ipc/msg.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * linux/ipc/msg.c
   4  * Copyright (C) 1992 Krishna Balasubramanian
   5  *
   6  * Removed all the remaining kerneld mess
   7  * Catch the -EFAULT stuff properly
   8  * Use GFP_KERNEL for messages as in 1.2
   9  * Fixed up the unchecked user space derefs
  10  * Copyright (C) 1998 Alan Cox & Andi Kleen
  11  *
  12  * /proc/sysvipc/msg support (c) 1999 Dragos Acostachioaie <dragos@iname.com>
  13  *
  14  * mostly rewritten, threaded and wake-one semantics added
  15  * MSGMAX limit removed, sysctl's added
  16  * (c) 1999 Manfred Spraul <manfred@colorfullife.com>
  17  *
  18  * support for audit of ipc object properties and permission changes
  19  * Dustin Kirkland <dustin.kirkland@us.ibm.com>
  20  *
  21  * namespaces support
  22  * OpenVZ, SWsoft Inc.
  23  * Pavel Emelianov <xemul@openvz.org>
  24  */
  25
  26 #include <linux/capability.h>
  27 #include <linux/msg.h>
  28 #include <linux/spinlock.h>
  29 #include <linux/init.h>
  30 #include <linux/mm.h>
  31 #include <linux/proc_fs.h>
  32 #include <linux/list.h>
  33 #include <linux/security.h>
  34 #include <linux/sched/wake_q.h>
  35 #include <linux/syscalls.h>
  36 #include <linux/audit.h>
  37 #include <linux/seq_file.h>
  38 #include <linux/rwsem.h>
  39 #include <linux/nsproxy.h>
  40 #include <linux/ipc_namespace.h>
  41 #include <linux/rhashtable.h>
  42
  43 #include <asm/current.h>
  44 #include <linux/uaccess.h>
  45 #include "util.h"
  46
  47 /* one msq_queue structure for each present queue on the system */
  48 struct msg_queue {
  49         struct kern_ipc_perm q_perm;
  50         time64_t q_stime;               /* last msgsnd time */
  51         time64_t q_rtime;               /* last msgrcv time */
  52         time64_t q_ctime;               /* last change time */
  53         unsigned long q_cbytes;         /* current number of bytes on queue */
  54         unsigned long q_qnum;           /* number of messages in queue */
  55         unsigned long q_qbytes;         /* max number of bytes on queue */
  56         struct pid *q_lspid;            /* pid of last msgsnd */
  57         struct pid *q_lrpid;            /* last receive pid */
  58
  59         struct list_head q_messages;
  60         struct list_head q_receivers;
  61         struct list_head q_senders;
  62 } __randomize_layout;
  63
  64 /* one msg_receiver structure for each sleeping receiver */
  65 struct msg_receiver {
  66         struct list_head        r_list;
  67         struct task_struct      *r_tsk;
  68
  69         int                     r_mode;
  70         long                    r_msgtype;
  71         long                    r_maxsize;
  72
  73         struct msg_msg          *r_msg;
  74 };
  75
  76 /* one msg_sender for each sleeping sender */
  77 struct msg_sender {
  78         struct list_head        list;
  79         struct task_struct      *tsk;
  80         size_t                  msgsz;
  81 };
  82
  83 #define SEARCH_ANY              1
  84 #define SEARCH_EQUAL            2
  85 #define SEARCH_NOTEQUAL         3
  86 #define SEARCH_LESSEQUAL        4
  87 #define SEARCH_NUMBER           5
  88
  89 #define msg_ids(ns)     ((ns)->ids[IPC_MSG_IDS])
  90
  91 static inline struct msg_queue *msq_obtain_object(struct ipc_namespace *ns, int id)
  92 {
  93         struct kern_ipc_perm *ipcp = ipc_obtain_object_idr(&msg_ids(ns), id);
  94
  95         if (IS_ERR(ipcp))
  96                 return ERR_CAST(ipcp);
  97
  98         return container_of(ipcp, struct msg_queue, q_perm);
  99 }
 100
 101 static inline struct msg_queue *msq_obtain_object_check(struct ipc_namespace *ns,
 102                                                         int id)
 103 {
 104         struct kern_ipc_perm *ipcp = ipc_obtain_object_check(&msg_ids(ns), id);
 105
 106         if (IS_ERR(ipcp))
 107                 return ERR_CAST(ipcp);
 108
 109         return container_of(ipcp, struct msg_queue, q_perm);
 110 }
 111
 112 static inline void msg_rmid(struct ipc_namespace *ns, struct msg_queue *s)
 113 {
 114         ipc_rmid(&msg_ids(ns), &s->q_perm);
 115 }
 116
 117 static void msg_rcu_free(struct rcu_head *head)
 118 {
 119         struct kern_ipc_perm *p = container_of(head, struct kern_ipc_perm, rcu);
 120         struct msg_queue *msq = container_of(p, struct msg_queue, q_perm);
 121
 122         security_msg_queue_free(&msq->q_perm);
 123         kvfree(msq);
 124 }
 125
 126 /**
 127  * newque - Create a new msg queue
 128  * @ns: namespace
 129  * @params: ptr to the structure that contains the key and msgflg
 130  *
 131  * Called with msg_ids.rwsem held (writer)
 132  */
 133 static int newque(struct ipc_namespace *ns, struct ipc_params *params)
 134 {
 135         struct msg_queue *msq;
 136         int retval;
 137         key_t key = params->key;
 138         int msgflg = params->flg;
 139
 140         msq = kvmalloc(sizeof(*msq), GFP_KERNEL);
 141         if (unlikely(!msq))
 142                 return -ENOMEM;
 143
 144         msq->q_perm.mode = msgflg & S_IRWXUGO;
 145         msq->q_perm.key = key;
 146
 147         msq->q_perm.security = NULL;
 148         retval = security_msg_queue_alloc(&msq->q_perm);
 149         if (retval) {
 150                 kvfree(msq);
 151                 return retval;
 152         }
 153
 154         msq->q_stime = msq->q_rtime = 0;
 155         msq->q_ctime = ktime_get_real_seconds();
 156         msq->q_cbytes = msq->q_qnum = 0;
 157         msq->q_qbytes = ns->msg_ctlmnb;
 158         msq->q_lspid = msq->q_lrpid = NULL;
 159         INIT_LIST_HEAD(&msq->q_messages);
 160         INIT_LIST_HEAD(&msq->q_receivers);
 161         INIT_LIST_HEAD(&msq->q_senders);
 162
 163         /* ipc_addid() locks msq upon success. */
 164         retval = ipc_addid(&msg_ids(ns), &msq->q_perm, ns->msg_ctlmni);
 165         if (retval < 0) {
 166                 ipc_rcu_putref(&msq->q_perm, msg_rcu_free);
 167                 return retval;
 168         }
 169
 170         ipc_unlock_object(&msq->q_perm);
 171         rcu_read_unlock();
 172
 173         return msq->q_perm.id;
 174 }
 175
 176 static inline bool msg_fits_inqueue(struct msg_queue *msq, size_t msgsz)
 177 {
 178         return msgsz + msq->q_cbytes <= msq->q_qbytes &&
 179                 1 + msq->q_qnum <= msq->q_qbytes;
 180 }
 181
 182 static inline void ss_add(struct msg_queue *msq,
 183                           struct msg_sender *mss, size_t msgsz)
 184 {
 185         mss->tsk = current;
 186         mss->msgsz = msgsz;
 187         __set_current_state(TASK_INTERRUPTIBLE);
 188         list_add_tail(&mss->list, &msq->q_senders);
 189 }
 190
 191 static inline void ss_del(struct msg_sender *mss)
 192 {
 193         if (mss->list.next)
 194                 list_del(&mss->list);
 195 }
 196
 197 static void ss_wakeup(struct msg_queue *msq,
 198                       struct wake_q_head *wake_q, bool kill)
 199 {
 200         struct msg_sender *mss, *t;
 201         struct task_struct *stop_tsk = NULL;
 202         struct list_head *h = &msq->q_senders;
 203
 204         list_for_each_entry_safe(mss, t, h, list) {
 205                 if (kill)
 206                         mss->list.next = NULL;
 207
 208                 /*
 209                  * Stop at the first task we don't wakeup,
 210                  * we've already iterated the original
 211                  * sender queue.
