linux/ipc/msg.c
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   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 */
  48struct 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/*
  65 * MSG_BARRIER Locking:
  66 *
  67 * Similar to the optimization used in ipc/mqueue.c, one syscall return path
  68 * does not acquire any locks when it sees that a message exists in
  69 * msg_receiver.r_msg. Therefore r_msg is set using smp_store_release()
  70 * and accessed using READ_ONCE()+smp_acquire__after_ctrl_dep(). In addition,
  71 * wake_q_add_safe() is used. See ipc/mqueue.c for more details
  72 */
  73
  74/* one msg_receiver structure for each sleeping receiver */
  75struct msg_receiver {
  76        struct list_head        r_list;
  77        struct task_struct      *r_tsk;
  78
  79        int                     r_mode;
  80        long                    r_msgtype;
  81        long                    r_maxsize;
  82
  83        struct msg_msg          *r_msg;
  84};
  85
  86/* one msg_sender for each sleeping sender */
  87struct msg_sender {
  88        struct list_head        list;
  89        struct task_struct      *tsk;
  90        size_t                  msgsz;
  91};
  92
  93#define SEARCH_ANY              1
  94#define SEARCH_EQUAL            2
  95#define SEARCH_NOTEQUAL         3
  96#define SEARCH_LESSEQUAL        4
  97#define SEARCH_NUMBER           5
  98
  99#define msg_ids(ns)     ((ns)->ids[IPC_MSG_IDS])
 100
 101static inline struct msg_queue *msq_obtain_object(struct ipc_namespace *ns, int id)
 102{
 103        struct kern_ipc_perm *ipcp = ipc_obtain_object_idr(&msg_ids(ns), id);
 104
 105        if (IS_ERR(ipcp))
 106                return ERR_CAST(ipcp);
 107
 108        return container_of(ipcp, struct msg_queue, q_perm);
 109}
 110
 111static inline struct msg_queue *msq_obtain_object_check(struct ipc_namespace *ns,
 112                                                        int id)
 113{
 114        struct kern_ipc_perm *ipcp = ipc_obtain_object_check(&msg_ids(ns), id);
 115
 116        if (IS_ERR(ipcp))
 117                return ERR_CAST(ipcp);
 118
 119        return container_of(ipcp, struct msg_queue, q_perm);
 120}
 121
 122static inline void msg_rmid(struct ipc_namespace *ns, struct msg_queue *s)
 123{
 124        ipc_rmid(&msg_ids(ns), &s->q_perm);
 125}
 126
 127static void msg_rcu_free(struct rcu_head *head)
 128{
 129        struct kern_ipc_perm *p = container_of(head, struct kern_ipc_perm, rcu);
 130        struct msg_queue *msq = container_of(p, struct msg_queue, q_perm);
 131
 132        security_msg_queue_free(&msq->q_perm);
 133        kvfree(msq);
 134}
 135
 136/**
 137 * newque - Create a new msg queue
 138 * @ns: namespace
 139 * @params: ptr to the structure that contains the key and msgflg
 140 *
 141 * Called with msg_ids.rwsem held (writer)
 142 */
 143static int newque(struct ipc_namespace *ns, struct ipc_params *params)
 144{
 145        struct msg_queue *msq;
 146        int retval;
 147        key_t key = params->key;
 148        int msgflg = params->flg;
 149
 150        msq = kvmalloc(sizeof(*msq), GFP_KERNEL);
 151        if (unlikely(!msq))
 152                return -ENOMEM;
 153
 154        msq->q_perm.mode = msgflg & S_IRWXUGO;
 155        msq->q_perm.key = key;
 156
 157        msq->q_perm.security = NULL;
 158        retval = security_msg_queue_alloc(&msq->q_perm);
 159        if (retval) {
 160                kvfree(msq);
 161                return retval;
 162        }
 163
 164        msq->q_stime = msq->q_rtime = 0;
 165        msq->q_ctime = ktime_get_real_seconds();
 166        msq->q_cbytes = msq->q_qnum = 0;
 167        msq->q_qbytes = ns->msg_ctlmnb;
 168        msq->q_lspid = msq->q_lrpid = NULL;
 169        INIT_LIST_HEAD(&msq->q_messages);
 170        INIT_LIST_HEAD(&msq->q_receivers);
 171        INIT_LIST_HEAD(&msq->q_senders);
 172
 173        /* ipc_addid() locks msq upon success. */
 174        retval = ipc_addid(&msg_ids(ns), &msq->q_perm, ns->msg_ctlmni);
 175        if (retval < 0) {
 176                ipc_rcu_putref(&msq->q_perm, msg_rcu_free);
 177                return retval;
 178        }
 179
 180        ipc_unlock_object(&msq->q_perm);
 181        rcu_read_unlock();
 182
 183        return msq->q_perm.id;
 184}
 185
 186static inline bool msg_fits_inqueue(struct msg_queue *msq, size_t msgsz)
 187{
 188        return msgsz + msq->q_cbytes <= msq->q_qbytes &&
 189                1 + msq->q_qnum <= msq->q_qbytes;
 190}
 191
 192static inline void ss_add(struct msg_queue *msq,
 193                          struct msg_sender *mss, size_t msgsz)
 194{
 195        mss->tsk = current;
 196        mss->msgsz = msgsz;
 197        /*
 198         * No memory barrier required: we did ipc_lock_object(),
 199         * and the waker obtains that lock before calling wake_q_add().
 200         */
 201        __set_current_state(TASK_INTERRUPTIBLE);
 202        list_add_tail(&mss->list, &msq->q_senders);
 203}
 204
 205static inline void ss_del(struct msg_sender *mss)
 206{
 207        if (mss->list.next)
 208                list_del(&mss->list);
 209}
 210
 211static void ss_wakeup(struct msg_queue *msq,
 212                      struct wake_q_head *wake_q, bool kill)
 213{
 214        struct msg_sender *mss, *t;
 215        struct task_struct *stop_tsk = NULL;
 216        struct list_head *h = &msq->q_senders;
 217
 218        list_for_each_entry_safe(mss, t, h, list) {
 219                if (kill)
 220                        mss->list.next = NULL;
 221
 222                /*
 223                 * Stop at the first task we don't wakeup,
 224                 * we've already iterated the original
 225                 * sender queue.
