Adding upstream version 255.4.upstream/255.4

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 678 insertions, 0 deletions

diff --git a/src/libsystemd/sd-device/test-sd-device.c b/src/libsystemd/sd-device/test-sd-device.c
new file mode 100644
index 0000000..bce99b5
--- /dev/null
+++ b/src/libsystemd/sd-device/test-sd-device.c
@@ -0,0 +1,678 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <ctype.h>
+#include <fcntl.h>
+#include <unistd.h>
+
+#include "device-enumerator-private.h"
+#include "device-internal.h"
+#include "device-private.h"
+#include "device-util.h"
+#include "errno-util.h"
+#include "fd-util.h"
+#include "hashmap.h"
+#include "nulstr-util.h"
+#include "path-util.h"
+#include "rm-rf.h"
+#include "stat-util.h"
+#include "string-util.h"
+#include "tests.h"
+#include "time-util.h"
+#include "tmpfile-util.h"
+#include "udev-util.h"
+
+static void test_sd_device_one(sd_device *d) {
+        _cleanup_(sd_device_unrefp) sd_device *dev = NULL;
+        const char *syspath, *sysname, *subsystem = NULL, *devname, *val;
+        bool is_block = false;
+        dev_t devnum;
+        usec_t usec;
+        int ifindex, r;
+
+        assert_se(sd_device_get_syspath(d, &syspath) >= 0);
+        assert_se(path_startswith(syspath, "/sys"));
+        assert_se(sd_device_get_sysname(d, &sysname) >= 0);
+
+        log_info("%s(%s)", __func__, syspath);
+
+        assert_se(sd_device_new_from_syspath(&dev, syspath) >= 0);
+        assert_se(sd_device_get_syspath(dev, &val) >= 0);
+        assert_se(streq(syspath, val));
+        dev = sd_device_unref(dev);
+
+        assert_se(sd_device_new_from_path(&dev, syspath) >= 0);
+        assert_se(sd_device_get_syspath(dev, &val) >= 0);
+        assert_se(streq(syspath, val));
+        dev = sd_device_unref(dev);
+
+        r = sd_device_get_ifindex(d, &ifindex);
+        if (r >= 0) {
+                assert_se(ifindex > 0);
+
+                r = sd_device_new_from_ifindex(&dev, ifindex);
+                if (r == -ENODEV)
+                        log_device_warning_errno(d, r,
+                                                 "Failed to create sd-device object from ifindex %i. "
+                                                 "Maybe running on a non-host network namespace.", ifindex);
+                else {
+                        assert_se(r >= 0);
+                        assert_se(sd_device_get_syspath(dev, &val) >= 0);
+                        assert_se(streq(syspath, val));
+                        dev = sd_device_unref(dev);
+                }
+
+                /* This does not require the interface really exists on the network namespace.
+                 * Hence, this should always succeed. */
+                assert_se(sd_device_new_from_ifname(&dev, sysname) >= 0);
+                assert_se(sd_device_get_syspath(dev, &val) >= 0);
+                assert_se(streq(syspath, val));
+                dev = sd_device_unref(dev);
+        } else
+                assert_se(r == -ENOENT);
+
+        r = sd_device_get_subsystem(d, &subsystem);
+        if (r < 0)
+                assert_se(r == -ENOENT);
+        else if (!streq(subsystem, "gpio")) { /* Unfortunately, there exist /sys/class/gpio and /sys/bus/gpio.
