tree-wide: use coccinelle to patch a lot of code to use mfree()

This replaces this:

        free(p);
        p = NULL;

by this:

        p = mfree(p);

Change generated using coccinelle. Semantic patch is added to the
sources.

42 files changed, 86 insertions, 173 deletions

diff --git a/coccinelle/mfree.cocci b/coccinelle/mfree.cocci
new file mode 100644
index 0000000000..1389cd35db
--- /dev/null
+++ b/coccinelle/mfree.cocci
@@ -0,0 +1,6 @@
+@@
+expression p;
+@@
+- free(p);
+- p = NULL;
++ p = mfree(p);
diff --git a/src/analyze/analyze.c b/src/analyze/analyze.c
index ab7fb53269..e38a4340b6 100644
--- a/src/analyze/analyze.c
+++ b/src/analyze/analyze.c
@@ -582,8 +582,7 @@ static int analyze_plot(sd_bus *bus) {
 
                 if (u->activating < boot->userspace_time ||
                     u->activating > boot->finish_time) {
-                        free(u->name);
-                        u->name = NULL;
+                        u->name = mfree(u->name);
                         continue;
                 }
 
diff --git a/src/basic/bitmap.c b/src/basic/bitmap.c
index 7ea3357031..2eabf3e1c1 100644
--- a/src/basic/bitmap.c
+++ b/src/basic/bitmap.c
@@ -145,8 +145,7 @@ bool bitmap_isclear(Bitmap *b) {
 void bitmap_clear(Bitmap *b) {
         assert(b);
 
-        free(b->bitmaps);
-        b->bitmaps = NULL;
+        b->bitmaps = mfree(b->bitmaps);
         b->n_bitmaps = 0;
         b->bitmaps_allocated = 0;
 }
diff --git a/src/basic/lockfile-util.c b/src/basic/lockfile-util.c
index 05e16d1caa..f3ec6a3e52 100644
--- a/src/basic/lockfile-util.c
+++ b/src/basic/lockfile-util.c
@@ -145,8 +145,7 @@ void release_lock_file(LockFile *f) {
                 if ((f->operation & ~LOCK_NB) == LOCK_EX)
                         unlink_noerrno(f->path);
 
-                free(f->path);
-                f->path = NULL;
+                f->path = mfree(f->path);
         }
 
         f->fd = safe_close(f->fd);
diff --git a/src/basic/strv.c b/src/basic/strv.c
index eaf440a4b2..aa68d290f6 100644
--- a/src/basic/strv.c
+++ b/src/basic/strv.c
@@ -271,8 +271,7 @@ char **strv_split_newlines(const char *s) {
                 return l;
 
         if (isempty(l[n-1])) {
-                free(l[n-1]);
-                l[n-1] = NULL;
+                l[n - 1] = mfree(l[n - 1]);
         }
 
         return l;
diff --git a/src/core/automount.c b/src/core/automount.c
index b8171ddad7..5bb61b95d3 100644
--- a/src/core/automount.c
+++ b/src/core/automount.c
@@ -127,8 +127,7 @@ static void automount_done(Unit *u) {
 
         unmount_autofs(a);
 
-        free(a->where);
-        a->where = NULL;
+        a->where = mfree(a->where);
 
         set_free(a->tokens);
         a->tokens = NULL;
diff --git a/src/core/busname.c b/src/core/busname.c
index d3c1282239..4020e9dd3c 100644
--- a/src/core/busname.c
+++ b/src/core/busname.c
@@ -95,8 +95,7 @@ static void busname_done(Unit *u) {
 
         assert(n);
 
-        free(n->name);
-        n->name = NULL;
+        n->name = mfree(n->name);
 
         busname_free_policy(n);
         busname_unwatch_control_pid(n);
diff --git a/src/core/dbus-execute.c b/src/core/dbus-execute.c
index 3c98a0b186..ed55fcfca2 100644
--- a/src/core/dbus-execute.c
+++ b/src/core/dbus-execute.c
@@ -786,8 +786,7 @@ int bus_exec_context_set_transient_property(
                 if (mode != UNIT_CHECK) {
 
                         if (isempty(uu)) {
-                                free(c->user);
-                                c->user = NULL;
+                                c->user = mfree(c->user);
                         } else {
                                 char *t;
 
@@ -814,8 +813,7 @@ int bus_exec_context_set_transient_property(
                 if (mode != UNIT_CHECK) {
 