 226                 */
 227                else if (stop_tsk == mss->tsk)
 228                        break;
 229                /*
 230                 * We are not in an EIDRM scenario here, therefore
 231                 * verify that we really need to wakeup the task.
 232                 * To maintain current semantics and wakeup order,
 233                 * move the sender to the tail on behalf of the
 234                 * blocked task.
 235                 */
 236                else if (!msg_fits_inqueue(msq, mss->msgsz)) {
 237                        if (!stop_tsk)
 238                                stop_tsk = mss->tsk;
 239
 240                        list_move_tail(&mss->list, &msq->q_senders);
 241                        continue;
 242                }
 243
 244                wake_q_add(wake_q, mss->tsk);
 245        }
 246}
 247
 248static void expunge_all(struct msg_queue *msq, int res,
 249                        struct wake_q_head *wake_q)
 250{
 251        struct msg_receiver *msr, *t;
 252
 253        list_for_each_entry_safe(msr, t, &msq->q_receivers, r_list) {
 254                struct task_struct *r_tsk;
 255
 256                r_tsk = get_task_struct(msr->r_tsk);
 257
 258                /* see MSG_BARRIER for purpose/pairing */
 259                smp_store_release(&msr->r_msg, ERR_PTR(res));
 260                wake_q_add_safe(wake_q, r_tsk);
 261        }
 262}
 263
 264/*
 265 * freeque() wakes up waiters on the sender and receiver waiting queue,
 266 * removes the message queue from message queue ID IDR, and cleans up all the
 267 * messages associated with this queue.
 268 *
 269 * msg_ids.rwsem (writer) and the spinlock for this message queue are held
 270 * before freeque() is called. msg_ids.rwsem remains locked on exit.
 271 */
 272static void freeque(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp)
 273        __releases(RCU)
 274        __releases(&msq->q_perm)
 275{
 276        struct msg_msg *msg, *t;
 277        struct msg_queue *msq = container_of(ipcp, struct msg_queue, q_perm);
 278        DEFINE_WAKE_Q(wake_q);
 279
 280        expunge_all(msq, -EIDRM, &wake_q);
 281        ss_wakeup(msq, &wake_q, true);
 282        msg_rmid(ns, msq);
 283        ipc_unlock_object(&msq->q_perm);
 284        wake_up_q(&wake_q);
 285        rcu_read_unlock();
 286
 287        list_for_each_entry_safe(msg, t, &msq->q_messages, m_list) {
 288                atomic_dec(&ns->msg_hdrs);
 289                free_msg(msg);
 290        }
 291        atomic_sub(msq->q_cbytes, &ns->msg_bytes);
 292        ipc_update_pid(&msq->q_lspid, NULL);
 293        ipc_update_pid(&msq->q_lrpid, NULL);
 294        ipc_rcu_putref(&msq->q_perm, msg_rcu_free);
 295}
 296
 297long ksys_msgget(key_t key, int msgflg)
 298{
 299        struct ipc_namespace *ns;
 300        static const struct ipc_ops msg_ops = {
 301                .getnew = newque,
 302                .associate = security_msg_queue_associate,
 303        };
 304        struct ipc_params msg_params;
 305
 306        ns = current->nsproxy->ipc_ns;
 307
 308        msg_params.key = key;
 309        msg_params.flg = msgflg;
 310
 311        return ipcget(ns, &msg_ids(ns), &msg_ops, &msg_params);
 312}
 313
 314SYSCALL_DEFINE2(msgget, key_t, key, int, msgflg)
 315{
 316        return ksys_msgget(key, msgflg);
 317}
 318
 319static inline unsigned long
 320copy_msqid_to_user(void __user *buf, struct msqid64_ds *in, int version)
 321{
 322        switch (version) {
 323        case IPC_64:
 324                return copy_to_user(buf, in, sizeof(*in));
 325        case IPC_OLD:
 326        {
 327                struct msqid_ds out;
 328
 329                memset(&out, 0, sizeof(out));
 330
 331                ipc64_perm_to_ipc_perm(&in->msg_perm, &out.msg_perm);
 332
 333                out.msg_stime           = in->msg_stime;
 334                out.msg_rtime           = in->msg_rtime;
 335                out.msg_ctime           = in->msg_ctime;
 336
 337                if (in->msg_cbytes > USHRT_MAX)
 338                        out.msg_cbytes  = USHRT_MAX;
 339                else
 340                        out.msg_cbytes  = in->msg_cbytes;
 341                out.msg_lcbytes         = in->msg_cbytes;
 342
 343                if (in->msg_qnum > USHRT_MAX)
 344                        out.msg_qnum    = USHRT_MAX;
 345                else
 346                        out.msg_qnum    = in->msg_qnum;
 347
 348                if (in->msg_qbytes > USHRT_MAX)
 349                        out.msg_qbytes  = USHRT_MAX;
 350                else
 351                        out.msg_qbytes  = in->msg_qbytes;
 352                out.msg_lqbytes         = in->msg_qbytes;
 353
 354                out.msg_lspid           = in->msg_lspid;
 355                out.msg_lrpid           = in->msg_lrpid;
 356
 357                return copy_to_user(buf, &out, sizeof(out));
 358        }
 359        default:
 360                return -EINVAL;
 361        }
 362}
 363
 364static inline unsigned long
 365copy_msqid_from_user(struct msqid64_ds *out, void __user *buf, int version)
 366{
 367        switch (version) {
 368        case IPC_64:
 369                if (copy_from_user(out, buf, sizeof(*out)))
 370                        return -EFAULT;
 371                return 0;
 372        case IPC_OLD:
 373        {
 374                struct msqid_ds tbuf_old;
 375
 376                if (copy_from_user(&tbuf_old, buf, sizeof(tbuf_old)))
 377                        return -EFAULT;
 378
 379                out->msg_perm.uid       = tbuf_old.msg_perm.uid;
 380                out->msg_perm.gid       = tbuf_old.msg_perm.gid;
 381                out->msg_perm.mode      = tbuf_old.msg_perm.mode;
 382
 383                if (tbuf_old.msg_qbytes == 0)
 384                        out->msg_qbytes = tbuf_old.msg_lqbytes;
 385                else
 386                        out->msg_qbytes = tbuf_old.msg_qbytes;
 387
 388                return 0;
 389        }
 390        default:
 391                return -EINVAL;
 392        }
 393}
 394
 395/*
 396 * This function handles some msgctl commands which require the rwsem
 397 * to be held in write mode.
