tree-wide: fix memory leaks in users of bus_map_all_properties()

If you use bus_map_all_properties(), you must be aware that it might
touch output variables even though it may fail. This is, because we parse
many different bus-properties and cannot tell how to clean them up, in
case we fail deep down in the parser.

Fix all callers of bus_map_all_properties() to correctly cleanup any
context structures at all times.

src/locale/localectl.c

@@ -69,14 +69,27 @@ static void polkit_agent_open_if_enabled(void) {
 
 typedef struct StatusInfo {
         char **locale;
-        const char *vconsole_keymap;
-        const char *vconsole_keymap_toggle;
-        const char *x11_layout;
-        const char *x11_model;
-        const char *x11_variant;
-        const char *x11_options;
+        char *vconsole_keymap;
+        char *vconsole_keymap_toggle;
+        char *x11_layout;
+        char *x11_model;
+        char *x11_variant;
+        char *x11_options;
 } StatusInfo;
 
+static void status_info_clear(StatusInfo *info) {
+        if (info) {
+                strv_free(info->locale);
+                free(info->vconsole_keymap);
+                free(info->vconsole_keymap_toggle);
+                free(info->x11_layout);
+                free(info->x11_model);
+                free(info->x11_variant);
+                free(info->x11_options);
+                zero(*info);
+        }
+}
+
 static void print_overridden_variables(void) {
         int r;
         char *variables[_VARIABLE_LC_MAX] = {};
@@ -150,7 +163,7 @@ static void print_status_info(StatusInfo *i) {
 }
 
 static int show_status(sd_bus *bus, char **args, unsigned n) {
-        StatusInfo info = {};
+        _cleanup_(status_info_clear) StatusInfo info = {};
         static const struct bus_properties_map map[]  = {
                 { "VConsoleKeymap",       "s",  NULL, offsetof(StatusInfo, vconsole_keymap) },
                 { "VConsoleKeymap",       "s",  NULL, offsetof(StatusInfo, vconsole_keymap) },
@@ -171,16 +184,12 @@ static int show_status(sd_bus *bus, char **args, unsigned n) {
                                    "/org/freedesktop/locale1",
                                    map,
                                    &info);
-        if (r < 0) {
-                log_error_errno(r, "Could not get properties: %m");
-                goto fail;
-        }
+        if (r < 0)
+                return log_error_errno(r, "Could not get properties: %m");
 
         print_overridden_variables();
         print_status_info(&info);
 
-fail:
-        strv_free(info.locale);
         return r;
 }
 

src/login/loginctl.c

@@ -277,42 +277,81 @@ static int show_unit_cgroup(sd_bus *bus, const char *interface, const char *unit
 }
 
 typedef struct SessionStatusInfo {
-        const char *id;
+        char *id;
         uid_t uid;
-        const char *name;
+        char *name;
         struct dual_timestamp timestamp;
         unsigned int vtnr;
-        const char *seat;
-        const char *tty;
-        const char *display;
+        char *seat;
+        char *tty;
+        char *display;
         bool remote;
-        const char *remote_host;
-        const char *remote_user;
-        const char *service;
+        char *remote_host;
+        char *remote_user;
+        char *service;
         pid_t leader;
-        const char *type;
-        const char *class;
-        const char *state;
-        const char *scope;
-        const char *desktop;
+        char *type;
+        char *class;
+        char *state;
+        char *scope;
+        char *desktop;
 } SessionStatusInfo;
 
 typedef struct UserStatusInfo {
         uid_t uid;
-        const char *name;
+        char *name;
         struct dual_timestamp timestamp;
-        const char *state;
+        char *state;
         char **sessions;
-        const char *display;
-        const char *slice;
+        char *display;
+        char *slice;
 } UserStatusInfo;
 
 typedef struct SeatStatusInfo {
-        const char *id;
-        const char *active_session;
+        char *id;
+        char *active_session;
         char **sessions;
 } SeatStatusInfo;
 
+static void session_status_info_clear(SessionStatusInfo *info) {
+        if (info) {
+                free(info->id);
+                free(info->name);
+                free(info->seat);
+                free(info->tty);
+                free(info->display);
+                free(info->remote_host);
+                free(info->remote_user);
+                free(info->service);
+                free(info->type);
+                free(info->class);
+                free(info->state);
+                free(info->scope);
+                free(info->desktop);
+                zero(*info);
+        }
+}
+
+static void user_status_info_clear(UserStatusInfo *info) {
+        if (info) {
+                free(info->name);
+                free(info->state);
+                strv_free(info->sessions);
+                free(info->display);
+                free(info->slice);
+                zero(*info);
+        }
+}
+
+static void seat_status_info_clear(SeatStatusInfo *info) {
+        if (info) {
+                free(info->id);
+                free(info->active_session);
+                strv_free(info->sessions);
+                zero(*info);
+        }
+}
+
 static int prop_map_first_of_struct(sd_bus *bus, const char *member, sd_bus_message *m, sd_bus_error *error, void *userdata) {
         const char *contents;
         int r;
@@ -404,7 +443,7 @@ static int print_session_status_info(sd_bus *bus, const char *path, bool *new_li
 