                         if (isempty(gg)) {
-                                free(c->group);
-                                c->group = NULL;
+                                c->group = mfree(c->group);
                         } else {
                                 char *t;
 
diff --git a/src/core/device.c b/src/core/device.c
index 3f574b1832..7fdfacfddf 100644
--- a/src/core/device.c
+++ b/src/core/device.c
@@ -60,8 +60,7 @@ static void device_unset_sysfs(Device *d) {
         else
                 hashmap_remove(devices, d->sysfs);
 
-        free(d->sysfs);
-        d->sysfs = NULL;
+        d->sysfs = mfree(d->sysfs);
 }
 
 static int device_set_sysfs(Device *d, const char *sysfs) {
diff --git a/src/core/execute.c b/src/core/execute.c
index 28eeeaad18..de5c16bd76 100644
--- a/src/core/execute.c
+++ b/src/core/execute.c
@@ -1994,32 +1994,20 @@ void exec_context_done(ExecContext *c) {
         c->environment_files = NULL;
 
         for (l = 0; l < ELEMENTSOF(c->rlimit); l++) {
-                free(c->rlimit[l]);
-                c->rlimit[l] = NULL;
+                c->rlimit[l] = mfree(c->rlimit[l]);
         }
 
-        free(c->working_directory);
-        c->working_directory = NULL;
-        free(c->root_directory);
-        c->root_directory = NULL;
-
-        free(c->tty_path);
-        c->tty_path = NULL;
-
-        free(c->syslog_identifier);
-        c->syslog_identifier = NULL;
-
-        free(c->user);
-        c->user = NULL;
-
-        free(c->group);
-        c->group = NULL;
+        c->working_directory = mfree(c->working_directory);
+        c->root_directory = mfree(c->root_directory);
+        c->tty_path = mfree(c->tty_path);
+        c->syslog_identifier = mfree(c->syslog_identifier);
+        c->user = mfree(c->user);
+        c->group = mfree(c->group);
 
         strv_free(c->supplementary_groups);
         c->supplementary_groups = NULL;
 
-        free(c->pam_name);
-        c->pam_name = NULL;
+        c->pam_name = mfree(c->pam_name);
 
         if (c->capabilities) {
                 cap_free(c->capabilities);
@@ -2038,14 +2026,9 @@ void exec_context_done(ExecContext *c) {
         if (c->cpuset)
                 CPU_FREE(c->cpuset);
 
-        free(c->utmp_id);
-        c->utmp_id = NULL;
-
-        free(c->selinux_context);
-        c->selinux_context = NULL;
-
-        free(c->apparmor_profile);
-        c->apparmor_profile = NULL;
+        c->utmp_id = mfree(c->utmp_id);
+        c->selinux_context = mfree(c->selinux_context);
+        c->apparmor_profile = mfree(c->apparmor_profile);
 
         set_free(c->syscall_filter);
         c->syscall_filter = NULL;
@@ -2090,8 +2073,7 @@ int exec_context_destroy_runtime_directory(ExecContext *c, const char *runtime_p
 void exec_command_done(ExecCommand *c) {
         assert(c);
 
-        free(c->path);
-        c->path = NULL;
+        c->path = mfree(c->path);
 
         strv_free(c->argv);
         c->argv = NULL;
diff --git a/src/core/load-fragment.c b/src/core/load-fragment.c
index 542bf8eb26..0299fe7603 100644
--- a/src/core/load-fragment.c
+++ b/src/core/load-fragment.c
@@ -1215,8 +1215,7 @@ int config_parse_exec_selinux_context(
         assert(data);
 
         if (isempty(rvalue)) {
-                free(c->selinux_context);
-                c->selinux_context = NULL;
+                c->selinux_context = mfree(c->selinux_context);
                 c->selinux_context_ignore = false;
                 return 0;
         }
@@ -1265,8 +1264,7 @@ int config_parse_exec_apparmor_profile(
         assert(data);
 
         if (isempty(rvalue)) {
-                free(c->apparmor_profile);
-                c->apparmor_profile = NULL;
+                c->apparmor_profile = mfree(c->apparmor_profile);
                 c->apparmor_profile_ignore = false;
                 return 0;
         }
@@ -1315,8 +1313,7 @@ int config_parse_exec_smack_process_label(
         assert(data);
 
