]> git.saurik.com Git - apple/xnu.git/blobdiff - bsd/kern/sysv_sem.c
xnu-1228.0.2.tar.gz
[apple/xnu.git] / bsd / kern / sysv_sem.c
index 5691a71a9c8603cd409dfdeabc42995e0acbbc5f..d244876ab88de0950eee862cce3d07314b99828a 100644 (file)
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2000-2007 Apple Inc. All rights reserved.
  *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
  * 
 /*
  * John Bellardo modified the implementation for Darwin. 12/2000
  */
+/*
+ * NOTICE: This file was modified by McAfee Research in 2004 to introduce
+ * support for mandatory and extensible security protections.  This notice
+ * is included in support of clause 2.2 (b) of the Apple Public License,
+ * Version 2.0.
+ * Copyright (c) 2005-2006 SPARTA, Inc.
+ */
 
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/ipcs.h>
 #include <sys/sysent.h>
 #include <sys/sysproto.h>
+#if CONFIG_MACF
+#include <security/mac_framework.h>
+#endif
 
 #include <bsm/audit_kernel.h>
 
+#if SYSV_SEM
+
 
 /* Uncomment this line to see the debugging output */
 /* #define SEM_DEBUG */
 
+/* Uncomment this line to see MAC debugging output. */
+/* #define     MAC_DEBUG */
+#if CONFIG_MACF_DEBUG
+#define        MPRINTF(a)      printf(a)
+#else
+#define        MPRINTF(a)
+#endif
+
 #define M_SYSVSEM      M_TEMP
 
 
@@ -95,8 +115,8 @@ struct seminfo seminfo = {
 };
 
 
-static struct sem_undo *semu_alloc(struct proc *p);
-static int semundo_adjust(struct proc *p, struct sem_undo **supptr
+static int semu_alloc(struct proc *p);
+static int semundo_adjust(struct proc *p, int *supidx
                int semid, int semnum, int adjval);
 static void semundo_clear(int semid, int semnum);
 
@@ -107,9 +127,9 @@ static sy_call_t *semcalls[] = {
 };
 
 static int             semtot = 0;             /* # of used semaphores */
-struct user_semid_ds   *sema = NULL;           /* semaphore id pool */
+struct semid_kernel    *sema = NULL;           /* semaphore id pool */
 struct sem             *sem_pool =  NULL;      /* semaphore pool */
-static struct sem_undo *semu_list = NULL;      /* active undo structures */
+static int             semu_list_idx = -1;     /* active undo structures */
 struct sem_undo                *semu = NULL;           /* semaphore undo pool */
 
 
@@ -128,12 +148,10 @@ sysv_sem_lock_init( void )
 {
 
     sysv_sem_subsys_lck_grp_attr = lck_grp_attr_alloc_init();
-    lck_grp_attr_setstat(sysv_sem_subsys_lck_grp_attr);
 
-    sysv_sem_subsys_lck_grp = lck_grp_alloc_init("sysv_shm_subsys_lock", sysv_sem_subsys_lck_grp_attr);
+    sysv_sem_subsys_lck_grp = lck_grp_alloc_init("sysv_sem_subsys_lock", sysv_sem_subsys_lck_grp_attr);
 
     sysv_sem_subsys_lck_attr = lck_attr_alloc_init();
-    lck_attr_setdebug(sysv_sem_subsys_lck_attr); 
     lck_mtx_init(&sysv_sem_subsys_mutex, sysv_sem_subsys_lck_grp, sysv_sem_subsys_lck_attr);
 }
 
@@ -273,7 +291,7 @@ grow_semu_array(int newSize)
 static int
 grow_sema_array(int newSize)
 {
-       register struct user_semid_ds *newSema;
+       register struct semid_kernel *newSema;
        register int i;
 
        if (newSize <= seminfo.semmni)
@@ -292,8 +310,8 @@ grow_sema_array(int newSize)
 #ifdef SEM_DEBUG
        printf("growing sema[] from %d to %d\n", seminfo.semmni, newSize);
 #endif
-       MALLOC(newSema, struct user_semid_ds *,
-              sizeof (struct user_semid_ds) * newSize,
+       MALLOC(newSema, struct semid_kernel *,
+              sizeof (struct semid_kernel) * newSize,
               M_SYSVSEM, M_WAITOK | M_ZERO);
        if (NULL == newSema)
        {
@@ -313,11 +331,19 @@ grow_sema_array(int newSize)
                 * this with the existing code, so we wake up the
                 * process and let it do a lot of work to determine the
                 * semaphore set is really not available yet, and then
-                * sleep on the correct, reallocated user_semid_ds pointer.
+                * sleep on the correct, reallocated semid_kernel pointer.
                 */
-               if (sema[i].sem_perm.mode & SEM_ALLOC)
+               if (sema[i].u.sem_perm.mode & SEM_ALLOC)
                        wakeup((caddr_t)&sema[i]);
        }
+
+#if CONFIG_MACF
+       for (i = seminfo.semmni; i < newSize; i++)
+       {
+               mac_sysvsem_label_init(&newSema[i]);
+       }
+#endif
+       
        /*
         * The new elements (from newSema[i] to newSema[newSize-1]) have their
         * "sem_base" and "sem_perm.mode" set to 0 (i.e. NULL) by the M_ZERO
@@ -382,8 +408,8 @@ grow_sem_pool(int new_pool_size)
 
