test: fix a yet another pipefail + pipe race

Basically the same scenario as in
a33e2692e162671f0d97856ad2f49a2620a1ec10, where `awk` exits as soon
as it finds a match, thus sending SIGPIPE to `ldd` if it's not fast
enough. That, in combination with `set -o pipefail` causes random &
unexpected fails, like:

```
No journal files were found.
-rw-r----- 1 root root 16777216 Apr 30 10:31
/var/tmp/TEST-01-BASIC_sanitizers-nspawn/system.journal
TEST-01-BASIC RUN: Basic systemd setup [OK]
systemd is not linked against the ASan DSO
gcc does this by default, for clang compile with -shared-libasan
make: *** [Makefile:2: clean-again] Error 1
make: Leaving directory '/build/test/TEST-01-BASIC'
```

src/libsystemd/sd-device/device-internal.h

@@ -67,7 +67,7 @@ struct sd_device {
         char *driver_subsystem; /* only set for the 'drivers' subsystem */
         char *driver;
 
-        char *id_filename;
+        char *device_id;
 
         usec_t usec_initialized;
 
@@ -84,9 +84,7 @@ struct sd_device {
         bool property_tags_outdated:1; /* need to update TAGS= or CURRENT_TAGS= property */
         bool property_devlinks_outdated:1; /* need to update DEVLINKS= property */
         bool properties_buf_outdated:1; /* need to reread hashmap */
-        bool sysname_set:1; /* don't reread sysname */
         bool subsystem_set:1; /* don't reread subsystem */
-        bool driver_subsystem_set:1; /* don't reread subsystem */
         bool driver_set:1; /* don't reread driver */
         bool uevent_loaded:1; /* don't reread uevent */
         bool db_loaded; /* don't reread db */

src/libsystemd/sd-device/device-private.c

@@ -20,6 +20,7 @@
 #include "parse-util.h"
 #include "path-util.h"
 #include "set.h"
+#include "stdio-util.h"
 #include "string-table.h"
 #include "string-util.h"
 #include "strv.h"
@@ -568,28 +569,142 @@ int device_get_devlink_priority(sd_device *device, int *priority) {
         return 0;
 }
 
-int device_get_watch_handle(sd_device *device, int *handle) {
+int device_get_watch_handle(sd_device *device) {
+        char path_wd[STRLEN("/run/udev/watch/") + DECIMAL_STR_MAX(int)];
+        _cleanup_free_ char *buf = NULL;
+        const char *id, *path_id;
+        int wd, r;
+
+        assert(device);
+
+        if (device->watch_handle >= 0)
+                return device->watch_handle;
+
+        r = device_get_device_id(device, &id);
+        if (r < 0)
+                return r;
+
+        path_id = strjoina("/run/udev/watch/", id);
+        r = readlink_malloc(path_id, &buf);
+        if (r < 0)
+                return r;
+
+        r = safe_atoi(buf, &wd);
+        if (r < 0)
+                return r;
+
+        if (wd < 0)
+                return -EBADF;
+
+        buf = mfree(buf);
+        xsprintf(path_wd, "/run/udev/watch/%d", wd);
+        r = readlink_malloc(path_wd, &buf);
+        if (r < 0)
+                return r;
+
+        if (!streq(buf, id))
+                return -EBADF;
+
+        return device->watch_handle = wd;
+}
+
+static void device_remove_watch_handle(sd_device *device) {
+        const char *id;
+        int wd;
+
+        assert(device);
+
+        /* First, remove the symlink from handle to device id. */
+        wd = device_get_watch_handle(device);
+        if (wd >= 0) {
+                char path_wd[STRLEN("/run/udev/watch/") + DECIMAL_STR_MAX(int)];
+
+                xsprintf(path_wd, "/run/udev/watch/%d", wd);
+                if (unlink(path_wd) < 0 && errno != ENOENT)
+                        log_device_debug_errno(device, errno,
+                                               "sd-device: failed to remove %s, ignoring: %m",
+                                               path_wd);
+        }
+
+        /* Next, remove the symlink from device id to handle. */
+        if (device_get_device_id(device, &id) >= 0) {
+                const char *path_id;
+
+                path_id = strjoina("/run/udev/watch/", id);
+                if (unlink(path_id) < 0 && errno != ENOENT)
+                        log_device_debug_errno(device, errno,
+                                               "sd-device: failed to remove %s, ignoring: %m",
+                                               path_id);
+        }
+
+        device->watch_handle = -1;
+}
+
+int device_set_watch_handle(sd_device *device, int wd) {
+        char path_wd[STRLEN("/run/udev/watch/") + DECIMAL_STR_MAX(int)];
+        const char *id, *path_id;
         int r;
 
         assert(device);
 
-        r = device_read_db(device);
+        if (wd >= 0 && wd == device->watch_handle)
+                return 0;
+
+        device_remove_watch_handle(device);
+
+        if (wd < 0)
+                /* negative wd means that the caller requests to clear saved watch handle. */
+                return 0;
+
+        r = device_get_device_id(device, &id);
         if (r < 0)
                 return r;
 
-        if (device->watch_handle < 0)
+        path_id = strjoina("/run/udev/watch/", id);
-                return -ENOENT;
+        xsprintf(path_wd, "/run/udev/watch/%d", wd);
 
-        if (handle)
+        r = mkdir_parents(path_wd, 0755);
-                *handle = device->watch_handle;
+        if (r < 0)
+                return r;
+
+        if (symlink(id, path_wd) < 0)
+                return -errno;
+
+        if (symlink(path_wd + STRLEN("/run/udev/watch/"), path_id) < 0) {
+                r = -errno;
+                if (unlink(path_wd) < 0 && errno != ENOENT)
+                        log_device_debug_errno(device, errno,
+                                               "sd-device: failed to remove %s, ignoring: %m",
+                                               path_wd);
+                return r;
+        }
+
+        device->watch_handle = wd;
 
         return 0;
 }
 
-void device_set_watch_handle(sd_device *device, int handle) {
+int device_new_from_watch_handle_at(sd_device **ret, int dirfd, int wd) {
-        assert(device);
+        char path_wd[STRLEN("/run/udev/watch/") + DECIMAL_STR_MAX(int)];
+        _cleanup_free_ char *id = NULL;
+        int r;
 
-        device->watch_handle = handle;
+        assert(ret);
+
+        if (wd < 0)
+                return -EBADF;
+
+        if (dirfd >= 0) {
+                xsprintf(path_wd, "%d", wd);
+                r = readlinkat_malloc(dirfd, path_wd, &id);
+        } else {
+                xsprintf(path_wd, "/run/udev/watch/%d", wd);
+                r = readlink_malloc(path_wd, &id);
+        }
+        if (r < 0)
+                return r;
+
+        return sd_device_new_from_device_id(ret, id);
 }
 
 int device_rename(sd_device *device, const char *name) {
@@ -761,7 +876,7 @@ static int device_tag(sd_device *device, const char *tag, bool add) {
         assert(device);
         assert(tag);
 
-        r = device_get_id_filename(device, &id);
+        r = device_get_device_id(device, &id);
         if (r < 0)
                 return r;
 
@@ -822,9 +937,6 @@ static bool device_has_info(sd_device *device) {
         if (!set_isempty(device->current_tags))
                 return true;
 
-        if (device->watch_handle >= 0)
-                return true;
-
         return false;
 }
 
@@ -846,7 +958,7 @@ int device_update_db(sd_device *device) {
 
         has_info = device_has_info(device);
 
-        r = device_get_id_filename(device, &id);
+        r = device_get_device_id(device, &id);
         if (r < 0)
                 return r;
 
@@ -899,9 +1011,6 @@ int device_update_db(sd_device *device) {
 
                         if (device->devlink_priority != 0)
                                 fprintf(f, "L:%i\n", device->devlink_priority);
-
-                        if (device->watch_handle >= 0)
-                                fprintf(f, "W:%i\n", device->watch_handle);
                 }
 
                 if (device->usec_initialized > 0)
@@ -950,7 +1059,7 @@ int device_delete_db(sd_device *device) {
 
         assert(device);
 