         if (isempty(rvalue)) {
-                free(c->smack_process_label);
-                c->smack_process_label = NULL;
+                c->smack_process_label = mfree(c->smack_process_label);
                 c->smack_process_label_ignore = false;
                 return 0;
         }
@@ -3575,8 +3572,7 @@ int unit_load_fragment(Unit *u) {
                         /* Hmm, this didn't work? Then let's get rid
                          * of the fragment path stored for us, so that
                          * we don't point to an invalid location. */
-                        free(u->fragment_path);
-                        u->fragment_path = NULL;
+                        u->fragment_path = mfree(u->fragment_path);
                 }
         }
 
diff --git a/src/core/main.c b/src/core/main.c
index fe8f1924bd..091af6a9df 100644
--- a/src/core/main.c
+++ b/src/core/main.c
@@ -1843,8 +1843,7 @@ finish:
         m = manager_free(m);
 
         for (j = 0; j < ELEMENTSOF(arg_default_rlimit); j++) {
-                free(arg_default_rlimit[j]);
-                arg_default_rlimit[j] = NULL;
+                arg_default_rlimit[j] = mfree(arg_default_rlimit[j]);
         }
 
         arg_default_unit = mfree(arg_default_unit);
diff --git a/src/core/manager.c b/src/core/manager.c
index 56f2c92feb..cd0513fd69 100644
--- a/src/core/manager.c
+++ b/src/core/manager.c
@@ -674,8 +674,7 @@ static int manager_setup_notify(Manager *m) {
                 static const int one = 1;
 
                 /* First free all secondary fields */
-                free(m->notify_socket);
-                m->notify_socket = NULL;
+                m->notify_socket = mfree(m->notify_socket);
                 m->notify_event_source = sd_event_source_unref(m->notify_event_source);
 
                 fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
@@ -2794,8 +2793,7 @@ static void trim_generator_dir(Manager *m, char **generator) {
                 return;
 
         if (rmdir(*generator) >= 0) {
-                free(*generator);
-                *generator = NULL;
+                *generator = mfree(*generator);
         }
 
         return;
@@ -2866,8 +2864,7 @@ static void remove_generator_dir(Manager *m, char **generator) {
         strv_remove(m->lookup_paths.unit_path, *generator);
         (void) rm_rf(*generator, REMOVE_ROOT);
 
-        free(*generator);
-        *generator = NULL;
+        *generator = mfree(*generator);
 }
 
 static void manager_undo_generators(Manager *m) {
diff --git a/src/core/mount.c b/src/core/mount.c
index 2b81d17b9c..83746ca412 100644
--- a/src/core/mount.c
+++ b/src/core/mount.c
@@ -203,8 +203,7 @@ static void mount_done(Unit *u) {
 
         assert(m);
 
-        free(m->where);
-        m->where = NULL;
+        m->where = mfree(m->where);
 
         mount_parameters_done(&m->parameters_proc_self_mountinfo);
         mount_parameters_done(&m->parameters_fragment);
diff --git a/src/core/scope.c b/src/core/scope.c
index 35cf0621be..98395becfd 100644
--- a/src/core/scope.c
+++ b/src/core/scope.c
@@ -476,8 +476,7 @@ int scope_abandon(Scope *s) {
         if (!IN_SET(s->state, SCOPE_RUNNING, SCOPE_ABANDONED))
                 return -ESTALE;
 
-        free(s->controller);
-        s->controller = NULL;
+        s->controller = mfree(s->controller);
 
         /* The client is no longer watching the remaining processes,
          * so let's step in here, under the assumption that the
diff --git a/src/core/service.c b/src/core/service.c
index 292fe50de8..1cf1fcffdc 100644
--- a/src/core/service.c
+++ b/src/core/service.c
@@ -142,8 +142,7 @@ static void service_unwatch_pid_file(Service *s) {
         log_unit_debug(UNIT(s), "Stopping watch for PID file %s", s->pid_file_pathspec->path);
         path_spec_unwatch(s->pid_file_pathspec);
         path_spec_done(s->pid_file_pathspec);
-        free(s->pid_file_pathspec);
-        s->pid_file_pathspec = NULL;
+        s->pid_file_pathspec = mfree(s->pid_file_pathspec);
 }
 
 static int service_set_main_pid(Service *s, pid_t pid) {
@@ -287,14 +286,9 @@ static void service_done(Unit *u) {
 
         assert(s);
 