        /* Update our id structures to point to the new semaphores */
        for(i = 0; i < seminfo.semmni; i++) {
-               if (sema[i].sem_perm.mode & SEM_ALLOC)  /* ID in use */
-                       sema[i].sem_base += (new_sem_pool - sem_pool);
+               if (sema[i].u.sem_perm.mode & SEM_ALLOC)  /* ID in use */
+                       sema[i].u.sem_base += (new_sem_pool - sem_pool);
        }
 
        sem_free = sem_pool;
@@ -407,12 +433,12 @@ grow_sem_pool(int new_pool_size)
  * Assumes we already hold the subsystem lock.
  */
 
-static struct sem_undo *
+static int
 semu_alloc(struct proc *p)
 {
        register int i;
        register struct sem_undo *suptr;
-       register struct sem_undo **supptr;
+       int *supidx;
        int attempt;
 
        /*
@@ -430,12 +456,12 @@ semu_alloc(struct proc *p)
                for (i = 0; i < seminfo.semmnu; i++) {
                        suptr = SEMU(i);
                        if (suptr->un_proc == NULL) {
-                               suptr->un_next = semu_list;
-                               semu_list = suptr;
+                               suptr->un_next_idx = semu_list_idx;
+                               semu_list_idx = i;
                                suptr->un_cnt = 0;
                                suptr->un_ent = NULL;
                                suptr->un_proc = p;
-                               return(suptr);
+                               return i;
                        }
                }
 
@@ -448,14 +474,15 @@ semu_alloc(struct proc *p)
                        /* All the structures are in use - try to free some */
                        int did_something = 0;
 
-                       supptr = &semu_list;
-                       while ((suptr = *supptr) != NULL) {
+                       supidx = &semu_list_idx;
+                       while (*supidx != -1) {
+                               suptr = SEMU(*supidx);
                                if (suptr->un_cnt == 0)  {
                                        suptr->un_proc = NULL;
-                                       *supptr = suptr->un_next;
+                                       *supidx = suptr->un_next_idx;
                                        did_something = 1;
                                } else
-                                       supptr = &(suptr->un_next);
+                                       supidx = &(suptr->un_next_idx);
                        }
 
                        /* If we didn't free anything. Try expanding
@@ -465,7 +492,7 @@ semu_alloc(struct proc *p)
                         */
                        if (!did_something)
                                if (!grow_semu_array(seminfo.semmnu + 1))
-                                       return(NULL);
+                                       return -1;
                } else {
                        /*
                         * The second pass failed even though we freed
@@ -475,7 +502,7 @@ semu_alloc(struct proc *p)
                        panic("semu_alloc - second attempt failed");
                }
        }
-       return (NULL);
+       return -1;
 }
 
 /*
@@ -484,10 +511,11 @@ semu_alloc(struct proc *p)
  * Assumes we already hold the subsystem lock.
  */
 static int
-semundo_adjust(struct proc *p, struct sem_undo **supptr, int semid,
+semundo_adjust(struct proc *p, int *supidx, int semid,
        int semnum, int adjval)
 {
        register struct sem_undo *suptr;
+       int suidx;
        register struct undo *sueptr, **suepptr, *new_sueptr;
        int i;
 
@@ -495,22 +523,23 @@ semundo_adjust(struct proc *p, struct sem_undo **supptr, int semid,
         * Look for and remember the sem_undo if the caller doesn't provide it
         */
 
-       suptr = *supptr;
-       if (suptr == NULL) {
-               for (suptr = semu_list; suptr != NULL;
-                   suptr = suptr->un_next) {
+       suidx = *supidx;
+       if (suidx == -1) {
+               for (suidx = semu_list_idx; suidx != -1;
+                   suidx = suptr->un_next_idx) {
+                       suptr = SEMU(suidx);
                        if (suptr->un_proc == p) {
-                               *supptr = suptr;
+                               *supidx = suidx;
                                break;
                        }
                }
-               if (suptr == NULL) {
+               if (suidx == -1) {
                        if (adjval == 0)
                                return(0);
-                       suptr = semu_alloc(p);
-                       if (suptr == NULL)
+                       suidx = semu_alloc(p);
+                       if (suidx == -1)
                                return(ENOSPC);
-                       *supptr = suptr;
+                       *supidx = suidx;
                }
        }
 
@@ -518,6 +547,7 @@ semundo_adjust(struct proc *p, struct sem_undo **supptr, int semid,
         * Look for the requested entry and adjust it (delete if adjval becomes
         * 0).
         */
+       suptr = SEMU(suidx);
        new_sueptr = NULL;
        for (i = 0, suepptr = &suptr->un_ent, sueptr = suptr->un_ent;
             i < suptr->un_cnt;
@@ -572,12 +602,14 @@ static void
 semundo_clear(int semid, int semnum)
 {
        struct sem_undo *suptr;
+       int suidx;
 
-       for (suptr = semu_list; suptr != NULL; suptr = suptr->un_next) {
+       for (suidx = semu_list_idx; suidx != -1; suidx = suptr->un_next_idx) {
                struct undo *sueptr;
                struct undo **suepptr;
                int i = 0;
 
+               suptr = SEMU(suidx);
                sueptr = suptr->un_ent;
                suepptr = &suptr->un_ent;
                while (i < suptr->un_cnt) {
@@ -616,7 +648,7 @@ semctl(struct proc *p, struct semctl_args *uap, register_t *retval)
        kauth_cred_t cred = kauth_cred_get();
        int i, rval, eval;
        struct user_semid_ds sbuf;
-       struct user_semid_ds *semaptr;
+       struct semid_kernel *semakptr;
        struct user_semid_ds uds;
        