 212                  */
 213                 else if (stop_tsk == mss->tsk)
 214                         break;
 215                 /*
 216                  * We are not in an EIDRM scenario here, therefore
 217                  * verify that we really need to wakeup the task.
 218                  * To maintain current semantics and wakeup order,
 219                  * move the sender to the tail on behalf of the
 220                  * blocked task.
 221                  */
 222                 else if (!msg_fits_inqueue(msq, mss->msgsz)) {
 223                         if (!stop_tsk)
 224                                 stop_tsk = mss->tsk;
 225
 226                         list_move_tail(&mss->list, &msq->q_senders);
 227                         continue;
 228                 }
 229
 230                 wake_q_add(wake_q, mss->tsk);
 231         }
 232 }
 233
 234 static void expunge_all(struct msg_queue *msq, int res,
 235                         struct wake_q_head *wake_q)
 236 {
 237         struct msg_receiver *msr, *t;
 238
 239         list_for_each_entry_safe(msr, t, &msq->q_receivers, r_list) {
 240                 wake_q_add(wake_q, msr->r_tsk);
 241                 WRITE_ONCE(msr->r_msg, ERR_PTR(res));
 242         }
 243 }
 244
 245 /*
 246  * freeque() wakes up waiters on the sender and receiver waiting queue,
 247  * removes the message queue from message queue ID IDR, and cleans up all the
 248  * messages associated with this queue.
 249  *
 250  * msg_ids.rwsem (writer) and the spinlock for this message queue are held
 251  * before freeque() is called. msg_ids.rwsem remains locked on exit.
 252  */
 253 static void freeque(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp)
 254 {
 255         struct msg_msg *msg, *t;
 256         struct msg_queue *msq = container_of(ipcp, struct msg_queue, q_perm);
 257         DEFINE_WAKE_Q(wake_q);
 258
 259         expunge_all(msq, -EIDRM, &wake_q);
 260         ss_wakeup(msq, &wake_q, true);
 261         msg_rmid(ns, msq);
 262         ipc_unlock_object(&msq->q_perm);
 263         wake_up_q(&wake_q);
 264         rcu_read_unlock();
 265
 266         list_for_each_entry_safe(msg, t, &msq->q_messages, m_list) {
 267                 atomic_dec(&ns->msg_hdrs);
 268                 free_msg(msg);
 269         }
 270         atomic_sub(msq->q_cbytes, &ns->msg_bytes);
 271         ipc_update_pid(&msq->q_lspid, NULL);
 272         ipc_update_pid(&msq->q_lrpid, NULL);
 273         ipc_rcu_putref(&msq->q_perm, msg_rcu_free);
 274 }
 275
 276 long ksys_msgget(key_t key, int msgflg)
 277 {
 278         struct ipc_namespace *ns;
 279         static const struct ipc_ops msg_ops = {
 280                 .getnew = newque,
 281                 .associate = security_msg_queue_associate,
 282         };
 283         struct ipc_params msg_params;
 284
 285         ns = current->nsproxy->ipc_ns;
 286
 287         msg_params.key = key;
 288         msg_params.flg = msgflg;
 289
 290         return ipcget(ns, &msg_ids(ns), &msg_ops, &msg_params);
 291 }
 292
 293 SYSCALL_DEFINE2(msgget, key_t, key, int, msgflg)
 294 {
 295         return ksys_msgget(key, msgflg);
 296 }
 297
 298 static inline unsigned long
 299 copy_msqid_to_user(void __user *buf, struct msqid64_ds *in, int version)
 300 {
 301         switch (version) {
 302         case IPC_64:
 303                 return copy_to_user(buf, in, sizeof(*in));
 304         case IPC_OLD:
 305         {
 306                 struct msqid_ds out;
 307
 308                 memset(&out, 0, sizeof(out));
 309
 310                 ipc64_perm_to_ipc_perm(&in->msg_perm, &out.msg_perm);
 311
 312                 out.msg_stime           = in->msg_stime;
 313                 out.msg_rtime           = in->msg_rtime;
 314                 out.msg_ctime           = in->msg_ctime;
 315
 316                 if (in->msg_cbytes > USHRT_MAX)
 317                         out.msg_cbytes  = USHRT_MAX;
 318                 else
 319                         out.msg_cbytes  = in->msg_cbytes;
 320                 out.msg_lcbytes         = in->msg_cbytes;
 321
 322                 if (in->msg_qnum > USHRT_MAX)
 323                         out.msg_qnum    = USHRT_MAX;
 324                 else
 325                         out.msg_qnum    = in->msg_qnum;
 326
 327                 if (in->msg_qbytes > USHRT_MAX)
 328                         out.msg_qbytes  = USHRT_MAX;
 329                 else
 330                         out.msg_qbytes  = in->msg_qbytes;
 331                 out.msg_lqbytes         = in->msg_qbytes;
 332
 333                 out.msg_lspid           = in->msg_lspid;
 334                 out.msg_lrpid           = in->msg_lrpid;
 335
 336                 return copy_to_user(buf, &out, sizeof(out));
 337         }
 338         default:
 339                 return -EINVAL;
 340         }
 341 }
 342
 343 static inline unsigned long
 344 copy_msqid_from_user(struct msqid64_ds *out, void __user *buf, int version)
 345 {
 346         switch (version) {
 347         case IPC_64:
 348                 if (copy_from_user(out, buf, sizeof(*out)))
 349                         return -EFAULT;
 350                 return 0;
 351         case IPC_OLD:
 352         {
 353                 struct msqid_ds tbuf_old;
 354
 355                 if (copy_from_user(&tbuf_old, buf, sizeof(tbuf_old)))
 356                         return -EFAULT;
 357
 358                 out->msg_perm.uid       = tbuf_old.msg_perm.uid;
 359                 out->msg_perm.gid       = tbuf_old.msg_perm.gid;
 360                 out->msg_perm.mode      = tbuf_old.msg_perm.mode;
 361
 362                 if (tbuf_old.msg_qbytes == 0)
 363                         out->msg_qbytes = tbuf_old.msg_lqbytes;
 364                 else
 365                         out->msg_qbytes = tbuf_old.msg_qbytes;
 366
 367                 return 0;
 368         }
 369         default:
 370                 return -EINVAL;
 371         }
 372 }
 373
 374 /*
 375  * This function handles some msgctl commands which require the rwsem
 376  * to be held in write mode.