-        free(s->pid_file);
-        s->pid_file = NULL;
-
-        free(s->status_text);
-        s->status_text = NULL;
-
-        free(s->reboot_arg);
-        s->reboot_arg = NULL;
+        s->pid_file = mfree(s->pid_file);
+        s->status_text = mfree(s->status_text);
+        s->reboot_arg = mfree(s->reboot_arg);
 
         s->exec_runtime = exec_runtime_unref(s->exec_runtime);
         exec_command_free_array(s->exec_command, _SERVICE_EXEC_COMMAND_MAX);
@@ -313,8 +307,7 @@ static void service_done(Unit *u) {
 
         if (s->bus_name)  {
                 unit_unwatch_bus_name(u, s->bus_name);
-                free(s->bus_name);
-                s->bus_name = NULL;
+                s->bus_name = mfree(s->bus_name);
         }
 
         s->bus_endpoint_fd = safe_close(s->bus_endpoint_fd);
@@ -1939,8 +1932,7 @@ static int service_start(Unit *u) {
         s->forbid_restart = false;
         s->reset_cpu_usage = true;
 
-        free(s->status_text);
-        s->status_text = NULL;
+        s->status_text = mfree(s->status_text);
         s->status_errno = 0;
 
         s->notify_state = NOTIFY_UNKNOWN;
diff --git a/src/core/socket.c b/src/core/socket.c
index 1014fad626..7d3d5eb78a 100644
--- a/src/core/socket.c
+++ b/src/core/socket.c
@@ -135,11 +135,8 @@ static void socket_done(Unit *u) {
 
         unit_ref_unset(&s->service);
 
-        free(s->tcp_congestion);
-        s->tcp_congestion = NULL;
-
-        free(s->bind_to_device);
-        s->bind_to_device = NULL;
+        s->tcp_congestion = mfree(s->tcp_congestion);
+        s->bind_to_device = mfree(s->bind_to_device);
 
         free(s->smack);
         free(s->smack_ip_in);
diff --git a/src/core/swap.c b/src/core/swap.c
index 2f462e339d..a26bc58cfc 100644
--- a/src/core/swap.c
+++ b/src/core/swap.c
@@ -59,8 +59,7 @@ static void swap_unset_proc_swaps(Swap *s) {
         if (!s->from_proc_swaps)
                 return;
 
-        free(s->parameters_proc_swaps.what);
-        s->parameters_proc_swaps.what = NULL;
+        s->parameters_proc_swaps.what = mfree(s->parameters_proc_swaps.what);
 
         s->from_proc_swaps = false;
 }
@@ -87,8 +86,7 @@ static int swap_set_devnode(Swap *s, const char *devnode) {
                 else
                         hashmap_remove(swaps, s->devnode);
 
-                free(s->devnode);
-                s->devnode = NULL;
+                s->devnode = mfree(s->devnode);
         }
 
         if (devnode) {
@@ -141,14 +139,9 @@ static void swap_done(Unit *u) {
         swap_unset_proc_swaps(s);
         swap_set_devnode(s, NULL);
 
-        free(s->what);
-        s->what = NULL;
-
-        free(s->parameters_fragment.what);
-        s->parameters_fragment.what = NULL;
-
-        free(s->parameters_fragment.options);
-        s->parameters_fragment.options = NULL;
+        s->what = mfree(s->what);
+        s->parameters_fragment.what = mfree(s->parameters_fragment.what);
+        s->parameters_fragment.options = mfree(s->parameters_fragment.options);
 
         s->exec_runtime = exec_runtime_unref(s->exec_runtime);
         exec_command_done_array(s->exec_command, _SWAP_EXEC_COMMAND_MAX);
diff --git a/src/hostname/hostnamed.c b/src/hostname/hostnamed.c
index e90ae54156..e1ce2e6b31 100644
--- a/src/hostname/hostnamed.c
+++ b/src/hostname/hostnamed.c
@@ -64,8 +64,7 @@ static void context_reset(Context *c) {
         assert(c);
 
         for (p = 0; p < _PROP_MAX; p++) {
-                free(c->data[p]);
-                c->data[p] = NULL;
+                c->data[p] = mfree(c->data[p]);
         }
 }
 
@@ -498,8 +497,7 @@ static int method_set_static_hostname(sd_bus_message *m, void *userdata, sd_bus_
                 return 1; /* No authorization for now, but the async polkit stuff will call us again when it has it */
 
         if (isempty(name)) {
-                free(c->data[PROP_STATIC_HOSTNAME]);
-                c->data[PROP_STATIC_HOSTNAME] = NULL;
+                c->data[PROP_STATIC_HOSTNAME] = mfree(c->data[PROP_STATIC_HOSTNAME]);
         } else {
                 char *h;
 
