[PATCH] IPC namespace - sem

IPC namespace support for IPC sem code.

Signed-off-by: Pavel Emelianiov <xemul@openvz.org>
Signed-off-by: Kirill Korotaev <dev@openvz.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Kirill Korotaev 2006-10-02 02:18:22 -07:00 committed by Linus Torvalds
parent 1e78693738
commit e38935341a

201
ipc/sem.c
View File

@ -64,6 +64,10 @@
*
* support for audit of ipc object properties and permission changes
* Dustin Kirkland <dustin.kirkland@us.ibm.com>
*
* namespaces support
* OpenVZ, SWsoft Inc.
* Pavel Emelianov <xemul@openvz.org>
*/
#include <linux/slab.h>
@ -78,22 +82,25 @@
#include <linux/capability.h>
#include <linux/seq_file.h>
#include <linux/mutex.h>
#include <linux/nsproxy.h>
#include <asm/uaccess.h>
#include "util.h"
#define sem_ids(ns) (*((ns)->ids[IPC_SEM_IDS]))
#define sem_lock(id) ((struct sem_array*)ipc_lock(&sem_ids,id))
#define sem_unlock(sma) ipc_unlock(&(sma)->sem_perm)
#define sem_rmid(id) ((struct sem_array*)ipc_rmid(&sem_ids,id))
#define sem_checkid(sma, semid) \
ipc_checkid(&sem_ids,&sma->sem_perm,semid)
#define sem_buildid(id, seq) \
ipc_buildid(&sem_ids, id, seq)
static struct ipc_ids sem_ids;
#define sem_lock(ns, id) ((struct sem_array*)ipc_lock(&sem_ids(ns), id))
#define sem_unlock(sma) ipc_unlock(&(sma)->sem_perm)
#define sem_rmid(ns, id) ((struct sem_array*)ipc_rmid(&sem_ids(ns), id))
#define sem_checkid(ns, sma, semid) \
ipc_checkid(&sem_ids(ns),&sma->sem_perm,semid)
#define sem_buildid(ns, id, seq) \
ipc_buildid(&sem_ids(ns), id, seq)
static int newary (key_t, int, int);
static void freeary (struct sem_array *sma, int id);
static struct ipc_ids init_sem_ids;
static int newary(struct ipc_namespace *, key_t, int, int);
static void freeary(struct ipc_namespace *ns, struct sem_array *sma, int id);
#ifdef CONFIG_PROC_FS
static int sysvipc_sem_proc_show(struct seq_file *s, void *it);
#endif
@ -110,22 +117,61 @@ static int sysvipc_sem_proc_show(struct seq_file *s, void *it);
*
*/
int sem_ctls[4] = {SEMMSL, SEMMNS, SEMOPM, SEMMNI};
#define sc_semmsl (sem_ctls[0])
#define sc_semmns (sem_ctls[1])
#define sc_semopm (sem_ctls[2])
#define sc_semmni (sem_ctls[3])
#define sc_semmsl sem_ctls[0]
#define sc_semmns sem_ctls[1]
#define sc_semopm sem_ctls[2]
#define sc_semmni sem_ctls[3]
static int used_sems;
static void __ipc_init __sem_init_ns(struct ipc_namespace *ns, struct ipc_ids *ids)
{
ns->ids[IPC_SEM_IDS] = ids;
ns->sc_semmsl = SEMMSL;
ns->sc_semmns = SEMMNS;
ns->sc_semopm = SEMOPM;
ns->sc_semmni = SEMMNI;
ns->used_sems = 0;
ipc_init_ids(ids, ns->sc_semmni);
}
#ifdef CONFIG_IPC_NS
int sem_init_ns(struct ipc_namespace *ns)
{
struct ipc_ids *ids;
ids = kmalloc(sizeof(struct ipc_ids), GFP_KERNEL);
if (ids == NULL)
return -ENOMEM;
__sem_init_ns(ns, ids);
return 0;
}
void sem_exit_ns(struct ipc_namespace *ns)
{
int i;
struct sem_array *sma;
mutex_lock(&sem_ids(ns).mutex);
for (i = 0; i <= sem_ids(ns).max_id; i++) {
sma = sem_lock(ns, i);