 
@@ -639,38 +671,46 @@ semctl(struct proc *p, struct semctl_args *uap, register_t *retval)
                goto semctlout;
        }
 
-       semaptr = &sema[semid];
-       if ((semaptr->sem_perm.mode & SEM_ALLOC) == 0 ||
-           semaptr->sem_perm.seq != IPCID_TO_SEQ(uap->semid)) {
+       semakptr = &sema[semid];
+       if ((semakptr->u.sem_perm.mode & SEM_ALLOC) == 0 ||
+           semakptr->u.sem_perm._seq != IPCID_TO_SEQ(uap->semid)) {
                eval = EINVAL;
                goto semctlout;
        }
+#if CONFIG_MACF
+       eval = mac_sysvsem_check_semctl(cred, semakptr, cmd);
+       if (eval)
+               goto semctlout;
+#endif
 
        eval = 0;
        rval = 0;
 
        switch (cmd) {
        case IPC_RMID:
-               if ((eval = ipcperm(cred, &semaptr->sem_perm, IPC_M))) 
+               if ((eval = ipcperm(cred, &semakptr->u.sem_perm, IPC_M))) 
                        goto semctlout;
 
-               semaptr->sem_perm.cuid = kauth_cred_getuid(cred);
-               semaptr->sem_perm.uid = kauth_cred_getuid(cred);
-               semtot -= semaptr->sem_nsems;
-               for (i = semaptr->sem_base - sem_pool; i < semtot; i++)
-                       sem_pool[i] = sem_pool[i + semaptr->sem_nsems];
+               semakptr->u.sem_perm.cuid = kauth_cred_getuid(cred);
+               semakptr->u.sem_perm.uid = kauth_cred_getuid(cred);
+               semtot -= semakptr->u.sem_nsems;
+               for (i = semakptr->u.sem_base - sem_pool; i < semtot; i++)
+                       sem_pool[i] = sem_pool[i + semakptr->u.sem_nsems];
                for (i = 0; i < seminfo.semmni; i++) {
-                       if ((sema[i].sem_perm.mode & SEM_ALLOC) &&
-                           sema[i].sem_base > semaptr->sem_base)
-                               sema[i].sem_base -= semaptr->sem_nsems;
+                       if ((sema[i].u.sem_perm.mode & SEM_ALLOC) &&
+                           sema[i].u.sem_base > semakptr->u.sem_base)
+                               sema[i].u.sem_base -= semakptr->u.sem_nsems;
                }
-               semaptr->sem_perm.mode = 0;
+               semakptr->u.sem_perm.mode = 0;
+#if CONFIG_MACF
+               mac_sysvsem_label_recycle(semakptr);
+#endif
                semundo_clear(semid, -1);
-               wakeup((caddr_t)semaptr);
+               wakeup((caddr_t)semakptr);
                break;
 
        case IPC_SET:
-               if ((eval = ipcperm(cred, &semaptr->sem_perm, IPC_M)))
+               if ((eval = ipcperm(cred, &semakptr->u.sem_perm, IPC_M)))
                                goto semctlout;
 
                if (IS_64BIT_PROCESS(p)) {
@@ -685,17 +725,17 @@ semctl(struct proc *p, struct semctl_args *uap, register_t *retval)
                        goto semctlout;
                }
 
-               semaptr->sem_perm.uid = sbuf.sem_perm.uid;
-               semaptr->sem_perm.gid = sbuf.sem_perm.gid;
-               semaptr->sem_perm.mode = (semaptr->sem_perm.mode & ~0777) |
-                   (sbuf.sem_perm.mode & 0777);
-               semaptr->sem_ctime = sysv_semtime();
+               semakptr->u.sem_perm.uid = sbuf.sem_perm.uid;
+               semakptr->u.sem_perm.gid = sbuf.sem_perm.gid;
+               semakptr->u.sem_perm.mode = (semakptr->u.sem_perm.mode &
+                   ~0777) | (sbuf.sem_perm.mode & 0777);
+               semakptr->u.sem_ctime = sysv_semtime();
                break;
 
        case IPC_STAT:
-               if ((eval = ipcperm(cred, &semaptr->sem_perm, IPC_R)))
+               if ((eval = ipcperm(cred, &semakptr->u.sem_perm, IPC_R)))
                                goto semctlout;
-               bcopy(semaptr, &uds, sizeof(struct user_semid_ds));
+               bcopy((caddr_t)&semakptr->u, &uds, sizeof(struct user_semid_ds));
                if (IS_64BIT_PROCESS(p)) {
                        eval = copyout(&uds, user_arg.buf, sizeof(struct user_semid_ds));
                } else {
@@ -706,42 +746,42 @@ semctl(struct proc *p, struct semctl_args *uap, register_t *retval)
                break;
 
        case GETNCNT:
-               if ((eval = ipcperm(cred, &semaptr->sem_perm, IPC_R)))
+               if ((eval = ipcperm(cred, &semakptr->u.sem_perm, IPC_R)))
                                goto semctlout;
-               if (semnum < 0 || semnum >= semaptr->sem_nsems) {
+               if (semnum < 0 || semnum >= semakptr->u.sem_nsems) {
                        eval = EINVAL;
                        goto semctlout;
                }
-               rval = semaptr->sem_base[semnum].semncnt;
+               rval = semakptr->u.sem_base[semnum].semncnt;
                break;
 