+                                               * Hence, sd_device_new_from_subsystem_sysname() and
+                                               * sd_device_new_from_device_id() may not work as expected. */
+                const char *name, *id;
+
+                if (streq(subsystem, "drivers"))
+                        name = strjoina(d->driver_subsystem, ":", sysname);
+                else
+                        name = sysname;
+                assert_se(sd_device_new_from_subsystem_sysname(&dev, subsystem, name) >= 0);
+                assert_se(sd_device_get_syspath(dev, &val) >= 0);
+                assert_se(streq(syspath, val));
+                dev = sd_device_unref(dev);
+
+                /* The device ID depends on subsystem. */
+                assert_se(device_get_device_id(d, &id) >= 0);
+                r = sd_device_new_from_device_id(&dev, id);
+                if (r == -ENODEV && ifindex > 0)
+                        log_device_warning_errno(d, r,
+                                                 "Failed to create sd-device object from device ID \"%s\". "
+                                                 "Maybe running on a non-host network namespace.", id);
+                else {
+                        assert_se(r >= 0);
+                        assert_se(sd_device_get_syspath(dev, &val) >= 0);
+                        assert_se(streq(syspath, val));
+                        dev = sd_device_unref(dev);
+                }
+
+                /* These require udev database, and reading database requires device ID. */
+                r = sd_device_get_is_initialized(d);
+                if (r > 0) {
+                        r = sd_device_get_usec_since_initialized(d, &usec);
+                        assert_se((r >= 0 && usec > 0) || r == -ENODATA);
+                } else
+                        assert(r == 0);
+
+                r = sd_device_get_property_value(d, "ID_NET_DRIVER", &val);
+                assert_se(r >= 0 || r == -ENOENT);
+        }
+
+        is_block = streq_ptr(subsystem, "block");
+
+        r = sd_device_get_devname(d, &devname);
+        if (r >= 0) {
+                r = sd_device_new_from_devname(&dev, devname);
+                if (r >= 0) {
+                        assert_se(sd_device_get_syspath(dev, &val) >= 0);
+                        assert_se(streq(syspath, val));
+                        dev = sd_device_unref(dev);
+                } else
+                        assert_se(r == -ENODEV || ERRNO_IS_PRIVILEGE(r));
+
+                r = sd_device_new_from_path(&dev, devname);
+                if (r >= 0) {
+                        assert_se(sd_device_get_syspath(dev, &val) >= 0);
+                        assert_se(streq(syspath, val));
+                        dev = sd_device_unref(dev);
+
+                        _cleanup_close_ int fd = -EBADF;
+                        fd = sd_device_open(d, O_CLOEXEC| O_NONBLOCK | (is_block ? O_RDONLY : O_NOCTTY | O_PATH));
+                        assert_se(fd >= 0 || ERRNO_IS_PRIVILEGE(fd));
+                } else
+                        assert_se(r == -ENODEV || ERRNO_IS_PRIVILEGE(r));
+        } else
+                assert_se(r == -ENOENT);
+
+        r = sd_device_get_devnum(d, &devnum);
+        if (r >= 0) {
+                _cleanup_free_ char *p = NULL;
+
+                assert_se(major(devnum) > 0);
+
+                assert_se(sd_device_new_from_devnum(&dev, is_block ? 'b' : 'c', devnum) >= 0);
+                assert_se(sd_device_get_syspath(dev, &val) >= 0);
+                assert_se(streq(syspath, val));
+                dev = sd_device_unref(dev);
+
+                assert_se(asprintf(&p, "/dev/%s/%u:%u", is_block ? "block" : "char", major(devnum), minor(devnum)) >= 0);
