/*
- * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2000-2007 Apple Inc. All rights reserved.
*
- * @APPLE_LICENSE_HEADER_START@
- *
- * Copyright (c) 1999-2003 Apple Computer, Inc. All Rights Reserved.
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
* This file contains Original Code and/or Modifications of Original Code
* as defined in and that are subject to the Apple Public Source License
* Version 2.0 (the 'License'). You may not use this file except in
- * compliance with the License. Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this
- * file.
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * unlawful or unlicensed copies of an Apple operating system, or to
+ * circumvent, violate, or enable the circumvention or violation of, any
+ * terms of an Apple operating system software license agreement.
+ *
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this file.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* Please see the License for the specific language governing rights and
* limitations under the License.
*
- * @APPLE_LICENSE_HEADER_END@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
/*
* Implementation of SVID semaphores
/*
* 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/kernel.h>
-#include <sys/proc.h>
-#include <sys/sem.h>
+#include <sys/proc_internal.h>
+#include <sys/kauth.h>
+#include <sys/sem_internal.h>
#include <sys/malloc.h>
#include <mach/mach_types.h>
#include <sys/filedesc.h>
-#include <sys/file.h>
+#include <sys/file_internal.h>
+#include <sys/sysctl.h>
+#include <sys/ipcs.h>
+#include <sys/sysent.h>
+#include <sys/sysproto.h>
+#if CONFIG_MACF
+#include <security/mac_framework.h>
+#endif
-/*#include <sys/sysproto.h>*/
-/*#include <sys/sysent.h>*/
+#include <security/audit/audit.h>
-/* Uncomment this line to see the debugging output */
-/* #define SEM_DEBUG */
+#if SYSV_SEM
-/* Macros to deal with the semaphore subsystem lock. The lock currently uses
- * the semlock_holder static variable as a mutex. NULL means no lock, any
- * value other than NULL means locked. semlock_holder is used because it was
- * present in the code before the Darwin port, and for no other reason.
- * When the time comes to relax the funnel requirements of the kernel only
- * these macros should need to be changed. A spin lock would work well.
- */
-/* Aquire the lock */
-#define SUBSYSTEM_LOCK_AQUIRE(p) { sysv_sem_aquiring_threads++; \
- while (semlock_holder != NULL) \
- (void) tsleep((caddr_t)&semlock_holder, (PZERO - 4), "sysvsem", 0); \
- semlock_holder = p; \
- sysv_sem_aquiring_threads--; }
-/* Release the lock */
-#define SUBSYSTEM_LOCK_RELEASE { semlock_holder = NULL; wakeup((caddr_t)&semlock_holder); }
+/* Uncomment this line to see the debugging output */
+/* #define SEM_DEBUG */
-/* Release the lock and return a value */
-#define UNLOCK_AND_RETURN(ret) { SUBSYSTEM_LOCK_RELEASE; return(ret); }
+/* 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_SUBPROC
+#define M_SYSVSEM M_TEMP
-#if 0
-static void seminit __P((void *));
-SYSINIT(sysv_sem, SI_SUB_SYSV_SEM, SI_ORDER_FIRST, seminit, NULL)
-#endif 0
/* Hard system limits to avoid resource starvation / DOS attacks.
* These are not needed if we can make the semaphore pages swappable.
SEMAEM /* adjust on exit max value */
};
-/* A counter so the module unload code knows when there are no more processes using
- * the sysv_sem code */
-static long sysv_sem_sleeping_threads = 0;
-static long sysv_sem_aquiring_threads = 0;
-struct semctl_args;
-int semctl __P((struct proc *p, struct semctl_args *uap, int *));
-struct semget_args;
-int semget __P((struct proc *p, struct semget_args *uap, int *));
-struct semop_args;
-int semop __P((struct proc *p, struct semop_args *uap, int *));
-struct semconfig_args;
-int semconfig __P((struct proc *p, struct semconfig_args *uap, int *));
-
-
-static struct sem_undo *semu_alloc __P((struct proc *p));
-static int semundo_adjust __P((struct proc *p, struct sem_undo **supptr,
- int semid, int semnum, int adjval));
-static void semundo_clear __P((int semid, int semnum));
-
-typedef int sy_call_t __P((struct proc *, void *, int *));
+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);
/* XXX casting to (sy_call_t *) is bogus, as usual. */
static sy_call_t *semcalls[] = {
(sy_call_t *)semctl, (sy_call_t *)semget,
- (sy_call_t *)semop, (sy_call_t *)semconfig
+ (sy_call_t *)semop
};
-static int semtot = 0; /* # of used semaphores */
-struct semid_ds *sema = NULL; /* semaphore id pool */
-struct sem *sem = NULL; /* semaphore pool */
-static struct sem_undo *semu_list = NULL; /* list of active undo structures */
-struct sem_undo *semu = NULL; /* semaphore undo pool */
+static int semtot = 0; /* # of used semaphores */
+struct semid_kernel *sema = NULL; /* semaphore id pool */
+struct sem *sem_pool = NULL; /* semaphore pool */
+static int semu_list_idx = -1; /* active undo structures */
+struct sem_undo *semu = NULL; /* semaphore undo pool */
-static struct proc *semlock_holder = NULL;
-/* seminit no longer needed. The data structures are grown dynamically */
-void
-seminit()
+void sysv_sem_lock_init(void);
+static lck_grp_t *sysv_sem_subsys_lck_grp;
+static lck_grp_attr_t *sysv_sem_subsys_lck_grp_attr;
+static lck_attr_t *sysv_sem_subsys_lck_attr;
+static lck_mtx_t sysv_sem_subsys_mutex;
+
+#define SYSV_SEM_SUBSYS_LOCK() lck_mtx_lock(&sysv_sem_subsys_mutex)
+#define SYSV_SEM_SUBSYS_UNLOCK() lck_mtx_unlock(&sysv_sem_subsys_mutex)
+
+
+__private_extern__ void
+sysv_sem_lock_init( void )
{
+
+ sysv_sem_subsys_lck_grp_attr = lck_grp_attr_alloc_init();
+
+ 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_mtx_init(&sysv_sem_subsys_mutex, sysv_sem_subsys_lck_grp, sysv_sem_subsys_lck_attr);
+}
+
+static __inline__ user_time_t
+sysv_semtime(void)
+{
+ struct timeval tv;
+ microtime(&tv);
+ return (tv.tv_sec);
}
/*
- * Entry point for all SEM calls
+ * XXX conversion of internal user_time_t to external tume_t loses
+ * XXX precision; not an issue for us now, since we are only ever
+ * XXX setting 32 bits worth of time into it.
+ *
+ * pad field contents are not moved correspondingly; contents will be lost
*
- * In Darwin this is no longer the entry point. It will be removed after
- * the code has been tested better.