 398 * NOTE: no locks must be held, the rwsem is taken inside this function.
 399 */
 400static int msgctl_down(struct ipc_namespace *ns, int msqid, int cmd,
 401                        struct ipc64_perm *perm, int msg_qbytes)
 402{
 403        struct kern_ipc_perm *ipcp;
 404        struct msg_queue *msq;
 405        int err;
 406
 407        down_write(&msg_ids(ns).rwsem);
 408        rcu_read_lock();
 409
 410        ipcp = ipcctl_obtain_check(ns, &msg_ids(ns), msqid, cmd,
 411                                      perm, msg_qbytes);
 412        if (IS_ERR(ipcp)) {
 413                err = PTR_ERR(ipcp);
 414                goto out_unlock1;
 415        }
 416
 417        msq = container_of(ipcp, struct msg_queue, q_perm);
 418
 419        err = security_msg_queue_msgctl(&msq->q_perm, cmd);
 420        if (err)
 421                goto out_unlock1;
 422
 423        switch (cmd) {
 424        case IPC_RMID:
 425                ipc_lock_object(&msq->q_perm);
 426                /* freeque unlocks the ipc object and rcu */
 427                freeque(ns, ipcp);
 428                goto out_up;
 429        case IPC_SET:
 430        {
 431                DEFINE_WAKE_Q(wake_q);
 432
 433                if (msg_qbytes > ns->msg_ctlmnb &&
 434                    !capable(CAP_SYS_RESOURCE)) {
 435                        err = -EPERM;
 436                        goto out_unlock1;
 437                }
 438
 439                ipc_lock_object(&msq->q_perm);
 440                err = ipc_update_perm(perm, ipcp);
 441                if (err)
 442                        goto out_unlock0;
 443
 444                msq->q_qbytes = msg_qbytes;
 445
 446                msq->q_ctime = ktime_get_real_seconds();
 447                /*
 448                 * Sleeping receivers might be excluded by
 449                 * stricter permissions.
 450                 */
 451                expunge_all(msq, -EAGAIN, &wake_q);
 452                /*
 453                 * Sleeping senders might be able to send
 454                 * due to a larger queue size.
 455                 */
 456                ss_wakeup(msq, &wake_q, false);
 457                ipc_unlock_object(&msq->q_perm);
 458                wake_up_q(&wake_q);
 459
 460                goto out_unlock1;
 461        }
 462        default:
 463                err = -EINVAL;
 464                goto out_unlock1;
 465        }
 466
 467out_unlock0:
 468        ipc_unlock_object(&msq->q_perm);
 469out_unlock1:
 470        rcu_read_unlock();
 471out_up:
 472        up_write(&msg_ids(ns).rwsem);
 473        return err;
 474}
 475
 476static int msgctl_info(struct ipc_namespace *ns, int msqid,
 477                         int cmd, struct msginfo *msginfo)
 478{
 479        int err;
 480        int max_idx;
 481
 482        /*
 483         * We must not return kernel stack data.
 484         * due to padding, it's not enough
 485         * to set all member fields.
 486         */
 487        err = security_msg_queue_msgctl(NULL, cmd);
 488        if (err)
 489                return err;
 490
 491        memset(msginfo, 0, sizeof(*msginfo));
 492        msginfo->msgmni = ns->msg_ctlmni;
 493        msginfo->msgmax = ns->msg_ctlmax;
 494        msginfo->msgmnb = ns->msg_ctlmnb;
 495        msginfo->msgssz = MSGSSZ;
 496        msginfo->msgseg = MSGSEG;
 497        down_read(&msg_ids(ns).rwsem);
 498        if (cmd == MSG_INFO) {
 499                msginfo->msgpool = msg_ids(ns).in_use;
 500                msginfo->msgmap = atomic_read(&ns->msg_hdrs);
 501                msginfo->msgtql = atomic_read(&ns->msg_bytes);
 502        } else {
 503                msginfo->msgmap = MSGMAP;
 504                msginfo->msgpool = MSGPOOL;
 505                msginfo->msgtql = MSGTQL;
 506        }
 507        max_idx = ipc_get_maxidx(&msg_ids(ns));
 508        up_read(&msg_ids(ns).rwsem);
 509        return (max_idx < 0) ? 0 : max_idx;
 510}
 511
 512static int msgctl_stat(struct ipc_namespace *ns, int msqid,
 513                         int cmd, struct msqid64_ds *p)
 514{
 515        struct msg_queue *msq;
 516        int err;
 517
 518        memset(p, 0, sizeof(*p));
 519
 520        rcu_read_lock();
 521        if (cmd == MSG_STAT || cmd == MSG_STAT_ANY) {
 522                msq = msq_obtain_object(ns, msqid);
 523                if (IS_ERR(msq)) {
 524                        err = PTR_ERR(msq);
 525                        goto out_unlock;
 526                }
 527        } else { /* IPC_STAT */
 528                msq = msq_obtain_object_check(ns, msqid);
 529                if (IS_ERR(msq)) {
 530                        err = PTR_ERR(msq);
 531                        goto out_unlock;
 532                }
 533        }
 534
 535        /* see comment for SHM_STAT_ANY */
 536        if (cmd == MSG_STAT_ANY)
 537                audit_ipc_obj(&msq->q_perm);
 538        else {
 539                err = -EACCES;
 540                if (ipcperms(ns, &msq->q_perm, S_IRUGO))
 541                        goto out_unlock;
 542        }
 543
 544        err = security_msg_queue_msgctl(&msq->q_perm, cmd);
 545        if (err)
 546                goto out_unlock;
 547
 548        ipc_lock_object(&msq->q_perm);
 549
 550        if (!ipc_valid_object(&msq->q_perm)) {
 551                ipc_unlock_object(&msq->q_perm);
 552                err = -EIDRM;
 553                goto out_unlock;
 554        }
 555
 556        kernel_to_ipc64_perm(&msq->q_perm, &p->msg_perm);
 557        p->msg_stime  = msq->q_stime;
 558        p->msg_rtime  = msq->q_rtime;
 559        p->msg_ctime  = msq->q_ctime;
 560#ifndef CONFIG_64BIT
 561        p->msg_stime_high = msq->q_stime >> 32;
 562        p->msg_rtime_high = msq->q_rtime >> 32;