+                assert_se(sd_device_new_from_devname(&dev, p) >= 0);
+                assert_se(sd_device_get_syspath(dev, &val) >= 0);
+                assert_se(streq(syspath, val));
+                dev = sd_device_unref(dev);
+
+                assert_se(sd_device_new_from_path(&dev, p) >= 0);
+                assert_se(sd_device_get_syspath(dev, &val) >= 0);
+                assert_se(streq(syspath, val));
+                dev = sd_device_unref(dev);
+        } else
+                assert_se(r == -ENOENT);
+
+        assert_se(sd_device_get_devpath(d, &val) >= 0);
+
+        r = sd_device_get_devtype(d, &val);
+        assert_se(r >= 0 || r == -ENOENT);
+
+        r = sd_device_get_driver(d, &val);
+        assert_se(r >= 0 || r == -ENOENT);
+
+        r = sd_device_get_sysnum(d, &val);
+        if (r >= 0) {
+                assert_se(val > sysname);
+                assert_se(val < sysname + strlen(sysname));
+                assert_se(in_charset(val, DIGITS));
+                assert_se(!ascii_isdigit(val[-1]));
+        } else
+                assert_se(r == -ENOENT);
+
+        r = sd_device_get_sysattr_value(d, "nsid", NULL);
+        if (r >= 0) {
+                unsigned x;
+
+                assert_se(device_get_sysattr_unsigned(d, "nsid", NULL) >= 0);
+                r = device_get_sysattr_unsigned(d, "nsid", &x);
+                assert_se(r >= 0);
+                assert_se((x > 0) == (r > 0));
+        } else
+                assert_se(ERRNO_IS_PRIVILEGE(r) || IN_SET(r, -ENOENT, -EINVAL));
+}
+
+TEST(sd_device_enumerator_devices) {
+        _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL;
+
+        assert_se(sd_device_enumerator_new(&e) >= 0);
+        assert_se(sd_device_enumerator_allow_uninitialized(e) >= 0);
+        /* On some CI environments, it seems some loop block devices and corresponding bdi devices sometimes
+         * disappear during running this test. Let's exclude them here for stability. */
+        assert_se(sd_device_enumerator_add_match_subsystem(e, "bdi", false) >= 0);
+        assert_se(sd_device_enumerator_add_nomatch_sysname(e, "loop*") >= 0);
+        /* On CentOS CI, systemd-networkd-tests.py may be running when this test is invoked. The networkd
+         * test creates and removes many network interfaces, and may interfere with this test. */
+        assert_se(sd_device_enumerator_add_match_subsystem(e, "net", false) >= 0);
+        FOREACH_DEVICE(e, d)
+                test_sd_device_one(d);
+}
+
+TEST(sd_device_enumerator_subsystems) {
+        _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL;
+
+        assert_se(sd_device_enumerator_new(&e) >= 0);
+        assert_se(sd_device_enumerator_allow_uninitialized(e) >= 0);
+        FOREACH_SUBSYSTEM(e, d)
+                test_sd_device_one(d);
+}
+
+static void test_sd_device_enumerator_filter_subsystem_one(
+                const char *subsystem,
+                Hashmap *h,
+                unsigned *ret_n_new_dev,
+                unsigned *ret_n_removed_dev) {
+
+        _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL;
+        unsigned n_new_dev = 0, n_removed_dev = 0;
+        sd_device *dev;
+
+        assert_se(sd_device_enumerator_new(&e) >= 0);
+        assert_se(sd_device_enumerator_add_match_subsystem(e, subsystem, true) >= 0);
+        assert_se(sd_device_enumerator_add_nomatch_sysname(e, "loop*") >= 0);
+
+        FOREACH_DEVICE(e, d) {
+                const char *syspath;
+                sd_device *t;
+
+                assert_se(sd_device_get_syspath(d, &syspath) >= 0);
+                t = hashmap_remove(h, syspath);
+
+                if (!t) {