+ * NOTE: Source and target may *NOT* overlap! (target is smaller)
*/
-struct semsys_args {
- u_int which;
- int a2;
- int a3;
- int a4;
- int a5;
-};
-int
-semsys(p, uap, retval)
- struct proc *p;
- /* XXX actually varargs. */
- struct semsys_args *uap;
- register_t *retval;
+static void
+semid_ds_kernelto32(struct user_semid_ds *in, struct user32_semid_ds *out)
{
+ out->sem_perm = in->sem_perm;
+ out->sem_base = CAST_DOWN_EXPLICIT(__int32_t,in->sem_base);
+ out->sem_nsems = in->sem_nsems;
+ out->sem_otime = in->sem_otime; /* XXX loses precision */
+ out->sem_ctime = in->sem_ctime; /* XXX loses precision */
+}
- /* The individual calls handling the locking now */
- /*while (semlock_holder != NULL && semlock_holder != p)
- (void) tsleep((caddr_t)&semlock_holder, (PZERO - 4), "semsys", 0);
- */
-
- if (uap->which >= sizeof(semcalls)/sizeof(semcalls[0]))
- return (EINVAL);
- return ((*semcalls[uap->which])(p, &uap->a2, retval));
+static void
+semid_ds_kernelto64(struct user_semid_ds *in, struct user64_semid_ds *out)
+{
+ out->sem_perm = in->sem_perm;
+ out->sem_base = CAST_DOWN_EXPLICIT(__int32_t,in->sem_base);
+ out->sem_nsems = in->sem_nsems;
+ out->sem_otime = in->sem_otime; /* XXX loses precision */
+ out->sem_ctime = in->sem_ctime; /* XXX loses precision */
}
/*
- * Lock or unlock the entire semaphore facility.
+ * pad field contents are not moved correspondingly; contents will be lost
*
- * This will probably eventually evolve into a general purpose semaphore
- * facility status enquiry mechanism (I don't like the "read /dev/kmem"
- * approach currently taken by ipcs and the amount of info that we want
- * to be able to extract for ipcs is probably beyond what the capability
- * of the getkerninfo facility.
+ * NOTE: Source and target may are permitted to overlap! (source is smaller);
+ * this works because we copy fields in order from the end of the struct to
+ * the beginning.
*
- * At the time that the current version of semconfig was written, ipcs is
- * the only user of the semconfig facility. It uses it to ensure that the
- * semaphore facility data structures remain static while it fishes around
- * in /dev/kmem.
+ * XXX use CAST_USER_ADDR_T() for lack of a CAST_USER_TIME_T(); net effect
+ * XXX is the same.
*/
+static void
+semid_ds_32tokernel(struct user32_semid_ds *in, struct user_semid_ds *out)
+{
+ out->sem_ctime = in->sem_ctime;
+ out->sem_otime = in->sem_otime;
+ out->sem_nsems = in->sem_nsems;
+ out->sem_base = (void *)(uintptr_t)in->sem_base;
+ out->sem_perm = in->sem_perm;
+}
-#ifndef _SYS_SYSPROTO_H_
-struct semconfig_args {
- semconfig_ctl_t flag;
-};
-#endif
-
-int
-semconfig(p, uap, retval)
- struct proc *p;
- struct semconfig_args *uap;
- register_t *retval;
+static void
+semid_ds_64tokernel(struct user64_semid_ds *in, struct user_semid_ds *out)
{
- int eval = 0;
+ out->sem_ctime = in->sem_ctime;
+ out->sem_otime = in->sem_otime;
+ out->sem_nsems = in->sem_nsems;
+ out->sem_base = (void *)(uintptr_t)in->sem_base;
+ out->sem_perm = in->sem_perm;
+}
- switch (uap->flag) {
- case SEM_CONFIG_FREEZE:
- SUBSYSTEM_LOCK_AQUIRE(p);
- break;
- case SEM_CONFIG_THAW:
- SUBSYSTEM_LOCK_RELEASE;
- break;
+/*
+ * semsys
+ *
+ * Entry point for all SEM calls: semctl, semget, semop
+ *
+ * Parameters: p Process requesting the call
+ * uap User argument descriptor (see below)
+ * retval Return value of the selected sem call
+ *
+ * Indirect parameters: uap->which sem call to invoke (index in array of sem calls)
+ * uap->a2 User argument descriptor
+ *
+ * Returns: 0 Success
+ * !0 Not success
+ *
+ * Implicit returns: retval Return value of the selected sem call
+ *
+ * DEPRECATED: This interface should not be used to call the other SEM
+ * functions (semctl, semget, semop). The correct usage is
+ * to call the other SEM functions directly.
+ *
+ */
+int
+semsys(struct proc *p, struct semsys_args *uap, int32_t *retval)
+{
- default:
- printf("semconfig: unknown flag parameter value (%d) - ignored\n",
- uap->flag);
- eval = EINVAL;
- break;
- }
+ /* The individual calls handling the locking now */
- *retval = 0;
- return(eval);
+ if (uap->which >= sizeof(semcalls)/sizeof(semcalls[0]))
+ return (EINVAL);
+ return ((*semcalls[uap->which])(p, &uap->a2, retval));
}
-/* Expand the semu array to the given capacity. If the expansion fails
+/*
+ * Expand the semu array to the given capacity. If the expansion fails
* return 0, otherwise return 1.
*
* Assumes we already have the subsystem lock.
*/
static int
-grow_semu_array(newSize)
- int newSize;
+grow_semu_array(int newSize)
{
- register int i, j;
+ register int i;
register struct sem_undo *newSemu;
+
if (newSize <= seminfo.semmnu)
- return 0;
+ return 1;
if (newSize > limitseminfo.semmnu) /* enforce hard limit */
{
#ifdef SEM_DEBUG
#ifdef SEM_DEBUG
printf("growing semu[] from %d to %d\n", seminfo.semmnu, newSize);
#endif
- MALLOC(newSemu, struct sem_undo*, sizeof(struct sem_undo)*newSize,
- M_SYSVSEM, M_WAITOK);
+ MALLOC(newSemu, struct sem_undo *, sizeof (struct sem_undo) * newSize,
+ M_SYSVSEM, M_WAITOK | M_ZERO);
if (NULL == newSemu)
{
#ifdef SEM_DEBUG
return 0;
}
- /* Initialize our structure. */
+ /* copy the old data to the new array */
for (i = 0; i < seminfo.semmnu; i++)
{
newSemu[i] = semu[i];
- for(j = 0; j < SEMUME; j++) /* Is this really needed? */
- newSemu[i].un_ent[j] = semu[i].un_ent[j];
}
- for (i = seminfo.semmnu; i < newSize; i++)
- {
- newSemu[i].un_proc = NULL;
- }
+ /*
+ * The new elements (from newSemu[i] to newSemu[newSize-1]) have their
+ * "un_proc" set to 0 (i.e. NULL) by the M_ZERO flag to MALLOC() above,
+ * so they're already marked as "not in use".