        case GETPID:
-               if ((eval = ipcperm(cred, &semaptr->sem_perm, IPC_R)))
+               if ((eval = ipcperm(cred, &semakptr->u.sem_perm, IPC_R)))
                                goto semctlout;
-               if (semnum < 0 || semnum >= semaptr->sem_nsems) {
+               if (semnum < 0 || semnum >= semakptr->u.sem_nsems) {
                        eval = EINVAL;
                        goto semctlout;
                }
-               rval = semaptr->sem_base[semnum].sempid;
+               rval = semakptr->u.sem_base[semnum].sempid;
                break;
 
        case GETVAL:
-               if ((eval = ipcperm(cred, &semaptr->sem_perm, IPC_R)))
+               if ((eval = ipcperm(cred, &semakptr->u.sem_perm, IPC_R)))
                                goto semctlout;
-               if (semnum < 0 || semnum >= semaptr->sem_nsems) {
+               if (semnum < 0 || semnum >= semakptr->u.sem_nsems) {
                        eval = EINVAL;
                        goto semctlout;
                }
-               rval = semaptr->sem_base[semnum].semval;
+               rval = semakptr->u.sem_base[semnum].semval;
                break;
 
        case GETALL:
-               if ((eval = ipcperm(cred, &semaptr->sem_perm, IPC_R)))
+               if ((eval = ipcperm(cred, &semakptr->u.sem_perm, IPC_R)))
                                goto semctlout;
 /* XXXXXXXXXXXXXXXX TBD XXXXXXXXXXXXXXXX */
-               for (i = 0; i < semaptr->sem_nsems; i++) {
+               for (i = 0; i < semakptr->u.sem_nsems; i++) {
                        /* XXX could be done in one go... */
-                       eval = copyout((caddr_t)&semaptr->sem_base[i].semval,
+                       eval = copyout((caddr_t)&semakptr->u.sem_base[i].semval,
                            user_arg.array + (i * sizeof(unsigned short)),
                            sizeof(unsigned short));
                        if (eval != 0)
@@ -750,24 +790,24 @@ semctl(struct proc *p, struct semctl_args *uap, register_t *retval)
                break;
 
        case GETZCNT:
-               if ((eval = ipcperm(cred, &semaptr->sem_perm, IPC_R)))
+               if ((eval = ipcperm(cred, &semakptr->u.sem_perm, IPC_R)))
                                goto semctlout;
-               if (semnum < 0 || semnum >= semaptr->sem_nsems) {
+               if (semnum < 0 || semnum >= semakptr->u.sem_nsems) {
                        eval = EINVAL;
                        goto semctlout;
                }
-               rval = semaptr->sem_base[semnum].semzcnt;
+               rval = semakptr->u.sem_base[semnum].semzcnt;
                break;
 
        case SETVAL:
-               if ((eval = ipcperm(cred, &semaptr->sem_perm, IPC_W)))
+               if ((eval = ipcperm(cred, &semakptr->u.sem_perm, IPC_W)))
                 {
 #ifdef SEM_DEBUG
                        printf("Invalid credentials for write\n");
 #endif
                                goto semctlout;
                }
-               if (semnum < 0 || semnum >= semaptr->sem_nsems)
+               if (semnum < 0 || semnum >= semakptr->u.sem_nsems)
                {
 #ifdef SEM_DEBUG
                        printf("Invalid number out of range for set\n");
@@ -780,25 +820,29 @@ semctl(struct proc *p, struct semctl_args *uap, register_t *retval)
                 * to avoid introducing endieness and a pad field into the
                 * header file.  Ugly, but it works.
                 */
-               semaptr->sem_base[semnum].semval = CAST_DOWN(int,user_arg.buf);
+               semakptr->u.sem_base[semnum].semval = CAST_DOWN(int,user_arg.buf);
+               semakptr->u.sem_base[semnum].sempid = p->p_pid;
+               /* XXX scottl Should there be a MAC call here? */
                semundo_clear(semid, semnum);
-               wakeup((caddr_t)semaptr);
+               wakeup((caddr_t)semakptr);
                break;
 
        case SETALL:
-               if ((eval = ipcperm(cred, &semaptr->sem_perm, IPC_W)))
+               if ((eval = ipcperm(cred, &semakptr->u.sem_perm, IPC_W)))
                                goto semctlout;
 /*** XXXXXXXXXXXX TBD ********/
-               for (i = 0; i < semaptr->sem_nsems; i++) {
+               for (i = 0; i < semakptr->u.sem_nsems; i++) {
                        /* XXX could be done in one go... */
                        eval = copyin(user_arg.array + (i * sizeof(unsigned short)),
-                           (caddr_t)&semaptr->sem_base[i].semval,
+                           (caddr_t)&semakptr->u.sem_base[i].semval,
                            sizeof(unsigned short));
                        if (eval != 0)
                                break;
+                       semakptr->u.sem_base[i].sempid = p->p_pid;
                }
+               /* XXX scottl Should there be a MAC call here? */
                semundo_clear(semid, -1);
-               wakeup((caddr_t)semaptr);
+               wakeup((caddr_t)semakptr);
                break;
 
        default:
@@ -835,18 +879,18 @@ semget(__unused struct proc *p, struct semget_args *uap, register_t *retval)
     