+                        log_warning("New device found: subsystem:%s syspath:%s", subsystem, syspath);
+                        n_new_dev++;
+                }
+
+                assert_se(!sd_device_unref(t));
+        }
+
+        HASHMAP_FOREACH(dev, h) {
+                const char *syspath;
+
+                assert_se(sd_device_get_syspath(dev, &syspath) >= 0);
+                log_warning("Device removed: subsystem:%s syspath:%s", subsystem, syspath);
+                n_removed_dev++;
+
+                assert_se(!sd_device_unref(dev));
+        }
+
+        hashmap_free(h);
+
+        *ret_n_new_dev = n_new_dev;
+        *ret_n_removed_dev = n_removed_dev;
+}
+
+static bool test_sd_device_enumerator_filter_subsystem_trial(void) {
+        _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL;
+        _cleanup_hashmap_free_ Hashmap *subsystems = NULL;
+        unsigned n_new_dev = 0, n_removed_dev = 0;
+        Hashmap *h;
+        char *s;
+
+        assert_se(subsystems = hashmap_new(&string_hash_ops));
+        assert_se(sd_device_enumerator_new(&e) >= 0);
+        /* See comments in TEST(sd_device_enumerator_devices). */
+        assert_se(sd_device_enumerator_add_match_subsystem(e, "bdi", false) >= 0);
+        assert_se(sd_device_enumerator_add_nomatch_sysname(e, "loop*") >= 0);
+        assert_se(sd_device_enumerator_add_match_subsystem(e, "net", false) >= 0);
+
+        FOREACH_DEVICE(e, d) {
+                const char *syspath, *subsystem;
+                int r;
+
+                assert_se(sd_device_get_syspath(d, &syspath) >= 0);
+
+                r = sd_device_get_subsystem(d, &subsystem);
+                assert_se(r >= 0 || r == -ENOENT);
+                if (r < 0)
+                        continue;
+
+                h = hashmap_get(subsystems, subsystem);
+                if (!h) {
+                        char *str;
+                        assert_se(str = strdup(subsystem));
+                        assert_se(h = hashmap_new(&string_hash_ops));
+                        assert_se(hashmap_put(subsystems, str, h) >= 0);
+                }
+
+                assert_se(hashmap_put(h, syspath, d) >= 0);
+                assert_se(sd_device_ref(d));
+
+                log_debug("Added subsystem:%s syspath:%s", subsystem, syspath);
+        }
+
+        while ((h = hashmap_steal_first_key_and_value(subsystems, (void**) &s))) {
+                unsigned n, m;
+
+                test_sd_device_enumerator_filter_subsystem_one(s, TAKE_PTR(h), &n, &m);
+                free(s);
+
+                n_new_dev += n;
+                n_removed_dev += m;
+        }
+
+        if (n_new_dev > 0)
+                log_warning("%u new devices are found in re-scan", n_new_dev);
+        if (n_removed_dev > 0)
+                log_warning("%u devices removed in re-scan", n_removed_dev);
+
+        return n_new_dev + n_removed_dev == 0;
+}
+
+static bool test_sd_device_enumerator_filter_subsystem_trial_many(void) {
+        for (unsigned i = 0; i < 20; i++) {
+                log_debug("%s(): trial %u", __func__, i);
+                if (test_sd_device_enumerator_filter_subsystem_trial())
+                        return true;
+        }
+
+        return false;
+}
+
+static int on_inotify(sd_event_source *s, const struct inotify_event *event, void *userdata) {
+        if (test_sd_device_enumerator_filter_subsystem_trial_many())
+                return sd_event_exit(sd_event_source_get_event(s), 0);
+
+        return sd_event_exit(sd_event_source_get_event(s), -EBUSY);
+}
+
+TEST(sd_device_enumerator_filter_subsystem) {
+        /* The test test_sd_device_enumerator_filter_subsystem_trial() is quite racy. Let's run the function
+         * several times after the udev queue becomes empty. */
