← Back to branch summary

~ubuntu-branches/debian/jessie/systemd/jessie

« back to all changes in this revision

Viewing changes to src/login/logind-session-dbus.c

  • Committer: Package Import Robot
  • Author(s): Tollef Fog Heen, Tollef Fog Heen, Michael Biebl
  • Date: 2012-04-03 19:59:17 UTC
  • mfrom: (1.1.10) (6.1.3 experimental)
  • Revision ID: package-import@ubuntu.com-20120403195917-l532urrbg4pkreas
Tags: 44-1
http://bugs.debian.org/664364
http://bugs.debian.org/663219
http://bugs.debian.org/663323
[ Tollef Fog Heen ]
* New upstream version.
  - Backport 3492207: journal: PAGE_SIZE is not known on ppc and other
    archs
  - Backport 5a2a2a1: journal: react with immediate rotation to a couple
    of more errors
  - Backport 693ce21: util: never follow symlinks in rm_rf_children()
    Fixes CVE-2012-1174, closes: #664364
* Drop output message from init-functions hook, it's pointless.
* Only rmdir /lib/init/rw if it exists.
* Explicitly order debian-fixup before sysinit.target to prevent a
  possible race condition with the creation of sockets.  Thanks to
  Michael Biebl for debugging this.
* Always restart the initctl socket on upgrades, to mask sysvinit
  removing it.

[ Michael Biebl ]
* Remove workaround for non-interactive sessions from pam config again.
* Create compat /dev/initctl symlink in case we are upgrading from a system
  running a newer version of sysvinit (using /run/initctl) and sysvinit is
  replaced with systemd-sysv during the upgrade. Closes: #663219
* Install new man pages.
* Build-Depend on valac (>= 0.12) instead of valac-0.12. Closes: #663323

Show diffs side-by-side

added added

removed removed

Lines of Context:
src/login/logind-session-dbus.c
 
1
/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
 
2
 
 
3
/***
 
4
  This file is part of systemd.
 
5
 
 
6
  Copyright 2011 Lennart Poettering
 
7
 
 
8
  systemd is free software; you can redistribute it and/or modify it
 
9
  under the terms of the GNU General Public License as published by
 
10
  the Free Software Foundation; either version 2 of the License, or
 
11
  (at your option) any later version.
 
12
 
 
13
  systemd is distributed in the hope that it will be useful, but
 
14
  WITHOUT ANY WARRANTY; without even the implied warranty of
 
15
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 
16
  General Public License for more details.
 
17
 
 
18
  You should have received a copy of the GNU General Public License
 
19
  along with systemd; If not, see <http://www.gnu.org/licenses/>.
 
20
***/
 
21
 
 
22
#include <errno.h>
 
23
#include <string.h>
 
24
 
 
25
#include "logind.h"
 
26
#include "logind-session.h"
 
27
#include "dbus-common.h"
 
28
#include "util.h"
 
29
 
 
30
#define BUS_SESSION_INTERFACE \
 
31
        " <interface name=\"org.freedesktop.login1.Session\">\n"        \
 
32
        "  <method name=\"Terminate\"/>\n"                              \
 
33
        "  <method name=\"Activate\"/>\n"                               \
 
34
        "  <method name=\"Lock\"/>\n"                                   \
 
35
        "  <method name=\"Unlock\"/>\n"                                 \
 
36
        "  <method name=\"SetIdleHint\">\n"                             \
 
37
        "   <arg name=\"b\" type=\"b\"/>\n"                             \
 
38
        "  </method>\n"                                                 \
 
39
        "  <method name=\"Kill\">\n"                                    \
 
40
        "   <arg name=\"who\" type=\"s\"/>\n"                           \
 
41
        "   <arg name=\"signal\" type=\"s\"/>\n"                        \
 
42
        "  </method>\n"                                                 \
 
43
        "  <property name=\"Id\" type=\"s\" access=\"read\"/>\n"        \
 
44
        "  <property name=\"User\" type=\"(uo)\" access=\"read\"/>\n"   \
 
45
        "  <property name=\"Name\" type=\"s\" access=\"read\"/>\n"      \
 
46
        "  <property name=\"Timestamp\" type=\"t\" access=\"read\"/>\n" \
 
47
        "  <property name=\"TimestampMonotonic\" type=\"t\" access=\"read\"/>\n" \
 