@@ -570,8 +568,7 @@ static int set_machine_info(Context *c, sd_bus_message *m, int prop, sd_bus_mess
                 return 1; /* No authorization for now, but the async polkit stuff will call us again when it has it */
 
         if (isempty(name)) {
-                free(c->data[prop]);
-                c->data[prop] = NULL;
+                c->data[prop] = mfree(c->data[prop]);
         } else {
                 char *h;
 
diff --git a/src/import/export-tar.c b/src/import/export-tar.c
index 5adc748c50..43fa9d1b03 100644
--- a/src/import/export-tar.c
+++ b/src/import/export-tar.c
@@ -287,8 +287,7 @@ int tar_export_start(TarExport *e, const char *path, int fd, ImportCompressType
                 if (r >= 0)
                         e->quota_referenced = q.referenced;
 
-                free(e->temp_path);
-                e->temp_path = NULL;
+                e->temp_path = mfree(e->temp_path);
 
                 r = tempfn_random(path, NULL, &e->temp_path);
                 if (r < 0)
@@ -298,8 +297,7 @@ int tar_export_start(TarExport *e, const char *path, int fd, ImportCompressType
                 r = btrfs_subvol_snapshot_fd(sfd, e->temp_path, BTRFS_SNAPSHOT_READ_ONLY|BTRFS_SNAPSHOT_RECURSIVE);
                 if (r < 0) {
                         log_debug_errno(r, "Couldn't create snapshot %s of %s, not exporting atomically: %m", e->temp_path, path);
-                        free(e->temp_path);
-                        e->temp_path = NULL;
+                        e->temp_path = mfree(e->temp_path);
                 }
         }
 
diff --git a/src/import/import-raw.c b/src/import/import-raw.c
index a27e81bbd4..5f7d25d063 100644
--- a/src/import/import-raw.c
+++ b/src/import/import-raw.c
@@ -249,8 +249,7 @@ static int raw_import_finish(RawImport *i) {
         if (r < 0)
                 return log_error_errno(r, "Failed to move image into place: %m");
 
-        free(i->temp_path);
-        i->temp_path = NULL;
+        i->temp_path = mfree(i->temp_path);
 
         return 0;
 }
diff --git a/src/import/import-tar.c b/src/import/import-tar.c
index 7ffe83cc33..d2bfb30238 100644
--- a/src/import/import-tar.c
+++ b/src/import/import-tar.c
@@ -205,8 +205,7 @@ static int tar_import_finish(TarImport *i) {
         if (r < 0)
                 return log_error_errno(r, "Failed to move image into place: %m");
 
-        free(i->temp_path);
-        i->temp_path = NULL;
+        i->temp_path = mfree(i->temp_path);
 
         return 0;
 }
diff --git a/src/import/pull-dkr.c b/src/import/pull-dkr.c
index 5ff49baa22..0dab184af1 100644
--- a/src/import/pull-dkr.c
+++ b/src/import/pull-dkr.c
@@ -1211,10 +1211,8 @@ static void dkr_pull_job_on_finished(PullJob *j) {
                 log_info("Completed writing to layer %s.", i->final_path);
 
                 i->layer_job = pull_job_unref(i->layer_job);
-                free(i->temp_path);
-                i->temp_path = NULL;
-                free(i->final_path);
-                i->final_path = NULL;
+                i->temp_path = mfree(i->temp_path);
+                i->final_path = mfree(i->final_path);
 
                 i->current_ancestry ++;
                 r = dkr_pull_pull_layer(i);
diff --git a/src/journal-remote/journal-gatewayd.c b/src/journal-remote/journal-gatewayd.c
index ebdd9edfc3..52078b1b37 100644
--- a/src/journal-remote/journal-gatewayd.c
+++ b/src/journal-remote/journal-gatewayd.c
@@ -338,8 +338,7 @@ static int request_parse_range(
 
         m->cursor[strcspn(m->cursor, WHITESPACE)] = 0;
         if (isempty(m->cursor)) {
-                free(m->cursor);
-                m->cursor = NULL;
+                m->cursor = mfree(m->cursor);
         }
 
         return 0;
diff --git a/src/journal-remote/journal-remote-write.c b/src/journal-remote/journal-remote-write.c
index 99820fa7b8..40f4ff8e58 100644
--- a/src/journal-remote/journal-remote-write.c
+++ b/src/journal-remote/journal-remote-write.c
@@ -30,8 +30,7 @@ int iovw_put(struct iovec_wrapper *iovw, void* data, size_t len) {
 }
 