if (sma == NULL)
continue;
freeary(ns, sma, i);
}
mutex_unlock(&sem_ids(ns).mutex);
kfree(ns->ids[IPC_SEM_IDS]);
ns->ids[IPC_SEM_IDS] = NULL;
}
#endif
void __init sem_init (void)
{
used_sems = 0;
ipc_init_ids(&sem_ids,sc_semmni);
__sem_init_ns(&init_ipc_ns, &init_sem_ids);
ipc_init_proc_interface("sysvipc/sem",
" key semid perms nsems uid gid cuid cgid otime ctime\n",
&sem_ids,
sysvipc_sem_proc_show);
IPC_SEM_IDS, sysvipc_sem_proc_show);
}
/*
@ -162,7 +208,7 @@ void __init sem_init (void)
*/
#define IN_WAKEUP 1
static int newary (key_t key, int nsems, int semflg)
static int newary (struct ipc_namespace *ns, key_t key, int nsems, int semflg)
{
int id;
int retval;
@ -171,7 +217,7 @@ static int newary (key_t key, int nsems, int semflg)
if (!nsems)
return -EINVAL;
if (used_sems + nsems > sc_semmns)
if (ns->used_sems + nsems > ns->sc_semmns)
return -ENOSPC;
size = sizeof (*sma) + nsems * sizeof (struct sem);
@ -191,15 +237,15 @@ static int newary (key_t key, int nsems, int semflg)
return retval;
}
id = ipc_addid(&sem_ids, &sma->sem_perm, sc_semmni);
id = ipc_addid(&sem_ids(ns), &sma->sem_perm, ns->sc_semmni);
if(id == -1) {
security_sem_free(sma);
ipc_rcu_putref(sma);
return -ENOSPC;
}
used_sems += nsems;
ns->used_sems += nsems;
sma->sem_id = sem_buildid(id, sma->sem_perm.seq);
sma->sem_id = sem_buildid(ns, id, sma->sem_perm.seq);
sma->sem_base = (struct sem *) &sma[1];
/* sma->sem_pending = NULL; */
sma->sem_pending_last = &sma->sem_pending;
@ -215,29 +261,32 @@ asmlinkage long sys_semget (key_t key, int nsems, int semflg)
{
int id, err = -EINVAL;
struct sem_array *sma;
struct ipc_namespace *ns;
if (nsems < 0 || nsems > sc_semmsl)
ns = current->nsproxy->ipc_ns;
if (nsems < 0 || nsems > ns->sc_semmsl)
return -EINVAL;
mutex_lock(&sem_ids.mutex);
mutex_lock(&sem_ids(ns).mutex);
if (key == IPC_PRIVATE) {
err = newary(key, nsems, semflg);
} else if ((id = ipc_findkey(&sem_ids, key)) == -1) { /* key not used */
err = newary(ns, key, nsems, semflg);
} else if ((id = ipc_findkey(&sem_ids(ns), key)) == -1) { /* key not used */
if (!(semflg & IPC_CREAT))
err = -ENOENT;
else
err = newary(key, nsems, semflg);
err = newary(ns, key, nsems, semflg);
} else if (semflg & IPC_CREAT && semflg & IPC_EXCL) {
err = -EEXIST;
} else {
sma = sem_lock(id);
sma = sem_lock(ns, id);
BUG_ON(sma==NULL);
if (nsems > sma->sem_nsems)
err = -EINVAL;
else if (ipcperms(&sma->sem_perm, semflg))
err = -EACCES;
else {
int semid = sem_buildid(id, sma->sem_perm.seq);
int semid = sem_buildid(ns, id, sma->sem_perm.seq);
err = security_sem_associate(sma, semflg);
if (!err)
err = semid;
@ -245,7 +294,7 @@ asmlinkage long sys_semget (key_t key, int nsems, int semflg)
sem_unlock(sma);
}
mutex_unlock(&sem_ids.mutex);
mutex_unlock(&sem_ids(ns).mutex);
return err;
}
@ -444,7 +493,7 @@ static int count_semzcnt (struct sem_array * sma, ushort semnum)
* the spinlock for this semaphore set hold. sem_ids.mutex remains locked
* on exit.