48
        "  <property name=\"ControlGroupPath\" type=\"s\" access=\"read\"/>\n" \
 
49
        "  <property name=\"VTNr\" type=\"u\" access=\"read\"/>\n"      \
 
50
        "  <property name=\"Seat\" type=\"(so)\" access=\"read\"/>\n"   \
 
51
        "  <property name=\"TTY\" type=\"s\" access=\"read\"/>\n"       \
 
52
        "  <property name=\"Display\" type=\"s\" access=\"read\"/>\n"   \
 
53
        "  <property name=\"Remote\" type=\"b\" access=\"read\"/>\n"    \
 
54
        "  <property name=\"RemoteHost\" type=\"s\" access=\"read\"/>\n" \
 
55
        "  <property name=\"RemoteUser\" type=\"s\" access=\"read\"/>\n" \
 
56
        "  <property name=\"Service\" type=\"s\" access=\"read\"/>\n" \
 
57
        "  <property name=\"Leader\" type=\"u\" access=\"read\"/>\n"    \
 
58
        "  <property name=\"Audit\" type=\"u\" access=\"read\"/>\n"     \
 
59
        "  <property name=\"Type\" type=\"s\" access=\"read\"/>\n"      \
 
60
        "  <property name=\"Class\" type=\"s\" access=\"read\"/>\n"      \
 
61
        "  <property name=\"Active\" type=\"b\" access=\"read\"/>\n"    \
 
62
        "  <property name=\"Controllers\" type=\"as\" access=\"read\"/>\n" \
 
63
        "  <property name=\"ResetControllers\" type=\"as\" access=\"read\"/>\n" \
 
64
        "  <property name=\"KillProcesses\" type=\"b\" access=\"read\"/>\n" \
 
65
        "  <property name=\"IdleHint\" type=\"b\" access=\"read\"/>\n"  \
 
66
        "  <property name=\"IdleSinceHint\" type=\"t\" access=\"read\"/>\n" \
 
67
        "  <property name=\"IdleSinceHintMonotonic\" type=\"t\" access=\"read\"/>\n" \
 
68
        " </interface>\n"
 
69
 
 
70
#define INTROSPECTION                                                   \
 
71
        DBUS_INTROSPECT_1_0_XML_DOCTYPE_DECL_NODE                       \
 
72
        "<node>\n"                                                      \
 
73
        BUS_SESSION_INTERFACE                                           \
 
74
        BUS_PROPERTIES_INTERFACE                                        \
 
75
        BUS_PEER_INTERFACE                                              \
 
76
        BUS_INTROSPECTABLE_INTERFACE                                    \
 
77
        "</node>\n"
 
78
 
 
79
#define INTERFACES_LIST                              \
 
80
        BUS_GENERIC_INTERFACES_LIST                  \
 
81
        "org.freedesktop.login1.Session\0"
 
82
 
 
83
static int bus_session_append_seat(DBusMessageIter *i, const char *property, void *data) {
 
84
        DBusMessageIter sub;
 
85
        Session *s = data;
 
86
        const char *id, *path;
 
87
        char *p = NULL;
 
88
 
 
89
        assert(i);
 
90
        assert(property);
 
91
        assert(s);
 
92
 
 
93
        if (!dbus_message_iter_open_container(i, DBUS_TYPE_STRUCT, NULL, &sub))
 
94
                return -ENOMEM;
 
95
 
 
96
        if (s->seat) {
 
97
                id = s->seat->id;
 
98
                path = p = seat_bus_path(s->seat);
 
99
 
 
100
                if (!p)
 
101
                        return -ENOMEM;
 
102
        } else {
 
103
                id = "";
 
104
                path = "/";
 
105
        }
 
106
 
 
107
        if (!dbus_message_iter_append_basic(&sub, DBUS_TYPE_STRING, &id) ||
 
108
            !dbus_message_iter_append_basic(&sub, DBUS_TYPE_OBJECT_PATH, &path)) {
 
109
                free(p);
 
110
                return -ENOMEM;
 
111
        }
 
112
 
 
113
        free(p);
 
114
 
 
115
        if (!dbus_message_iter_close_container(i, &sub))
 
116
                return -ENOMEM;
 
117
 
 
118
        return 0;
 