 377  * NOTE: no locks must be held, the rwsem is taken inside this function.
 378  */
 379 static int msgctl_down(struct ipc_namespace *ns, int msqid, int cmd,
 380                         struct msqid64_ds *msqid64)
 381 {
 382         struct kern_ipc_perm *ipcp;
 383         struct msg_queue *msq;
 384         int err;
 385
 386         down_write(&msg_ids(ns).rwsem);
 387         rcu_read_lock();
 388
 389         ipcp = ipcctl_obtain_check(ns, &msg_ids(ns), msqid, cmd,
 390                                       &msqid64->msg_perm, msqid64->msg_qbytes);
 391         if (IS_ERR(ipcp)) {
 392                 err = PTR_ERR(ipcp);
 393                 goto out_unlock1;
 394         }
 395
 396         msq = container_of(ipcp, struct msg_queue, q_perm);
 397
 398         err = security_msg_queue_msgctl(&msq->q_perm, cmd);
 399         if (err)
 400                 goto out_unlock1;
 401
 402         switch (cmd) {
 403         case IPC_RMID:
 404                 ipc_lock_object(&msq->q_perm);
 405                 /* freeque unlocks the ipc object and rcu */
 406                 freeque(ns, ipcp);
 407                 goto out_up;
 408         case IPC_SET:
 409         {
 410                 DEFINE_WAKE_Q(wake_q);
 411
 412                 if (msqid64->msg_qbytes > ns->msg_ctlmnb &&
 413                     !capable(CAP_SYS_RESOURCE)) {
 414                         err = -EPERM;
 415                         goto out_unlock1;
 416                 }
 417
 418                 ipc_lock_object(&msq->q_perm);
 419                 err = ipc_update_perm(&msqid64->msg_perm, ipcp);
 420                 if (err)
 421                         goto out_unlock0;
 422
 423                 msq->q_qbytes = msqid64->msg_qbytes;
 424
 425                 msq->q_ctime = ktime_get_real_seconds();
 426                 /*
 427                  * Sleeping receivers might be excluded by
 428                  * stricter permissions.
 429                  */
 430                 expunge_all(msq, -EAGAIN, &wake_q);
 431                 /*
 432                  * Sleeping senders might be able to send
 433                  * due to a larger queue size.
 434                  */
 435                 ss_wakeup(msq, &wake_q, false);
 436                 ipc_unlock_object(&msq->q_perm);
 437                 wake_up_q(&wake_q);
 438
 439                 goto out_unlock1;
 440         }
 441         default:
 442                 err = -EINVAL;
 443                 goto out_unlock1;
 444         }
 445
 446 out_unlock0:
 447         ipc_unlock_object(&msq->q_perm);
 448 out_unlock1:
 449         rcu_read_unlock();
 450 out_up:
 451         up_write(&msg_ids(ns).rwsem);
 452         return err;
 453 }
 454
 455 static int msgctl_info(struct ipc_namespace *ns, int msqid,
 456                          int cmd, struct msginfo *msginfo)
 457 {
 458         int err;
 459         int max_idx;
 460
 461         /*
 462          * We must not return kernel stack data.
 463          * due to padding, it's not enough
 464          * to set all member fields.