+ */
/* Clean up the old array */
if (semu)
* Assumes we already have the subsystem lock.
*/
static int
-grow_sema_array(newSize)
- int newSize;
+grow_sema_array(int newSize)
{
- register struct semid_ds *newSema;
+ register struct semid_kernel *newSema;
register int i;
if (newSize <= seminfo.semmni)
#ifdef SEM_DEBUG
printf("growing sema[] from %d to %d\n", seminfo.semmni, newSize);
#endif
- MALLOC(newSema, struct semid_ds*, sizeof(struct semid_ds)*newSize,
- M_SYSVSEM, M_WAITOK);
+ MALLOC(newSema, struct semid_kernel *,
+ sizeof (struct semid_kernel) * newSize,
+ M_SYSVSEM, M_WAITOK | M_ZERO);
if (NULL == newSema)
{
#ifdef SEM_DEBUG
return 0;
}
- /* Initialize our new ids, and copy over the old ones */
+ /* copy over the old ids */
for (i = 0; i < seminfo.semmni; i++)
{
newSema[i] = sema[i];
* 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 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++)
{
- newSema[i].sem_base = 0;
- newSema[i].sem_perm.mode = 0;
+ 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
+ * flag to MALLOC() above, so they're already marked as "not in use".
+ */
/* Clean up the old array */
if (sema)
}
/*
- * Expand the sem array to the given capacity. If the expansion fails
+ * Expand the sem_pool array to the given capacity. If the expansion fails
* we return 0 (fail), otherwise we return 1 (success).
*
* Assumes we already hold the subsystem lock.
*/
static int
-grow_sem_array(newSize)
- int newSize;
+grow_sem_pool(int new_pool_size)
{
- register struct sem *newSem = NULL;
- register int i;
+ struct sem *new_sem_pool = NULL;
+ struct sem *sem_free;
+ int i;
- if (newSize < semtot)
+ if (new_pool_size < semtot)
return 0;
- if (newSize > limitseminfo.semmns) /* enforce hard limit */
- {
+ /* enforce hard limit */
+ if (new_pool_size > limitseminfo.semmns) {
#ifdef SEM_DEBUG
printf("semaphore hard limit of %d reached, requested %d\n",
- limitseminfo.semmns, newSize);
+ limitseminfo.semmns, new_pool_size);
#endif
return 0;
}
- newSize = (newSize/SEMMNS_INC + 1) * SEMMNS_INC;
- newSize = newSize > limitseminfo.semmns ? limitseminfo.semmns : newSize;
+
+ new_pool_size = (new_pool_size/SEMMNS_INC + 1) * SEMMNS_INC;
+ new_pool_size = new_pool_size > limitseminfo.semmns ? limitseminfo.semmns : new_pool_size;
#ifdef SEM_DEBUG
- printf("growing sem array from %d to %d\n", seminfo.semmns, newSize);
+ printf("growing sem_pool array from %d to %d\n", seminfo.semmns, new_pool_size);
#endif
- MALLOC(newSem, struct sem*, sizeof(struct sem)*newSize,
- M_SYSVSEM, M_WAITOK);
- if (NULL == newSem)
- {
+ MALLOC(new_sem_pool, struct sem *, sizeof (struct sem) * new_pool_size,
+ M_SYSVSEM, M_WAITOK | M_ZERO);
+ if (NULL == new_sem_pool) {
#ifdef SEM_DEBUG
printf("allocation failed. no changes made.\n");
#endif
}
/* We have our new memory, now copy the old contents over */
- if (sem)
+ if (sem_pool)
for(i = 0; i < seminfo.semmns; i++)
- newSem[i] = sem[i];
+ new_sem_pool[i] = sem_pool[i];
/* 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 */
- {
- if (newSem > sem)
- sema[i].sem_base += newSem - sem;
- else
- sema[i].sem_base -= sem - newSem;
- }
+ for(i = 0; i < seminfo.semmni; i++) {
+ if (sema[i].u.sem_perm.mode & SEM_ALLOC) /* ID in use */
+ sema[i].u.sem_base = new_sem_pool +
+ (sema[i].u.sem_base - sem_pool);
+ }
+
+ sem_free = sem_pool;
+ sem_pool = new_sem_pool;
/* clean up the old array */
- if (sem)
- FREE(sem, M_SYSVSEM);
+ if (sem_free != NULL)
+ FREE(sem_free, M_SYSVSEM);
- sem = newSem;
- seminfo.semmns = newSize;
+ seminfo.semmns = new_pool_size;
#ifdef SEM_DEBUG
printf("expansion complete\n");
#endif
* Assumes we already hold the subsystem lock.
*/
-static struct sem_undo *
-semu_alloc(p)
- struct proc *p;
+static int
+semu_alloc(struct proc *p)
{
register int i;
register struct sem_undo *suptr;
- register struct sem_undo **supptr;
+ int *supidx;
int attempt;
/*
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;
}
}
/* 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
*/
if (!did_something)
if (!grow_semu_array(seminfo.semmnu + 1))
- return(NULL);
+ return -1;
} else {
/*
* The second pass failed even though we freed
panic("semu_alloc - second attempt failed");
}
}
- return (NULL);
+ return -1;
}
/*
*
* Assumes we already hold the subsystem lock.
*/
-
static int
-semundo_adjust(p, supptr, semid, semnum, adjval)
- register struct proc *p;
- struct sem_undo **supptr;
- int semid, semnum;
- int adjval;
+semundo_adjust(struct proc *p, int *supidx, int semid,
+ int semnum, int adjval)
{
register struct sem_undo *suptr;
- register struct undo *sunptr;
+ int suidx;
+ register struct undo *sueptr, **suepptr, *new_sueptr;
int i;
- /* Look for and remember the sem_undo if the caller doesn't provide
- it */
+ /*
+ * 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;
}
}
* Look for the requested entry and adjust it (delete if adjval becomes
* 0).