        if (key != IPC_PRIVATE) {
                for (semid = 0; semid < seminfo.semmni; semid++) {
-                       if ((sema[semid].sem_perm.mode & SEM_ALLOC) &&
-                           sema[semid].sem_perm.key == key)
+                       if ((sema[semid].u.sem_perm.mode & SEM_ALLOC) &&
+                           sema[semid].u.sem_perm._key == key)
                                break;
                }
                if (semid < seminfo.semmni) {
 #ifdef SEM_DEBUG
                        printf("found public key\n");
 #endif
-                       if ((eval = ipcperm(cred, &sema[semid].sem_perm,
+                       if ((eval = ipcperm(cred, &sema[semid].u.sem_perm,
                            semflg & 0700)))
                                goto semgetout;
-                       if (nsems < 0 || sema[semid].sem_nsems < nsems) {
+                       if (nsems < 0 || sema[semid].u.sem_nsems < nsems) {
 #ifdef SEM_DEBUG
                                printf("too small\n");
 #endif
@@ -860,6 +904,11 @@ semget(__unused struct proc *p, struct semget_args *uap, register_t *retval)
                                eval = EEXIST;
                                goto semgetout;
                        }
+#if CONFIG_MACF
+                       eval = mac_sysvsem_check_semget(cred, &sema[semid]);
+                       if (eval) 
+                               goto semgetout;
+#endif
                        goto found;
                }
        }
@@ -890,7 +939,7 @@ semget(__unused struct proc *p, struct semget_args *uap, register_t *retval)
                        }
                }
                for (semid = 0; semid < seminfo.semmni; semid++) {
-                       if ((sema[semid].sem_perm.mode & SEM_ALLOC) == 0)
+                       if ((sema[semid].u.sem_perm.mode & SEM_ALLOC) == 0)
                                break;
                }
                if (semid == seminfo.semmni) {
@@ -909,23 +958,26 @@ semget(__unused struct proc *p, struct semget_args *uap, register_t *retval)
 #ifdef SEM_DEBUG
                printf("semid %d is available\n", semid);
 #endif
-               sema[semid].sem_perm.key = key;
-               sema[semid].sem_perm.cuid = kauth_cred_getuid(cred);
-               sema[semid].sem_perm.uid = kauth_cred_getuid(cred);
-               sema[semid].sem_perm.cgid = cred->cr_gid;
-               sema[semid].sem_perm.gid = cred->cr_gid;
-               sema[semid].sem_perm.mode = (semflg & 0777) | SEM_ALLOC;
-               sema[semid].sem_perm.seq =
-                   (sema[semid].sem_perm.seq + 1) & 0x7fff;
-               sema[semid].sem_nsems = nsems;
-               sema[semid].sem_otime = 0;
-               sema[semid].sem_ctime = sysv_semtime();
-               sema[semid].sem_base = &sem_pool[semtot];
+               sema[semid].u.sem_perm._key = key;
+               sema[semid].u.sem_perm.cuid = kauth_cred_getuid(cred);
+               sema[semid].u.sem_perm.uid = kauth_cred_getuid(cred);
+               sema[semid].u.sem_perm.cgid = cred->cr_gid;
+               sema[semid].u.sem_perm.gid = cred->cr_gid;
+               sema[semid].u.sem_perm.mode = (semflg & 0777) | SEM_ALLOC;
+               sema[semid].u.sem_perm._seq =
+                   (sema[semid].u.sem_perm._seq + 1) & 0x7fff;
+               sema[semid].u.sem_nsems = nsems;
+               sema[semid].u.sem_otime = 0;
+               sema[semid].u.sem_ctime = sysv_semtime();
+               sema[semid].u.sem_base = &sem_pool[semtot];
                semtot += nsems;
-               bzero(sema[semid].sem_base,
-                   sizeof(sema[semid].sem_base[0])*nsems);
+               bzero(sema[semid].u.sem_base,
+                   sizeof(sema[semid].u.sem_base[0])*nsems);
+#if CONFIG_MACF
+               mac_sysvsem_label_associate(cred, &sema[semid]);
+#endif
 #ifdef SEM_DEBUG
-               printf("sembase = 0x%x, next = 0x%x\n", sema[semid].sem_base,
+               printf("sembase = 0x%x, next = 0x%x\n", sema[semid].u.sem_base,
                    &sem_pool[semtot]);
 #endif
        } else {
@@ -937,7 +989,7 @@ semget(__unused struct proc *p, struct semget_args *uap, register_t *retval)
        }
 
 found:
-       *retval = IXSEQ_TO_IPCID(semid, sema[semid].sem_perm);
+       *retval = IXSEQ_TO_IPCID(semid, sema[semid].u.sem_perm);
        AUDIT_ARG(svipc_id, *retval);
 #ifdef SEM_DEBUG
        printf("semget is done, returning %d\n", *retval);
@@ -955,10 +1007,10 @@ semop(struct proc *p, struct semop_args *uap, register_t *retval)
        int semid = uap->semid;
        int nsops = uap->nsops;
        struct sembuf sops[MAX_SOPS];
-       register struct user_semid_ds *semaptr;
+       register struct semid_kernel *semakptr;
        register struct sembuf *sopptr = NULL;  /* protected by 'semptr' */
        register struct sem *semptr = NULL;     /* protected by 'if' */
-       struct sem_undo *suptr = NULL;
+       int supidx = -1;
        int i, j, eval;
        int do_wakeup, do_undos;
 
@@ -977,23 +1029,41 @@ semop(struct proc *p, struct semop_args *uap, register_t *retval)
                goto semopout;
        }
 
-       semaptr = &sema[semid];
-       if ((semaptr->sem_perm.mode & SEM_ALLOC) == 0) {
+       semakptr = &sema[semid];
+       if ((semakptr->u.sem_perm.mode & SEM_ALLOC) == 0) {
                eval = EINVAL;
                goto semopout;
        }
-       if (semaptr->sem_perm.seq != IPCID_TO_SEQ(uap->semid)) {
+       if (semakptr->u.sem_perm._seq != IPCID_TO_SEQ(uap->semid)) {
                eval = EINVAL;
                goto semopout;
        }
 