+
+        if (!udev_available() || (access("/run/udev", F_OK) < 0 && errno == ENOENT)) {
+                assert_se(test_sd_device_enumerator_filter_subsystem_trial_many());
+                return;
+        }
+
+        _cleanup_(sd_event_unrefp) sd_event *event = NULL;
+        assert_se(sd_event_default(&event) >= 0);
+        assert_se(sd_event_add_inotify(event, NULL, "/run/udev" , IN_DELETE, on_inotify, NULL) >= 0);
+
+        if (udev_queue_is_empty() == 0) {
+                log_debug("udev queue is not empty, waiting for all queued events to be processed.");
+                assert_se(sd_event_loop(event) >= 0);
+        } else
+                assert_se(test_sd_device_enumerator_filter_subsystem_trial_many());
+}
+
+TEST(sd_device_enumerator_add_match_sysattr) {
+        _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL;
+        sd_device *dev;
+        int ifindex;
+
+        assert_se(sd_device_enumerator_new(&e) >= 0);
+        assert_se(sd_device_enumerator_allow_uninitialized(e) >= 0);
+        assert_se(sd_device_enumerator_add_match_subsystem(e, "net", true) >= 0);
+        assert_se(sd_device_enumerator_add_match_sysattr(e, "ifindex", "1", true) >= 0);
+        assert_se(sd_device_enumerator_add_match_sysattr(e, "ifindex", "hoge", true) >= 0);
+        assert_se(sd_device_enumerator_add_match_sysattr(e, "ifindex", "foo", true) >= 0);
+        assert_se(sd_device_enumerator_add_match_sysattr(e, "ifindex", "bar", false) >= 0);
+        assert_se(sd_device_enumerator_add_match_sysattr(e, "ifindex", "baz", false) >= 0);
+
+        dev = sd_device_enumerator_get_device_first(e);
+        assert_se(dev);
+        assert_se(sd_device_get_ifindex(dev, &ifindex) >= 0);
+        assert_se(ifindex == 1);
+
+        assert_se(!sd_device_enumerator_get_device_next(e));
+}
+
+TEST(sd_device_enumerator_add_match_property) {
+        _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL;
+        sd_device *dev;
+        int ifindex;
+
+        assert_se(sd_device_enumerator_new(&e) >= 0);
+        assert_se(sd_device_enumerator_allow_uninitialized(e) >= 0);
+        assert_se(sd_device_enumerator_add_match_subsystem(e, "net", true) >= 0);
+        assert_se(sd_device_enumerator_add_match_sysattr(e, "ifindex", "1", true) >= 0);
+        assert_se(sd_device_enumerator_add_match_property(e, "IFINDE*", "1*") >= 0);
+        assert_se(sd_device_enumerator_add_match_property(e, "IFINDE*", "hoge") >= 0);
+        assert_se(sd_device_enumerator_add_match_property(e, "IFINDE*", NULL) >= 0);
+        assert_se(sd_device_enumerator_add_match_property(e, "AAAAA", "BBBB") >= 0);
+        assert_se(sd_device_enumerator_add_match_property(e, "FOOOO", NULL) >= 0);
+
+        dev = sd_device_enumerator_get_device_first(e);
+        assert_se(dev);
+        assert_se(sd_device_get_ifindex(dev, &ifindex) >= 0);
+        assert_se(ifindex == 1);
+}
+
+TEST(sd_device_enumerator_add_match_property_required) {
+        _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL;
+        sd_device *dev;
+        int ifindex;
+
+        assert_se(sd_device_enumerator_new(&e) >= 0);
+        assert_se(sd_device_enumerator_allow_uninitialized(e) >= 0);
+        assert_se(sd_device_enumerator_add_match_subsystem(e, "net", true) >= 0);
+        assert_se(sd_device_enumerator_add_match_sysattr(e, "ifindex", "1", true) >= 0);
+        assert_se(sd_device_enumerator_add_match_property_required(e, "IFINDE*", "1*") >= 0);
+
+        /* Only one required match which should be satisfied. */
+        dev = sd_device_enumerator_get_device_first(e);
+        assert_se(dev);
+        assert_se(sd_device_get_ifindex(dev, &ifindex) >= 0);
+        assert_se(ifindex == 1);
+