*/
- sunptr = &suptr->un_ent[0];
- for (i = 0; i < suptr->un_cnt; i++, sunptr++) {
- if (sunptr->un_id != semid || sunptr->un_num != semnum)
+ suptr = SEMU(suidx);
+ new_sueptr = NULL;
+ for (i = 0, suepptr = &suptr->un_ent, sueptr = suptr->un_ent;
+ i < suptr->un_cnt;
+ i++, suepptr = &sueptr->une_next, sueptr = sueptr->une_next) {
+ if (sueptr->une_id != semid || sueptr->une_num != semnum)
continue;
if (adjval == 0)
- sunptr->un_adjval = 0;
+ sueptr->une_adjval = 0;
else
- sunptr->un_adjval += adjval;
- if (sunptr->un_adjval == 0) {
+ sueptr->une_adjval += adjval;
+ if (sueptr->une_adjval == 0) {
suptr->un_cnt--;
- if (i < suptr->un_cnt)
- suptr->un_ent[i] =
- suptr->un_ent[suptr->un_cnt];
+ *suepptr = sueptr->une_next;
+ FREE(sueptr, M_SYSVSEM);
+ sueptr = NULL;
}
- return(0);
+ return 0;
}
/* Didn't find the right entry - create it */
- if (adjval == 0)
- return(0);
- if (suptr->un_cnt != seminfo.semume) {
- sunptr = &suptr->un_ent[suptr->un_cnt];
- suptr->un_cnt++;
- sunptr->un_adjval = adjval;
- sunptr->un_id = semid; sunptr->un_num = semnum;
- } else
- return(EINVAL);
- return(0);
+ if (adjval == 0) {
+ /* no adjustment: no need for a new entry */
+ return 0;
+ }
+
+ if (suptr->un_cnt == limitseminfo.semume) {
+ /* reached the limit number of semaphore undo entries */
+ return EINVAL;
+ }
+
+ /* allocate a new semaphore undo entry */
+ MALLOC(new_sueptr, struct undo *, sizeof (struct undo),
+ M_SYSVSEM, M_WAITOK);
+ if (new_sueptr == NULL) {
+ return ENOMEM;
+ }
+
+ /* fill in the new semaphore undo entry */
+ new_sueptr->une_next = suptr->un_ent;
+ suptr->un_ent = new_sueptr;
+ suptr->un_cnt++;
+ new_sueptr->une_adjval = adjval;
+ new_sueptr->une_id = semid;
+ new_sueptr->une_num = semnum;
+
+ return 0;
}
/* Assumes we already hold the subsystem lock.
*/
static void
-semundo_clear(semid, semnum)
- int semid, semnum;
+semundo_clear(int semid, int semnum)
{
- register struct sem_undo *suptr;
+ struct sem_undo *suptr;
+ int suidx;
- for (suptr = semu_list; suptr != NULL; suptr = suptr->un_next) {
- register struct undo *sunptr = &suptr->un_ent[0];
- register int i = 0;
+ 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) {
- if (sunptr->un_id == semid) {
- if (semnum == -1 || sunptr->un_num == semnum) {
+ if (sueptr->une_id == semid) {
+ if (semnum == -1 || sueptr->une_num == semnum) {
suptr->un_cnt--;
- if (i < suptr->un_cnt) {
- suptr->un_ent[i] =
- suptr->un_ent[suptr->un_cnt];
- continue;
- }
+ *suepptr = sueptr->une_next;
+ FREE(sueptr, M_SYSVSEM);
+ sueptr = *suepptr;
+ continue;
}
if (semnum != -1)
break;
}
- i++, sunptr++;
+ i++;
+ suepptr = &sueptr->une_next;
+ sueptr = sueptr->une_next;
}
}
}
/*
- * Note that the user-mode half of this passes a union, not a pointer
+ * Note that the user-mode half of this passes a union coerced to a
+ * user_addr_t. The union contains either an int or a pointer, and
+ * so we have to coerce it back, variant on whether the calling
+ * process is 64 bit or not. The coercion works for the 'val' element
+ * because the alignment is the same in user and kernel space.
*/
-#ifndef _SYS_SYSPROTO_H_
-struct semctl_args {
- int semid;
- int semnum;
- int cmd;
- union semun arg;
-};
-#endif
-
int
-semctl(p, uap, retval)
- struct proc *p;
- register struct semctl_args *uap;
- register_t *retval;
+semctl(struct proc *p, struct semctl_args *uap, int32_t *retval)
{
int semid = uap->semid;
int semnum = uap->semnum;
int cmd = uap->cmd;
- union semun arg = uap->arg;
- union semun real_arg;
- struct ucred *cred = p->p_ucred;
+ user_semun_t user_arg = (user_semun_t)uap->arg;
+ kauth_cred_t cred = kauth_cred_get();
int i, rval, eval;
- struct semid_ds sbuf;
- register struct semid_ds *semaptr;
+ struct user_semid_ds sbuf;
+ struct semid_kernel *semakptr;
+
+
+ AUDIT_ARG(svipc_cmd, cmd);
+ AUDIT_ARG(svipc_id, semid);
+
+ SYSV_SEM_SUBSYS_LOCK();
- SUBSYSTEM_LOCK_AQUIRE(p);
#ifdef SEM_DEBUG
- printf("call to semctl(%d, %d, %d, 0x%x)\n", semid, semnum, cmd, arg);
+ printf("call to semctl(%d, %d, %d, 0x%qx)\n", semid, semnum, cmd, user_arg);
#endif
semid = IPCID_TO_IX(semid);
- if (semid < 0 || semid >= seminfo.semmsl)
-{
+
+ if (semid < 0 || semid >= seminfo.semmni) {
#ifdef SEM_DEBUG
printf("Invalid semid\n");
#endif
- UNLOCK_AND_RETURN(EINVAL);
-}
+ eval = EINVAL;
+ goto semctlout;
+ }
- semaptr = &sema[semid];
- if ((semaptr->sem_perm.mode & SEM_ALLOC) == 0 ||
- semaptr->sem_perm.seq != IPCID_TO_SEQ(uap->semid))
- UNLOCK_AND_RETURN(EINVAL);
+ 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)))
- UNLOCK_AND_RETURN(eval);
- semaptr->sem_perm.cuid = cred->cr_uid;
- semaptr->sem_perm.uid = cred->cr_uid;