119
}
 
120
 
 
121
static int bus_session_append_user(DBusMessageIter *i, const char *property, void *data) {
 
122
        DBusMessageIter sub;
 
123
        User *u = data;
 
124
        char *p = NULL;
 
125
 
 
126
        assert(i);
 
127
        assert(property);
 
128
        assert(u);
 
129
 
 
130
        if (!dbus_message_iter_open_container(i, DBUS_TYPE_STRUCT, NULL, &sub))
 
131
                return -ENOMEM;
 
132
 
 
133
        p = user_bus_path(u);
 
134
        if (!p)
 
135
                return -ENOMEM;
 
136
 
 
137
        if (!dbus_message_iter_append_basic(&sub, DBUS_TYPE_UINT32, &u->uid) ||
 
138
            !dbus_message_iter_append_basic(&sub, DBUS_TYPE_OBJECT_PATH, &p)) {
 
139
                free(p);
 
140
                return -ENOMEM;
 
141
        }
 
142
 
 
143
        free(p);
 
144
 
 
145
        if (!dbus_message_iter_close_container(i, &sub))
 
146
                return -ENOMEM;
 
147
 
 
148
        return 0;
 
149
}
 
150
 
 
151
static int bus_session_append_active(DBusMessageIter *i, const char *property, void *data) {
 
152
        Session *s = data;
 
153
        dbus_bool_t b;
 
154
 
 
155
        assert(i);
 
156
        assert(property);
 
157
        assert(s);
 
158
 
 
159
        b = session_is_active(s);
 
160
        if (!dbus_message_iter_append_basic(i, DBUS_TYPE_BOOLEAN, &b))
 
161
                return -ENOMEM;
 
162
 
 
163
        return 0;
 
164
}
 
165
 
 
166
static int bus_session_append_idle_hint(DBusMessageIter *i, const char *property, void *data) {
 
167
        Session *s = data;
 
168
        int b;
 
169
 
 
170
        assert(i);
 
171
        assert(property);
 
172
        assert(s);
 
173
 
 
174
        b = session_get_idle_hint(s, NULL) > 0;
 
175
        if (!dbus_message_iter_append_basic(i, DBUS_TYPE_BOOLEAN, &b))
 
176
                return -ENOMEM;
 
177
 
 
178
        return 0;
 
179
}
 
180
 
 
181
static int bus_session_append_idle_hint_since(DBusMessageIter *i, const char *property, void *data) {
 
182
        Session *s = data;
 
183
        dual_timestamp t;
 
184
        uint64_t u;
 
185
 
 
186
        assert(i);
 
187
        assert(property);
 
188
        assert(s);
 
189
 
 
190
        session_get_idle_hint(s, &t);
 
191
        u = streq(property, "IdleSinceHint") ? t.realtime : t.monotonic;
 
192
 
 
193
        if (!dbus_message_iter_append_basic(i, DBUS_TYPE_UINT64, &u))
 
194
                return -ENOMEM;
 
195
 
 
196
        return 0;
 
197
}
 
198
 
 
199
static DEFINE_BUS_PROPERTY_APPEND_ENUM(bus_session_append_type, session_type, SessionType);
 
200
static DEFINE_BUS_PROPERTY_APPEND_ENUM(bus_session_append_class, session_class, SessionClass);
 
201
 
 
202
static int get_session_for_path(Manager *m, const char *path, Session **_s) {
 
203
        Session *s;
 
204
        char *id;
 
205
 
 
206
        assert(m);
 
207
        assert(path);
 
208
        assert(_s);
 
209
 
 
210
        if (!startswith(path, "/org/freedesktop/login1/session/"))
 
211
                return -EINVAL;
 
212
 
 
213
        id = bus_path_unescape(path + 32);
 
214
        if (!id)
 
215
                return -ENOMEM;
 
216
 
 
217
        s = hashmap_get(m->sessions, id);
 
218
        free(id);
 
219
 
 
220
        if (!s)
 
221
                return -ENOENT;
 
222
 
 
223
        *_s = s;
 
224
        return 0;
 
225
}
 
226
 
 
227
static const BusProperty bus_login_session_properties[] = {
 
228
        { "Id",                     bus_property_append_string,         "s", offsetof(Session, id),                 true },
 