+        /* Now let's add a bunch of garbage properties which should not be satisfied. */
+        assert_se(sd_device_enumerator_add_match_property_required(e, "IFINDE*", "hoge") >= 0);
+        assert_se(sd_device_enumerator_add_match_property_required(e, "IFINDE*", NULL) >= 0);
+        assert_se(sd_device_enumerator_add_match_property_required(e, "AAAAA", "BBBB") >= 0);
+        assert_se(sd_device_enumerator_add_match_property_required(e, "FOOOO", NULL) >= 0);
+
+        assert_se(!sd_device_enumerator_get_device_first(e));
+}
+
+static void check_parent_match(sd_device_enumerator *e, sd_device *dev) {
+        const char *syspath;
+        bool found = false;
+
+        assert_se(sd_device_get_syspath(dev, &syspath) >= 0);
+
+        FOREACH_DEVICE(e, d) {
+                const char *s;
+
+                assert_se(sd_device_get_syspath(d, &s) >= 0);
+                if (streq(s, syspath)) {
+                        found = true;
+                        break;
+                }
+        }
+
+        if (!found) {
+                log_device_debug(dev, "not enumerated, already removed??");
+                /* If the original device not found, then the device should be already removed. */
+                assert_se(access(syspath, F_OK) < 0);
+                assert_se(errno == ENOENT);
+        }
+}
+
+TEST(sd_device_enumerator_add_match_parent) {
+        _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL;
+        int r;
+
+        assert_se(sd_device_enumerator_new(&e) >= 0);
+        assert_se(sd_device_enumerator_allow_uninitialized(e) >= 0);
+        /* See comments in TEST(sd_device_enumerator_devices). */
+        assert_se(sd_device_enumerator_add_match_subsystem(e, "bdi", false) >= 0);
+        assert_se(sd_device_enumerator_add_nomatch_sysname(e, "loop*") >= 0);
+        assert_se(sd_device_enumerator_add_match_subsystem(e, "net", false) >= 0);
+
+        if (!slow_tests_enabled())
+                assert_se(sd_device_enumerator_add_match_subsystem(e, "block", true) >= 0);
+
+        FOREACH_DEVICE(e, dev) {
+                _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *p = NULL;
+                const char *syspath;
+                sd_device *parent;
+
+                assert_se(sd_device_get_syspath(dev, &syspath) >= 0);
+
+                r = sd_device_get_parent(dev, &parent);
+                if (r < 0) {
+                        assert_se(ERRNO_IS_DEVICE_ABSENT(r));
+                        continue;
+                }
+
+                log_debug("> %s", syspath);
+
+                assert_se(sd_device_enumerator_new(&p) >= 0);
+                assert_se(sd_device_enumerator_allow_uninitialized(p) >= 0);
+                assert_se(sd_device_enumerator_add_match_parent(p, parent) >= 0);
+
+                check_parent_match(p, dev);
+
+                /* If the device does not have subsystem, then it is not enumerated. */
+                r = sd_device_get_subsystem(parent, NULL);
+                if (r < 0) {
+                        assert_se(r == -ENOENT);
+                        continue;
+                }
+                check_parent_match(p, parent);
+        }
+}
+
+TEST(sd_device_get_child) {
+        _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL;
+        int r;
+
+        assert_se(sd_device_enumerator_new(&e) >= 0);
+        assert_se(sd_device_enumerator_allow_uninitialized(e) >= 0);
+        /* See comments in TEST(sd_device_enumerator_devices). */
+        assert_se(sd_device_enumerator_add_match_subsystem(e, "bdi", false) >= 0);
+        assert_se(sd_device_enumerator_add_nomatch_sysname(e, "loop*") >= 0);
+        assert_se(sd_device_enumerator_add_match_subsystem(e, "net", false) >= 0);
+
