empty */

+

+        if (isempty(*root_dir) || path_equal(*root_dir, "/")) {

+                *root_dir = NULL;

+                return 0;

+        }

+

+        if (scope != UNIT_FILE_SYSTEM)

+                return -EINVAL;

+

+        r = is_dir(*root_dir, true);

+        if (r < 0)

+                return r;

+        if (r == 0)

+                return -ENOTDIR;

+

+        return 0;

+}

+

+int unit_file_changes_add(

+                UnitFileChange **changes,

+                unsigned *n_changes,

+                UnitFileChangeType type,

+                const char *path,

+                const char *source) {

+

+        UnitFileChange *c;

+        unsigned i;

+

+        assert(path);

+        assert(!changes == !n_changes);

+

+        if (!changes)

+                return 0;

+

+        c = realloc(*changes, (*n_changes + 1) * sizeof(UnitFileChange));

+        if (!c)

+                return -ENOMEM;

+

+        *changes = c;

+        i = *n_changes;

+

+        c[i].type = type;

+        c[i].path = strdup(path);

+        if (!c[i].path)

+                return -ENOMEM;

+

+        path_kill_slashes(c[i].path);

+

+        if (source) {

+                c[i].source = strdup(source);

+                if (!c[i].source) {

+                        free(c[i].path);

+                        return -ENOMEM;

+                }

+

+                path_kill_slashes(c[i].path);

+        } else

+                c[i].source = NULL;

+

+        *n_changes = i+1;

+        return 0;

+}

+

+void unit_file_changes_free(UnitFileChange *changes, unsigned n_changes) {

+        unsigned i;

+

+        assert(changes || n_changes == 0);

+

+        if (!changes)

+                return;

+

+        for (i = 0; i < n_changes; i++) {

+                free(changes[i].path);

+                free(changes[i].source);

+        }

+

+        free(changes);

+}

+

+static int create_symlink(

+                const char *old_path,

+                const char *new_path,

+                bool force,

+                UnitFileChange **changes,

+                unsigned *n_changes) {

+

+        _cleanup_free_ char *dest = NULL;

+        int r;

+

+        assert(old_path);

+        assert(new_path);

+

+        /* Actually create a symlink, and remember that we did. Is

+         * smart enough to check if there's already a valid symlink in

+         * place. */

+

+        mkdir_parents_label(new_path, 0755);

+

+        if (symlink(old_path, new_path) >= 0) {

+                unit_file_changes_add(changes, n_changes, UNIT_FILE_SYMLINK, new_path, old_path);

+                return 0;

+        }

+

+        if (errno != EEXIST)

+                return -errno;

+

+        r = readlink_malloc(new_path, &dest);

+        if (r < 0)

+                return r;

+

+        if (path_equal(dest, old_path))

+                return 0;

+

+        if (!force)

+                return -EEXIST;

+

+        r = symlink_atomic(old_path, new_path);

+        if (r < 0)

+                return r;

+

+        unit_file_changes_add(changes, n_changes, UNIT_FILE_UNLINK, new_path, NULL);

+        unit_file_changes_add(changes, n_changes, UNIT_FILE_SYMLINK, new_path, old_path);

+

+        return 0;

+}

+

 static int mark_symlink_for_removal(

                 Set **remove_symlinks_to,

                 const char *p) {

@@ -136,7 +332,7 @@ static int mark_symlink_for_removal(

         if (r < 0)

                 return r == -EEXIST ? 0 : r;

-        return 0;

+        return 1;

 }

 static int remove_marked_symlinks_fd(

@@ -144,10 +340,9 @@ static int remove_marked_symlinks_fd(

                 int fd,

                 const char *path,

                 const char *config_path,

-                bool *deleted,

+                bool *restart,

                 UnitFileChange **changes,

-                unsigned *n_changes,

-                char** instance_whitelist) {

+                unsigned *n_changes) {

         _cleanup_closedir_ DIR *d = NULL;

         int r = 0;

@@ -156,7 +351,7 @@ static int remove_marked_symlinks_fd(

         assert(fd >= 0);

         assert(path);

         assert(config_path);

-        assert(deleted);

+        assert(restart);

         d = fdopendir(fd);

         if (!d) {

@@ -205,42 +400,23 @@ static int remove_marked_symlinks_fd(

                         }

                         /* This will close nfd, regardless whether it succeeds or not */

-                        q = remove_marked_symlinks_fd(remove_symlinks_to, nfd, p, config_path, deleted, changes, n_changes, instance_whitelist);

+                        q = remove_marked_symlinks_fd(remove_symlinks_to, nfd, p, config_path, restart, changes, n_changes);

                         if (q < 0 && r == 0)

                                 r = q;

                 } else if (de->d_type == DT_LNK) {

                         _cleanup_free_ char *p = NULL, *dest = NULL;

-                        int q;

                         bool found;

+                        int q;

-                        if (!unit_name_is_valid(de->d_name, TEMPLATE_VALID))

+                        if (!unit_name_is_valid(de->d_name, UNIT_NAME_ANY))

                                 continue;

-                        if (unit_name_is_instance(de->d_name) &&

-                            instance_whitelist &&

-                            !strv_contains(instance_whitelist, de->d_name)) {

-

-                                _cleanup_free_ char *w;

-

-                                /* OK, the file is not listed directly

-                                 * in the whitelist, so let's check if

-                                 * the template of it might be

-                                 * listed. */

-

-                                w = unit_name_template(de->d_name);

-                                if (!w)

-                                        return -ENOMEM;

-

-                                if (!strv_contains(instance_whitelist, w))

-                                        continue;

-                        }

-

                         p = path_make_absolute(de->d_name, path);

                         if (!p)

                                 return -ENOMEM;

-                        q = readlink_and_canonicalize(p, &dest);

+                        q = readlink_malloc(p, &dest);

                         if (q < 0) {

                                 if (q == -ENOENT)