 465          */
 466         err = security_msg_queue_msgctl(NULL, cmd);
 467         if (err)
 468                 return err;
 469
 470         memset(msginfo, 0, sizeof(*msginfo));
 471         msginfo->msgmni = ns->msg_ctlmni;
 472         msginfo->msgmax = ns->msg_ctlmax;
 473         msginfo->msgmnb = ns->msg_ctlmnb;
 474         msginfo->msgssz = MSGSSZ;
 475         msginfo->msgseg = MSGSEG;
 476         down_read(&msg_ids(ns).rwsem);
 477         if (cmd == MSG_INFO) {
 478                 msginfo->msgpool = msg_ids(ns).in_use;
 479                 msginfo->msgmap = atomic_read(&ns->msg_hdrs);
 480                 msginfo->msgtql = atomic_read(&ns->msg_bytes);
 481         } else {
 482                 msginfo->msgmap = MSGMAP;
 483                 msginfo->msgpool = MSGPOOL;
 484                 msginfo->msgtql = MSGTQL;
 485         }
 486         max_idx = ipc_get_maxidx(&msg_ids(ns));
 487         up_read(&msg_ids(ns).rwsem);
 488         return (max_idx < 0) ? 0 : max_idx;
 489 }
 490
 491 static int msgctl_stat(struct ipc_namespace *ns, int msqid,
 492                          int cmd, struct msqid64_ds *p)
 493 {
 494         struct msg_queue *msq;
 495         int err;
 496
 497         memset(p, 0, sizeof(*p));
 498
 499         rcu_read_lock();
 500         if (cmd == MSG_STAT || cmd == MSG_STAT_ANY) {
 501                 msq = msq_obtain_object(ns, msqid);
 502                 if (IS_ERR(msq)) {
 503                         err = PTR_ERR(msq);
 504                         goto out_unlock;
 505                 }
 506         } else { /* IPC_STAT */
 507                 msq = msq_obtain_object_check(ns, msqid);
 508                 if (IS_ERR(msq)) {
 509                         err = PTR_ERR(msq);
 510                         goto out_unlock;
 511                 }
 512         }
 513
 514         /* see comment for SHM_STAT_ANY */
 515         if (cmd == MSG_STAT_ANY)
 516                 audit_ipc_obj(&msq->q_perm);
 517         else {
 518                 err = -EACCES;
 519                 if (ipcperms(ns, &msq->q_perm, S_IRUGO))
 520                         goto out_unlock;
 521         }
 522
 523         err = security_msg_queue_msgctl(&msq->q_perm, cmd);
 524         if (err)
 525                 goto out_unlock;
 526
 527         ipc_lock_object(&msq->q_perm);
 528
 529         if (!ipc_valid_object(&msq->q_perm)) {
 530                 ipc_unlock_object(&msq->q_perm);
 531                 err = -EIDRM;
 532                 goto out_unlock;
 533         }
 534
 535         kernel_to_ipc64_perm(&msq->q_perm, &p->msg_perm);
 536         p->msg_stime  = msq->q_stime;
 537         p->msg_rtime  = msq->q_rtime;
 538         p->msg_ctime  = msq->q_ctime;
 539 #ifndef CONFIG_64BIT
 540         p->msg_stime_high = msq->q_stime >> 32;
 541         p->msg_rtime_high = msq->q_rtime >> 32;
 542         p->msg_ctime_high = msq->q_ctime >> 32;
 543 #endif
 544         p->msg_cbytes = msq->q_cbytes;
 545         p->msg_qnum   = msq->q_qnum;
 546         p->msg_qbytes = msq->q_qbytes;
 547         p->msg_lspid  = pid_vnr(msq->q_lspid);
 548         p->msg_lrpid  = pid_vnr(msq->q_lrpid);
 549
 550         if (cmd == IPC_STAT) {
 551                 /*
 552                  * As defined in SUS:
 553                  * Return 0 on success
 554                  */
 555                 err = 0;
 556         } else {
 557                 /*
 558                  * MSG_STAT and MSG_STAT_ANY (both Linux specific)
 559                  * Return the full id, including the sequence number
 560                  */
 561                 err = msq->q_perm.id;
 562         }
 563
 564         ipc_unlock_object(&msq->q_perm);
 565 out_unlock:
 566         rcu_read_unlock();
 567         return err;
 568 }
 569
 570 static long ksys_msgctl(int msqid, int cmd, struct msqid_ds __user *buf, int version)
 571 {
 572         struct ipc_namespace *ns;
 573         struct msqid64_ds msqid64;
 574         int err;
 575
 576         if (msqid < 0 || cmd < 0)
 577                 return -EINVAL;
 578
 579         ns = current->nsproxy->ipc_ns;
 580
 581         switch (cmd) {
 582         case IPC_INFO:
 583         case MSG_INFO: {
 584                 struct msginfo msginfo;
 585                 err = msgctl_info(ns, msqid, cmd, &msginfo);
 586                 if (err < 0)
 587                         return err;
 588                 if (copy_to_user(buf, &msginfo, sizeof(struct msginfo)))
 589                         err = -EFAULT;
 590                 return err;
 591         }
 592         case MSG_STAT:  /* msqid is an index rather than a msg queue id */
 593         case MSG_STAT_ANY:
 594         case IPC_STAT:
 595                 err = msgctl_stat(ns, msqid, cmd, &msqid64);
 596                 if (err < 0)
 597                         return err;
 598                 if (copy_msqid_to_user(buf, &msqid64, version))
 599                         err = -EFAULT;
 600                 return err;
 601         case IPC_SET:
 602                 if (copy_msqid_from_user(&msqid64, buf, version))
 603                         return -EFAULT;
 604                 /* fallthru */
 605         case IPC_RMID:
 606                 return msgctl_down(ns, msqid, cmd, &msqid64);
 607         default:
 608                 return  -EINVAL;
 609         }
 610 }
 611
 612 SYSCALL_DEFINE3(msgctl, int, msqid, int, cmd, struct msqid_ds __user *, buf)
 613 {
 614         return ksys_msgctl(msqid, cmd, buf, IPC_64);
 615 }
 616
 617 #ifdef CONFIG_ARCH_WANT_IPC_PARSE_VERSION
 618 long ksys_old_msgctl(int msqid, int cmd, struct msqid_ds __user *buf)
 619 {
 620         int version = ipc_parse_version(&cmd);
 621
 622         return ksys_msgctl(msqid, cmd, buf, version);
 623 }
 624
 625 SYSCALL_DEFINE3(old_msgctl, int, msqid, int, cmd, struct msqid_ds __user *, buf)
 626 {
 627         return ksys_old_msgctl(msqid, cmd, buf);
 628 }
 629 #endif
 630
 631 #ifdef CONFIG_COMPAT
 632
 633 struct compat_msqid_ds {
 634         struct compat_ipc_perm msg_perm;
 635         compat_uptr_t msg_first;
 636         compat_uptr_t msg_last;
 637         old_time32_t msg_stime;
 638         old_time32_t msg_rtime;
 639         old_time32_t msg_ctime;
 640         compat_ulong_t msg_lcbytes;
 641         compat_ulong_t msg_lqbytes;
 642         unsigned short msg_cbytes;
 643         unsigned short msg_qnum;
 644         unsigned short msg_qbytes;
 645         compat_ipc_pid_t msg_lspid;
 646         compat_ipc_pid_t msg_lrpid;
 647 };
 648
 649 static int copy_compat_msqid_from_user(struct msqid64_ds *out, void __user *buf,
 650                                         int version)