- semtot -= semaptr->sem_nsems;
- for (i = semaptr->sem_base - sem; i < semtot; i++)
- sem[i] = sem[i + semaptr->sem_nsems];
+ if ((eval = ipcperm(cred, &semakptr->u.sem_perm, IPC_M)))
+ goto semctlout;
+
+ 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)))
- UNLOCK_AND_RETURN(eval);
- /*if ((eval = copyin(arg, &real_arg, sizeof(real_arg))) != 0)
- UNLOCK_AND_RETURN(eval);*/
- if ((eval = copyin(arg.buf, (caddr_t)&sbuf,
- sizeof(sbuf))) != 0)
- UNLOCK_AND_RETURN(eval);
- 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 = time_second;
+ if ((eval = ipcperm(cred, &semakptr->u.sem_perm, IPC_M)))
+ goto semctlout;
+
+ if (IS_64BIT_PROCESS(p)) {
+ struct user64_semid_ds ds64;
+ eval = copyin(user_arg.buf, &ds64, sizeof(ds64));
+ semid_ds_64tokernel(&ds64, &sbuf);
+ } else {
+ struct user32_semid_ds ds32;
+ eval = copyin(user_arg.buf, &ds32, sizeof(ds32));
+ semid_ds_32tokernel(&ds32, &sbuf);
+ }
+
+ if (eval != 0) {
+ goto semctlout;
+ }
+
+ 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)))
- UNLOCK_AND_RETURN(eval);
- /*if ((eval = copyin(arg, &real_arg, sizeof(real_arg))) != 0)
- UNLOCK_AND_RETURN(eval);*/
- eval = copyout((caddr_t)semaptr, arg.buf,
- sizeof(struct semid_ds));
+ if ((eval = ipcperm(cred, &semakptr->u.sem_perm, IPC_R)))
+ goto semctlout;
+
+ if (IS_64BIT_PROCESS(p)) {
+ struct user64_semid_ds semid_ds64;
+ bzero(&semid_ds64, sizeof(semid_ds64));
+ semid_ds_kernelto64(&semakptr->u, &semid_ds64);
+ eval = copyout(&semid_ds64, user_arg.buf, sizeof(semid_ds64));
+ } else {
+ struct user32_semid_ds semid_ds32;
+ bzero(&semid_ds32, sizeof(semid_ds32));
+ semid_ds_kernelto32(&semakptr->u, &semid_ds32);
+ eval = copyout(&semid_ds32, user_arg.buf, sizeof(semid_ds32));
+ }
break;
case GETNCNT:
- if ((eval = ipcperm(cred, &semaptr->sem_perm, IPC_R)))
- UNLOCK_AND_RETURN(eval);
- if (semnum < 0 || semnum >= semaptr->sem_nsems)
- UNLOCK_AND_RETURN(EINVAL);
- rval = semaptr->sem_base[semnum].semncnt;
+ if ((eval = ipcperm(cred, &semakptr->u.sem_perm, IPC_R)))
+ goto semctlout;
+ if (semnum < 0 || semnum >= semakptr->u.sem_nsems) {
+ eval = EINVAL;
+ goto semctlout;
+ }
+ rval = semakptr->u.sem_base[semnum].semncnt;
break;
case GETPID:
- if ((eval = ipcperm(cred, &semaptr->sem_perm, IPC_R)))
- UNLOCK_AND_RETURN(eval);
- if (semnum < 0 || semnum >= semaptr->sem_nsems)
- UNLOCK_AND_RETURN(EINVAL);
- rval = semaptr->sem_base[semnum].sempid;
+ if ((eval = ipcperm(cred, &semakptr->u.sem_perm, IPC_R)))
+ goto semctlout;
+ if (semnum < 0 || semnum >= semakptr->u.sem_nsems) {
+ eval = EINVAL;
+ goto semctlout;
+ }
+ rval = semakptr->u.sem_base[semnum].sempid;
break;
case GETVAL:
- if ((eval = ipcperm(cred, &semaptr->sem_perm, IPC_R)))
- UNLOCK_AND_RETURN(eval);
- if (semnum < 0 || semnum >= semaptr->sem_nsems)
- UNLOCK_AND_RETURN(EINVAL);
- rval = semaptr->sem_base[semnum].semval;
+ if ((eval = ipcperm(cred, &semakptr->u.sem_perm, IPC_R)))
+ goto semctlout;
+ if (semnum < 0 || semnum >= semakptr->u.sem_nsems) {
+ eval = EINVAL;
+ goto semctlout;
+ }
+ rval = semakptr->u.sem_base[semnum].semval;
break;
case GETALL:
- if ((eval = ipcperm(cred, &semaptr->sem_perm, IPC_R)))
- UNLOCK_AND_RETURN(eval);
- /*if ((eval = copyin(arg, &real_arg, sizeof(real_arg))) != 0)
- UNLOCK_AND_RETURN(eval);*/
- for (i = 0; i < semaptr->sem_nsems; i++) {
- eval = copyout((caddr_t)&semaptr->sem_base[i].semval,
- &arg.array[i], sizeof(arg.array[0]));
+ if ((eval = ipcperm(cred, &semakptr->u.sem_perm, IPC_R)))
+ goto semctlout;
+/* XXXXXXXXXXXXXXXX TBD XXXXXXXXXXXXXXXX */
+ for (i = 0; i < semakptr->u.sem_nsems; i++) {
+ /* XXX could be done in one go... */
+ eval = copyout((caddr_t)&semakptr->u.sem_base[i].semval,
+ user_arg.array + (i * sizeof(unsigned short)),
+ sizeof(unsigned short));
if (eval != 0)
break;
}
break;
case GETZCNT:
- if ((eval = ipcperm(cred, &semaptr->sem_perm, IPC_R)))
- UNLOCK_AND_RETURN(eval);
- if (semnum < 0 || semnum >= semaptr->sem_nsems)
- UNLOCK_AND_RETURN(EINVAL);
- rval = semaptr->sem_base[semnum].semzcnt;
+ if ((eval = ipcperm(cred, &semakptr->u.sem_perm, IPC_R)))
+ goto semctlout;
+ if (semnum < 0 || semnum >= semakptr->u.sem_nsems) {
+ eval = EINVAL;
+ goto semctlout;
+ }
+ 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
- UNLOCK_AND_RETURN(eval);
+ 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");
#endif
- UNLOCK_AND_RETURN(EINVAL);
+ eval = EINVAL;
+ goto semctlout;
}
- /*if ((eval = copyin(arg, &real_arg, sizeof(real_arg))) != 0)
+
+ /*
+ * Cast down a pointer instead of using 'val' member directly
+ * to avoid introducing endieness and a pad field into the
+ * header file. Ugly, but it works.