 563        p->msg_ctime_high = msq->q_ctime >> 32;
 564#endif
 565        p->msg_cbytes = msq->q_cbytes;
 566        p->msg_qnum   = msq->q_qnum;
 567        p->msg_qbytes = msq->q_qbytes;
 568        p->msg_lspid  = pid_vnr(msq->q_lspid);
 569        p->msg_lrpid  = pid_vnr(msq->q_lrpid);
 570
 571        if (cmd == IPC_STAT) {
 572                /*
 573                 * As defined in SUS:
 574                 * Return 0 on success
 575                 */
 576                err = 0;
 577        } else {
 578                /*
 579                 * MSG_STAT and MSG_STAT_ANY (both Linux specific)
 580                 * Return the full id, including the sequence number
 581                 */
 582                err = msq->q_perm.id;
 583        }
 584
 585        ipc_unlock_object(&msq->q_perm);
 586out_unlock:
 587        rcu_read_unlock();
 588        return err;
 589}
 590
 591static long ksys_msgctl(int msqid, int cmd, struct msqid_ds __user *buf, int version)
 592{
 593        struct ipc_namespace *ns;
 594        struct msqid64_ds msqid64;
 595        int err;
 596
 597        if (msqid < 0 || cmd < 0)
 598                return -EINVAL;
 599
 600        ns = current->nsproxy->ipc_ns;
 601
 602        switch (cmd) {
 603        case IPC_INFO:
 604        case MSG_INFO: {
 605                struct msginfo msginfo;
 606                err = msgctl_info(ns, msqid, cmd, &msginfo);
 607                if (err < 0)
 608                        return err;
 609                if (copy_to_user(buf, &msginfo, sizeof(struct msginfo)))
 610                        err = -EFAULT;
 611                return err;
 612        }
 613        case MSG_STAT:  /* msqid is an index rather than a msg queue id */
 614        case MSG_STAT_ANY:
 615        case IPC_STAT:
 616                err = msgctl_stat(ns, msqid, cmd, &msqid64);
 617                if (err < 0)
 618                        return err;
 619                if (copy_msqid_to_user(buf, &msqid64, version))
 620                        err = -EFAULT;
 621                return err;
 622        case IPC_SET:
 623                if (copy_msqid_from_user(&msqid64, buf, version))
 624                        return -EFAULT;
 625                return msgctl_down(ns, msqid, cmd, &msqid64.msg_perm,
 626                                   msqid64.msg_qbytes);
 627        case IPC_RMID:
 628                return msgctl_down(ns, msqid, cmd, NULL, 0);
 629        default:
 630                return  -EINVAL;
 631        }
 632}
 633
 634SYSCALL_DEFINE3(msgctl, int, msqid, int, cmd, struct msqid_ds __user *, buf)
 635{
 636        return ksys_msgctl(msqid, cmd, buf, IPC_64);
 637}
 638
 639#ifdef CONFIG_ARCH_WANT_IPC_PARSE_VERSION
 640long ksys_old_msgctl(int msqid, int cmd, struct msqid_ds __user *buf)
 641{
 642        int version = ipc_parse_version(&cmd);
 643
 644        return ksys_msgctl(msqid, cmd, buf, version);
 645}
 646
 647SYSCALL_DEFINE3(old_msgctl, int, msqid, int, cmd, struct msqid_ds __user *, buf)
 648{
 649        return ksys_old_msgctl(msqid, cmd, buf);
 650}
 651#endif
 652
 653#ifdef CONFIG_COMPAT
 654
 655struct compat_msqid_ds {
 656        struct compat_ipc_perm msg_perm;
 657        compat_uptr_t msg_first;
 658        compat_uptr_t msg_last;
 659        old_time32_t msg_stime;
 660        old_time32_t msg_rtime;
 661        old_time32_t msg_ctime;
 662        compat_ulong_t msg_lcbytes;
 663        compat_ulong_t msg_lqbytes;
 664        unsigned short msg_cbytes;
 665        unsigned short msg_qnum;
 666        unsigned short msg_qbytes;
 667        compat_ipc_pid_t msg_lspid;
 668        compat_ipc_pid_t msg_lrpid;
 669};
 670
 671static int copy_compat_msqid_from_user(struct msqid64_ds *out, void __user *buf,
 672                                        int version)
 673{
 674        memset(out, 0, sizeof(*out));
 675        if (version == IPC_64) {
 676                struct compat_msqid64_ds __user *p = buf;
 677                if (get_compat_ipc64_perm(&out->msg_perm, &p->msg_perm))
 678                        return -EFAULT;
 679                if (get_user(out->msg_qbytes, &p->msg_qbytes))
 680                        return -EFAULT;
 681        } else {
 682                struct compat_msqid_ds __user *p = buf;
 683                if (get_compat_ipc_perm(&out->msg_perm, &p->msg_perm))
 684                        return -EFAULT;
 685                if (get_user(out->msg_qbytes, &p->msg_qbytes))
 686                        return -EFAULT;
 687        }
 688        return 0;
 689}
 690
 691static int copy_compat_msqid_to_user(void __user *buf, struct msqid64_ds *in,
 692                                        int version)
 693{
 694        if (version == IPC_64) {
 695                struct compat_msqid64_ds v;
 696                memset(&v, 0, sizeof(v));
 697                to_compat_ipc64_perm(&v.msg_perm, &in->msg_perm);
 698                v.msg_stime      = lower_32_bits(in->msg_stime);
 699                v.msg_stime_high = upper_32_bits(in->msg_stime);
 700                v.msg_rtime      = lower_32_bits(in->msg_rtime);
 701                v.msg_rtime_high = upper_32_bits(in->msg_rtime);
 702                v.msg_ctime      = lower_32_bits(in->msg_ctime);
 703                v.msg_ctime_high = upper_32_bits(in->msg_ctime);
 704                v.msg_cbytes = in->msg_cbytes;
 705                v.msg_qnum = in->msg_qnum;
 706                v.msg_qbytes = in->msg_qbytes;
 707                v.msg_lspid = in->msg_lspid;
 708                v.msg_lrpid = in->msg_lrpid;
 709                return copy_to_user(buf, &v, sizeof(v));
 710        } else {
 711                struct compat_msqid_ds v;
 712                memset(&v, 0, sizeof(v));