+        if (!slow_tests_enabled())
+                assert_se(sd_device_enumerator_add_match_subsystem(e, "block", true) >= 0);
+
+        FOREACH_DEVICE(e, dev) {
+                const char *syspath, *parent_syspath, *expected_suffix, *suffix;
+                sd_device *parent;
+                bool found = false;
+
+                assert_se(sd_device_get_syspath(dev, &syspath) >= 0);
+
+                r = sd_device_get_parent(dev, &parent);
+                if (r < 0) {
+                        assert_se(ERRNO_IS_DEVICE_ABSENT(r));
+                        continue;
+                }
+
+                assert_se(sd_device_get_syspath(parent, &parent_syspath) >= 0);
+                assert_se(expected_suffix = path_startswith(syspath, parent_syspath));
+
+                log_debug("> %s", syspath);
+
+                FOREACH_DEVICE_CHILD_WITH_SUFFIX(parent, child, suffix) {
+                        const char *s;
+
+                        assert_se(child);
+                        assert_se(suffix);
+
+                        if (!streq(suffix, expected_suffix))
+                                continue;
+
+                        assert_se(sd_device_get_syspath(child, &s) >= 0);
+                        assert_se(streq(s, syspath));
+                        found = true;
+                        break;
+                }
+                assert_se(found);
+        }
+}
+
+TEST(sd_device_new_from_nulstr) {
+        const char *devlinks =
+                "/dev/disk/by-partuuid/1290d63a-42cc-4c71-b87c-xxxxxxxxxxxx\0"
+                "/dev/disk/by-path/pci-0000:00:0f.0-scsi-0:0:0:0-part3\0"
+                "/dev/disk/by-label/Arch\\x20Linux\0"
+                "/dev/disk/by-uuid/a07b87e5-4af5-4a59-bde9-yyyyyyyyyyyy\0"
+                "/dev/disk/by-partlabel/Arch\\x20Linux\0"
+                "\0";
+
+        _cleanup_(sd_device_unrefp) sd_device *device = NULL, *from_nulstr = NULL;
+        _cleanup_free_ char *nulstr_copy = NULL;
+        const char *nulstr;
+        size_t len;
+
+        assert_se(sd_device_new_from_syspath(&device, "/sys/class/net/lo") >= 0);
+
+        /* Yeah, of course, setting devlink to the loopback interface is nonsense. But this is just a
+         * test for generating and parsing nulstr. For issue #17772. */
+        NULSTR_FOREACH(devlink, devlinks) {
+                log_device_info(device, "setting devlink: %s", devlink);
+                assert_se(device_add_devlink(device, devlink) >= 0);
+                assert_se(set_contains(device->devlinks, devlink));
+        }
+
+        /* For issue #23799 */
+        assert_se(device_add_tag(device, "tag1", false) >= 0);
+        assert_se(device_add_tag(device, "tag2", false) >= 0);
+        assert_se(device_add_tag(device, "current-tag1", true) >= 0);
+        assert_se(device_add_tag(device, "current-tag2", true) >= 0);
+
+        /* These properties are necessary for device_new_from_nulstr(). See device_verify(). */
+        assert_se(device_add_property_internal(device, "SEQNUM", "1") >= 0);
+        assert_se(device_add_property_internal(device, "ACTION", "change") >= 0);
+
+        assert_se(device_get_properties_nulstr(device, &nulstr, &len) >= 0);
+        assert_se(nulstr_copy = newdup(char, nulstr, len));
+        assert_se(device_new_from_nulstr(&from_nulstr, nulstr_copy, len) >= 0);
+
+        assert_se(sd_device_has_tag(from_nulstr, "tag1") == 1);
+        assert_se(sd_device_has_tag(from_nulstr, "tag2") == 1);
+        assert_se(sd_device_has_tag(from_nulstr, "current-tag1") == 1);
+        assert_se(sd_device_has_tag(from_nulstr, "current-tag2") == 1);
+        assert_se(sd_device_has_current_tag(from_nulstr, "tag1") == 0);