 void iovw_free_contents(struct iovec_wrapper *iovw) {
-        free(iovw->iovec);
-        iovw->iovec = NULL;
+        iovw->iovec = mfree(iovw->iovec);
         iovw->size_bytes = iovw->count = 0;
 }
 
diff --git a/src/journal-remote/journal-upload-journal.c b/src/journal-remote/journal-upload-journal.c
index 5fd639a76a..3d2e52cacf 100644
--- a/src/journal-remote/journal-upload-journal.c
+++ b/src/journal-remote/journal-upload-journal.c
@@ -21,8 +21,7 @@ static ssize_t write_entry(char *buf, size_t size, Uploader *u) {
 
                 switch(u->entry_state) {
                 case ENTRY_CURSOR: {
-                        free(u->current_cursor);
-                        u->current_cursor = NULL;
+                        u->current_cursor = mfree(u->current_cursor);
 
                         r = sd_journal_get_cursor(u->journal, &u->current_cursor);
                         if (r < 0)
diff --git a/src/libsystemd/sd-bus/bus-creds.c b/src/libsystemd/sd-bus/bus-creds.c
index c3cc2b7212..99b9aa8084 100644
--- a/src/libsystemd/sd-bus/bus-creds.c
+++ b/src/libsystemd/sd-bus/bus-creds.c
@@ -107,8 +107,7 @@ _public_ sd_bus_creds *sd_bus_creds_unref(sd_bus_creds *c) {
                         free(c->cgroup_root);
                         free(c->description);
 
-                        free(c->supplementary_gids);
-                        c->supplementary_gids = NULL;
+                        c->supplementary_gids = mfree(c->supplementary_gids);
 
                         strv_free(c->well_known_names);
                         c->well_known_names = NULL;
@@ -1016,8 +1015,7 @@ int bus_creds_add_more(sd_bus_creds *c, uint64_t mask, pid_t pid, pid_t tid) {
                                 return r;
                 } else {
                         if (c->cmdline_size == 0) {
-                                free(c->cmdline);
-                                c->cmdline = NULL;
+                                c->cmdline = mfree(c->cmdline);
                         }
 
                         c->mask |= SD_BUS_CREDS_CMDLINE;
diff --git a/src/libsystemd/sd-bus/bus-message.c b/src/libsystemd/sd-bus/bus-message.c
index 366a026426..72e2b9f785 100644
--- a/src/libsystemd/sd-bus/bus-message.c
+++ b/src/libsystemd/sd-bus/bus-message.c
@@ -113,8 +113,7 @@ static void message_reset_containers(sd_bus_message *m) {
                 free(m->containers[i].offsets);
         }
 
-        free(m->containers);
-        m->containers = NULL;
+        m->containers = mfree(m->containers);
 
         m->n_containers = m->containers_allocated = 0;
         m->root_container.index = 0;
diff --git a/src/libsystemd/sd-bus/busctl-introspect.c b/src/libsystemd/sd-bus/busctl-introspect.c
index 03e83d08a1..abe482fc46 100644
--- a/src/libsystemd/sd-bus/busctl-introspect.c
+++ b/src/libsystemd/sd-bus/busctl-introspect.c
@@ -55,8 +55,7 @@ static void context_reset_member(Context *c) {
 }
 
 static void context_reset_interface(Context *c) {
-        free(c->interface_name);
-        c->interface_name = NULL;
+        c->interface_name = mfree(c->interface_name);
         c->interface_flags = 0;
 
         context_reset_member(c);
diff --git a/src/libsystemd/sd-bus/sd-bus.c b/src/libsystemd/sd-bus/sd-bus.c
index 4a9181613a..2ac4b9be8e 100644
--- a/src/libsystemd/sd-bus/sd-bus.c
+++ b/src/libsystemd/sd-bus/sd-bus.c
@@ -820,8 +820,7 @@ static int parse_container_unix_address(sd_bus *b, const char **p, char **guid)
                 b->machine = machine;
                 machine = NULL;
         } else {
-                free(b->machine);
-                b->machine = NULL;
+                b->machine = mfree(b->machine);
         }
 
         if (pid) {
@@ -880,8 +879,7 @@ static int parse_container_kernel_address(sd_bus *b, const char **p, char **guid
                 b->machine = machine;
                 machine = NULL;
         } else {
-                free(b->machine);
-                b->machine = NULL;
+                b->machine = mfree(b->machine);
         }
 
         if (pid) {
diff --git a/src/libsystemd/sd-netlink/netlink-message.c b/src/libsystemd/sd-netlink/netlink-message.c
index aee2ced2d9..e2a10ae2b4 100644
--- a/src/libsystemd/sd-netlink/netlink-message.c
+++ b/src/libsystemd/sd-netlink/netlink-message.c
@@ -843,8 +843,7 @@ int sd_netlink_message_exit_container(sd_netlink_message *m) {
         assert_return(m->sealed, -EINVAL);
         assert_return(m->n_containers > 0, -EINVAL);
 