229
        { "Timestamp",              bus_property_append_usec,           "t", offsetof(Session, timestamp.realtime)  },
 
230
        { "TimestampMonotonic",     bus_property_append_usec,           "t", offsetof(Session, timestamp.monotonic) },
 
231
        { "ControlGroupPath",       bus_property_append_string,         "s", offsetof(Session, cgroup_path),        true },
 
232
        { "VTNr",                   bus_property_append_uint32,         "u", offsetof(Session, vtnr)                },
 
233
        { "Seat",                   bus_session_append_seat,         "(so)", 0 },
 
234
        { "TTY",                    bus_property_append_string,         "s", offsetof(Session, tty),                true },
 
235
        { "Display",                bus_property_append_string,         "s", offsetof(Session, display),            true },
 
236
        { "Remote",                 bus_property_append_bool,           "b", offsetof(Session, remote)              },
 
237
        { "RemoteUser",             bus_property_append_string,         "s", offsetof(Session, remote_user),        true },
 
238
        { "RemoteHost",             bus_property_append_string,         "s", offsetof(Session, remote_host),        true },
 
239
        { "Service",                bus_property_append_string,         "s", offsetof(Session, service),            true },
 
240
        { "Leader",                 bus_property_append_pid,            "u", offsetof(Session, leader)              },
 
241
        { "Audit",                  bus_property_append_uint32,         "u", offsetof(Session, audit_id)            },
 
242
        { "Type",                   bus_session_append_type,            "s", offsetof(Session, type)                },
 
243
        { "Class",                  bus_session_append_class,           "s", offsetof(Session, class)               },
 
244
        { "Active",                 bus_session_append_active,          "b", 0 },
 
245
        { "Controllers",            bus_property_append_strv,          "as", offsetof(Session, controllers),        true },
 
246
        { "ResetControllers",       bus_property_append_strv,          "as", offsetof(Session, reset_controllers),  true },
 
247
        { "KillProcesses",          bus_property_append_bool,           "b", offsetof(Session, kill_processes)      },
 
248
        { "IdleHint",               bus_session_append_idle_hint,       "b", 0 },
 
249
        { "IdleSinceHint",          bus_session_append_idle_hint_since, "t", 0 },
 
250
        { "IdleSinceHintMonotonic", bus_session_append_idle_hint_since, "t", 0 },
 
251
        { NULL, }
 
252
};
 
253
 
 
254
static const BusProperty bus_login_session_user_properties[] = {
 
255
        { "User",                   bus_session_append_user,         "(uo)", 0 },
 
256
        { "Name",                   bus_property_append_string,         "s", offsetof(User, name),                  true },
 
257
        { NULL, }
 
258
};
 
259
 
 
260
static DBusHandlerResult session_message_dispatch(
 
261
                Session *s,
 
262
                DBusConnection *connection,
 
263
                DBusMessage *message) {
 
264
 
 
265
        DBusError error;
 
266
        DBusMessage *reply = NULL;
 
267
        int r;
 
268
 
 
269
        assert(s);
 
270
        assert(connection);
 
271
        assert(message);
 
272
 
 
273
        dbus_error_init(&error);
 
274
 
 
275
        if (dbus_message_is_method_call(message, "org.freedesktop.login1.Session", "Terminate")) {
 
276
 
 
277
                r = session_stop(s);
 
278
                if (r < 0)
 
279
                        return bus_send_error_reply(connection, message, NULL, r);
 
280
 
 
281
                reply = dbus_message_new_method_return(message);
 
282
                if (!reply)
 
283
                        goto oom;
 
284
 
 
285
        } else if (dbus_message_is_method_call(message, "org.freedesktop.login1.Session", "Activate")) {
 
286
 
 
287
                r = session_activate(s);
 
288
                if (r < 0)
 
289
                        return bus_send_error_reply(connection, message, NULL, r);
 
290
 
 
291
                reply = dbus_message_new_method_return(message);
 
292
                if (!reply)
 
293
                        goto oom;
 
294
 
 
295
        } else if (dbus_message_is_method_call(message, "org.freedesktop.login1.Session", "Lock") ||
 
296
                   dbus_message_is_method_call(message, "org.freedesktop.login1.Session", "Unlock")) {
 
297
 
 
298
                if (session_send_lock(s, streq(dbus_message_get_member(message), "Lock")) < 0)
 