 651 {
 652         memset(out, 0, sizeof(*out));
 653         if (version == IPC_64) {
 654                 struct compat_msqid64_ds __user *p = buf;
 655                 if (get_compat_ipc64_perm(&out->msg_perm, &p->msg_perm))
 656                         return -EFAULT;
 657                 if (get_user(out->msg_qbytes, &p->msg_qbytes))
 658                         return -EFAULT;
 659         } else {
 660                 struct compat_msqid_ds __user *p = buf;
 661                 if (get_compat_ipc_perm(&out->msg_perm, &p->msg_perm))
 662                         return -EFAULT;
 663                 if (get_user(out->msg_qbytes, &p->msg_qbytes))
 664                         return -EFAULT;
 665         }
 666         return 0;
 667 }
 668
 669 static int copy_compat_msqid_to_user(void __user *buf, struct msqid64_ds *in,
 670                                         int version)
 671 {
 672         if (version == IPC_64) {
 673                 struct compat_msqid64_ds v;
 674                 memset(&v, 0, sizeof(v));
 675                 to_compat_ipc64_perm(&v.msg_perm, &in->msg_perm);
 676                 v.msg_stime      = lower_32_bits(in->msg_stime);
 677                 v.msg_stime_high = upper_32_bits(in->msg_stime);
 678                 v.msg_rtime      = lower_32_bits(in->msg_rtime);
 679                 v.msg_rtime_high = upper_32_bits(in->msg_rtime);
 680                 v.msg_ctime      = lower_32_bits(in->msg_ctime);
 681                 v.msg_ctime_high = upper_32_bits(in->msg_ctime);
 682                 v.msg_cbytes = in->msg_cbytes;
 683                 v.msg_qnum = in->msg_qnum;
 684                 v.msg_qbytes = in->msg_qbytes;
 685                 v.msg_lspid = in->msg_lspid;
 686                 v.msg_lrpid = in->msg_lrpid;
 687                 return copy_to_user(buf, &v, sizeof(v));
 688         } else {
 689                 struct compat_msqid_ds v;
 690                 memset(&v, 0, sizeof(v));
 691                 to_compat_ipc_perm(&v.msg_perm, &in->msg_perm);
 692                 v.msg_stime = in->msg_stime;
 693                 v.msg_rtime = in->msg_rtime;
 694                 v.msg_ctime = in->msg_ctime;
 695                 v.msg_cbytes = in->msg_cbytes;
 696                 v.msg_qnum = in->msg_qnum;
 697                 v.msg_qbytes = in->msg_qbytes;
 698                 v.msg_lspid = in->msg_lspid;
 699                 v.msg_lrpid = in->msg_lrpid;
 700                 return copy_to_user(buf, &v, sizeof(v));
 701         }
 702 }
 703
 704 static long compat_ksys_msgctl(int msqid, int cmd, void __user *uptr, int version)
 705 {
 706         struct ipc_namespace *ns;
 707         int err;
 708         struct msqid64_ds msqid64;
 709
 710         ns = current->nsproxy->ipc_ns;
 711
 712         if (msqid < 0 || cmd < 0)
 713                 return -EINVAL;
 714
 715         switch (cmd & (~IPC_64)) {
 716         case IPC_INFO:
 717         case MSG_INFO: {
 718                 struct msginfo msginfo;
 719                 err = msgctl_info(ns, msqid, cmd, &msginfo);
 720                 if (err < 0)
 721                         return err;
 722                 if (copy_to_user(uptr, &msginfo, sizeof(struct msginfo)))
 723                         err = -EFAULT;
 724                 return err;
 725         }
 726         case IPC_STAT:
 727         case MSG_STAT:
 728         case MSG_STAT_ANY:
 729                 err = msgctl_stat(ns, msqid, cmd, &msqid64);
 730                 if (err < 0)
 731                         return err;
 732                 if (copy_compat_msqid_to_user(uptr, &msqid64, version))
 733                         err = -EFAULT;
 734                 return err;
 735         case IPC_SET:
 736                 if (copy_compat_msqid_from_user(&msqid64, uptr, version))
 737                         return -EFAULT;
 738                 /* fallthru */
 739         case IPC_RMID:
 740                 return msgctl_down(ns, msqid, cmd, &msqid64);
 741         default:
 742                 return -EINVAL;
 743         }
 744 }
 745
 746 COMPAT_SYSCALL_DEFINE3(msgctl, int, msqid, int, cmd, void __user *, uptr)
 747 {
 748         return compat_ksys_msgctl(msqid, cmd, uptr, IPC_64);
 749 }
 750
 751 #ifdef CONFIG_ARCH_WANT_COMPAT_IPC_PARSE_VERSION
 752 long compat_ksys_old_msgctl(int msqid, int cmd, void __user *uptr)
 753 {
 754         int version = compat_ipc_parse_version(&cmd);
 755
 756         return compat_ksys_msgctl(msqid, cmd, uptr, version);
 757 }
 758
 759 COMPAT_SYSCALL_DEFINE3(old_msgctl, int, msqid, int, cmd, void __user *, uptr)
 760 {
 761         return compat_ksys_old_msgctl(msqid, cmd, uptr);
 762 }
 763 #endif
 764 #endif
 765
 766 static int testmsg(struct msg_msg *msg, long type, int mode)
 767 {
 768         switch (mode) {
 769         case SEARCH_ANY:
 770         case SEARCH_NUMBER:
 771                 return 1;
 772         case SEARCH_LESSEQUAL:
 773                 if (msg->m_type <= type)
 774                         return 1;
 775                 break;
 776         case SEARCH_EQUAL:
 777                 if (msg->m_type == type)
 778                         return 1;
 779                 break;
 780         case SEARCH_NOTEQUAL:
 781                 if (msg->m_type != type)
 782                         return 1;
 783                 break;
 784         }
 785         return 0;
 786 }
 787
 788 static inline int pipelined_send(struct msg_queue *msq, struct msg_msg *msg,
 789                                  struct wake_q_head *wake_q)
 790 {
 791         struct msg_receiver *msr, *t;
 792
 793         list_for_each_entry_safe(msr, t, &msq->q_receivers, r_list) {
 794                 if (testmsg(msg, msr->r_msgtype, msr->r_mode) &&
 795                     !security_msg_queue_msgrcv(&msq->q_perm, msg, msr->r_tsk,
 796                                                msr->r_msgtype, msr->r_mode)) {
 797
 798                         list_del(&msr->r_list);
 799                         if (msr->r_maxsize < msg->m_ts) {
 800                                 wake_q_add(wake_q, msr->r_tsk);
 801                                 WRITE_ONCE(msr->r_msg, ERR_PTR(-E2BIG));
 802                         } else {
 803                                 ipc_update_pid(&msq->q_lrpid, task_pid(msr->r_tsk));
 804                                 msq->q_rtime = ktime_get_real_seconds();
 805
 806                                 wake_q_add(wake_q, msr->r_tsk);
 807                                 WRITE_ONCE(msr->r_msg, msg);
 808                                 return 1;
 809                         }
 810                 }