-        free(m->containers[m->n_containers].attributes);
-        m->containers[m->n_containers].attributes = NULL;
+        m->containers[m->n_containers].attributes = mfree(m->containers[m->n_containers].attributes);
         m->containers[m->n_containers].type_system = NULL;
 
         m->n_containers --;
@@ -894,8 +893,7 @@ int sd_netlink_message_rewind(sd_netlink_message *m) {
                 rtnl_message_seal(m);
 
         for (i = 1; i <= m->n_containers; i++) {
-                free(m->containers[i].attributes);
-                m->containers[i].attributes = NULL;
+                m->containers[i].attributes = mfree(m->containers[i].attributes);
         }
 
         m->n_containers = 0;
diff --git a/src/libudev/libudev-list.c b/src/libudev/libudev-list.c
index 044ee3a0cb..19e9130be0 100644
--- a/src/libudev/libudev-list.c
+++ b/src/libudev/libudev-list.c
@@ -246,8 +246,7 @@ void udev_list_cleanup(struct udev_list *list)
         struct udev_list_entry *entry_loop;
         struct udev_list_entry *entry_tmp;
 
-        free(list->entries);
-        list->entries = NULL;
+        list->entries = mfree(list->entries);
         list->entries_cur = 0;
         list->entries_max = 0;
         udev_list_entry_foreach_safe(entry_loop, entry_tmp, udev_list_get_entry(list))
diff --git a/src/login/logind-dbus.c b/src/login/logind-dbus.c
index b6fa50aa52..050d0252ad 100644
--- a/src/login/logind-dbus.c
+++ b/src/login/logind-dbus.c
@@ -1987,8 +1987,7 @@ static int method_cancel_scheduled_shutdown(sd_bus_message *message, void *userd
         m->scheduled_shutdown_timeout_source = sd_event_source_unref(m->scheduled_shutdown_timeout_source);
         m->wall_message_timeout_source = sd_event_source_unref(m->wall_message_timeout_source);
         m->nologin_timeout_source = sd_event_source_unref(m->nologin_timeout_source);
-        free(m->scheduled_shutdown_type);
-        m->scheduled_shutdown_type = NULL;
+        m->scheduled_shutdown_type = mfree(m->scheduled_shutdown_type);
         m->scheduled_shutdown_timeout = 0;
 
         if (m->unlink_nologin) {
diff --git a/src/login/logind-inhibit.c b/src/login/logind-inhibit.c
index cfae186edd..0c9c1e5e97 100644
--- a/src/login/logind-inhibit.c
+++ b/src/login/logind-inhibit.c
@@ -333,8 +333,7 @@ void inhibitor_remove_fifo(Inhibitor *i) {
 
         if (i->fifo_path) {
                 unlink(i->fifo_path);
-                free(i->fifo_path);
-                i->fifo_path = NULL;
+                i->fifo_path = mfree(i->fifo_path);
         }
 }
 
diff --git a/src/login/logind-session.c b/src/login/logind-session.c
index 92a6027a7e..d2c5a29801 100644
--- a/src/login/logind-session.c
+++ b/src/login/logind-session.c
@@ -913,8 +913,7 @@ static void session_remove_fifo(Session *s) {
 
         if (s->fifo_path) {
                 unlink(s->fifo_path);
-                free(s->fifo_path);
-                s->fifo_path = NULL;
+                s->fifo_path = mfree(s->fifo_path);
         }
 }
 
diff --git a/src/login/logind-user.c b/src/login/logind-user.c
index 5d8a7571cd..f2c89e3653 100644
--- a/src/login/logind-user.c
+++ b/src/login/logind-user.c
@@ -560,8 +560,7 @@ static int user_remove_runtime_path(User *u) {
         if (r < 0)
                 log_error_errno(r, "Failed to remove runtime directory %s: %m", u->runtime_path);
 
-        free(u->runtime_path);
-        u->runtime_path = NULL;
+        u->runtime_path = mfree(u->runtime_path);
 
         return r;
 }
diff --git a/src/machine/machine.c b/src/machine/machine.c
index a056ec3b08..b52ecd015c 100644
--- a/src/machine/machine.c
+++ b/src/machine/machine.c
@@ -600,8 +600,7 @@ void machine_release_unit(Machine *m) {
                 return;
 