 713                to_compat_ipc_perm(&v.msg_perm, &in->msg_perm);
 714                v.msg_stime = in->msg_stime;
 715                v.msg_rtime = in->msg_rtime;
 716                v.msg_ctime = in->msg_ctime;
 717                v.msg_cbytes = in->msg_cbytes;
 718                v.msg_qnum = in->msg_qnum;
 719                v.msg_qbytes = in->msg_qbytes;
 720                v.msg_lspid = in->msg_lspid;
 721                v.msg_lrpid = in->msg_lrpid;
 722                return copy_to_user(buf, &v, sizeof(v));
 723        }
 724}
 725
 726static long compat_ksys_msgctl(int msqid, int cmd, void __user *uptr, int version)
 727{
 728        struct ipc_namespace *ns;
 729        int err;
 730        struct msqid64_ds msqid64;
 731
 732        ns = current->nsproxy->ipc_ns;
 733
 734        if (msqid < 0 || cmd < 0)
 735                return -EINVAL;
 736
 737        switch (cmd & (~IPC_64)) {
 738        case IPC_INFO:
 739        case MSG_INFO: {
 740                struct msginfo msginfo;
 741                err = msgctl_info(ns, msqid, cmd, &msginfo);
 742                if (err < 0)
 743                        return err;
 744                if (copy_to_user(uptr, &msginfo, sizeof(struct msginfo)))
 745                        err = -EFAULT;
 746                return err;
 747        }
 748        case IPC_STAT:
 749        case MSG_STAT:
 750        case MSG_STAT_ANY:
 751                err = msgctl_stat(ns, msqid, cmd, &msqid64);
 752                if (err < 0)
 753                        return err;
 754                if (copy_compat_msqid_to_user(uptr, &msqid64, version))
 755                        err = -EFAULT;
 756                return err;
 757        case IPC_SET:
 758                if (copy_compat_msqid_from_user(&msqid64, uptr, version))
 759                        return -EFAULT;
 760                return msgctl_down(ns, msqid, cmd, &msqid64.msg_perm, msqid64.msg_qbytes);
 761        case IPC_RMID:
 762                return msgctl_down(ns, msqid, cmd, NULL, 0);
 763        default:
 764                return -EINVAL;
 765        }
 766}
 767
 768COMPAT_SYSCALL_DEFINE3(msgctl, int, msqid, int, cmd, void __user *, uptr)
 769{
 770        return compat_ksys_msgctl(msqid, cmd, uptr, IPC_64);
 771}
 772
 773#ifdef CONFIG_ARCH_WANT_COMPAT_IPC_PARSE_VERSION
 774long compat_ksys_old_msgctl(int msqid, int cmd, void __user *uptr)
 775{
 776        int version = compat_ipc_parse_version(&cmd);
 777
 778        return compat_ksys_msgctl(msqid, cmd, uptr, version);
 779}
 780
 781COMPAT_SYSCALL_DEFINE3(old_msgctl, int, msqid, int, cmd, void __user *, uptr)
 782{
 783        return compat_ksys_old_msgctl(msqid, cmd, uptr);
 784}
 785#endif
 786#endif
 787
 788static int testmsg(struct msg_msg *msg, long type, int mode)
 789{
 790        switch (mode) {
 791        case SEARCH_ANY:
 792        case SEARCH_NUMBER:
 793                return 1;
 794        case SEARCH_LESSEQUAL:
 795                if (msg->m_type <= type)
 796                        return 1;
 797                break;
 798        case SEARCH_EQUAL:
 799                if (msg->m_type == type)
 800                        return 1;
 801                break;
 802        case SEARCH_NOTEQUAL:
 803                if (msg->m_type != type)
 804                        return 1;
 805                break;
 806        }
 807        return 0;
 808}
 809
 810static inline int pipelined_send(struct msg_queue *msq, struct msg_msg *msg,
 811                                 struct wake_q_head *wake_q)
 812{
 813        struct msg_receiver *msr, *t;
 814
 815        list_for_each_entry_safe(msr, t, &msq->q_receivers, r_list) {
 816                if (testmsg(msg, msr->r_msgtype, msr->r_mode) &&
 817                    !security_msg_queue_msgrcv(&msq->q_perm, msg, msr->r_tsk,
 818                                               msr->r_msgtype, msr->r_mode)) {
 819
 820                        list_del(&msr->r_list);
 821                        if (msr->r_maxsize < msg->m_ts) {
 822                                wake_q_add(wake_q, msr->r_tsk);
 823
 824                                /* See expunge_all regarding memory barrier */
 825                                smp_store_release(&msr->r_msg, ERR_PTR(-E2BIG));
 826                        } else {
 827                                ipc_update_pid(&msq->q_lrpid, task_pid(msr->r_tsk));
 828                                msq->q_rtime = ktime_get_real_seconds();
 829
 830                                wake_q_add(wake_q, msr->r_tsk);
 831
 832                                /* See expunge_all regarding memory barrier */
 833                                smp_store_release(&msr->r_msg, msg);
 834                                return 1;
 835                        }
 836                }
 837        }
 838
 839        return 0;
 840}
 841
 842static long do_msgsnd(int msqid, long mtype, void __user *mtext,
 843                size_t msgsz, int msgflg)
 844{
 845        struct msg_queue *msq;
 846        struct msg_msg *msg;
 847        int err;
 848        struct ipc_namespace *ns;
 849        DEFINE_WAKE_Q(wake_q);
 850
 851        ns = current->nsproxy->ipc_ns;
 852
 853        if (msgsz > ns->msg_ctlmax || (long) msgsz < 0 || msqid < 0)
 854                return -EINVAL;
 855        if (mtype < 1)
 856                return -EINVAL;
 857
 858        msg = load_msg(mtext, msgsz);
 859        if (IS_ERR(msg))
 860                return PTR_ERR(msg);
 861
 862        msg->m_type = mtype;
 863        msg->m_ts = msgsz;
 864
 865        rcu_read_lock();
 866        msq = msq_obtain_object_check(ns, msqid);
 867        if (IS_ERR(msq)) {
 868                err = PTR_ERR(msq);
 869                goto out_unlock1;