+        assert_se(sd_device_has_current_tag(from_nulstr, "tag2") == 0);
+        assert_se(sd_device_has_current_tag(from_nulstr, "current-tag1") == 1);
+        assert_se(sd_device_has_current_tag(from_nulstr, "current-tag2") == 1);
+
+        NULSTR_FOREACH(devlink, devlinks) {
+                log_device_info(from_nulstr, "checking devlink: %s", devlink);
+                assert_se(set_contains(from_nulstr->devlinks, devlink));
+        }
+}
+
+TEST(sd_device_new_from_path) {
+        _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL;
+        _cleanup_(rm_rf_physical_and_freep) char *tmpdir = NULL;
+        int r;
+
+        assert_se(mkdtemp_malloc("/tmp/test-sd-device.XXXXXXX", &tmpdir) >= 0);
+
+        assert_se(sd_device_enumerator_new(&e) >= 0);
+        assert_se(sd_device_enumerator_allow_uninitialized(e) >= 0);
+        assert_se(sd_device_enumerator_add_match_subsystem(e, "block", true) >= 0);
+        assert_se(sd_device_enumerator_add_nomatch_sysname(e, "loop*") >= 0);
+        assert_se(sd_device_enumerator_add_match_property(e, "DEVNAME", "*") >= 0);
+
+        FOREACH_DEVICE(e, dev) {
+                _cleanup_(sd_device_unrefp) sd_device *d = NULL;
+                const char *syspath, *devpath, *sysname, *s;
+                _cleanup_free_ char *path = NULL;
+
+                assert_se(sd_device_get_sysname(dev, &sysname) >= 0);
+
+                log_debug("%s(%s)", __func__, sysname);
+
+                assert_se(sd_device_get_syspath(dev, &syspath) >= 0);
+                assert_se(sd_device_new_from_path(&d, syspath) >= 0);
+                assert_se(sd_device_get_syspath(d, &s) >= 0);
+                assert_se(streq(s, syspath));
+                d = sd_device_unref(d);
+
+                assert_se(sd_device_get_devname(dev, &devpath) >= 0);
+                r = sd_device_new_from_path(&d, devpath);
+                if (r >= 0) {
+                        assert_se(sd_device_get_syspath(d, &s) >= 0);
+                        assert_se(streq(s, syspath));
+                        d = sd_device_unref(d);
+                } else
+                        assert_se(r == -ENODEV || ERRNO_IS_PRIVILEGE(r));
+
+                assert_se(path = path_join(tmpdir, sysname));
+                assert_se(symlink(syspath, path) >= 0);
+                assert_se(sd_device_new_from_path(&d, path) >= 0);
+                assert_se(sd_device_get_syspath(d, &s) >= 0);
+                assert_se(streq(s, syspath));
+        }
+}
+
+static void test_devname_from_devnum_one(const char *path) {
+        _cleanup_free_ char *resolved = NULL;
+        struct stat st;
+
+        log_debug("> %s", path);
+
+        if (stat(path, &st) < 0) {
+                assert_se(errno == ENOENT);
+                log_notice("Path %s not found, skipping test", path);
+                return;
+        }
+
+        assert_se(devname_from_devnum(st.st_mode, st.st_rdev, &resolved) >= 0);
+        assert_se(path_equal(path, resolved));
+        resolved = mfree(resolved);
+        assert_se(devname_from_stat_rdev(&st, &resolved) >= 0);
+        assert_se(path_equal(path, resolved));
+}
+
+TEST(devname_from_devnum) {
+        test_devname_from_devnum_one("/dev/null");
+        test_devname_from_devnum_one("/dev/zero");
+        test_devname_from_devnum_one("/dev/full");
+        test_devname_from_devnum_one("/dev/random");
+        test_devname_from_devnum_one("/dev/urandom");
+        test_devname_from_devnum_one("/dev/tty");
+
+        if (is_device_node("/run/systemd/inaccessible/blk") > 0) {
+                test_devname_from_devnum_one("/run/systemd/inaccessible/chr");
+                test_devname_from_devnum_one("/run/systemd/inaccessible/blk");
+        }
+}
+
+DEFINE_TEST_MAIN(LOG_INFO);