+ */
+ u_int newsemval = CAST_DOWN_EXPLICIT(u_int, user_arg.buf);
+
+ /*
+ * The check is being performed as unsigned values to match
+ * eventual destination
+ */
+ if (newsemval > (u_int)seminfo.semvmx)
{
#ifdef SEM_DEBUG
- printf("Error during value copyin\n");
+ printf("Out of range sem value for set\n");
#endif
- UNLOCK_AND_RETURN(eval);
- }*/
- semaptr->sem_base[semnum].semval = arg.val;
+ eval = ERANGE;
+ goto semctlout;
+ }
+ semakptr->u.sem_base[semnum].semval = newsemval;
+ 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)))
- UNLOCK_AND_RETURN(eval);
- /*if ((eval = copyin(arg, &real_arg, sizeof(real_arg))) != 0)
- UNLOCK_AND_RETURN(eval);*/
- for (i = 0; i < semaptr->sem_nsems; i++) {
- eval = copyin(&arg.array[i],
- (caddr_t)&semaptr->sem_base[i].semval,
- sizeof(arg.array[0]));
+ if ((eval = ipcperm(cred, &semakptr->u.sem_perm, IPC_W)))
+ goto semctlout;
+/*** XXXXXXXXXXXX TBD ********/
+ 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)&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:
- UNLOCK_AND_RETURN(EINVAL);
+ eval = EINVAL;
+ goto semctlout;
}
if (eval == 0)
*retval = rval;
- UNLOCK_AND_RETURN(eval);
+semctlout:
+ SYSV_SEM_SUBSYS_UNLOCK();
+ return(eval);
}
-#ifndef _SYS_SYSPROTO_H_
-struct semget_args {
- key_t key;
- int nsems;
- int semflg;
-};
-#endif
-
int
-semget(p, uap, retval)
- struct proc *p;
- register struct semget_args *uap;
- register_t *retval;
+semget(__unused struct proc *p, struct semget_args *uap, int32_t *retval)
{
int semid, eval;
int key = uap->key;
int nsems = uap->nsems;
int semflg = uap->semflg;
- struct ucred *cred = p->p_ucred;
+ kauth_cred_t cred = kauth_cred_get();
- SUBSYSTEM_LOCK_AQUIRE(p);
#ifdef SEM_DEBUG
if (key != IPC_PRIVATE)
printf("semget(0x%x, %d, 0%o)\n", key, nsems, semflg);
else
printf("semget(IPC_PRIVATE, %d, 0%o)\n", nsems, semflg);
#endif
+
+
+ SYSV_SEM_SUBSYS_LOCK();
+
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)))
- UNLOCK_AND_RETURN(eval);
- if (nsems > 0 && sema[semid].sem_nsems < nsems) {
+ goto semgetout;
+ if (nsems < 0 || sema[semid].u.sem_nsems < nsems) {
#ifdef SEM_DEBUG
printf("too small\n");
#endif
- UNLOCK_AND_RETURN(EINVAL);
+ eval = EINVAL;
+ goto semgetout;
}
if ((semflg & IPC_CREAT) && (semflg & IPC_EXCL)) {
#ifdef SEM_DEBUG
printf("not exclusive\n");
#endif
- UNLOCK_AND_RETURN(EEXIST);
+ eval = EEXIST;
+ goto semgetout;
}
+#if CONFIG_MACF
+ eval = mac_sysvsem_check_semget(cred, &sema[semid]);
+ if (eval)
+ goto semgetout;
+#endif
goto found;
}
}
printf("need to allocate an id for the request\n");
#endif
if (key == IPC_PRIVATE || (semflg & IPC_CREAT)) {
- if (nsems <= 0 || nsems > seminfo.semmsl) {
+ if (nsems <= 0 || nsems > limitseminfo.semmsl) {
#ifdef SEM_DEBUG
printf("nsems out of range (0<%d<=%d)\n", nsems,
seminfo.semmsl);
#endif
- UNLOCK_AND_RETURN(EINVAL);
+ eval = EINVAL;
+ goto semgetout;
}
if (nsems > seminfo.semmns - semtot) {
#ifdef SEM_DEBUG
printf("not enough semaphores left (need %d, got %d)\n",
nsems, seminfo.semmns - semtot);
#endif
- if (!grow_sem_array(semtot + nsems))
- {
+ if (!grow_sem_pool(semtot + nsems)) {
#ifdef SEM_DEBUG
printf("failed to grow the sem array\n");
#endif
- UNLOCK_AND_RETURN(ENOSPC);
+ eval = ENOSPC;
+ goto semgetout;
}
}
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) {
#ifdef SEM_DEBUG
printf("failed to grow sema array\n");
#endif
- UNLOCK_AND_RETURN(ENOSPC);
+ eval = ENOSPC;
+ goto semgetout;
}
}
#ifdef SEM_DEBUG
printf("semid %d is available\n", semid);
#endif
- sema[semid].sem_perm.key = key;
- sema[semid].sem_perm.cuid = cred->cr_uid;
- sema[semid].sem_perm.uid = cred->cr_uid;
- 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 = time_second;
- sema[semid].sem_base = &sem[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 = kauth_cred_getgid(cred);
+ sema[semid].u.sem_perm.gid = kauth_cred_getgid(cred);
+ 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,
- &sem[semtot]);
+ printf("sembase = 0x%x, next = 0x%x\n", sema[semid].u.sem_base,
+ &sem_pool[semtot]);
#endif
} else {
#ifdef SEM_DEBUG
printf("didn't find it and wasn't asked to create it\n");
#endif
- UNLOCK_AND_RETURN(ENOENT);
+ eval = ENOENT;
+ goto semgetout;
}
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);
#endif
- SUBSYSTEM_LOCK_RELEASE;
- return(0);
-}
+ eval = 0;
-#ifndef _SYS_SYSPROTO_H_
-struct semop_args {
- int semid;
- struct sembuf *sops;
- int nsops;
-};
-#endif
+semgetout:
+ SYSV_SEM_SUBSYS_UNLOCK();
+ return(eval);
+}
int
-semop(p, uap, retval)
- struct proc *p;
- register struct semop_args *uap;
- register_t *retval;
+semop(struct proc *p, struct semop_args *uap, int32_t *retval)
{
int semid = uap->semid;
int nsops = uap->nsops;
- struct sembuf sops[MAX_SOPS];
- register struct semid_ds *semaptr;
- register struct sembuf *sopptr;
- register struct sem *semptr;
- struct sem_undo *suptr = NULL;
- struct ucred *cred = p->p_ucred;
+ struct sembuf sops[seminfo.semopm];
+ register struct semid_kernel *semakptr;
+ register struct sembuf *sopptr = NULL; /* protected by 'semptr' */
+ register struct sem *semptr = NULL; /* protected by 'if' */
+ int supidx = -1;
int i, j, eval;
int do_wakeup, do_undos;
- SUBSYSTEM_LOCK_AQUIRE(p);
+ AUDIT_ARG(svipc_id, uap->semid);
+
+ SYSV_SEM_SUBSYS_LOCK();
+
#ifdef SEM_DEBUG
printf("call to semop(%d, 0x%x, %d)\n", semid, sops, nsops);
#endif
semid = IPCID_TO_IX(semid); /* Convert back to zero origin */
- if (semid < 0 || semid >= seminfo.semmsl)
- UNLOCK_AND_RETURN(EINVAL);
+ if (semid < 0 || semid >= seminfo.semmni) {
+ eval = EINVAL;
+ goto semopout;
+ }
- semaptr = &sema[semid];
- if ((semaptr->sem_perm.mode & SEM_ALLOC) == 0)
- UNLOCK_AND_RETURN(EINVAL);
- if (semaptr->sem_perm.seq != IPCID_TO_SEQ(uap->semid))
- UNLOCK_AND_RETURN(EINVAL);
+ semakptr = &sema[semid];
+ if ((semakptr->u.sem_perm.mode & SEM_ALLOC) == 0) {
+ eval = EINVAL;
+ goto semopout;
+ }
+ if (semakptr->u.sem_perm._seq != IPCID_TO_SEQ(uap->semid)) {
+ eval = EINVAL;
+ goto semopout;
+ }
- if ((eval = ipcperm(cred, &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
- UNLOCK_AND_RETURN(eval);
+ goto semopout;
}
- if (nsops > MAX_SOPS) {
+ if (nsops < 0 || nsops > seminfo.semopm) {
#ifdef SEM_DEBUG
- printf("too many sops (max=%d, nsops=%d)\n", MAX_SOPS, nsops);
+ printf("too many sops (max=%d, nsops=%d)\n",
+ seminfo.semopm, nsops);
#endif
- UNLOCK_AND_RETURN(E2BIG);
+ eval = E2BIG;
+ goto semopout;
}
-
- if ((eval = copyin(uap->sops, &sops, nsops * sizeof(sops[0]))) != 0) {
+
+ /* OK for LP64, since sizeof(struct sembuf) is currently invariant */
+ if ((eval = copyin(uap->sops, &sops, nsops * sizeof(struct sembuf))) != 0) {
#ifdef SEM_DEBUG
printf("eval = %d from copyin(%08x, %08x, %ld)\n", eval,
- uap->sops, &sops, nsops * sizeof(sops[0]));
+ uap->sops, &sops, nsops * sizeof(struct sembuf));
#endif
- UNLOCK_AND_RETURN(eval);
+ 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
+
/*
* Loop trying to satisfy the vector of requests.