299
                        goto oom;
 
300
 
 
301
                reply = dbus_message_new_method_return(message);
 
302
                if (!reply)
 
303
                        goto oom;
 
304
 
 
305
        } else if (dbus_message_is_method_call(message, "org.freedesktop.login1.Session", "SetIdleHint")) {
 
306
                dbus_bool_t b;
 
307
                unsigned long ul;
 
308
 
 
309
                if (!dbus_message_get_args(
 
310
                                    message,
 
311
                                    &error,
 
312
                                    DBUS_TYPE_BOOLEAN, &b,
 
313
                                    DBUS_TYPE_INVALID))
 
314
                        return bus_send_error_reply(connection, message, &error, -EINVAL);
 
315
 
 
316
                ul = dbus_bus_get_unix_user(connection, dbus_message_get_sender(message), &error);
 
317
                if (ul == (unsigned long) -1)
 
318
                        return bus_send_error_reply(connection, message, &error, -EIO);
 
319
 
 
320
                if (ul != 0 && ul != s->user->uid)
 
321
                        return bus_send_error_reply(connection, message, NULL, -EPERM);
 
322
 
 
323
                session_set_idle_hint(s, b);
 
324
 
 
325
                reply = dbus_message_new_method_return(message);
 
326
                if (!reply)
 
327
                        goto oom;
 
328
 
 
329
        } else if (dbus_message_is_method_call(message, "org.freedesktop.login1.Session", "Kill")) {
 
330
                const char *swho;
 
331
                int32_t signo;
 
332
                KillWho who;
 
333
 
 
334
                if (!dbus_message_get_args(
 
335
                                    message,
 
336
                                    &error,
 
337
                                    DBUS_TYPE_STRING, &swho,
 
338
                                    DBUS_TYPE_INT32, &signo,
 
339
                                    DBUS_TYPE_INVALID))
 
340
                        return bus_send_error_reply(connection, message, &error, -EINVAL);
 
341
 
 
342
                if (isempty(swho))
 
343
                        who = KILL_ALL;
 
344
                else {
 
345
                        who = kill_who_from_string(swho);
 
346
                        if (who < 0)
 
347
                                return bus_send_error_reply(connection, message, &error, -EINVAL);
 
348
                }
 
349
 
 
350
                if (signo <= 0 || signo >= _NSIG)
 
351
                        return bus_send_error_reply(connection, message, &error, -EINVAL);
 
352
 
 
353
                r = session_kill(s, who, signo);
 
354
                if (r < 0)
 
355
                        return bus_send_error_reply(connection, message, NULL, r);
 
356
 
 
357
                reply = dbus_message_new_method_return(message);
 
358
                if (!reply)
 
359
                        goto oom;
 
360
 
 
361
        } else {
 
362
                const BusBoundProperties bps[] = {
 
363
                        { "org.freedesktop.login1.Session", bus_login_session_properties,      s       },
 
364
                        { "org.freedesktop.login1.Session", bus_login_session_user_properties, s->user },
 
365
                        { NULL, }
 
366
                };
 
367
                return bus_default_message_handler(connection, message, INTROSPECTION, INTERFACES_LIST, bps);
 
368
        }
 
369
 
 
370
        if (reply) {
 
371
                if (!dbus_connection_send(connection, reply, NULL))
 
372
                        goto oom;
 
373
 
 
374
                dbus_message_unref(reply);
 
375
        }
 
376
 
 
377
        return DBUS_HANDLER_RESULT_HANDLED;
 
378
 
 
379
oom:
 
380
        if (reply)
 
381
                dbus_message_unref(reply);
 
382
 
 
383
        dbus_error_free(&error);
 
384
 
 
385
        return DBUS_HANDLER_RESULT_NEED_MEMORY;
 
386
}
 
387
 
 
388
static DBusHandlerResult session_message_handler(
 
389
                DBusConnection *connection,
 
390
                DBusMessage *message,
 
391
                void *userdata) {
 
392
 
 
393
        Manager *m = userdata;
 
394
        Session *s;
 
395
        int r;
 
396
 
 
397
        r = get_session_for_path(m, dbus_message_get_path(message), &s);
 
398
        if (r < 0) {
 
399
 
 
400
                if (r == -ENOMEM)
 