-       if ((eval = ipcperm(kauth_cred_get(), &semaptr->sem_perm, IPC_W))) {
+       if ((eval = ipcperm(kauth_cred_get(), &semakptr->u.sem_perm, IPC_W))) {
 #ifdef SEM_DEBUG
                printf("eval = %d from ipaccess\n", eval);
 #endif
                goto semopout;
        }
 
+#if CONFIG_MACF
+       /*
+        * Initial pass thru sops to see what permissions are needed.
+        */
+       j = 0;          /* permission needed */
+       for (i = 0; i < nsops; i++)
+               j |= (sops[i].sem_op == 0) ? SEM_R : SEM_A;
+
+       /*
+        * The MAC hook checks whether the thread has read (and possibly
+        * write) permissions to the semaphore array based on the
+        * sopptr->sem_op value.
+        */
+       eval = mac_sysvsem_check_semop(kauth_cred_get(), semakptr, j);
+       if (eval)
+               goto semopout;
+#endif
+
        if (nsops < 0 || nsops > MAX_SOPS) {
 #ifdef SEM_DEBUG
                printf("too many sops (max=%d, nsops=%d)\n", MAX_SOPS, nsops);
@@ -1028,16 +1098,16 @@ semop(struct proc *p, struct semop_args *uap, register_t *retval)
                for (i = 0; i < nsops; i++) {
                        sopptr = &sops[i];
 
-                       if (sopptr->sem_num >= semaptr->sem_nsems) {
+                       if (sopptr->sem_num >= semakptr->u.sem_nsems) {
                                eval = EFBIG;
                                goto semopout;
                        }
 
-                       semptr = &semaptr->sem_base[sopptr->sem_num];
+                       semptr = &semakptr->u.sem_base[sopptr->sem_num];
 
 #ifdef SEM_DEBUG
-                       printf("semop:  semaptr=%x, sem_base=%x, semptr=%x, sem[%d]=%d : op=%d, flag=%s\n",
-                           semaptr, semaptr->sem_base, semptr,
+                       printf("semop:  semakptr=%x, sem_base=%x, semptr=%x, sem[%d]=%d : op=%d, flag=%s\n",
+                           semakptr, semakptr->u.sem_base, semptr,
                            sopptr->sem_num, semptr->semval, sopptr->sem_op,
                            (sopptr->sem_flg & IPC_NOWAIT) ? "nowait" : "wait");
 #endif
@@ -1085,7 +1155,7 @@ semop(struct proc *p, struct semop_args *uap, register_t *retval)
                printf("semop:  rollback 0 through %d\n", i-1);
 #endif
                for (j = 0; j < i; j++)
-                       semaptr->sem_base[sops[j].sem_num].semval -=
+                       semakptr->u.sem_base[sops[j].sem_num].semval -=
                            sops[j].sem_op;
 
                /*
@@ -1110,7 +1180,7 @@ semop(struct proc *p, struct semop_args *uap, register_t *retval)
                 * waiting for. We will get the lock back after we
                 * wake up.
                 */
-               eval = msleep((caddr_t)semaptr, &sysv_sem_subsys_mutex , (PZERO - 4) | PCATCH,
+               eval = msleep((caddr_t)semakptr, &sysv_sem_subsys_mutex , (PZERO - 4) | PCATCH,
                    "semwait", 0);
                 
 #ifdef SEM_DEBUG
@@ -1127,15 +1197,20 @@ semop(struct proc *p, struct semop_args *uap, register_t *retval)
                 * structures and re-validate them.
                 */
 
-               suptr = NULL;   /* sem_undo may have been reallocated */
-               semaptr = &sema[semid];    /* sema may have been reallocated */
+               semptr = NULL;
 
                /*
                 * Make sure that the semaphore still exists
+                *
+                * XXX POSIX: Third test this 'if' and 'EINTR' precedence may
+                * fail testing; if so, we will need to revert this code.
                 */
-               if ((semaptr->sem_perm.mode & SEM_ALLOC) == 0 ||
-                   semaptr->sem_perm.seq != IPCID_TO_SEQ(uap->semid) ||
-                   sopptr->sem_num >= semaptr->sem_nsems) {
+               semakptr = &sema[semid];   /* sema may have been reallocated */
+               if ((semakptr->u.sem_perm.mode & SEM_ALLOC) == 0 ||
+                   semakptr->u.sem_perm._seq != IPCID_TO_SEQ(uap->semid) ||
+                   sopptr->sem_num >= semakptr->u.sem_nsems) {
+                       /* The man page says to return EIDRM. */
+                       /* Unfortunately, BSD doesn't define that code! */
                        if (eval == EINTR) {
                                /*
                                 * EINTR takes precedence over the fact that
@@ -1143,14 +1218,10 @@ semop(struct proc *p, struct semop_args *uap, register_t *retval)
                                 * sleeping...
                                 */
                        } else {
-                               /*
-                                * The man page says to return EIDRM.
-                                * Unfortunately, BSD doesn't define that code!
-                                */
 #ifdef EIDRM
                                eval = EIDRM;
 #else
-                               eval = EINVAL;
+                               eval = EINVAL;          /* Ancient past */
 #endif
                        }
                        goto semopout;
@@ -1162,7 +1233,7 @@ semop(struct proc *p, struct semop_args *uap, register_t *retval)
                 * because the sem[] may have been reallocated while
                 * we were sleeping, updating our sem_base pointer.
                 */
-               semptr = &semaptr->sem_base[sopptr->sem_num];
+               semptr = &semakptr->u.sem_base[sopptr->sem_num];
                if (sopptr->sem_op == 0)
                        semptr->semzcnt--;
                else
@@ -1190,7 +1261,7 @@ done:
                        adjval = sops[i].sem_op;
                        if (adjval == 0)
                                continue;
-                       eval = semundo_adjust(p, &suptr, semid,
+                       eval = semundo_adjust(p, &supidx, semid,
                            sops[i].sem_num, -adjval);
                        if (eval == 0)
                                continue;
@@ -1210,13 +1281,13 @@ done:
                                adjval = sops[j].sem_op;
                                if (adjval == 0)
                                        continue;
-                               if (semundo_adjust(p, &suptr, semid,
+                               if (semundo_adjust(p, &supidx, semid,
                                    sops[j].sem_num, adjval) != 0)
                                        panic("semop - can't undo undos");
                        }
 