 811         }
 812
 813         return 0;
 814 }
 815
 816 static long do_msgsnd(int msqid, long mtype, void __user *mtext,
 817                 size_t msgsz, int msgflg)
 818 {
 819         struct msg_queue *msq;
 820         struct msg_msg *msg;
 821         int err;
 822         struct ipc_namespace *ns;
 823         DEFINE_WAKE_Q(wake_q);
 824
 825         ns = current->nsproxy->ipc_ns;
 826
 827         if (msgsz > ns->msg_ctlmax || (long) msgsz < 0 || msqid < 0)
 828                 return -EINVAL;
 829         if (mtype < 1)
 830                 return -EINVAL;
 831
 832         msg = load_msg(mtext, msgsz);
 833         if (IS_ERR(msg))
 834                 return PTR_ERR(msg);
 835
 836         msg->m_type = mtype;
 837         msg->m_ts = msgsz;
 838
 839         rcu_read_lock();
 840         msq = msq_obtain_object_check(ns, msqid);
 841         if (IS_ERR(msq)) {
 842                 err = PTR_ERR(msq);
 843                 goto out_unlock1;
 844         }
 845
 846         ipc_lock_object(&msq->q_perm);
 847
 848         for (;;) {
 849                 struct msg_sender s;
 850
 851                 err = -EACCES;
 852                 if (ipcperms(ns, &msq->q_perm, S_IWUGO))
 853                         goto out_unlock0;
 854
 855                 /* raced with RMID? */
 856                 if (!ipc_valid_object(&msq->q_perm)) {
 857                         err = -EIDRM;
 858                         goto out_unlock0;
 859                 }
 860
 861                 err = security_msg_queue_msgsnd(&msq->q_perm, msg, msgflg);
 862                 if (err)
 863                         goto out_unlock0;
 864
 865                 if (msg_fits_inqueue(msq, msgsz))
 866                         break;
 867
 868                 /* queue full, wait: */
 869                 if (msgflg & IPC_NOWAIT) {
 870                         err = -EAGAIN;
 871                         goto out_unlock0;
 872                 }
 873
 874                 /* enqueue the sender and prepare to block */
 875                 ss_add(msq, &s, msgsz);
 876
 877                 if (!ipc_rcu_getref(&msq->q_perm)) {
 878                         err = -EIDRM;
 879                         goto out_unlock0;
 880                 }
 881
 882                 ipc_unlock_object(&msq->q_perm);
 883                 rcu_read_unlock();
 884                 schedule();
 885
 886                 rcu_read_lock();
 887                 ipc_lock_object(&msq->q_perm);
 888
 889                 ipc_rcu_putref(&msq->q_perm, msg_rcu_free);
 890                 /* raced with RMID? */
 891                 if (!ipc_valid_object(&msq->q_perm)) {
 892                         err = -EIDRM;
 893                         goto out_unlock0;
 894                 }
 895                 ss_del(&s);
 896
 897                 if (signal_pending(current)) {
 898                         err = -ERESTARTNOHAND;
 899                         goto out_unlock0;
 900                 }
 901
 902         }
 903
 904         ipc_update_pid(&msq->q_lspid, task_tgid(current));
 905         msq->q_stime = ktime_get_real_seconds();
 906
 907         if (!pipelined_send(msq, msg, &wake_q)) {
 908                 /* no one is waiting for this message, enqueue it */
 909                 list_add_tail(&msg->m_list, &msq->q_messages);
 910                 msq->q_cbytes += msgsz;
 911                 msq->q_qnum++;
 912                 atomic_add(msgsz, &ns->msg_bytes);
 913                 atomic_inc(&ns->msg_hdrs);
 914         }
 915
 916         err = 0;
 917         msg = NULL;
 918
 919 out_unlock0:
 920         ipc_unlock_object(&msq->q_perm);
 921         wake_up_q(&wake_q);
 922 out_unlock1:
 923         rcu_read_unlock();
 924         if (msg != NULL)
 925                 free_msg(msg);
 926         return err;
 927 }
 928
 929 long ksys_msgsnd(int msqid, struct msgbuf __user *msgp, size_t msgsz,
 930                  int msgflg)
 931 {
 932         long mtype;
 933
 934         if (get_user(mtype, &msgp->mtype))
 935                 return -EFAULT;
 936         return do_msgsnd(msqid, mtype, msgp->mtext, msgsz, msgflg);
 937 }
 938
 939 SYSCALL_DEFINE4(msgsnd, int, msqid, struct msgbuf __user *, msgp, size_t, msgsz,
 940                 int, msgflg)
 941 {
 942         return ksys_msgsnd(msqid, msgp, msgsz, msgflg);
 943 }
 944
 945 #ifdef CONFIG_COMPAT
 946
 947 struct compat_msgbuf {
 948         compat_long_t mtype;
 949         char mtext[1];
 950 };
 951
 952 long compat_ksys_msgsnd(int msqid, compat_uptr_t msgp,
 953                        compat_ssize_t msgsz, int msgflg)
 954 {
 955         struct compat_msgbuf __user *up = compat_ptr(msgp);
 956         compat_long_t mtype;
 957
 958         if (get_user(mtype, &up->mtype))
 959                 return -EFAULT;
 960         return do_msgsnd(msqid, mtype, up->mtext, (ssize_t)msgsz, msgflg);
 961 }
 962
 963 COMPAT_SYSCALL_DEFINE4(msgsnd, int, msqid, compat_uptr_t, msgp,
 964                        compat_ssize_t, msgsz, int, msgflg)
 965 {
 966         return compat_ksys_msgsnd(msqid, msgp, msgsz, msgflg);
 967 }
 968 #endif
 969
 970 static inline int convert_mode(long *msgtyp, int msgflg)
 971 {
 972         if (msgflg & MSG_COPY)
 973                 return SEARCH_NUMBER;
 974         /*
 975          *  find message of correct type.
 976          *  msgtyp = 0 => get first.
 977          *  msgtyp > 0 => get first message of matching type.
 978          *  msgtyp < 0 => get message with least type must be < abs(msgtype).
 979          */
 980         if (*msgtyp == 0)
 981                 return SEARCH_ANY;
 982         if (*msgtyp < 0) {
 983                 if (*msgtyp == LONG_MIN) /* -LONG_MIN is undefined */
 984                         *msgtyp = LONG_MAX;
 985                 else
 986                         *msgtyp = -*msgtyp;
 987                 return SEARCH_LESSEQUAL;
 988         }
 989         if (msgflg & MSG_EXCEPT)
 990                 return SEARCH_NOTEQUAL;
 991         return SEARCH_EQUAL;
 992 }
 993
 994 static long do_msg_fill(void __user *dest, struct msg_msg *msg, size_t bufsz)
 995 {
 996         struct msgbuf __user *msgp = dest;
 997         size_t msgsz;
 998
 999         if (put_user(msg->m_type, &msgp->mtype))
1000                 return -EFAULT;
1001
1002         msgsz = (bufsz > msg->m_ts) ? msg->m_ts : bufsz;
1003         if (store_msg(msgp->mtext, msg, msgsz))
1004                 return -EFAULT;
1005         return msgsz;
1006 }
1007
1008 #ifdef CONFIG_CHECKPOINT_RESTORE
1009 /*
1010  * This function creates new kernel message structure, large enough to store
1011  * bufsz message bytes.