 870        }
 871
 872        ipc_lock_object(&msq->q_perm);
 873
 874        for (;;) {
 875                struct msg_sender s;
 876
 877                err = -EACCES;
 878                if (ipcperms(ns, &msq->q_perm, S_IWUGO))
 879                        goto out_unlock0;
 880
 881                /* raced with RMID? */
 882                if (!ipc_valid_object(&msq->q_perm)) {
 883                        err = -EIDRM;
 884                        goto out_unlock0;
 885                }
 886
 887                err = security_msg_queue_msgsnd(&msq->q_perm, msg, msgflg);
 888                if (err)
 889                        goto out_unlock0;
 890
 891                if (msg_fits_inqueue(msq, msgsz))
 892                        break;
 893
 894                /* queue full, wait: */
 895                if (msgflg & IPC_NOWAIT) {
 896                        err = -EAGAIN;
 897                        goto out_unlock0;
 898                }
 899
 900                /* enqueue the sender and prepare to block */
 901                ss_add(msq, &s, msgsz);
 902
 903                if (!ipc_rcu_getref(&msq->q_perm)) {
 904                        err = -EIDRM;
 905                        goto out_unlock0;
 906                }
 907
 908                ipc_unlock_object(&msq->q_perm);
 909                rcu_read_unlock();
 910                schedule();
 911
 912                rcu_read_lock();
 913                ipc_lock_object(&msq->q_perm);
 914
 915                ipc_rcu_putref(&msq->q_perm, msg_rcu_free);
 916                /* raced with RMID? */
 917                if (!ipc_valid_object(&msq->q_perm)) {
 918                        err = -EIDRM;
 919                        goto out_unlock0;
 920                }
 921                ss_del(&s);
 922
 923                if (signal_pending(current)) {
 924                        err = -ERESTARTNOHAND;
 925                        goto out_unlock0;
 926                }
 927
 928        }
 929
 930        ipc_update_pid(&msq->q_lspid, task_tgid(current));
 931        msq->q_stime = ktime_get_real_seconds();
 932
 933        if (!pipelined_send(msq, msg, &wake_q)) {
 934                /* no one is waiting for this message, enqueue it */
 935                list_add_tail(&msg->m_list, &msq->q_messages);
 936                msq->q_cbytes += msgsz;
 937                msq->q_qnum++;
 938                atomic_add(msgsz, &ns->msg_bytes);
 939                atomic_inc(&ns->msg_hdrs);
 940        }
 941
 942        err = 0;
 943        msg = NULL;
 944
 945out_unlock0:
 946        ipc_unlock_object(&msq->q_perm);
 947        wake_up_q(&wake_q);
 948out_unlock1:
 949        rcu_read_unlock();
 950        if (msg != NULL)
 951                free_msg(msg);
 952        return err;
 953}
 954
 955long ksys_msgsnd(int msqid, struct msgbuf __user *msgp, size_t msgsz,
 956                 int msgflg)
 957{
 958        long mtype;
 959
 960        if (get_user(mtype, &msgp->mtype))
 961                return -EFAULT;
 962        return do_msgsnd(msqid, mtype, msgp->mtext, msgsz, msgflg);
 963}
 964
 965SYSCALL_DEFINE4(msgsnd, int, msqid, struct msgbuf __user *, msgp, size_t, msgsz,
 966                int, msgflg)
 967{
 968        return ksys_msgsnd(msqid, msgp, msgsz, msgflg);
 969}
 970
 971#ifdef CONFIG_COMPAT
 972
 973struct compat_msgbuf {
 974        compat_long_t mtype;
 975        char mtext[1];
 976};
 977
 978long compat_ksys_msgsnd(int msqid, compat_uptr_t msgp,
 979                       compat_ssize_t msgsz, int msgflg)
 980{
 981        struct compat_msgbuf __user *up = compat_ptr(msgp);
 982        compat_long_t mtype;
 983
 984        if (get_user(mtype, &up->mtype))
 985                return -EFAULT;
 986        return do_msgsnd(msqid, mtype, up->mtext, (ssize_t)msgsz, msgflg);
 987}
 988
 989COMPAT_SYSCALL_DEFINE4(msgsnd, int, msqid, compat_uptr_t, msgp,
 990                       compat_ssize_t, msgsz, int, msgflg)
 991{
 992        return compat_ksys_msgsnd(msqid, msgp, msgsz, msgflg);
 993}
 994#endif
 995
 996static inline int convert_mode(long *msgtyp, int msgflg)
 997{
 998        if (msgflg & MSG_COPY)
 999                return SEARCH_NUMBER;
1000        /*
1001         *  find message of correct type.
1002         *  msgtyp = 0 => get first.
1003         *  msgtyp > 0 => get first message of matching type.
1004         *  msgtyp < 0 => get message with least type must be < abs(msgtype).
1005         */
1006        if (*msgtyp == 0)
1007                return SEARCH_ANY;
1008        if (*msgtyp < 0) {
1009                if (*msgtyp == LONG_MIN) /* -LONG_MIN is undefined */
1010                        *msgtyp = LONG_MAX;
1011                else
1012                        *msgtyp = -*msgtyp;
1013                return SEARCH_LESSEQUAL;
1014        }
1015        if (msgflg & MSG_EXCEPT)
1016                return SEARCH_NOTEQUAL;
1017        return SEARCH_EQUAL;
1018}
1019
1020static long do_msg_fill(void __user *dest, struct msg_msg *msg, size_t bufsz)
1021{
1022        struct msgbuf __user *msgp = dest;
1023        size_t msgsz;
1024
1025        if (put_user(msg->m_type, &msgp->mtype))
1026                return -EFAULT;
1027
1028        msgsz = (bufsz > msg->m_ts) ? msg->m_ts : bufsz;
1029        if (store_msg(msgp->mtext, msg, msgsz))
1030                return -EFAULT;
1031        return msgsz;
1032}
1033
1034#ifdef CONFIG_CHECKPOINT_RESTORE
1035/*
1036 * This function creates new kernel message structure, large enough to store
1037 * bufsz message bytes.
1038 */
1039static inline struct msg_msg *prepare_copy(void __user *buf, size_t bufsz)
1040{
1041        struct msg_msg *copy;
1042
1043        /*
1044         * Create dummy message to copy real message to.