                        for (j = 0; j < nsops; j++)
-                               semaptr->sem_base[sops[j].sem_num].semval -=
+                               semakptr->u.sem_base[sops[j].sem_num].semval -=
                                    sops[j].sem_op;
 
 #ifdef SEM_DEBUG
@@ -1229,21 +1300,22 @@ done:
        /* We're definitely done - set the sempid's */
        for (i = 0; i < nsops; i++) {
                sopptr = &sops[i];
-               semptr = &semaptr->sem_base[sopptr->sem_num];
+               semptr = &semakptr->u.sem_base[sopptr->sem_num];
                semptr->sempid = p->p_pid;
        }
+       semakptr->u.sem_otime = sysv_semtime();
 
        if (do_wakeup) {
 #ifdef SEM_DEBUG
                printf("semop:  doing wakeup\n");
 #ifdef SEM_WAKEUP
-               sem_wakeup((caddr_t)semaptr);
+               sem_wakeup((caddr_t)semakptr);
 #else
-               wakeup((caddr_t)semaptr);
+               wakeup((caddr_t)semakptr);
 #endif
                printf("semop:  back from wakeup\n");
 #else
-               wakeup((caddr_t)semaptr);
+               wakeup((caddr_t)semakptr);
 #endif
        }
 #ifdef SEM_DEBUG
@@ -1263,8 +1335,9 @@ semopout:
 void
 semexit(struct proc *p)
 {
-       register struct sem_undo *suptr;
-       register struct sem_undo **supptr;
+       register struct sem_undo *suptr = NULL;
+       int suidx;
+       int *supidx;
        int did_something;
 
        /* If we have not allocated our semaphores yet there can't be
@@ -1285,13 +1358,14 @@ semexit(struct proc *p)
         * associated with this process.
         */
 
-       for (supptr = &semu_list; (suptr = *supptr) != NULL;
-           supptr = &suptr->un_next) {
+       for (supidx = &semu_list_idx; (suidx = *supidx) != -1;
+           supidx = &suptr->un_next_idx) {
+               suptr = SEMU(suidx);
                if (suptr->un_proc == p)
                        break;
        }
 
-       if (suptr == NULL)
+       if (suidx == -1)
                goto unlock;
 
 #ifdef SEM_DEBUG
@@ -1308,17 +1382,17 @@ semexit(struct proc *p)
                        int semid;
                        int semnum;
                        int adjval;
-                       struct user_semid_ds *semaptr;
+                       struct semid_kernel *semakptr;
 
                        sueptr = suptr->un_ent;
                        semid = sueptr->une_id;
                        semnum = sueptr->une_num;
                        adjval = sueptr->une_adjval;
 
-                       semaptr = &sema[semid];
-                       if ((semaptr->sem_perm.mode & SEM_ALLOC) == 0)
+                       semakptr = &sema[semid];
+                       if ((semakptr->u.sem_perm.mode & SEM_ALLOC) == 0)
                                panic("semexit - semid not allocated");
-                       if (semnum >= semaptr->sem_nsems)
+                       if (semnum >= semakptr->u.sem_nsems)
                                panic("semexit - semnum out of range");
 
 #ifdef SEM_DEBUG
@@ -1327,19 +1401,19 @@ semexit(struct proc *p)
                               semid,
                               semnum,
                               adjval,
-                              semaptr->sem_base[semnum].semval);
+                              semakptr->u.sem_base[semnum].semval);
 #endif
 
                        if (adjval < 0) {
-                               if (semaptr->sem_base[semnum].semval < -adjval)
-                                       semaptr->sem_base[semnum].semval = 0;
+                               if (semakptr->u.sem_base[semnum].semval < -adjval)
+                                       semakptr->u.sem_base[semnum].semval = 0;
                                else
-                                       semaptr->sem_base[semnum].semval +=
+                                       semakptr->u.sem_base[semnum].semval +=
                                            adjval;
                        } else
-                               semaptr->sem_base[semnum].semval += adjval;
+                               semakptr->u.sem_base[semnum].semval += adjval;
 