*/
static void freeary (struct sem_array *sma, int id)
static void freeary (struct ipc_namespace *ns, struct sem_array *sma, int id)
{
struct sem_undo *un;
struct sem_queue *q;
@ -472,10 +521,10 @@ static void freeary (struct sem_array *sma, int id)
}
/* Remove the semaphore set from the ID array*/
sma = sem_rmid(id);
sma = sem_rmid(ns, id);
sem_unlock(sma);
used_sems -= sma->sem_nsems;
ns->used_sems -= sma->sem_nsems;
size = sizeof (*sma) + sma->sem_nsems * sizeof (struct sem);
security_sem_free(sma);
ipc_rcu_putref(sma);
@ -503,7 +552,8 @@ static unsigned long copy_semid_to_user(void __user *buf, struct semid64_ds *in,
}
}
static int semctl_nolock(int semid, int semnum, int cmd, int version, union semun arg)
static int semctl_nolock(struct ipc_namespace *ns, int semid, int semnum,
int cmd, int version, union semun arg)
{
int err = -EINVAL;
struct sem_array *sma;
@ -520,24 +570,24 @@ static int semctl_nolock(int semid, int semnum, int cmd, int version, union semu
return err;
memset(&seminfo,0,sizeof(seminfo));
seminfo.semmni = sc_semmni;
seminfo.semmns = sc_semmns;
seminfo.semmsl = sc_semmsl;
seminfo.semopm = sc_semopm;
seminfo.semmni = ns->sc_semmni;
seminfo.semmns = ns->sc_semmns;
seminfo.semmsl = ns->sc_semmsl;
seminfo.semopm = ns->sc_semopm;
seminfo.semvmx = SEMVMX;
seminfo.semmnu = SEMMNU;
seminfo.semmap = SEMMAP;
seminfo.semume = SEMUME;
mutex_lock(&sem_ids.mutex);
mutex_lock(&sem_ids(ns).mutex);
if (cmd == SEM_INFO) {
seminfo.semusz = sem_ids.in_use;
seminfo.semaem = used_sems;
seminfo.semusz = sem_ids(ns).in_use;
seminfo.semaem = ns->used_sems;
} else {
seminfo.semusz = SEMUSZ;
seminfo.semaem = SEMAEM;
}
max_id = sem_ids.max_id;
mutex_unlock(&sem_ids.mutex);
max_id = sem_ids(ns).max_id;
mutex_unlock(&sem_ids(ns).mutex);
if (copy_to_user (arg.__buf, &seminfo, sizeof(struct seminfo)))
return -EFAULT;
return (max_id < 0) ? 0: max_id;
@ -547,12 +597,12 @@ static int semctl_nolock(int semid, int semnum, int cmd, int version, union semu
struct semid64_ds tbuf;
int id;
if(semid >= sem_ids.entries->size)
if(semid >= sem_ids(ns).entries->size)
return -EINVAL;
memset(&tbuf,0,sizeof(tbuf));
sma = sem_lock(semid);
sma = sem_lock(ns, semid);
if(sma == NULL)
return -EINVAL;
@ -564,7 +614,7 @@ static int semctl_nolock(int semid, int semnum, int cmd, int version, union semu
if (err)
goto out_unlock;
id = sem_buildid(semid, sma->sem_perm.seq);
id = sem_buildid(ns, semid, sma->sem_perm.seq);
kernel_to_ipc64_perm(&sma->sem_perm, &tbuf.sem_perm);
tbuf.sem_otime = sma->sem_otime;
@ -584,7 +634,8 @@ out_unlock:
return err;
}
static int semctl_main(int semid, int semnum, int cmd, int version, union semun arg)
static int semctl_main(struct ipc_namespace *ns, int semid, int semnum,
int cmd, int version, union semun arg)
{
struct sem_array *sma;
struct sem* curr;
@ -593,14 +644,14 @@ static int semctl_main(int semid, int semnum, int cmd, int version, union semun
ushort* sem_io = fast_sem_io;
int nsems;
sma = sem_lock(semid);
sma = sem_lock(ns, semid);
if(sma==NULL)
return -EINVAL;
nsems = sma->sem_nsems;
err=-EIDRM;
if (sem_checkid(sma,semid))
if (sem_checkid(ns,sma,semid))
goto out_unlock;
err = -EACCES;
@ -802,7 +853,8 @@ static inline unsigned long copy_semid_from_user(struct sem_setbuf *out, void __
}
}
static int semctl_down(int semid, int semnum, int cmd, int version, union semun arg)
static int semctl_down(struct ipc_namespace *ns, int semid, int semnum,
int cmd, int version, union semun arg)
{
struct sem_array *sma;
int err;
@ -813,11 +865,11 @@ static int semctl_down(int semid, int semnum, int cmd, int version, union semun
if(copy_semid_from_user (&setbuf, arg.buf, version))
return -EFAULT;
}
sma = sem_lock(semid);
sma = sem_lock(ns, semid);
if(sma==NULL)
return -EINVAL;