-        r = device_get_id_filename(device, &id);
+        r = device_get_device_id(device, &id);
         if (r < 0)
                 return r;
 

src/libsystemd/sd-device/device-private.h

@@ -12,18 +12,22 @@
 
 int device_new_from_nulstr(sd_device **ret, uint8_t *nulstr, size_t len);
 int device_new_from_strv(sd_device **ret, char **strv);
+int device_new_from_watch_handle_at(sd_device **ret, int dirfd, int wd);
+static inline int device_new_from_watch_handle(sd_device **ret, int wd) {
+        return device_new_from_watch_handle_at(ret, -1, wd);
+}
 
-int device_get_id_filename(sd_device *device, const char **ret);
+int device_get_device_id(sd_device *device, const char **ret);
 
 int device_get_devlink_priority(sd_device *device, int *priority);
-int device_get_watch_handle(sd_device *device, int *handle);
+int device_get_watch_handle(sd_device *device);
 int device_get_devnode_mode(sd_device *device, mode_t *mode);
 int device_get_devnode_uid(sd_device *device, uid_t *uid);
 int device_get_devnode_gid(sd_device *device, gid_t *gid);
 
 void device_seal(sd_device *device);
 void device_set_is_initialized(sd_device *device);
-void device_set_watch_handle(sd_device *device, int fd);
+int device_set_watch_handle(sd_device *device, int wd);
 void device_set_db_persist(sd_device *device);
 void device_set_devlink_priority(sd_device *device, int priority);
 int device_ensure_usec_initialized(sd_device *device, sd_device *device_old);

src/libsystemd/sd-device/sd-device.c

@@ -62,7 +62,7 @@ static sd_device *device_free(sd_device *device) {
         free(device->subsystem);
         free(device->driver_subsystem);
         free(device->driver);
-        free(device->id_filename);
+        free(device->device_id);
         free(device->properties_strv);
         free(device->properties_nulstr);
 
@@ -623,7 +623,7 @@ _public_ int sd_device_new_from_device_id(sd_device **ret, const char *id) {
                 struct ifreq ifr = {};
                 int ifindex;
 
-                r = ifr.ifr_ifindex = parse_ifindex(&id[1]);
+                r = ifr.ifr_ifindex = parse_ifindex(id + 1);
                 if (r < 0)
                         return r;
 
@@ -652,15 +652,14 @@ _public_ int sd_device_new_from_device_id(sd_device **ret, const char *id) {
         }
 
         case '+': {
-                char subsys[PATH_MAX];
+                char subsys[NAME_MAX+1]; /* NAME_MAX does not include the trailing NUL. */
-                char *sysname;
+                const char *sysname;
 
-                (void) strscpy(subsys, sizeof(subsys), id + 1);
+                sysname = strchr(id + 1, ':');
-                sysname = strchr(subsys, ':');
                 if (!sysname)
                         return -EINVAL;
 
-                sysname[0] = '\0';
+                (void) strnscpy(subsys, sizeof(subsys), id + 1, sysname - id - 1);
                 sysname++;
 
                 return sd_device_new_from_subsystem_sysname(ret, subsys, sysname);
@@ -752,15 +751,34 @@ int device_set_subsystem(sd_device *device, const char *_subsystem) {
         return free_and_replace(device->subsystem, subsystem);
 }
 
-static int device_set_drivers_subsystem(sd_device *device, const char *_subsystem) {
+static int device_set_drivers_subsystem(sd_device *device) {
         _cleanup_free_ char *subsystem = NULL;
+        const char *syspath, *drivers, *p;
         int r;
 
         assert(device);
-        assert(_subsystem);
-        assert(*_subsystem);
 
-        subsystem = strdup(_subsystem);
+        r = sd_device_get_syspath(device, &syspath);
+        if (r < 0)
+                return r;
+
+        drivers = strstr(syspath, "/drivers/");
+        if (!drivers)
+                return -EINVAL;
+
+        for (p = drivers - 1; p >= syspath; p--)
+                if (*p == '/')
+                        break;
+
+        if (p <= syspath)
+                /* syspath does not start with /sys/ ?? */
+                return -EINVAL;
+        p++;
+        if (p >= drivers)
+                /* refuse duplicated slashes */
+                return -EINVAL;
+
+        subsystem = strndup(p, drivers - p);
         if (!subsystem)
                 return -ENOMEM;
 
@@ -772,60 +790,46 @@ static int device_set_drivers_subsystem(sd_device *device, const char *_subsyste
 }
 
 _public_ int sd_device_get_subsystem(sd_device *device, const char **ret) {
-        const char *syspath, *drivers = NULL;
         int r;
 
         assert_return(device, -EINVAL);
 
-        r = sd_device_get_syspath(device, &syspath);
-        if (r < 0)
-                return r;
-
         if (!device->subsystem_set) {
                 _cleanup_free_ char *subsystem = NULL;
+                const char *syspath;
                 char *path;
 
+                r = sd_device_get_syspath(device, &syspath);
+                if (r < 0)
+                        return r;
+
                 /* read 'subsystem' link */
                 path = strjoina(syspath, "/subsystem");
                 r = readlink_value(path, &subsystem);
-                if (r >= 0)
+                if (r < 0 && r != -ENOENT)
+                        return log_device_debug_errno(device, r,
+                                                      "sd-device: Failed to read subsystem for %s: %m",
+                                                      device->devpath);
+
+                if (subsystem)
                         r = device_set_subsystem(device, subsystem);
                 /* use implicit names */
                 else if (path_startswith(device->devpath, "/module/"))
                         r = device_set_subsystem(device, "module");
-                else if (!(drivers = strstr(syspath, "/drivers/")) &&
+                else if (strstr(syspath, "/drivers/"))
-                         PATH_STARTSWITH_SET(device->devpath, "/subsystem/",
+                        r = device_set_drivers_subsystem(device);
+                else if (PATH_STARTSWITH_SET(device->devpath, "/subsystem/",
                                                               "/class/",
                                                               "/bus/"))
                         r = device_set_subsystem(device, "subsystem");
-                if (r < 0 && r != -ENOENT)
+                else {
-                        return log_device_debug_errno(device, r, "sd-device: Failed to set subsystem for %s: %m", device->devpath);
+                        device->subsystem_set = true;
-
+                        r = 0;
-                device->subsystem_set = true;
-        } else if (!device->driver_subsystem_set)
-                drivers = strstr(syspath, "/drivers/");
-
-        if (!device->driver_subsystem_set) {
-                if (drivers) {
-                        _cleanup_free_ char *subpath = NULL;
-
-                        subpath = strndup(syspath, drivers - syspath);
-                        if (!subpath)
-                                r = -ENOMEM;
-                        else {
-                                const char *subsys;
-
-                                subsys = strrchr(subpath, '/');
-                                if (!subsys)
-                                        r = -EINVAL;
-                                else
-                                        r = device_set_drivers_subsystem(device, subsys + 1);
-                        }
-                        if (r < 0 && r != -ENOENT)
-                                return log_device_debug_errno(device, r, "sd-device: Failed to set subsystem for driver %s: %m", device->devpath);
                 }
-
+                if (r < 0)
-                device->driver_subsystem_set = true;
+                        return log_device_debug_errno(device, r,
+                                                      "sd-device: Failed to set subsystem for %s: %m",
+                                                      device->devpath);
         }
 
         if (!device->subsystem)
@@ -987,7 +991,7 @@ _public_ int sd_device_get_devname(sd_device *device, const char **devname) {
         return 0;
 }
 