* If we reach a point where we must wait, any requests already
for (i = 0; i < nsops; i++) {
sopptr = &sops[i];
- if (sopptr->sem_num >= semaptr->sem_nsems)
- UNLOCK_AND_RETURN(EFBIG);
+ 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
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;
/*
* If the request that we couldn't satisfy has the
* NOWAIT flag set then return with EAGAIN.
*/
- if (sopptr->sem_flg & IPC_NOWAIT)
- UNLOCK_AND_RETURN(EAGAIN);
+ if (sopptr->sem_flg & IPC_NOWAIT) {
+ eval = EAGAIN;
+ goto semopout;
+ }
if (sopptr->sem_op == 0)
semptr->semzcnt++;
* waiting for. We will get the lock back after we
* wake up.
*/
- SUBSYSTEM_LOCK_RELEASE;
- sysv_sem_sleeping_threads++;
- eval = tsleep((caddr_t)semaptr, (PZERO - 4) | PCATCH,
+ eval = msleep((caddr_t)semakptr, &sysv_sem_subsys_mutex , (PZERO - 4) | PCATCH,
"semwait", 0);
- sysv_sem_sleeping_threads--;
#ifdef SEM_DEBUG
printf("semop: good morning (eval=%d)!\n", eval);
#endif
- /* There is no need to get the lock if we are just
- * going to return without performing more semaphore
- * operations.
- */
- if (eval != 0)
- return(EINTR);
-
- SUBSYSTEM_LOCK_AQUIRE(p); /* Get it back */
- suptr = NULL; /* sem_undo may have been reallocated */
- semaptr = &sema[semid]; /* sema may have been reallocated */
+ if (eval != 0) {
+ eval = EINTR;
+ }
+ /*
+ * IMPORTANT: while we were asleep, the semaphore array might
+ * have been reallocated somewhere else (see grow_sema_array()).
+ * When we wake up, we have to re-lookup the semaphore
+ * structures and re-validate them.
+ */
-#ifdef SEM_DEBUG
- printf("semop: good morning!\n");
-#endif
+ 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)) {
+ 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
+ * the semaphore disappeared while we were
+ * sleeping...
+ */
+ } else {
#ifdef EIDRM
- UNLOCK_AND_RETURN(EIDRM);
+ eval = EIDRM;
#else
- UNLOCK_AND_RETURN(EINVAL);
+ eval = EINVAL; /* Ancient past */
#endif
+ }
+ goto semopout;
}
/*
* 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
semptr->semncnt--;
+
+ if (eval != 0) { /* EINTR */
+ goto semopout;
+ }
}
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;
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
printf("eval = %d from semundo_adjust\n", eval);
#endif
- UNLOCK_AND_RETURN(eval);
+ goto semopout;
} /* loop through the sops */
} /* if (do_undos) */
/* 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();
- /* Do a wakeup if any semaphore was up'd.
- * we will release our lock on the semaphore subsystem before
- * we wakeup other processes to prevent a little thrashing.
- * Note that this is fine because we are done using the
- * semaphore structures at this point in time. We only use
- * a local variable pointer value, and the retval
- * parameter.
- * Note 2: Future use of sem_wakeup may reqiure the lock.
- */
- SUBSYSTEM_LOCK_RELEASE;
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
printf("semop: done\n");
#endif
*retval = 0;
- return(0);
+ eval = 0;
+semopout:
+ SYSV_SEM_SUBSYS_UNLOCK();
+ return(eval);
}
/*
* semaphores.
*/
void
-semexit(p)
- struct proc *p;
+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
* anything to undo, but we need the lock to prevent
* dynamic memory race conditions.
*/
- SUBSYSTEM_LOCK_AQUIRE(p);
- if (!sem)
+ SYSV_SEM_SUBSYS_LOCK();
+
+ if (!sem_pool)
{
- SUBSYSTEM_LOCK_RELEASE;
+ SYSV_SEM_SUBSYS_UNLOCK();
return;
}
did_something = 0;
* 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
* If there are any active undo elements then process them.
*/
if (suptr->un_cnt > 0) {
- int ix;
+ while (suptr->un_ent != NULL) {
+ struct undo *sueptr;
+ int semid;
+ int semnum;
+ int adjval;
+ struct semid_kernel *semakptr;
- for (ix = 0; ix < suptr->un_cnt; ix++) {
- int semid = suptr->un_ent[ix].un_id;
- int semnum = suptr->un_ent[ix].un_num;
- int adjval = suptr->un_ent[ix].un_adjval;
- struct semid_ds *semaptr;
+ 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
printf("semexit: %08x id=%d num=%d(adj=%d) ; sem=%d\n",
- suptr->un_proc, suptr->un_ent[ix].un_id,
- suptr->un_ent[ix].un_num,
- suptr->un_ent[ix].un_adjval,
- semaptr->sem_base[semnum].semval);
+ suptr->un_proc,
+ semid,
+ semnum,
+ adjval,
+ 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
- * wakeup had the potential to block, or the syscall
- * funnel state was changed to allow multiple threads
- * in the BSD code at once.
+ * to think about.
*/
#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");
#endif
+ suptr->un_cnt--;
+ suptr->un_ent = sueptr->une_next;
+ FREE(sueptr, M_SYSVSEM);
+ sueptr = NULL;
}
}
printf("removing vector\n");
#endif
suptr->un_proc = NULL;
- *supptr = suptr->un_next;
+ *supidx = suptr->un_next_idx;
unlock:
/*
* same leaky semaphore problem.