         (void) hashmap_remove(m->manager->machine_units, m->unit);
-        free(m->unit);
-        m->unit = NULL;
+        m->unit = mfree(m->unit);
 }
 
 static const char* const machine_class_table[_MACHINE_CLASS_MAX] = {
diff --git a/src/network/networkd-netdev-tuntap.c b/src/network/networkd-netdev-tuntap.c
index ba84e802fc..6a808b6205 100644
--- a/src/network/networkd-netdev-tuntap.c
+++ b/src/network/networkd-netdev-tuntap.c
@@ -143,11 +143,8 @@ static void tuntap_done(NetDev *netdev) {
 
         assert(t);
 
-        free(t->user_name);
-        t->user_name = NULL;
-
-        free(t->group_name);
-        t->group_name = NULL;
+        t->user_name = mfree(t->user_name);
+        t->group_name = mfree(t->group_name);
 }
 
 static int tuntap_verify(NetDev *netdev, const char *filename) {
diff --git a/src/network/networkd-wait-online-link.c b/src/network/networkd-wait-online-link.c
index 2d5123788c..cacb4c257e 100644
--- a/src/network/networkd-wait-online-link.c
+++ b/src/network/networkd-wait-online-link.c
@@ -120,13 +120,11 @@ int link_update_rtnl(Link *l, sd_netlink_message *m) {
 int link_update_monitor(Link *l) {
         assert(l);
 
-        free(l->operational_state);
-        l->operational_state = NULL;
+        l->operational_state = mfree(l->operational_state);
 
         sd_network_link_get_operational_state(l->ifindex, &l->operational_state);
 
-        free(l->state);
-        l->state = NULL;
+        l->state = mfree(l->state);
 
         sd_network_link_get_setup_state(l->ifindex, &l->state);
 
diff --git a/src/shared/bus-util.c b/src/shared/bus-util.c
index d9cc19700e..36c44227c5 100644
--- a/src/shared/bus-util.c
+++ b/src/shared/bus-util.c
@@ -1884,11 +1884,8 @@ int bus_wait_for_jobs(BusWaitForJobs *d, bool quiet) {
                         log_debug_errno(q, "Got result %s/%m for job %s", strna(d->result), strna(d->name));
                 }
 
-                free(d->name);
-                d->name = NULL;
-
-                free(d->result);
-                d->result = NULL;
+                d->name = mfree(d->name);
+                d->result = mfree(d->result);
         }
 
         return r;
diff --git a/src/shared/conf-parser.c b/src/shared/conf-parser.c
index 36150d8744..23512f0d35 100644
--- a/src/shared/conf-parser.c
+++ b/src/shared/conf-parser.c
@@ -232,8 +232,7 @@ static int parse_line(const char* unit,
                                            "Unknown section '%s'. Ignoring.", n);
 
                         free(n);
-                        free(*section);
-                        *section = NULL;
+                        *section = mfree(*section);
                         *section_line = 0;
                         *section_ignored = true;
                 } else {
diff --git a/src/udev/udev-rules.c b/src/udev/udev-rules.c
index 43255fb9d4..62e21e13a7 100644
--- a/src/udev/udev-rules.c
+++ b/src/udev/udev-rules.c
@@ -1686,12 +1686,10 @@ struct udev_rules *udev_rules_new(struct udev *udev, int resolve_names) {
         strbuf_complete(rules->strbuf);
 
         /* cleanup uid/gid cache */
-        free(rules->uids);
-        rules->uids = NULL;
+        rules->uids = mfree(rules->uids);
         rules->uids_cur = 0;
         rules->uids_max = 0;
-        free(rules->gids);
-        rules->gids = NULL;
+        rules->gids = mfree(rules->gids);
         rules->gids_cur = 0;
         rules->gids_max = 0;
 
@@ -2064,8 +2062,7 @@ int udev_rules_apply_to_event(struct udev_rules *rules,
                         char program[UTIL_PATH_SIZE];
                         char result[UTIL_LINE_SIZE];
 
-                        free(event->program_result);
-                        event->program_result = NULL;
+                        event->program_result = mfree(event->program_result);
                         udev_event_apply_format(event, rules_str(rules, cur->key.value_off), program, sizeof(program));
                         log_debug("PROGRAM '%s' %s:%u",
                                   program,