-static int device_set_sysname(sd_device *device) {
+static int device_set_sysname_and_sysnum(sd_device *device) {
         _cleanup_free_ char *sysname = NULL;
         const char *sysnum = NULL;
         const char *pos;
@@ -1024,7 +1028,6 @@ static int device_set_sysname(sd_device *device) {
         if (len == 0)
                 sysnum = NULL;
 
-        device->sysname_set = true;
         device->sysnum = sysnum;
         return free_and_replace(device->sysname, sysname);
 }
@@ -1034,14 +1037,12 @@ _public_ int sd_device_get_sysname(sd_device *device, const char **ret) {
 
         assert_return(device, -EINVAL);
 
-        if (!device->sysname_set) {
+        if (!device->sysname) {
-                r = device_set_sysname(device);
+                r = device_set_sysname_and_sysnum(device);
                 if (r < 0)
                         return r;
         }
 
-        assert_return(device->sysname, -ENOENT);
-
         if (ret)
                 *ret = device->sysname;
         return 0;
@@ -1052,8 +1053,8 @@ _public_ int sd_device_get_sysnum(sd_device *device, const char **ret) {
 
         assert_return(device, -EINVAL);
 
-        if (!device->sysname_set) {
+        if (!device->sysname) {
-                r = device_set_sysname(device);
+                r = device_set_sysname_and_sysnum(device);
                 if (r < 0)
                         return r;
         }
@@ -1237,10 +1238,10 @@ static int handle_db_line(sd_device *device, char key, const char *value) {
 
                 break;
         case 'W':
-                r = safe_atoi(value, &device->watch_handle);
+                /* Deprecated. Previously, watch handle is both saved in database and /run/udev/watch.
-                if (r < 0)
+                 * However, the handle saved in database may not be updated when the handle is updated
-                        return r;
+                 * or removed. Moreover, it is not necessary to store the handle within the database,
-
+                 * as its value becomes meaningless when udevd is restarted. */
                 break;
         case 'V':
                 r = safe_atou(value, &device->database_version);
@@ -1255,11 +1256,11 @@ static int handle_db_line(sd_device *device, char key, const char *value) {
         return 0;
 }
 
-int device_get_id_filename(sd_device *device, const char **ret) {
+int device_get_device_id(sd_device *device, const char **ret) {
         assert(device);
         assert(ret);
 
-        if (!device->id_filename) {
+        if (!device->device_id) {
                 _cleanup_free_ char *id = NULL;
                 const char *subsystem;
                 dev_t devnum;
@@ -1296,7 +1297,6 @@ int device_get_id_filename(sd_device *device, const char **ret) {
                         if (!subsystem)
                                 return -EINVAL;
 
-
                         if (streq(subsystem, "drivers"))
                                 /* the 'drivers' pseudo-subsystem is special, and needs the real subsystem
                                  * encoded as well */
@@ -1307,10 +1307,13 @@ int device_get_id_filename(sd_device *device, const char **ret) {
                                 return -ENOMEM;
                 }
 
-                device->id_filename = TAKE_PTR(id);
+                if (!filename_is_valid(id))
+                        return -EINVAL;
+
+                device->device_id = TAKE_PTR(id);
         }
 
-        *ret = device->id_filename;
+        *ret = device->device_id;
         return 0;
 }
 
@@ -1407,7 +1410,7 @@ int device_read_db_internal(sd_device *device, bool force) {
         if (device->db_loaded || (!force && device->sealed))
                 return 0;
 
-        r = device_get_id_filename(device, &id);
+        r = device_get_device_id(device, &id);
         if (r < 0)
                 return r;
 

src/network/networkd-can.c

@@ -52,7 +52,7 @@ int config_parse_can_bitrate(
         return 0;
 }
 
-static int link_up_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) {
+static int link_set_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) {
         int r;
 
         assert(link);
@@ -60,53 +60,24 @@ static int link_up_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link)
         if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER))
                 return 1;
 
-        r = sd_netlink_message_get_errno(m);
-        if (r < 0)
-                /* we warn but don't fail the link, as it may be brought up later */
-                log_link_message_warning_errno(link, m, r, "Could not bring up interface");
-
-        return 1;
-}
-
-static int link_up_can(Link *link) {
-        _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *req = NULL;
-        int r;
-
-        assert(link);
-
-        log_link_debug(link, "Bringing CAN link up");
-
-        r = sd_rtnl_message_new_link(link->manager->rtnl, &req, RTM_SETLINK, link->ifindex);
-        if (r < 0)
-                return log_link_error_errno(link, r, "Could not allocate RTM_SETLINK message: %m");
-
-        r = sd_rtnl_message_link_set_flags(req, IFF_UP, IFF_UP);
-        if (r < 0)
-                return log_link_error_errno(link, r, "Could not set link flags: %m");
-
-        r = netlink_call_async(link->manager->rtnl, NULL, req, link_up_handler,
-                               link_netlink_destroy_callback, link);
-        if (r < 0)
-                return log_link_error_errno(link, r, "Could not send rtnetlink message: %m");
-
-        link_ref(link);
-
-        return 0;
-}
-
-static int link_set_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) {
-        int r;
-
-        assert(link);
-
-        log_link_debug(link, "Set link");
-
         r = sd_netlink_message_get_errno(m);
         if (r < 0 && r != -EEXIST) {
                 log_link_message_warning_errno(link, m, r, "Failed to configure CAN link");
                 link_enter_failed(link);
+                return 1;
         }
 
+        log_link_debug(link, "Link set");
+
+        r = link_activate(link);
+        if (r < 0) {
+                link_enter_failed(link);
+                return 1;
+        }
+
+        link->can_configured = true;
+        link_check_ready(link);
+
         return 1;
 }
 
@@ -255,9 +226,6 @@ static int link_set_can(Link *link) {
 
         link_ref(link);
 
-        if (!(link->flags & IFF_UP))
-                return link_up_can(link);
-
         return 0;
 }
 
@@ -290,30 +258,21 @@ int link_configure_can(Link *link) {
 
         if (streq_ptr(link->kind, "can")) {
                 /* The CAN interface must be down to configure bitrate, etc... */
-                if ((link->flags & IFF_UP)) {
+                if ((link->flags & IFF_UP))
                         r = link_down(link, link_down_handler);
-                        if (r < 0) {
+                else
-                                link_enter_failed(link);
-                                return r;
-                        }
-                } else {
                         r = link_set_can(link);
-                        if (r < 0) {
+                if (r < 0)
-                                link_enter_failed(link);
-                                return r;
-                        }
-                }
-
-                return 0;
-        }
-
-        if (!(link->flags & IFF_UP)) {
-                r = link_up_can(link);
-                if (r < 0) {
                         link_enter_failed(link);
-                        return r;
+                return r;
-                }
         }
 
+        r = link_activate(link);
+        if (r < 0)
+                return r;
+
+        link->can_configured = true;
+        link_check_ready(link);
+
         return 0;
 }

src/network/networkd-link.c

@@ -764,6 +764,15 @@ void link_check_ready(Link *link) {
         if (!link->network)
                 return;
 
+        if (link->iftype == ARPHRD_CAN) {
+                /* let's shortcut things for CAN which doesn't need most of checks below. */
+                if (!link->can_configured)
+                        return (void) log_link_debug(link, "%s(): CAN device is not configured.", __func__);
+
+                link_enter_configured(link);
+                return;
+        }
+
         if (!link->addresses_configured)
                 return (void) log_link_debug(link, "%s(): static addresses are not configured.", __func__);
 
@@ -1376,7 +1385,7 @@ static int link_up_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link)
         return 1;
 }
 
-static int link_up(Link *link) {
+int link_up(Link *link) {
         _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *req = NULL;
         int r;
 
@@ -1771,7 +1780,7 @@ static void link_drop(Link *link) {
         link_detach_from_manager(link);
 }
 