         char since1[FORMAT_TIMESTAMP_RELATIVE_MAX], *s1;
         char since2[FORMAT_TIMESTAMP_MAX], *s2;
-        SessionStatusInfo i = {};
+        _cleanup_(session_status_info_clear) SessionStatusInfo i = {};
         int r;
 
         r = bus_map_all_properties(bus, "org.freedesktop.login1", path, map, &i);
@@ -532,14 +571,12 @@ static int print_user_status_info(sd_bus *bus, const char *path, bool *new_line)
 
         char since1[FORMAT_TIMESTAMP_RELATIVE_MAX], *s1;
         char since2[FORMAT_TIMESTAMP_MAX], *s2;
-        UserStatusInfo i = {};
+        _cleanup_(user_status_info_clear) UserStatusInfo i = {};
         int r;
 
         r = bus_map_all_properties(bus, "org.freedesktop.login1", path, map, &i);
-        if (r < 0) {
-                log_error_errno(r, "Could not get properties: %m");
-                goto finish;
-        }
+        if (r < 0)
+                return log_error_errno(r, "Could not get properties: %m");
 
         if (*new_line)
                 printf("\n");
@@ -594,10 +631,7 @@ static int print_user_status_info(sd_bus *bus, const char *path, bool *new_line)
                                 NULL);
         }
 
-finish:
-        strv_free(i.sessions);
-
-        return r;
+        return 0;
 }
 
 static int print_seat_status_info(sd_bus *bus, const char *path, bool *new_line) {
@@ -609,14 +643,12 @@ static int print_seat_status_info(sd_bus *bus, const char *path, bool *new_line)
                 {}
         };
 
-        SeatStatusInfo i = {};
+        _cleanup_(seat_status_info_clear) SeatStatusInfo i = {};
         int r;
 
         r = bus_map_all_properties(bus, "org.freedesktop.login1", path, map, &i);
-        if (r < 0) {
-                log_error_errno(r, "Could not get properties: %m");
-                goto finish;
-        }
+        if (r < 0)
+                return log_error_errno(r, "Could not get properties: %m");
 
         if (*new_line)
                 printf("\n");
@@ -653,10 +685,7 @@ static int print_seat_status_info(sd_bus *bus, const char *path, bool *new_line)
                 show_sysfs(i.id, "\t\t  ", c);
         }
 
-finish:
-        strv_free(i.sessions);
-
-        return r;
+        return 0;
 }
 
 static int show_properties(sd_bus *bus, const char *path, bool *new_line) {

src/machine/machinectl.c

@@ -500,6 +500,18 @@ typedef struct MachineStatusInfo {
         unsigned n_netif;
 } MachineStatusInfo;
 
+static void machine_status_info_clear(MachineStatusInfo *info) {
+        if (info) {
+                free(info->name);
+                free(info->class);
+                free(info->service);
+                free(info->unit);
+                free(info->root_directory);
+                free(info->netif);
+                zero(*info);
+        }
+}
+
 static void print_machine_status_info(sd_bus *bus, MachineStatusInfo *i) {
         char since1[FORMAT_TIMESTAMP_RELATIVE_MAX], *s1;
         char since2[FORMAT_TIMESTAMP_MAX], *s2;
@@ -636,7 +648,7 @@ static int show_machine_info(const char *verb, sd_bus *bus, const char *path, bo
                 {}
         };
 
-        MachineStatusInfo info = {};
+        _cleanup_(machine_status_info_clear) MachineStatusInfo info = {};
         int r;
 
         assert(verb);
@@ -658,13 +670,6 @@ static int show_machine_info(const char *verb, sd_bus *bus, const char *path, bo
 
         print_machine_status_info(bus, &info);
 
-        free(info.name);
-        free(info.class);
-        free(info.service);
-        free(info.unit);
-        free(info.root_directory);
-        free(info.netif);
-
         return r;
 }
 
@@ -753,6 +758,15 @@ typedef struct ImageStatusInfo {
         uint64_t limit_exclusive;
 } ImageStatusInfo;
 
+static void image_status_info_clear(ImageStatusInfo *info) {
+        if (info) {
+                free(info->name);
+                free(info->path);
+                free(info->type);
+                zero(*info);
+        }
+}
+
 static void print_image_status_info(sd_bus *bus, ImageStatusInfo *i) {
         char ts_relative[FORMAT_TIMESTAMP_RELATIVE_MAX], *s1;
         char ts_absolute[FORMAT_TIMESTAMP_MAX], *s2;
@@ -823,7 +837,7 @@ static int show_image_info(sd_bus *bus, const char *path, bool *new_line) {
                 {}
         };
 