1012  */
1013 static inline struct msg_msg *prepare_copy(void __user *buf, size_t bufsz)
1014 {
1015         struct msg_msg *copy;
1016
1017         /*
1018          * Create dummy message to copy real message to.
1019          */
1020         copy = load_msg(buf, bufsz);
1021         if (!IS_ERR(copy))
1022                 copy->m_ts = bufsz;
1023         return copy;
1024 }
1025
1026 static inline void free_copy(struct msg_msg *copy)
1027 {
1028         if (copy)
1029                 free_msg(copy);
1030 }
1031 #else
1032 static inline struct msg_msg *prepare_copy(void __user *buf, size_t bufsz)
1033 {
1034         return ERR_PTR(-ENOSYS);
1035 }
1036
1037 static inline void free_copy(struct msg_msg *copy)
1038 {
1039 }
1040 #endif
1041
1042 static struct msg_msg *find_msg(struct msg_queue *msq, long *msgtyp, int mode)
1043 {
1044         struct msg_msg *msg, *found = NULL;
1045         long count = 0;
1046
1047         list_for_each_entry(msg, &msq->q_messages, m_list) {
1048                 if (testmsg(msg, *msgtyp, mode) &&
1049                     !security_msg_queue_msgrcv(&msq->q_perm, msg, current,
1050                                                *msgtyp, mode)) {
1051                         if (mode == SEARCH_LESSEQUAL && msg->m_type != 1) {
1052                                 *msgtyp = msg->m_type - 1;
1053                                 found = msg;
1054                         } else if (mode == SEARCH_NUMBER) {
1055                                 if (*msgtyp == count)
1056                                         return msg;
1057                         } else
1058                                 return msg;
1059                         count++;
1060                 }
1061         }
1062
1063         return found ?: ERR_PTR(-EAGAIN);
1064 }
1065
1066 static long do_msgrcv(int msqid, void __user *buf, size_t bufsz, long msgtyp, int msgflg,
1067                long (*msg_handler)(void __user *, struct msg_msg *, size_t))
1068 {
1069         int mode;
1070         struct msg_queue *msq;
1071         struct ipc_namespace *ns;
1072         struct msg_msg *msg, *copy = NULL;
1073         DEFINE_WAKE_Q(wake_q);
1074
1075         ns = current->nsproxy->ipc_ns;
1076
1077         if (msqid < 0 || (long) bufsz < 0)
1078                 return -EINVAL;
1079
1080         if (msgflg & MSG_COPY) {
1081                 if ((msgflg & MSG_EXCEPT) || !(msgflg & IPC_NOWAIT))
1082                         return -EINVAL;
1083                 copy = prepare_copy(buf, min_t(size_t, bufsz, ns->msg_ctlmax));
1084                 if (IS_ERR(copy))
1085                         return PTR_ERR(copy);
1086         }
1087         mode = convert_mode(&msgtyp, msgflg);
1088
1089         rcu_read_lock();
1090         msq = msq_obtain_object_check(ns, msqid);
1091         if (IS_ERR(msq)) {
1092                 rcu_read_unlock();
1093                 free_copy(copy);
1094                 return PTR_ERR(msq);
1095         }
1096
1097         for (;;) {
1098                 struct msg_receiver msr_d;
1099
1100                 msg = ERR_PTR(-EACCES);
1101                 if (ipcperms(ns, &msq->q_perm, S_IRUGO))
1102                         goto out_unlock1;
1103
1104                 ipc_lock_object(&msq->q_perm);
1105
1106                 /* raced with RMID? */
1107                 if (!ipc_valid_object(&msq->q_perm)) {
1108                         msg = ERR_PTR(-EIDRM);
1109                         goto out_unlock0;
1110                 }
1111
1112                 msg = find_msg(msq, &msgtyp, mode);
1113                 if (!IS_ERR(msg)) {
1114                         /*
1115                          * Found a suitable message.
1116                          * Unlink it from the queue.
1117                          */
1118                         if ((bufsz < msg->m_ts) && !(msgflg & MSG_NOERROR)) {
1119                                 msg = ERR_PTR(-E2BIG);
1120                                 goto out_unlock0;
1121                         }
1122                         /*
1123                          * If we are copying, then do not unlink message and do
1124                          * not update queue parameters.
1125                          */
1126                         if (msgflg & MSG_COPY) {
1127                                 msg = copy_msg(msg, copy);
1128                                 goto out_unlock0;
1129                         }
1130
1131                         list_del(&msg->m_list);
1132                         msq->q_qnum--;
1133                         msq->q_rtime = ktime_get_real_seconds();
1134                         ipc_update_pid(&msq->q_lrpid, task_tgid(current));
1135                         msq->q_cbytes -= msg->m_ts;
1136                         atomic_sub(msg->m_ts, &ns->msg_bytes);
1137                         atomic_dec(&ns->msg_hdrs);
1138                         ss_wakeup(msq, &wake_q, false);
1139
1140                         goto out_unlock0;
1141                 }
1142
1143                 /* No message waiting. Wait for a message */
1144                 if (msgflg & IPC_NOWAIT) {
1145                         msg = ERR_PTR(-ENOMSG);
1146                         goto out_unlock0;
1147                 }
1148
1149                 list_add_tail(&msr_d.r_list, &msq->q_receivers);
1150                 msr_d.r_tsk = current;
1151                 msr_d.r_msgtype = msgtyp;
1152                 msr_d.r_mode = mode;
1153                 if (msgflg & MSG_NOERROR)
1154                         msr_d.r_maxsize = INT_MAX;
1155                 else
1156                         msr_d.r_maxsize = bufsz;
1157                 msr_d.r_msg = ERR_PTR(-EAGAIN);
1158                 __set_current_state(TASK_INTERRUPTIBLE);
1159
1160                 ipc_unlock_object(&msq->q_perm);
1161                 rcu_read_unlock();
1162                 schedule();
1163
1164                 /*
1165                  * Lockless receive, part 1:
1166                  * We don't hold a reference to the queue and getting a
1167                  * reference would defeat the idea of a lockless operation,
1168                  * thus the code relies on rcu to guarantee the existence of
1169                  * msq:
1170                  * Prior to destruction, expunge_all(-EIRDM) changes r_msg.