-static int link_joined(Link *link) {
+int link_activate(Link *link) {
         int r;
 
         assert(link);
@@ -1789,10 +1798,8 @@ static int link_joined(Link *link) {
                 _fallthrough_;
         case ACTIVATION_POLICY_ALWAYS_UP:
                 r = link_up(link);
-                if (r < 0) {
+                if (r < 0)
-                        link_enter_failed(link);
                         return r;
-                }
                 break;
         case ACTIVATION_POLICY_DOWN:
                 if (link->activated)
@@ -1800,16 +1807,27 @@ static int link_joined(Link *link) {
                 _fallthrough_;
         case ACTIVATION_POLICY_ALWAYS_DOWN:
                 r = link_down(link, NULL);
-                if (r < 0) {
+                if (r < 0)
-                        link_enter_failed(link);
                         return r;
-                }
                 break;
         default:
                 break;
         }
         link->activated = true;
 
+        return 0;
+}
+
+static int link_joined(Link *link) {
+        int r;
+
+        assert(link);
+        assert(link->network);
+
+        r = link_activate(link);
+        if (r < 0)
+                return r;
+
         if (link->network->bridge) {
                 r = link_set_bridge(link);
                 if (r < 0)
@@ -2076,6 +2094,7 @@ int link_configure(Link *link) {
                 return r;
 
         if (link->iftype == ARPHRD_CAN)
+                /* let's shortcut things for CAN which doesn't need most of what's done below. */
                 return link_configure_can(link);
 
         r = link_set_sysctl(link);
@@ -2567,6 +2586,10 @@ static int link_carrier_gained(Link *link) {
 
         assert(link);
 
+        if (link->iftype == ARPHRD_CAN)
+                /* let's shortcut things for CAN which doesn't need most of what's done below. */
+                return link_handle_bound_by_list(link);
+
         r = wifi_get_info(link);
         if (r < 0)
                 return r;
@@ -2625,6 +2648,10 @@ static int link_carrier_lost(Link *link) {
         if (link->network && link->network->ignore_carrier_loss)
                 return 0;
 
+        if (link->iftype == ARPHRD_CAN)
+                /* let's shortcut things for CAN which doesn't need most of what's done below. */
+                return link_handle_bound_by_list(link);
+
         /* Some devices reset itself while setting the MTU. This causes the DHCP client fall into a loop.
          * setting_mtu keep track whether the device got reset because of setting MTU and does not drop the
          * configuration and stop the clients as well. */
@@ -2712,6 +2739,10 @@ static int link_admin_state_down(Link *link) {
                 return 0;
 
         if (link->network->activation_policy == ACTIVATION_POLICY_ALWAYS_UP) {
+                if (streq_ptr(link->kind, "can") && !link->can_configured)
+                        /* CAN device needs to be down on configure. */
+                        return 0;
+
                 log_link_info(link, "ActivationPolicy is \"always-on\", forcing link up");
                 return link_up(link);
         }

src/network/networkd-link.h

@@ -131,6 +131,7 @@ typedef struct Link {
         bool setting_genmode:1;
         bool ipv6_mtu_set:1;
         bool bridge_mdb_configured:1;
+        bool can_configured:1;
         bool activated:1;
 
         sd_dhcp_server *dhcp_server;
@@ -207,7 +208,9 @@ DEFINE_TRIVIAL_DESTRUCTOR(link_netlink_destroy_callback, Link, link_unref);
 
 int link_get(Manager *m, int ifindex, Link **ret);
 
+int link_up(Link *link);
 int link_down(Link *link, link_netlink_message_handler_t callback);
+int link_activate(Link *link);
 
 void link_enter_failed(Link *link);
 

src/test/test-udev.c

@@ -130,7 +130,7 @@ static int run(int argc, char *argv[]) {
                 }
         }
 
-        udev_event_execute_rules(event, 3 * USEC_PER_SEC, SIGKILL, NULL, rules);
+        udev_event_execute_rules(event, -1, 3 * USEC_PER_SEC, SIGKILL, NULL, rules);
         udev_event_execute_run(event, 3 * USEC_PER_SEC, SIGKILL);
 
         return 0;

src/udev/udev-event.c

@@ -911,8 +911,9 @@ static int update_devnode(UdevEvent *event) {
         return udev_node_add(dev, apply_mac, event->mode, event->uid, event->gid, event->seclabel_list);
 }
 
-static void event_execute_rules_on_remove(
+static int event_execute_rules_on_remove(
                 UdevEvent *event,
+                int inotify_fd,
                 usec_t timeout_usec,
                 int timeout_signal,
                 Hashmap *properties_list,
@@ -933,13 +934,14 @@ static void event_execute_rules_on_remove(
         if (r < 0)
                 log_device_debug_errno(dev, r, "Failed to delete database under /run/udev/data/, ignoring: %m");
 
-        if (sd_device_get_devnum(dev, NULL) >= 0)
+        (void) udev_watch_end(inotify_fd, dev);
-                (void) udev_watch_end(dev);
 
-        (void) udev_rules_apply_to_event(rules, event, timeout_usec, timeout_signal, properties_list);
+        r = udev_rules_apply_to_event(rules, event, timeout_usec, timeout_signal, properties_list);
 
         if (sd_device_get_devnum(dev, NULL) >= 0)
                 (void) udev_node_remove(dev);
+
+        return r;
 }
 
 static int udev_event_on_move(sd_device *dev) {
@@ -971,12 +973,14 @@ static int copy_all_tags(sd_device *d, sd_device *s) {
         return 0;
 }
 
-int udev_event_execute_rules(UdevEvent *event,
+int udev_event_execute_rules(
-                             usec_t timeout_usec,
+                UdevEvent *event,
-                             int timeout_signal,
+                int inotify_fd, /* This may be negative */
-                             Hashmap *properties_list,
+                usec_t timeout_usec,
-                             UdevRules *rules) {
+                int timeout_signal,
-        const char *subsystem;
+                Hashmap *properties_list,
+                UdevRules *rules) {
+
         sd_device_action_t action;
         sd_device *dev;
         int r;
@@ -986,18 +990,15 @@ int udev_event_execute_rules(UdevEvent *event,
 
         dev = event->dev;
 
-        r = sd_device_get_subsystem(dev, &subsystem);
-        if (r < 0)
-                return log_device_error_errno(dev, r, "Failed to get subsystem: %m");
-
         r = sd_device_get_action(dev, &action);
         if (r < 0)
                 return log_device_error_errno(dev, r, "Failed to get ACTION: %m");
 
-        if (action == SD_DEVICE_REMOVE) {
+        if (action == SD_DEVICE_REMOVE)
-                event_execute_rules_on_remove(event, timeout_usec, timeout_signal, properties_list, rules);
+                return event_execute_rules_on_remove(event, inotify_fd, timeout_usec, timeout_signal, properties_list, rules);
-                return 0;
+
-        }
+        /* Disable watch during event processing. */
+        (void) udev_watch_end(inotify_fd, event->dev);
 
         r = device_clone_with_db(dev, &event->dev_db_clone);
         if (r < 0)
@@ -1007,10 +1008,6 @@ int udev_event_execute_rules(UdevEvent *event,
         if (r < 0)
                 log_device_warning_errno(dev, r, "Failed to copy all tags from old database entry, ignoring: %m");
 