-        ImageStatusInfo info = {};
+        _cleanup_(image_status_info_clear) ImageStatusInfo info = {};
         int r;
 
         assert(bus);
@@ -844,10 +858,6 @@ static int show_image_info(sd_bus *bus, const char *path, bool *new_line) {
 
         print_image_status_info(bus, &info);
 
-        free(info.name);
-        free(info.path);
-        free(info.type);
-
         return r;
 }
 
@@ -857,6 +867,15 @@ typedef struct PoolStatusInfo {
         uint64_t limit;
 } PoolStatusInfo;
 
+static void pool_status_info_clear(PoolStatusInfo *info) {
+        if (info) {
+                free(info->path);
+                zero(*info);
+                info->usage = -1;
+                info->limit = -1;
+        }
+}
+
 static void print_pool_status_info(sd_bus *bus, PoolStatusInfo *i) {
         char bs[FORMAT_BYTES_MAX], *s;
 
@@ -881,7 +900,7 @@ static int show_pool_info(sd_bus *bus) {
                 {}
         };
 
-        PoolStatusInfo info = {
+        _cleanup_(pool_status_info_clear) PoolStatusInfo info = {
                 .usage = (uint64_t) -1,
                 .limit = (uint64_t) -1,
         };
@@ -899,7 +918,6 @@ static int show_pool_info(sd_bus *bus) {
 
         print_pool_status_info(bus, &info);
 
-        free(info.path);
         return 0;
 }
 

src/systemctl/systemctl.c

@@ -1678,17 +1678,23 @@ static const struct bus_properties_map machine_info_property_map[] = {
         {}
 };
 
+static void machine_info_clear(struct machine_info *info) {
+        if (info) {
+                free(info->name);
+                free(info->state);
+                free(info->control_group);
+                zero(*info);
+        }
+}
+
 static void free_machines_list(struct machine_info *machine_infos, int n) {
         int i;
 
         if (!machine_infos)
                 return;
 
-        for (i = 0; i < n; i++) {
-                free(machine_infos[i].name);
-                free(machine_infos[i].state);
-                free(machine_infos[i].control_group);
-        }
+        for (i = 0; i < n; i++)
+                machine_info_clear(&machine_infos[i]);
 
         free(machine_infos);
 }
@@ -4402,7 +4408,7 @@ static int show_all(
 static int show_system_status(sd_bus *bus) {
         char since1[FORMAT_TIMESTAMP_RELATIVE_MAX], since2[FORMAT_TIMESTAMP_MAX];
         _cleanup_free_ char *hn = NULL;
-        struct machine_info mi = {};
+        _cleanup_(machine_info_clear) struct machine_info mi = {};
         const char *on, *off;
         int r;
 
@@ -4449,9 +4455,6 @@ static int show_system_status(sd_bus *bus) {
                 show_cgroup(SYSTEMD_CGROUP_CONTROLLER, strempty(mi.control_group), prefix, c, false, get_output_flags());
         }
 
-        free(mi.state);
-        free(mi.control_group);
-
         return 0;
 }
 

src/timedate/timedatectl.c

@@ -73,6 +73,13 @@ typedef struct StatusInfo {
         bool ntp_synced;
 } StatusInfo;
 
+static void status_info_clear(StatusInfo *info) {
+        if (info) {
+                free(info->timezone);
+                zero(*info);
+        }
+}
+
 static void print_status_info(const StatusInfo *i) {
         char a[FORMAT_TIMESTAMP_MAX];
         struct tm tm;
@@ -155,7 +162,7 @@ static void print_status_info(const StatusInfo *i) {
 }
 
 static int show_status(sd_bus *bus, char **args, unsigned n) {
-        StatusInfo info = {};
+        _cleanup_(status_info_clear) StatusInfo info = {};
         static const struct bus_properties_map map[]  = {
                 { "Timezone",        "s", NULL, offsetof(StatusInfo, timezone) },
                 { "LocalRTC",        "b", NULL, offsetof(StatusInfo, rtc_local) },
@@ -175,15 +182,11 @@ static int show_status(sd_bus *bus, char **args, unsigned n) {
                                    "/org/freedesktop/timedate1",
                                    map,
                                    &info);
-        if (r < 0) {
-                log_error_errno(r, "Failed to query server: %m");
-                goto fail;
-        }
+        if (r < 0)
+                return log_error_errno(r, "Failed to query server: %m");
 
         print_status_info(&info);
 
-fail:
-        free(info.timezone);
         return r;
 }