1045         */
1046        copy = load_msg(buf, bufsz);
1047        if (!IS_ERR(copy))
1048                copy->m_ts = bufsz;
1049        return copy;
1050}
1051
1052static inline void free_copy(struct msg_msg *copy)
1053{
1054        if (copy)
1055                free_msg(copy);
1056}
1057#else
1058static inline struct msg_msg *prepare_copy(void __user *buf, size_t bufsz)
1059{
1060        return ERR_PTR(-ENOSYS);
1061}
1062
1063static inline void free_copy(struct msg_msg *copy)
1064{
1065}
1066#endif
1067
1068static struct msg_msg *find_msg(struct msg_queue *msq, long *msgtyp, int mode)
1069{
1070        struct msg_msg *msg, *found = NULL;
1071        long count = 0;
1072
1073        list_for_each_entry(msg, &msq->q_messages, m_list) {
1074                if (testmsg(msg, *msgtyp, mode) &&
1075                    !security_msg_queue_msgrcv(&msq->q_perm, msg, current,
1076                                               *msgtyp, mode)) {
1077                        if (mode == SEARCH_LESSEQUAL && msg->m_type != 1) {
1078                                *msgtyp = msg->m_type - 1;
1079                                found = msg;
1080                        } else if (mode == SEARCH_NUMBER) {
1081                                if (*msgtyp == count)
1082                                        return msg;
1083                        } else
1084                                return msg;
1085                        count++;
1086                }
1087        }
1088
1089        return found ?: ERR_PTR(-EAGAIN);
1090}
1091
1092static long do_msgrcv(int msqid, void __user *buf, size_t bufsz, long msgtyp, int msgflg,
1093               long (*msg_handler)(void __user *, struct msg_msg *, size_t))
1094{
1095        int mode;
1096        struct msg_queue *msq;
1097        struct ipc_namespace *ns;
1098        struct msg_msg *msg, *copy = NULL;
1099        DEFINE_WAKE_Q(wake_q);
1100
1101        ns = current->nsproxy->ipc_ns;
1102
1103        if (msqid < 0 || (long) bufsz < 0)
1104                return -EINVAL;
1105
1106        if (msgflg & MSG_COPY) {
1107                if ((msgflg & MSG_EXCEPT) || !(msgflg & IPC_NOWAIT))
1108                        return -EINVAL;
1109                copy = prepare_copy(buf, min_t(size_t, bufsz, ns->msg_ctlmax));
1110                if (IS_ERR(copy))
1111                        return PTR_ERR(copy);
1112        }
1113        mode = convert_mode(&msgtyp, msgflg);
1114
1115        rcu_read_lock();
1116        msq = msq_obtain_object_check(ns, msqid);
1117        if (IS_ERR(msq)) {
1118                rcu_read_unlock();
1119                free_copy(copy);
1120                return PTR_ERR(msq);
1121        }
1122
1123        for (;;) {
1124                struct msg_receiver msr_d;
1125
1126                msg = ERR_PTR(-EACCES);
1127                if (ipcperms(ns, &msq->q_perm, S_IRUGO))
1128                        goto out_unlock1;
1129
1130                ipc_lock_object(&msq->q_perm);
1131
1132                /* raced with RMID? */
1133                if (!ipc_valid_object(&msq->q_perm)) {
1134                        msg = ERR_PTR(-EIDRM);
1135                        goto out_unlock0;
1136                }
1137
1138                msg = find_msg(msq, &msgtyp, mode);
1139                if (!IS_ERR(msg)) {
1140                        /*
1141                         * Found a suitable message.
1142                         * Unlink it from the queue.
1143                         */
1144                        if ((bufsz < msg->m_ts) && !(msgflg & MSG_NOERROR)) {
1145                                msg = ERR_PTR(-E2BIG);
1146                                goto out_unlock0;
1147                        }
1148                        /*
1149                         * If we are copying, then do not unlink message and do
1150                         * not update queue parameters.
1151                         */
1152                        if (msgflg & MSG_COPY) {
1153                                msg = copy_msg(msg, copy);
1154                                goto out_unlock0;
1155                        }
1156
1157                        list_del(&msg->m_list);
1158                        msq->q_qnum--;
1159                        msq->q_rtime = ktime_get_real_seconds();
1160                        ipc_update_pid(&msq->q_lrpid, task_tgid(current));
1161                        msq->q_cbytes -= msg->m_ts;
1162                        atomic_sub(msg->m_ts, &ns->msg_bytes);
1163                        atomic_dec(&ns->msg_hdrs);
1164                        ss_wakeup(msq, &wake_q, false);
1165
1166                        goto out_unlock0;
1167                }
1168
1169                /* No message waiting. Wait for a message */
1170                if (msgflg & IPC_NOWAIT) {
1171                        msg = ERR_PTR(-ENOMSG);
1172                        goto out_unlock0;
1173                }
1174
1175                list_add_tail(&msr_d.r_list, &msq->q_receivers);
1176                msr_d.r_tsk = current;
1177                msr_d.r_msgtype = msgtyp;
1178                msr_d.r_mode = mode;
1179                if (msgflg & MSG_NOERROR)
1180                        msr_d.r_maxsize = INT_MAX;
1181                else
1182                        msr_d.r_maxsize = bufsz;
1183
1184                /* memory barrier not require due to ipc_lock_object() */
1185                WRITE_ONCE(msr_d.r_msg, ERR_PTR(-EAGAIN));
1186
1187                /* memory barrier not required, we own ipc_lock_object() */
1188                __set_current_state(TASK_INTERRUPTIBLE);
1189
1190                ipc_unlock_object(&msq->q_perm);
1191                rcu_read_unlock();
1192                schedule();
1193
1194                /*
1195                 * Lockless receive, part 1:
1196                 * We don't hold a reference to the queue and getting a
1197                 * reference would defeat the idea of a lockless operation,
1198                 * thus the code relies on rcu to guarantee the existence of
1199                 * msq:
1200                 * Prior to destruction, expunge_all(-EIRDM) changes r_msg.
1201                 * Thus if r_msg is -EAGAIN, then the queue not yet destroyed.
1202                 */
1203                rcu_read_lock();
1204
1205                /*
1206                 * Lockless receive, part 2:
1207                 * The work in pipelined_send() and expunge_all():
1208                 * - Set pointer to message
1209                 * - Queue the receiver task for later wakeup
1210                 * - Wake up the process after the lock is dropped.