-        if (sd_device_get_devnum(dev, NULL) >= 0)
-                /* Disable watch during event processing. */
-                (void) udev_watch_end(event->dev_db_clone);
-
         if (action == SD_DEVICE_MOVE) {
                 r = udev_event_on_move(event->dev);
                 if (r < 0)
@@ -1048,11 +1045,7 @@ int udev_event_execute_rules(UdevEvent *event,
         /* Yes, we run update_devnode() twice, because in the first invocation, that is before update of udev database,
          * it could happen that two contenders are replacing each other's symlink. Hence we run it again to make sure
          * symlinks point to devices that claim them with the highest priority. */
-        r = update_devnode(event);
+        return update_devnode(event);
-        if (r < 0)
-                return r;
-
-        return 0;
 }
 
 void udev_event_execute_run(UdevEvent *event, usec_t timeout_usec, int timeout_signal) {
@@ -1087,3 +1080,24 @@ void udev_event_execute_run(UdevEvent *event, usec_t timeout_usec, int timeout_s
                 }
         }
 }
+
+int udev_event_process_inotify_watch(UdevEvent *event, int inotify_fd) {
+        sd_device *dev;
+
+        assert(event);
+        assert(inotify_fd >= 0);
+
+        dev = event->dev;
+
+        assert(dev);
+
+        if (device_for_action(dev, SD_DEVICE_REMOVE))
+                return 0;
+
+        if (event->inotify_watch)
+                (void) udev_watch_begin(inotify_fd, dev);
+        else
+                (void) udev_watch_end(inotify_fd, dev);
+
+        return 0;
+}

src/udev/udev-event.h

@@ -51,21 +51,30 @@ UdevEvent *udev_event_new(sd_device *dev, usec_t exec_delay_usec, sd_netlink *rt
 UdevEvent *udev_event_free(UdevEvent *event);
 DEFINE_TRIVIAL_CLEANUP_FUNC(UdevEvent*, udev_event_free);
 
-size_t udev_event_apply_format(UdevEvent *event,
+size_t udev_event_apply_format(
-                               const char *src, char *dest, size_t size,
+                UdevEvent *event,
-                               bool replace_whitespace);
+                const char *src,
+                char *dest,
+                size_t size,
+                bool replace_whitespace);
 int udev_check_format(const char *value, size_t *offset, const char **hint);
-int udev_event_spawn(UdevEvent *event,
+int udev_event_spawn(
-                     usec_t timeout_usec,
+                UdevEvent *event,
-                     int timeout_signal,
+                usec_t timeout_usec,
-                     bool accept_failure,
+                int timeout_signal,
-                     const char *cmd, char *result, size_t ressize);
+                bool accept_failure,
-int udev_event_execute_rules(UdevEvent *event,
+                const char *cmd,
-                             usec_t timeout_usec,
+                char *result,
-                             int timeout_signal,
+                size_t ressize);
-                             Hashmap *properties_list,
+int udev_event_execute_rules(
-                             UdevRules *rules);
+                UdevEvent *event,
+                int inotify_fd,
+                usec_t timeout_usec,
+                int timeout_signal,
+                Hashmap *properties_list,
+                UdevRules *rules);
 void udev_event_execute_run(UdevEvent *event, usec_t timeout_usec, int timeout_signal);
+int udev_event_process_inotify_watch(UdevEvent *event, int inotify_fd);
 
 static inline usec_t udev_warn_timeout(usec_t timeout_usec) {
         return DIV_ROUND_UP(timeout_usec, 3);

src/udev/udev-node.c

@@ -30,7 +30,7 @@
 
 static int node_symlink(sd_device *dev, const char *node, const char *slink) {
         _cleanup_free_ char *slink_dirname = NULL, *target = NULL;
-        const char *id_filename, *slink_tmp;
+        const char *id, *slink_tmp;
         struct stat stats;
         int r;
 
@@ -81,10 +81,10 @@ static int node_symlink(sd_device *dev, const char *node, const char *slink) {
         }
 
         log_device_debug(dev, "Atomically replace '%s'", slink);
-        r = device_get_id_filename(dev, &id_filename);
+        r = device_get_device_id(dev, &id);
         if (r < 0)
-                return log_device_error_errno(dev, r, "Failed to get id_filename: %m");
+                return log_device_error_errno(dev, r, "Failed to get device id: %m");
-        slink_tmp = strjoina(slink, ".tmp-", id_filename);
+        slink_tmp = strjoina(slink, ".tmp-", id);
         (void) unlink(slink_tmp);
         do {
                 r = mkdir_parents_label(slink_tmp, 0755);
@@ -147,7 +147,7 @@ static int link_find_prioritized(sd_device *dev, bool add, const char *stackdir,
 
         FOREACH_DIRENT_ALL(dent, dir, break) {
                 _cleanup_(sd_device_unrefp) sd_device *dev_db = NULL;
-                const char *devnode, *id_filename;
+                const char *devnode, *id;
                 int db_prio = 0;
 
                 if (dent->d_name[0] == '\0')
@@ -157,11 +157,11 @@ static int link_find_prioritized(sd_device *dev, bool add, const char *stackdir,
 
                 log_device_debug(dev, "Found '%s' claiming '%s'", dent->d_name, stackdir);
 
-                if (device_get_id_filename(dev, &id_filename) < 0)
+                if (device_get_device_id(dev, &id) < 0)
                         continue;
 
                 /* did we find ourself? */
-                if (streq(dent->d_name, id_filename))
+                if (streq(dent->d_name, id))
                         continue;
 
                 if (sd_device_new_from_device_id(&dev_db, dent->d_name) < 0)
@@ -229,21 +229,21 @@ static size_t escape_path(const char *src, char *dest, size_t size) {
 static int link_update(sd_device *dev, const char *slink, bool add) {
         _cleanup_free_ char *filename = NULL, *dirname = NULL;
         char name_enc[PATH_MAX];
-        const char *id_filename;
+        const char *id;
         int i, r, retries;
 
         assert(dev);
         assert(slink);
 
-        r = device_get_id_filename(dev, &id_filename);
+        r = device_get_device_id(dev, &id);
         if (r < 0)
-                return log_device_debug_errno(dev, r, "Failed to get id_filename: %m");
+                return log_device_debug_errno(dev, r, "Failed to get device id: %m");
 
         escape_path(slink + STRLEN("/dev"), name_enc, sizeof(name_enc));
         dirname = path_join("/run/udev/links/", name_enc);
         if (!dirname)
                 return log_oom();
-        filename = path_join(dirname, id_filename);
+        filename = path_join(dirname, id);
         if (!filename)
                 return log_oom();
 
@@ -348,7 +348,7 @@ int udev_node_update_old_links(sd_device *dev, sd_device *dev_old) {
 static int node_permissions_apply(sd_device *dev, bool apply_mac,
                                   mode_t mode, uid_t uid, gid_t gid,
                                   OrderedHashmap *seclabel_list) {
-        const char *devnode, *subsystem, *id_filename = NULL;
+        const char *devnode, *subsystem, *id = NULL;
         bool apply_mode, apply_uid, apply_gid;
         _cleanup_close_ int node_fd = -1;
         struct stat stats;
@@ -366,7 +366,7 @@ static int node_permissions_apply(sd_device *dev, bool apply_mac,
         r = sd_device_get_devnum(dev, &devnum);
         if (r < 0)
                 return log_device_debug_errno(dev, r, "Failed to get devnum: %m");
-        (void) device_get_id_filename(dev, &id_filename);
+        (void) device_get_device_id(dev, &id);
 
         if (streq(subsystem, "block"))
                 mode |= S_IFBLK;
@@ -388,7 +388,7 @@ static int node_permissions_apply(sd_device *dev, bool apply_mac,
 
         if ((mode != MODE_INVALID && (stats.st_mode & S_IFMT) != (mode & S_IFMT)) || stats.st_rdev != devnum) {
                 log_device_debug(dev, "Found node '%s' with non-matching devnum %s, skipping handling.",
-                                 devnode, id_filename);
+                                 devnode, strna(id));
                 return 0; /* We might process a device that already got replaced by the time we have a look
                            * at it, handle this gracefully and step away. */
         }
@@ -509,10 +509,10 @@ int udev_node_add(sd_device *dev, bool apply,
                 return log_device_debug_errno(dev, r, "Failed to get devnode: %m");
 
         if (DEBUG_LOGGING) {
-                const char *id_filename = NULL;
+                const char *id = NULL;
 