*/
- SUBSYSTEM_LOCK_RELEASE;
+ SYSV_SEM_SUBSYS_UNLOCK();
+}
+
+
+/* (struct sysctl_oid *oidp, void *arg1, int arg2, \
+ struct sysctl_req *req) */
+static int
+sysctl_seminfo(__unused struct sysctl_oid *oidp, void *arg1,
+ __unused int arg2, struct sysctl_req *req)
+{
+ int error = 0;
+
+ error = SYSCTL_OUT(req, arg1, sizeof(int));
+ if (error || req->newptr == USER_ADDR_NULL)
+ return(error);
+
+ SYSV_SEM_SUBSYS_LOCK();
+
+ /* Set the values only if shared memory is not initialised */
+ if ((sem_pool == NULL) &&
+ (sema == NULL) &&
+ (semu == NULL) &&
+ (semu_list_idx == -1)) {
+ if ((error = SYSCTL_IN(req, arg1, sizeof(int)))) {
+ goto out;
+ }
+ } else
+ error = EINVAL;
+out:
+ SYSV_SEM_SUBSYS_UNLOCK();
+ return(error);
+
+}
+
+/* SYSCTL_NODE(_kern, KERN_SYSV, sysv, CTLFLAG_RW, 0, "SYSV"); */
+extern struct sysctl_oid_list sysctl__kern_sysv_children;
+SYSCTL_PROC(_kern_sysv, OID_AUTO, semmni, CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED,
+ &limitseminfo.semmni, 0, &sysctl_seminfo ,"I","semmni");
+
+SYSCTL_PROC(_kern_sysv, OID_AUTO, semmns, CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED,
+ &limitseminfo.semmns, 0, &sysctl_seminfo ,"I","semmns");
+
+SYSCTL_PROC(_kern_sysv, OID_AUTO, semmnu, CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED,
+ &limitseminfo.semmnu, 0, &sysctl_seminfo ,"I","semmnu");
+
+SYSCTL_PROC(_kern_sysv, OID_AUTO, semmsl, CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED,
+ &limitseminfo.semmsl, 0, &sysctl_seminfo ,"I","semmsl");
+
+SYSCTL_PROC(_kern_sysv, OID_AUTO, semume, CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED,
+ &limitseminfo.semume, 0, &sysctl_seminfo ,"I","semume");
+
+
+static int
+IPCS_sem_sysctl(__unused struct sysctl_oid *oidp, __unused void *arg1,
+ __unused int arg2, struct sysctl_req *req)
+{
+ int error;
+ int cursor;
+ union {
+ struct user32_IPCS_command u32;
+ struct user_IPCS_command u64;
+ } ipcs;
+ struct user32_semid_ds semid_ds32; /* post conversion, 32 bit version */
+ struct user64_semid_ds semid_ds64; /* post conversion, 64 bit version */
+ void *semid_dsp;
+ size_t ipcs_sz;
+ size_t semid_ds_sz;
+ struct proc *p = current_proc();
+
+ if (IS_64BIT_PROCESS(p)) {
+ ipcs_sz = sizeof(struct user_IPCS_command);
+ semid_ds_sz = sizeof(struct user64_semid_ds);
+ } else {
+ ipcs_sz = sizeof(struct user32_IPCS_command);
+ semid_ds_sz = sizeof(struct user32_semid_ds);
+ }
+
+ /* Copy in the command structure */
+ if ((error = SYSCTL_IN(req, &ipcs, ipcs_sz)) != 0) {
+ return(error);
+ }
+
+ 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) {
+ return(EINVAL);
+ }
+
+ SYSV_SEM_SUBSYS_LOCK();
+ switch(ipcs.u64.ipcs_op) {
+ case IPCS_SEM_CONF: /* Obtain global configuration data */
+ if (ipcs.u64.ipcs_datalen != sizeof(struct seminfo)) {
+ error = ERANGE;
+ break;
+ }
+ if (ipcs.u64.ipcs_cursor != 0) { /* fwd. compat. */
+ error = EINVAL;
+ break;
+ }
+ error = copyout(&seminfo, ipcs.u64.ipcs_data, ipcs.u64.ipcs_datalen);
+ break;
+
+ case IPCS_SEM_ITER: /* Iterate over existing segments */
+ cursor = ipcs.u64.ipcs_cursor;
+ if (cursor < 0 || cursor >= seminfo.semmni) {
+ error = ERANGE;
+ break;
+ }
+ if (ipcs.u64.ipcs_datalen != (int)semid_ds_sz ) {
+ error = EINVAL;
+ break;
+ }
+ for( ; cursor < seminfo.semmni; cursor++) {
+ if (sema[cursor].u.sem_perm.mode & SEM_ALLOC)
+ break;
+ continue;
+ }
+ if (cursor == seminfo.semmni) {
+ error = ENOENT;
+ break;
+ }
+
+ semid_dsp = &sema[cursor].u; /* default: 64 bit */
+
+ /*
+ * If necessary, convert the 64 bit kernel segment
+ * descriptor to a 32 bit user one.
+ */
+ if (!IS_64BIT_PROCESS(p)) {
+ bzero(&semid_ds32, sizeof(semid_ds32));
+ semid_ds_kernelto32(semid_dsp, &semid_ds32);
+ semid_dsp = &semid_ds32;
+ } else {
+ bzero(&semid_ds64, sizeof(semid_ds64));
+ semid_ds_kernelto64(semid_dsp, &semid_ds64);
+ semid_dsp = &semid_ds64;
+ }
+
+ error = copyout(semid_dsp, ipcs.u64.ipcs_data, ipcs.u64.ipcs_datalen);
+ if (!error) {
+ /* update cursor */
+ ipcs.u64.ipcs_cursor = cursor + 1;
+
+ if (!IS_64BIT_PROCESS(p)) /* convert in place */
+ ipcs.u32.ipcs_data = CAST_DOWN_EXPLICIT(user32_addr_t,ipcs.u64.ipcs_data);
+
+ error = SYSCTL_OUT(req, &ipcs, ipcs_sz);
+ }
+ break;
+
+ default:
+ error = EINVAL;
+ break;
+ }
+ SYSV_SEM_SUBSYS_UNLOCK();
+ return(error);
}
+SYSCTL_DECL(_kern_sysv_ipcs);
+SYSCTL_PROC(_kern_sysv_ipcs, OID_AUTO, sem, CTLFLAG_RW | CTLFLAG_ANYBODY | CTLFLAG_LOCKED,
+ 0, 0, IPCS_sem_sysctl,
+ "S,IPCS_sem_command",
+ "ipcs sem command interface");
+
+#endif /* SYSV_SEM */
projects / apple / xnu.git / blobdiff