401
                        return DBUS_HANDLER_RESULT_NEED_MEMORY;
 
402
 
 
403
                if (r == -ENOENT) {
 
404
                        DBusError e;
 
405
 
 
406
                        dbus_error_init(&e);
 
407
                        dbus_set_error_const(&e, DBUS_ERROR_UNKNOWN_OBJECT, "Unknown session");
 
408
                        return bus_send_error_reply(connection, message, &e, r);
 
409
                }
 
410
 
 
411
                return bus_send_error_reply(connection, message, NULL, r);
 
412
        }
 
413
 
 
414
        return session_message_dispatch(s, connection, message);
 
415
}
 
416
 
 
417
const DBusObjectPathVTable bus_session_vtable = {
 
418
        .message_function = session_message_handler
 
419
};
 
420
 
 
421
char *session_bus_path(Session *s) {
 
422
        char *t, *r;
 
423
 
 
424
        assert(s);
 
425
 
 
426
        t = bus_path_escape(s->id);
 
427
        if (!t)
 
428
                return NULL;
 
429
 
 
430
        r = strappend("/org/freedesktop/login1/session/", t);
 
431
        free(t);
 
432
 
 
433
        return r;
 
434
}
 
435
 
 
436
int session_send_signal(Session *s, bool new_session) {
 
437
        DBusMessage *m;
 
438
        int r = -ENOMEM;
 
439
        char *p = NULL;
 
440
 
 
441
        assert(s);
 
442
 
 
443
        m = dbus_message_new_signal("/org/freedesktop/login1",
 
444
                                    "org.freedesktop.login1.Manager",
 
445
                                    new_session ? "SessionNew" : "SessionRemoved");
 
446
 
 
447
        if (!m)
 
448
                return -ENOMEM;
 
449
 
 
450
        p = session_bus_path(s);
 
451
        if (!p)
 
452
                goto finish;
 
453
 
 
454
        if (!dbus_message_append_args(
 
455
                            m,
 
456
                            DBUS_TYPE_STRING, &s->id,
 
457
                            DBUS_TYPE_OBJECT_PATH, &p,
 
458
                            DBUS_TYPE_INVALID))
 
459
                goto finish;
 
460
 
 
461
        if (!dbus_connection_send(s->manager->bus, m, NULL))
 
462
                goto finish;
 
463
 
 
464
        r = 0;
 
465
 
 
466
finish:
 
467
        dbus_message_unref(m);
 
468
        free(p);
 
469
 
 
470
        return r;
 
471
}
 
472
 
 
473
int session_send_changed(Session *s, const char *properties) {
 
474
        DBusMessage *m;
 
475
        int r = -ENOMEM;
 
476
        char *p = NULL;
 
477
 
 
478
        assert(s);
 
479
 
 
480
        if (!s->started)
 
481
                return 0;
 
482
 
 
483
        p = session_bus_path(s);
 
484
        if (!p)
 
485
                return -ENOMEM;
 
486
 
 
487
        m = bus_properties_changed_new(p, "org.freedesktop.login1.Session", properties);
 
488
        if (!m)
 
489
                goto finish;
 
490
 
 
491
        if (!dbus_connection_send(s->manager->bus, m, NULL))
 
492
                goto finish;
 
493
 
 
494
        r = 0;
 
495
 
 
496
finish:
 
497
        if (m)
 
498
                dbus_message_unref(m);
 
499
        free(p);
 
500
 
 
501
        return r;
 
502
}
 
503
 
 
504
int session_send_lock(Session *s, bool lock) {
 
505
        DBusMessage *m;
 
506
        bool b;
 
507
        char *p;
 
508
 
 
509
        assert(s);
 
510
 
 
511
        p = session_bus_path(s);
 
512
        if (!p)
 
513
                return -ENOMEM;
 
514
 
 
515
        m = dbus_message_new_signal(p, "org.freedesktop.login1.Session", lock ? "Lock" : "Unlock");
 
516
        free(p);
 
517
 
 
518
        if (!m)
 
519
                return -ENOMEM;
 
520
 
 
521
        b = dbus_connection_send(s->manager->bus, m, NULL);
 
522
        dbus_message_unref(m);
 
523
 
 
524
        if (!b)
 
525
                return -ENOMEM;
 
526
 
 
527
        return 0;
 
528
}