-                (void) device_get_id_filename(dev, &id_filename);
+                (void) device_get_device_id(dev, &id);
-                log_device_debug(dev, "Handling device node '%s', devnum=%s", devnode, strnull(id_filename));
+                log_device_debug(dev, "Handling device node '%s', devnum=%s", devnode, strna(id));
         }
 
         r = node_permissions_apply(dev, apply, mode, uid, gid, seclabel_list);

src/udev/udev-watch.c

@@ -5,72 +5,60 @@
  */
 
 #include <sys/inotify.h>
-#include <unistd.h>
 
 #include "alloc-util.h"
 #include "device-private.h"
 #include "device-util.h"
 #include "dirent-util.h"
 #include "fs-util.h"
-#include "mkdir.h"
+#include "parse-util.h"
-#include "stdio-util.h"
 #include "udev-watch.h"
 
-static int inotify_fd = -1;
+int udev_watch_restore(int inotify_fd) {
-
-/* inotify descriptor, will be shared with rules directory;
- * set to cloexec since we need our children to be able to add
- * watches for us. */
-int udev_watch_init(void) {
-        inotify_fd = inotify_init1(IN_CLOEXEC);
-        if (inotify_fd < 0)
-                return -errno;
-
-        return inotify_fd;
-}
-
-/* Move any old watches directory out of the way, and then restore the watches. */
-int udev_watch_restore(void) {
         struct dirent *ent;
         DIR *dir;
         int r;
 
-        if (inotify_fd < 0)
+        /* Move any old watches directory out of the way, and then restore the watches. */
-                return log_debug_errno(SYNTHETIC_ERRNO(EINVAL),
+
-                                       "Invalid inotify descriptor.");
+        assert(inotify_fd >= 0);
 
         if (rename("/run/udev/watch", "/run/udev/watch.old") < 0) {
                 if (errno != ENOENT)
-                        return log_warning_errno(errno, "Failed to move watches directory /run/udev/watch. Old watches will not be restored: %m");
+                        return log_warning_errno(errno, "Failed to move watches directory /run/udev/watch. "
+                                                 "Old watches will not be restored: %m");
 
                 return 0;
         }
 
         dir = opendir("/run/udev/watch.old");
         if (!dir)
-                return log_warning_errno(errno, "Failed to open old watches directory /run/udev/watch.old. Old watches will not be restored: %m");
+                return log_warning_errno(errno, "Failed to open old watches directory /run/udev/watch.old. "
+                                         "Old watches will not be restored: %m");
 
         FOREACH_DIRENT_ALL(ent, dir, break) {
                 _cleanup_(sd_device_unrefp) sd_device *dev = NULL;
-                _cleanup_free_ char *device = NULL;
+                int wd;
 
                 if (ent->d_name[0] == '.')
                         continue;
 
-                r = readlinkat_malloc(dirfd(dir), ent->d_name, &device);
+                /* For backward compatibility, read symlink from watch handle to device id, and ignore
-                if (r < 0) {
+                 * the opposite direction symlink. */
-                        log_debug_errno(r, "Failed to read link '/run/udev/watch.old/%s', ignoring: %m", ent->d_name);
-                        goto unlink;
-                }
 
-                r = sd_device_new_from_device_id(&dev, device);
+                if (safe_atoi(ent->d_name, &wd) < 0)
+                        goto unlink;
+
+                r = device_new_from_watch_handle_at(&dev, dirfd(dir), wd);
                 if (r < 0) {
-                        log_debug_errno(r, "Failed to create sd_device object for '%s', ignoring: %m", device);
+                        log_full_errno(r == -ENODEV ? LOG_DEBUG : LOG_WARNING, r,
+                                       "Failed to create sd_device object from saved watch handle '%s', ignoring: %m",
+                                       ent->d_name);
                         goto unlink;
                 }
 
                 log_device_debug(dev, "Restoring old watch");
-                (void) udev_watch_begin(dev);
+                (void) udev_watch_begin(inotify_fd, dev);
 unlink:
                 (void) unlinkat(dirfd(dir), ent->d_name, 0);
         }
@@ -81,94 +69,54 @@ unlink:
         return 0;
 }
 
-int udev_watch_begin(sd_device *dev) {
+int udev_watch_begin(int inotify_fd, sd_device *dev) {
-        char filename[STRLEN("/run/udev/watch/") + DECIMAL_STR_MAX(int)];
+        const char *devnode;
-        const char *devnode, *id_filename;
         int wd, r;
 
-        if (inotify_fd < 0)
+        assert(inotify_fd >= 0);
-                return log_debug_errno(SYNTHETIC_ERRNO(EINVAL),
+        assert(dev);
-                                       "Invalid inotify descriptor.");
 
         r = sd_device_get_devname(dev, &devnode);
         if (r < 0)
-                return log_device_error_errno(dev, r, "Failed to get device name: %m");
+                return log_device_debug_errno(dev, r, "Failed to get device name: %m");
 
         log_device_debug(dev, "Adding watch on '%s'", devnode);
         wd = inotify_add_watch(inotify_fd, devnode, IN_CLOSE_WRITE);
-        if (wd < 0)
+        if (wd < 0) {
-                return log_device_full_errno(dev, errno == ENOENT ? LOG_DEBUG : LOG_ERR, errno,
+                r = log_device_full_errno(dev, errno == ENOENT ? LOG_DEBUG : LOG_WARNING,
-                                             "Failed to add device '%s' to watch: %m", devnode);
+                                          errno, "Failed to add device '%s' to watch: %m", devnode);
 
-        device_set_watch_handle(dev, wd);
+                (void) device_set_watch_handle(dev, -1);
+                return r;
+        }
 
-        xsprintf(filename, "/run/udev/watch/%d", wd);
+        r = device_set_watch_handle(dev, wd);
-        r = mkdir_parents(filename, 0755);
         if (r < 0)
-                return log_device_error_errno(dev, r, "Failed to create parent directory of '%s': %m", filename);
+                return log_device_warning_errno(dev, r, "Failed to save watch handle in /run/udev/watch: %m");
-        (void) unlink(filename);
-
-        r = device_get_id_filename(dev, &id_filename);
-        if (r < 0)
-                return log_device_error_errno(dev, r, "Failed to get device id-filename: %m");
-
-        if (symlink(id_filename, filename) < 0)
-                return log_device_error_errno(dev, errno, "Failed to create symlink %s: %m", filename);
 
         return 0;
 }
 
-int udev_watch_end(sd_device *dev) {
+int udev_watch_end(int inotify_fd, sd_device *dev) {
-        char filename[STRLEN("/run/udev/watch/") + DECIMAL_STR_MAX(int)];
+        int wd;
-        int wd, r;
 
+        assert(dev);
+
+        /* This may be called by 'udevadm test'. In that case, inotify_fd is not initialized. */
         if (inotify_fd < 0)
-                return 0; /* Nothing to do. */
-
-        r = device_get_watch_handle(dev, &wd);
-        if (r == -ENOENT)
                 return 0;
-        if (r < 0)
-                return log_device_debug_errno(dev, r, "Failed to get watch handle, ignoring: %m");
 
-        log_device_debug(dev, "Removing watch");
+        if (sd_device_get_devname(dev, NULL) < 0)
-        (void) inotify_rm_watch(inotify_fd, wd);
+                return 0;
 