-               /* Maybe we should build a list of semaptr's to wake
+               /* Maybe we should build a list of semakptr's to wake
                 * up, finish all access to data structures, release the
                 * subsystem lock, and wake all the processes.  Something
                 * to think about.  It wouldn't buy us anything unless
@@ -1348,9 +1422,9 @@ semexit(struct proc *p)
                 * in the BSD code at once.
                 */
 #ifdef SEM_WAKEUP
-                       sem_wakeup((caddr_t)semaptr);
+                       sem_wakeup((caddr_t)semakptr);
 #else
-                       wakeup((caddr_t)semaptr);
+                       wakeup((caddr_t)semakptr);
 #endif
 #ifdef SEM_DEBUG
                        printf("semexit:  back from wakeup\n");
@@ -1369,7 +1443,7 @@ semexit(struct proc *p)
        printf("removing vector\n");
 #endif
        suptr->un_proc = NULL;
-       *supptr = suptr->un_next;
+       *supidx = suptr->un_next_idx;
 
 unlock:
        /*
@@ -1413,7 +1487,7 @@ sysctl_seminfo(__unused struct sysctl_oid *oidp, void *arg1,
        if ((sem_pool == NULL) && 
                (sema == NULL) && 
                (semu == NULL) && 
-               (semu_list == NULL)) {
+               (semu_list_idx == -1)) {
                        if ((error = SYSCTL_IN(req, arg1, sizeof(int)))) {
                                goto out;
                        }
@@ -1427,19 +1501,19 @@ out:
 
 /* SYSCTL_NODE(_kern, KERN_SYSV, sysv, CTLFLAG_RW, 0, "SYSV"); */
 extern struct sysctl_oid_list sysctl__kern_sysv_children;
-SYSCTL_PROC(_kern_sysv, KSYSV_SEMMNI, semmni, CTLTYPE_INT | CTLFLAG_RW,
+SYSCTL_PROC(_kern_sysv, OID_AUTO, semmni, CTLTYPE_INT | CTLFLAG_RW,
     &limitseminfo.semmni, 0, &sysctl_seminfo ,"I","semmni");
 
-SYSCTL_PROC(_kern_sysv, KSYSV_SEMMNS, semmns, CTLTYPE_INT | CTLFLAG_RW,
+SYSCTL_PROC(_kern_sysv, OID_AUTO, semmns, CTLTYPE_INT | CTLFLAG_RW,
     &limitseminfo.semmns, 0, &sysctl_seminfo ,"I","semmns");
 
-SYSCTL_PROC(_kern_sysv, KSYSV_SEMMNU, semmnu, CTLTYPE_INT | CTLFLAG_RW,
+SYSCTL_PROC(_kern_sysv, OID_AUTO, semmnu, CTLTYPE_INT | CTLFLAG_RW,
     &limitseminfo.semmnu, 0, &sysctl_seminfo ,"I","semmnu");
 
-SYSCTL_PROC(_kern_sysv, KSYSV_SEMMSL, semmsl, CTLTYPE_INT | CTLFLAG_RW,
+SYSCTL_PROC(_kern_sysv, OID_AUTO, semmsl, CTLTYPE_INT | CTLFLAG_RW,
     &limitseminfo.semmsl, 0, &sysctl_seminfo ,"I","semmsl");
     
-SYSCTL_PROC(_kern_sysv, KSYSV_SEMUNE, semume, CTLTYPE_INT | CTLFLAG_RW,
+SYSCTL_PROC(_kern_sysv, OID_AUTO, semume, CTLTYPE_INT | CTLFLAG_RW,
     &limitseminfo.semume, 0, &sysctl_seminfo ,"I","semume");
 
 
@@ -1459,15 +1533,18 @@ IPCS_sem_sysctl(__unused struct sysctl_oid *oidp, __unused void *arg1,
        size_t semid_ds_sz = sizeof(struct user_semid_ds);
        struct proc *p = current_proc();
 
+       if (!IS_64BIT_PROCESS(p)) {
+               ipcs_sz = sizeof(struct IPCS_command);
+               semid_ds_sz = sizeof(struct semid_ds);
+       }
+
        /* Copy in the command structure */
        if ((error = SYSCTL_IN(req, &ipcs, ipcs_sz)) != 0) {
                return(error);
        }
 
-       if (!IS_64BIT_PROCESS(p)) {
-               ipcs_sz = sizeof(struct IPCS_command);
-               semid_ds_sz = sizeof(struct semid_ds);
-       }
+       if (!IS_64BIT_PROCESS(p)) /* convert in place */
+               ipcs.u64.ipcs_data = CAST_USER_ADDR_T(ipcs.u32.ipcs_data);
 
        /* Let us version this interface... */
        if (ipcs.u64.ipcs_magic != IPCS_MAGIC) {
@@ -1499,7 +1576,7 @@ IPCS_sem_sysctl(__unused struct sysctl_oid *oidp, __unused void *arg1,
                        break;
                }
                for( ; cursor < seminfo.semmni; cursor++) {
-                       if (sema[cursor].sem_perm.mode & SEM_ALLOC)
+                       if (sema[cursor].u.sem_perm.mode & SEM_ALLOC)
                                break;
                        continue;
                }
@@ -1508,7 +1585,7 @@ IPCS_sem_sysctl(__unused struct sysctl_oid *oidp, __unused void *arg1,
                        break;
                }
 
-               semid_dsp = &sema[cursor];      /* default: 64 bit */
+               semid_dsp = &sema[cursor].u;    /* default: 64 bit */
 
                /*
                 * If necessary, convert the 64 bit kernel segment
@@ -1539,3 +1616,5 @@ SYSCTL_PROC(_kern_sysv_ipcs, OID_AUTO, sem, CTLFLAG_RW|CTLFLAG_ANYBODY,
        0, 0, IPCS_sem_sysctl,
        "S,IPCS_sem_command",
        "ipcs sem command interface");
+
+#endif /* SYSV_SEM */