1211                 *
1212                 * Should the process wake up before this wakeup (due to a
1213                 * signal) it will either see the message and continue ...
1214                 */
1215                msg = READ_ONCE(msr_d.r_msg);
1216                if (msg != ERR_PTR(-EAGAIN)) {
1217                        /* see MSG_BARRIER for purpose/pairing */
1218                        smp_acquire__after_ctrl_dep();
1219
1220                        goto out_unlock1;
1221                }
1222
1223                 /*
1224                  * ... or see -EAGAIN, acquire the lock to check the message
1225                  * again.
1226                  */
1227                ipc_lock_object(&msq->q_perm);
1228
1229                msg = READ_ONCE(msr_d.r_msg);
1230                if (msg != ERR_PTR(-EAGAIN))
1231                        goto out_unlock0;
1232
1233                list_del(&msr_d.r_list);
1234                if (signal_pending(current)) {
1235                        msg = ERR_PTR(-ERESTARTNOHAND);
1236                        goto out_unlock0;
1237                }
1238
1239                ipc_unlock_object(&msq->q_perm);
1240        }
1241
1242out_unlock0:
1243        ipc_unlock_object(&msq->q_perm);
1244        wake_up_q(&wake_q);
1245out_unlock1:
1246        rcu_read_unlock();
1247        if (IS_ERR(msg)) {
1248                free_copy(copy);
1249                return PTR_ERR(msg);
1250        }
1251
1252        bufsz = msg_handler(buf, msg, bufsz);
1253        free_msg(msg);
1254
1255        return bufsz;
1256}
1257
1258long ksys_msgrcv(int msqid, struct msgbuf __user *msgp, size_t msgsz,
1259                 long msgtyp, int msgflg)
1260{
1261        return do_msgrcv(msqid, msgp, msgsz, msgtyp, msgflg, do_msg_fill);
1262}
1263
1264SYSCALL_DEFINE5(msgrcv, int, msqid, struct msgbuf __user *, msgp, size_t, msgsz,
1265                long, msgtyp, int, msgflg)
1266{
1267        return ksys_msgrcv(msqid, msgp, msgsz, msgtyp, msgflg);
1268}
1269
1270#ifdef CONFIG_COMPAT
1271static long compat_do_msg_fill(void __user *dest, struct msg_msg *msg, size_t bufsz)
1272{
1273        struct compat_msgbuf __user *msgp = dest;
1274        size_t msgsz;
1275
1276        if (put_user(msg->m_type, &msgp->mtype))
1277                return -EFAULT;
1278
1279        msgsz = (bufsz > msg->m_ts) ? msg->m_ts : bufsz;
1280        if (store_msg(msgp->mtext, msg, msgsz))
1281                return -EFAULT;
1282        return msgsz;
1283}
1284
1285long compat_ksys_msgrcv(int msqid, compat_uptr_t msgp, compat_ssize_t msgsz,
1286                        compat_long_t msgtyp, int msgflg)
1287{
1288        return do_msgrcv(msqid, compat_ptr(msgp), (ssize_t)msgsz, (long)msgtyp,
1289                         msgflg, compat_do_msg_fill);
1290}
1291
1292COMPAT_SYSCALL_DEFINE5(msgrcv, int, msqid, compat_uptr_t, msgp,
1293                       compat_ssize_t, msgsz, compat_long_t, msgtyp,
1294                       int, msgflg)
1295{
1296        return compat_ksys_msgrcv(msqid, msgp, msgsz, msgtyp, msgflg);
1297}
1298#endif
1299
1300void msg_init_ns(struct ipc_namespace *ns)
1301{
1302        ns->msg_ctlmax = MSGMAX;
1303        ns->msg_ctlmnb = MSGMNB;
1304        ns->msg_ctlmni = MSGMNI;
1305
1306        atomic_set(&ns->msg_bytes, 0);
1307        atomic_set(&ns->msg_hdrs, 0);
1308        ipc_init_ids(&ns->ids[IPC_MSG_IDS]);
1309}
1310
1311#ifdef CONFIG_IPC_NS
1312void msg_exit_ns(struct ipc_namespace *ns)
1313{
1314        free_ipcs(ns, &msg_ids(ns), freeque);
1315        idr_destroy(&ns->ids[IPC_MSG_IDS].ipcs_idr);
1316        rhashtable_destroy(&ns->ids[IPC_MSG_IDS].key_ht);
1317}
1318#endif
1319
1320#ifdef CONFIG_PROC_FS
1321static int sysvipc_msg_proc_show(struct seq_file *s, void *it)
1322{
1323        struct pid_namespace *pid_ns = ipc_seq_pid_ns(s);
1324        struct user_namespace *user_ns = seq_user_ns(s);
1325        struct kern_ipc_perm *ipcp = it;
1326        struct msg_queue *msq = container_of(ipcp, struct msg_queue, q_perm);
1327
1328        seq_printf(s,
1329                   "%10d %10d  %4o  %10lu %10lu %5u %5u %5u %5u %5u %5u %10llu %10llu %10llu\n",
1330                   msq->q_perm.key,
1331                   msq->q_perm.id,
1332                   msq->q_perm.mode,
1333                   msq->q_cbytes,
1334                   msq->q_qnum,
1335                   pid_nr_ns(msq->q_lspid, pid_ns),
1336                   pid_nr_ns(msq->q_lrpid, pid_ns),
1337                   from_kuid_munged(user_ns, msq->q_perm.uid),
1338                   from_kgid_munged(user_ns, msq->q_perm.gid),
1339                   from_kuid_munged(user_ns, msq->q_perm.cuid),
1340                   from_kgid_munged(user_ns, msq->q_perm.cgid),
1341                   msq->q_stime,
1342                   msq->q_rtime,
1343                   msq->q_ctime);
1344
1345        return 0;
1346}
1347#endif
1348
1349void __init msg_init(void)
1350{
1351        msg_init_ns(&init_ipc_ns);
1352
1353        ipc_init_proc_interface("sysvipc/msg",
1354                                "       key      msqid perms      cbytes       qnum lspid lrpid   uid   gid  cuid  cgid      stime      rtime      ctime\n",
1355                                IPC_MSG_IDS, sysvipc_msg_proc_show);
1356}
1357