-        xsprintf(filename, "/run/udev/watch/%d", wd);
+        wd = device_get_watch_handle(dev);
-        (void) unlink(filename);
+        if (wd < 0)
-
+                log_device_debug_errno(dev, wd, "Failed to get watch handle, ignoring: %m");
-        device_set_watch_handle(dev, -1);
+        else {
+                log_device_debug(dev, "Removing watch");
+                (void) inotify_rm_watch(inotify_fd, wd);
+        }
+        (void) device_set_watch_handle(dev, -1);
 
         return 0;
 }
-
-int udev_watch_lookup(int wd, sd_device **ret) {
-        char filename[STRLEN("/run/udev/watch/") + DECIMAL_STR_MAX(int)];
-        _cleanup_free_ char *device = NULL;
-        int r;
-
-        assert(ret);
-
-        if (inotify_fd < 0)
-                return log_debug_errno(SYNTHETIC_ERRNO(EINVAL),
-                                       "Invalid inotify descriptor.");
-
-        if (wd < 0)
-                return log_debug_errno(SYNTHETIC_ERRNO(EINVAL),
-                                       "Invalid watch handle.");
-
-        xsprintf(filename, "/run/udev/watch/%d", wd);
-        r = readlink_malloc(filename, &device);
-        if (r == -ENOENT)
-                return 0;
-        if (r < 0)
-                return log_debug_errno(r, "Failed to read link '%s': %m", filename);
-
-        r = sd_device_new_from_device_id(ret, device);
-        if (r == -ENODEV)
-                return 0;
-        if (r < 0)
-                return log_debug_errno(r, "Failed to create sd_device object for '%s': %m", device);
-
-        return 1;
-}

src/udev/udev-watch.h

@@ -3,8 +3,6 @@
 
 #include "sd-device.h"
 
-int udev_watch_init(void);
+int udev_watch_restore(int inotify_fd);
-int udev_watch_restore(void);
+int udev_watch_begin(int inotify_fd, sd_device *dev);
-int udev_watch_begin(sd_device *dev);
+int udev_watch_end(int inotify_fd, sd_device *dev);
-int udev_watch_end(sd_device *dev);
-int udev_watch_lookup(int wd, sd_device **ret);

src/udev/udevadm-test.c

@@ -141,7 +141,7 @@ int test_main(int argc, char *argv[], void *userdata) {
         assert_se(sigfillset(&mask) >= 0);
         assert_se(sigprocmask(SIG_SETMASK, &mask, &sigmask_orig) >= 0);
 
-        udev_event_execute_rules(event, 60 * USEC_PER_SEC, SIGKILL, NULL, rules);
+        udev_event_execute_rules(event, -1, 60 * USEC_PER_SEC, SIGKILL, NULL, rules);
 
         FOREACH_DEVICE_PROPERTY(dev, key, value)
                 printf("%s=%s\n", key, value);

src/udev/udevd.c

@@ -92,10 +92,12 @@ typedef struct Manager {
 
         sd_device_monitor *monitor;
         struct udev_ctrl *ctrl;
-        int fd_inotify;
         int worker_watch[2];
 
+        /* used by udev-watch */
+        int inotify_fd;
         sd_event_source *inotify_event;
+
         sd_event_source *kill_workers_event;
 
         usec_t last_usec;
@@ -304,7 +306,7 @@ static Manager* manager_free(Manager *manager) {
         hashmap_free_free_free(manager->properties);
         udev_rules_free(manager->rules);
 
-        safe_close(manager->fd_inotify);
+        safe_close(manager->inotify_fd);
         safe_close_pair(manager->worker_watch);
 
         return mfree(manager);
@@ -473,7 +475,7 @@ static int worker_process_device(Manager *manager, sd_device *dev) {
                  * degree — they go hand-in-hand after all. */
 
                 log_device_debug(dev, "Block device is currently locked, installing watch to wait until the lock is released.");
-                (void) udev_watch_begin(dev);
+                (void) udev_watch_begin(manager->inotify_fd, dev);
 
                 /* Now the watch is installed, let's lock the device again, maybe in the meantime things changed */
                 r = worker_lock_block_device(dev, &fd_lock);
@@ -484,7 +486,13 @@ static int worker_process_device(Manager *manager, sd_device *dev) {
         (void) worker_mark_block_device_read_only(dev);
 
         /* apply rules, create node, symlinks */
-        r = udev_event_execute_rules(udev_event, arg_event_timeout_usec, arg_timeout_signal, manager->properties, manager->rules);
+        r = udev_event_execute_rules(
+                          udev_event,
+                          manager->inotify_fd,
+                          arg_event_timeout_usec,
+                          arg_timeout_signal,
+                          manager->properties,
+                          manager->rules);
         if (r < 0)
                 return r;
 
@@ -494,14 +502,9 @@ static int worker_process_device(Manager *manager, sd_device *dev) {
                 /* in case rtnl was initialized */
                 manager->rtnl = sd_netlink_ref(udev_event->rtnl);
 
-        /* apply/restore/end inotify watch */
+        r = udev_event_process_inotify_watch(udev_event, manager->inotify_fd);
-        if (udev_event->inotify_watch) {
+        if (r < 0)
-                (void) udev_watch_begin(dev);
+                return r;
-                r = device_update_db(dev);
-                if (r < 0)
-                        return log_device_debug_errno(dev, r, "Failed to update database under /run/udev/data/: %m");
-        } else
-                (void) udev_watch_end(dev);
 
         log_device_uevent(dev, "Device processed");
         return 0;
@@ -872,7 +875,7 @@ static void manager_exit(Manager *manager) {
         manager->ctrl = udev_ctrl_unref(manager->ctrl);
 
         manager->inotify_event = sd_event_source_unref(manager->inotify_event);
-        manager->fd_inotify = safe_close(manager->fd_inotify);
+        manager->inotify_fd = safe_close(manager->inotify_fd);
 
         manager->monitor = sd_device_monitor_unref(manager->monitor);
 
@@ -1299,17 +1302,21 @@ static int on_inotify(sd_event_source *s, int fd, uint32_t revents, void *userda
                 _cleanup_(sd_device_unrefp) sd_device *dev = NULL;
                 const char *devnode;
 
-                if (udev_watch_lookup(e->wd, &dev) <= 0)
+                r = device_new_from_watch_handle(&dev, e->wd);
+                if (r < 0) {
+                        log_debug_errno(r, "Failed to create sd_device object from watch handle, ignoring: %m");
                         continue;
+                }
 
                 if (sd_device_get_devname(dev, &devnode) < 0)
                         continue;
 
                 log_device_debug(dev, "Inotify event: %x for %s", e->mask, devnode);
                 if (e->mask & IN_CLOSE_WRITE)
-                        synthesize_change(dev);
+                        (void) synthesize_change(dev);
-                else if (e->mask & IN_IGNORED)
+
-                        udev_watch_end(dev);
+                /* Do not handle IN_IGNORED here. It should be handled by worker in 'remove' uevent;
+                 * udev_event_execute_rules() -> event_execute_rules_on_remove() -> udev_watch_end(). */
         }
 
         return 1;
@@ -1669,7 +1676,7 @@ static int manager_new(Manager **ret, int fd_ctrl, int fd_uevent, const char *cg
                 return log_oom();
 
         *manager = (Manager) {
-                .fd_inotify = -1,
+                .inotify_fd = -1,
                 .worker_watch = { -1, -1 },
                 .cgroup = cgroup,
         };
@@ -1722,12 +1729,11 @@ static int main_loop(Manager *manager) {
         if (r < 0)
                 return log_error_errno(r, "Failed to enable SO_PASSCRED: %m");
 
-        r = udev_watch_init();
+        manager->inotify_fd = inotify_init1(IN_CLOEXEC);
-        if (r < 0)
+        if (manager->inotify_fd < 0)
-                return log_error_errno(r, "Failed to create inotify descriptor: %m");
+                return log_error_errno(errno, "Failed to create inotify descriptor: %m");
-        manager->fd_inotify = r;
 
-        udev_watch_restore();
+        udev_watch_restore(manager->inotify_fd);
 
         /* block and listen to all signals on signalfd */
         assert_se(sigprocmask_many(SIG_BLOCK, NULL, SIGTERM, SIGINT, SIGHUP, SIGCHLD, -1) >= 0);
@@ -1772,7 +1778,7 @@ static int main_loop(Manager *manager) {
         if (r < 0)
                 return log_error_errno(r, "Failed to set IDLE event priority for udev control event source: %m");
 