1171                  * Thus if r_msg is -EAGAIN, then the queue not yet destroyed.
1172                  */
1173                 rcu_read_lock();
1174
1175                 /*
1176                  * Lockless receive, part 2:
1177                  * The work in pipelined_send() and expunge_all():
1178                  * - Set pointer to message
1179                  * - Queue the receiver task for later wakeup
1180                  * - Wake up the process after the lock is dropped.
1181                  *
1182                  * Should the process wake up before this wakeup (due to a
1183                  * signal) it will either see the message and continue ...
1184                  */
1185                 msg = READ_ONCE(msr_d.r_msg);
1186                 if (msg != ERR_PTR(-EAGAIN))
1187                         goto out_unlock1;
1188
1189                  /*
1190                   * ... or see -EAGAIN, acquire the lock to check the message
1191                   * again.
1192                   */
1193                 ipc_lock_object(&msq->q_perm);
1194
1195                 msg = msr_d.r_msg;
1196                 if (msg != ERR_PTR(-EAGAIN))
1197                         goto out_unlock0;
1198
1199                 list_del(&msr_d.r_list);
1200                 if (signal_pending(current)) {
1201                         msg = ERR_PTR(-ERESTARTNOHAND);
1202                         goto out_unlock0;
1203                 }
1204
1205                 ipc_unlock_object(&msq->q_perm);
1206         }
1207
1208 out_unlock0:
1209         ipc_unlock_object(&msq->q_perm);
1210         wake_up_q(&wake_q);
1211 out_unlock1:
1212         rcu_read_unlock();
1213         if (IS_ERR(msg)) {
1214                 free_copy(copy);
1215                 return PTR_ERR(msg);
1216         }
1217
1218         bufsz = msg_handler(buf, msg, bufsz);
1219         free_msg(msg);
1220
1221         return bufsz;
1222 }
1223
1224 long ksys_msgrcv(int msqid, struct msgbuf __user *msgp, size_t msgsz,
1225                  long msgtyp, int msgflg)
1226 {
1227         return do_msgrcv(msqid, msgp, msgsz, msgtyp, msgflg, do_msg_fill);
1228 }
1229
1230 SYSCALL_DEFINE5(msgrcv, int, msqid, struct msgbuf __user *, msgp, size_t, msgsz,
1231                 long, msgtyp, int, msgflg)
1232 {
1233         return ksys_msgrcv(msqid, msgp, msgsz, msgtyp, msgflg);
1234 }
1235
1236 #ifdef CONFIG_COMPAT
1237 static long compat_do_msg_fill(void __user *dest, struct msg_msg *msg, size_t bufsz)
1238 {
1239         struct compat_msgbuf __user *msgp = dest;
1240         size_t msgsz;
1241
1242         if (put_user(msg->m_type, &msgp->mtype))
1243                 return -EFAULT;
1244
1245         msgsz = (bufsz > msg->m_ts) ? msg->m_ts : bufsz;
1246         if (store_msg(msgp->mtext, msg, msgsz))
1247                 return -EFAULT;
1248         return msgsz;
1249 }
1250
1251 long compat_ksys_msgrcv(int msqid, compat_uptr_t msgp, compat_ssize_t msgsz,
1252                         compat_long_t msgtyp, int msgflg)
1253 {
1254         return do_msgrcv(msqid, compat_ptr(msgp), (ssize_t)msgsz, (long)msgtyp,
1255                          msgflg, compat_do_msg_fill);
1256 }
1257
1258 COMPAT_SYSCALL_DEFINE5(msgrcv, int, msqid, compat_uptr_t, msgp,
1259                        compat_ssize_t, msgsz, compat_long_t, msgtyp,
1260                        int, msgflg)
1261 {
1262         return compat_ksys_msgrcv(msqid, msgp, msgsz, msgtyp, msgflg);
1263 }
1264 #endif
1265
1266 void msg_init_ns(struct ipc_namespace *ns)
1267 {
1268         ns->msg_ctlmax = MSGMAX;
1269         ns->msg_ctlmnb = MSGMNB;
1270         ns->msg_ctlmni = MSGMNI;
1271
1272         atomic_set(&ns->msg_bytes, 0);
1273         atomic_set(&ns->msg_hdrs, 0);
1274         ipc_init_ids(&ns->ids[IPC_MSG_IDS]);
1275 }
1276
1277 #ifdef CONFIG_IPC_NS
1278 void msg_exit_ns(struct ipc_namespace *ns)
1279 {
1280         free_ipcs(ns, &msg_ids(ns), freeque);
1281         idr_destroy(&ns->ids[IPC_MSG_IDS].ipcs_idr);
1282         rhashtable_destroy(&ns->ids[IPC_MSG_IDS].key_ht);
1283 }
1284 #endif
1285
1286 #ifdef CONFIG_PROC_FS
1287 static int sysvipc_msg_proc_show(struct seq_file *s, void *it)
1288 {
1289         struct pid_namespace *pid_ns = ipc_seq_pid_ns(s);
1290         struct user_namespace *user_ns = seq_user_ns(s);
1291         struct kern_ipc_perm *ipcp = it;
1292         struct msg_queue *msq = container_of(ipcp, struct msg_queue, q_perm);
1293
1294         seq_printf(s,
1295                    "%10d %10d  %4o  %10lu %10lu %5u %5u %5u %5u %5u %5u %10llu %10llu %10llu\n",
1296                    msq->q_perm.key,
1297                    msq->q_perm.id,
1298                    msq->q_perm.mode,
1299                    msq->q_cbytes,
1300                    msq->q_qnum,
1301                    pid_nr_ns(msq->q_lspid, pid_ns),
1302                    pid_nr_ns(msq->q_lrpid, pid_ns),
1303                    from_kuid_munged(user_ns, msq->q_perm.uid),
1304                    from_kgid_munged(user_ns, msq->q_perm.gid),
1305                    from_kuid_munged(user_ns, msq->q_perm.cuid),
1306                    from_kgid_munged(user_ns, msq->q_perm.cgid),
1307                    msq->q_stime,
1308                    msq->q_rtime,
1309                    msq->q_ctime);
1310
1311         return 0;
1312 }
1313 #endif
1314
1315 void __init msg_init(void)
1316 {
1317         msg_init_ns(&init_ipc_ns);
1318
1319         ipc_init_proc_interface("sysvipc/msg",
1320                                 "       key      msqid perms      cbytes       qnum lspid lrpid   uid   gid  cuid  cgid      stime      rtime      ctime\n",
1321                                 IPC_MSG_IDS, sysvipc_msg_proc_show);
1322 }