-        r = sd_event_add_io(manager->event, &manager->inotify_event, manager->fd_inotify, EPOLLIN, on_inotify, manager);
+        r = sd_event_add_io(manager->event, &manager->inotify_event, manager->inotify_fd, EPOLLIN, on_inotify, manager);
         if (r < 0)
                 return log_error_errno(r, "Failed to create inotify event source: %m");
 

test/TEST-17-UDEV/test.sh

@@ -8,7 +8,7 @@ TEST_NO_NSPAWN=1
 # shellcheck source=test/test-functions
 . "${TEST_BASE_DIR:?}/test-functions"
 
-QEMU_TIMEOUT=500
+QEMU_TIMEOUT=800
 
 test_append_files() {
     (

test/test-functions

@@ -227,10 +227,10 @@ if [[ "$IS_BUILT_WITH_ASAN" = "yes" ]]; then
     QEMU_SMP="${QEMU_SMP:-4}"
 
     # We need to correctly distinguish between gcc's and clang's ASan DSOs.
-    if ASAN_RT_NAME="$(ldd "$SYSTEMD" | awk '/libasan.so/ {x=$1; exit} END {print x; exit x==""}')"; then
+    if ASAN_RT_NAME="$(awk '/libasan.so/ {x=$1; exit} END {print x; exit x==""}' < <(ldd "$SYSTEMD"))"; then
         ASAN_COMPILER=gcc
         ASAN_RT_PATH="$(readlink -f "$(${CC:-gcc} --print-file-name "$ASAN_RT_NAME")")"
-    elif ASAN_RT_NAME="$(ldd "$SYSTEMD" | awk '/libclang_rt.asan/ {x=$1; exit} END {print x; exit x==""}')"; then
+    elif ASAN_RT_NAME="$(awk '/libclang_rt.asan/ {x=$1; exit} END {print x; exit x==""}' < <(ldd "$SYSTEMD"))"; then
         ASAN_COMPILER=clang
         ASAN_RT_PATH="$(readlink -f "$(${CC:-clang} --print-file-name "$ASAN_RT_NAME")")"
 

test/units/testsuite-17.01.sh

@@ -20,6 +20,7 @@ while : ; do
 done
 
 cat >/run/udev/rules.d/50-testsuite.rules <<EOF
+SUBSYSTEM=="block", KERNEL=="sda", OPTIONS="log_level=debug"
 ACTION!="remove", SUBSYSTEM=="block", KERNEL=="sda", ENV{SYSTEMD_WANTS}="foobar.service"
 EOF
 udevadm control --reload
@@ -37,6 +38,7 @@ while : ; do
 done
 
 cat >/run/udev/rules.d/50-testsuite.rules <<EOF
+SUBSYSTEM=="block", KERNEL=="sda", OPTIONS="log_level=debug"
 ACTION!="remove", SUBSYSTEM=="block", KERNEL=="sda", ENV{SYSTEMD_WANTS}="waldo.service"
 EOF
 udevadm control --reload

test/units/testsuite-17.02.sh

@@ -7,6 +7,7 @@ mkdir -p /run/udev/rules.d/
 cat >/run/udev/rules.d/50-testsuite.rules <<EOF
 ACTION=="remove", GOTO="lo_end"
 
+SUBSYSTEM=="net", KERNEL=="lo", OPTIONS="log_level=debug"
 SUBSYSTEM=="net", KERNEL=="lo", TAG+="systemd", ENV{SYSTEMD_ALIAS}+="/sys/subsystem/net/devices/lo"
 
 ACTION!="change", GOTO="lo_end"

test/units/testsuite-17.03.sh

@@ -7,7 +7,10 @@ test_rule="/run/udev/rules.d/49-test.rules"
 setup() {
     mkdir -p "${test_rule%/*}"
     cp -f /etc/udev/udev.conf /etc/udev/udev.conf.bckp
-    echo 'KERNEL=="lo", SUBSYSTEM=="net", PROGRAM=="/bin/sleep 60"' >"${test_rule}"
+    cat >"${test_rule}" <<EOF
+SUBSYSTEM=="net", KERNEL=="lo", OPTIONS="log_level=debug"
+SUBSYSTEM=="net", KERNEL=="lo", PROGRAM=="/bin/sleep 60"
+EOF
     echo "event_timeout=30" >>/etc/udev/udev.conf
     echo "timeout_signal=SIGABRT" >>/etc/udev/udev.conf
 

test/units/testsuite-17.04.sh

@@ -9,6 +9,7 @@ test ! -f /run/udev/tags/changed/c1:3
 udevadm info /dev/null | grep -E 'E: (TAGS|CURRENT_TAGS)=.*:(added|changed):' && exit 1
 
 cat >/run/udev/rules.d/50-testsuite.rules <<EOF
+SUBSYSTEM=="mem", KERNEL=="null", OPTIONS="log_level=debug"
 ACTION=="add", SUBSYSTEM=="mem", KERNEL=="null", TAG+="added"
 ACTION=="change", SUBSYSTEM=="mem", KERNEL=="null", TAG+="changed"
 EOF

test/units/testsuite-17.06.sh

@@ -0,0 +1,75 @@
+#!/bin/bash
+set -ex
+set -o pipefail
+
+# tests for udev watch
+
+function check_validity() {
+    local f ID_OR_HANDLE
+
+    for f in /run/udev/watch/*; do
+        ID_OR_HANDLE=$(readlink $f)
+        test -L /run/udev/watch/${ID_OR_HANDLE}
+        test $(readlink /run/udev/watch/${ID_OR_HANDLE}) = $(basename $f)
+    done
+}
+
+function check() {
+    local i j
+
+    for ((i=0;i<2;i++)); do
+        systemctl restart systemd-udevd.service
+        udevadm control --ping
+        udevadm settle
+        sleep 1
+        check_validity
+
+        for ((j=0;j<2;j++)); do
+            udevadm trigger -w --action add --subsystem-match=block
+            udevadm settle
+            sleep 1
+            check_validity
+        done
+
+        for ((j=0;j<2;j++)); do
+            udevadm trigger -w --action change --subsystem-match=block
+            udevadm settle
+            sleep 1
+            check_validity
+        done
+    done
+}
+
+mkdir -p /run/udev/rules.d/
+
+cat >/run/udev/rules.d/00-debug.rules <<EOF
+SUBSYSTEM=="block", KERNEL=="sda*", OPTIONS="log_level=debug"
+EOF
+
+cat >/run/udev/rules.d/50-testsuite.rules <<EOF
+ACTION=="add", SUBSYSTEM=="block", KERNEL=="sda", OPTIONS:="watch"
+EOF
+
+check
+
+MAJOR=$(udevadm info /dev/sda | grep -e '^E: MAJOR=' | sed -e 's/^E: MAJOR=//')
+MINOR=$(udevadm info /dev/sda | grep -e '^E: MINOR=' | sed -e 's/^E: MINOR=//')
+test -L /run/udev/watch/b${MAJOR}:${MINOR}
+
+cat >/run/udev/rules.d/50-testsuite.rules <<EOF
+ACTION=="change", SUBSYSTEM=="block", KERNEL=="sda", OPTIONS:="nowatch"
+EOF
+
+check
+
+MAJOR=$(udevadm info /dev/sda | grep -e '^E: MAJOR=' | sed -e 's/^E: MAJOR=//')
+MINOR=$(udevadm info /dev/sda | grep -e '^E: MINOR=' | sed -e 's/^E: MINOR=//')
+test ! -e /run/udev/watch/b${MAJOR}:${MINOR}
+
+rm /run/udev/rules.d/00-debug.rules
+rm /run/udev/rules.d/50-testsuite.rules
+
+udevadm control --reload
+udevadm trigger -w --action add --subsystem-match=block
+
+exit 0

test/units/testsuite-17.sh

@@ -5,6 +5,8 @@ set -o pipefail
 
 : >/failed
 
+udevadm settle
+
 for t in "${0%.sh}".*.sh; do
     echo "Running $t"; ./"$t"
 done