if (sem_checkid(sma,semid)) {
if (sem_checkid(ns,sma,semid)) {
err=-EIDRM;
goto out_unlock;
}
@ -844,7 +896,7 @@ static int semctl_down(int semid, int semnum, int cmd, int version, union semun
switch(cmd){
case IPC_RMID:
freeary(sma, semid);
freeary(ns, sma, semid);
err = 0;
break;
case IPC_SET:
@ -872,17 +924,19 @@ asmlinkage long sys_semctl (int semid, int semnum, int cmd, union semun arg)
{
int err = -EINVAL;
int version;
struct ipc_namespace *ns;
if (semid < 0)
return -EINVAL;
version = ipc_parse_version(&cmd);
ns = current->nsproxy->ipc_ns;
switch(cmd) {
case IPC_INFO:
case SEM_INFO:
case SEM_STAT:
err = semctl_nolock(semid,semnum,cmd,version,arg);
err = semctl_nolock(ns,semid,semnum,cmd,version,arg);
return err;
case GETALL:
case GETVAL:
@ -892,13 +946,13 @@ asmlinkage long sys_semctl (int semid, int semnum, int cmd, union semun arg)
case IPC_STAT:
case SETVAL:
case SETALL:
err = semctl_main(semid,semnum,cmd,version,arg);
err = semctl_main(ns,semid,semnum,cmd,version,arg);
return err;
case IPC_RMID:
case IPC_SET:
mutex_lock(&sem_ids.mutex);
err = semctl_down(semid,semnum,cmd,version,arg);
mutex_unlock(&sem_ids.mutex);
mutex_lock(&sem_ids(ns).mutex);
err = semctl_down(ns,semid,semnum,cmd,version,arg);
mutex_unlock(&sem_ids(ns).mutex);
return err;
default:
return -EINVAL;
@ -986,7 +1040,7 @@ static struct sem_undo *lookup_undo(struct sem_undo_list *ulp, int semid)
return un;
}
static struct sem_undo *find_undo(int semid)
static struct sem_undo *find_undo(struct ipc_namespace *ns, int semid)
{
struct sem_array *sma;
struct sem_undo_list *ulp;
@ -1005,12 +1059,12 @@ static struct sem_undo *find_undo(int semid)
goto out;
/* no undo structure around - allocate one. */
sma = sem_lock(semid);
sma = sem_lock(ns, semid);
un = ERR_PTR(-EINVAL);
if(sma==NULL)
goto out;
un = ERR_PTR(-EIDRM);
if (sem_checkid(sma,semid)) {
if (sem_checkid(ns,sma,semid)) {
sem_unlock(sma);
goto out;
}
@ -1070,10 +1124,13 @@ asmlinkage long sys_semtimedop(int semid, struct sembuf __user *tsops,
int undos = 0, alter = 0, max;
struct sem_queue queue;
unsigned long jiffies_left = 0;
struct ipc_namespace *ns;
ns = current->nsproxy->ipc_ns;
if (nsops < 1 || semid < 0)
return -EINVAL;
if (nsops > sc_semopm)
if (nsops > ns->sc_semopm)
return -E2BIG;
if(nsops > SEMOPM_FAST) {
sops = kmalloc(sizeof(*sops)*nsops,GFP_KERNEL);
@ -1109,7 +1166,7 @@ asmlinkage long sys_semtimedop(int semid, struct sembuf __user *tsops,
retry_undos:
if (undos) {
un = find_undo(semid);
un = find_undo(ns, semid);
if (IS_ERR(un)) {
error = PTR_ERR(un);
goto out_free;
@ -1117,12 +1174,12 @@ retry_undos:
} else
un = NULL;
sma = sem_lock(semid);
sma = sem_lock(ns, semid);
error=-EINVAL;
if(sma==NULL)
goto out_free;
error = -EIDRM;
if (sem_checkid(sma,semid))
if (sem_checkid(ns,sma,semid))
goto out_unlock_free;
/*
* semid identifies are not unique - find_undo may have
@ -1190,7 +1247,7 @@ retry_undos:
goto out_free;
}
sma = sem_lock(semid);
sma = sem_lock(ns, semid);
if(sma==NULL) {
BUG_ON(queue.prev != NULL);
error = -EIDRM;
@ -1267,6 +1324,7 @@ void exit_sem(struct task_struct *tsk)
{
struct sem_undo_list *undo_list;
struct sem_undo *u, **up;
struct ipc_namespace *ns;
undo_list = tsk->sysvsem.undo_list;
if (!undo_list)
@ -1275,6 +1333,7 @@ void exit_sem(struct task_struct *tsk)
if (!atomic_dec_and_test(&undo_list->refcnt))
return;
ns = tsk->nsproxy->ipc_ns;
/* There's no need to hold the semundo list lock, as current
* is the last task exiting for this undo list.
*/
@ -1288,14 +1347,14 @@ void exit_sem(struct task_struct *tsk)
if(semid == -1)
continue;
sma = sem_lock(semid);
sma = sem_lock(ns, semid);
if (sma == NULL)
continue;
if (u->semid == -1)
goto next_entry;
BUG_ON(sem_checkid(sma,u->semid));
BUG_ON(sem_checkid(ns,sma,u->semid));
/* remove u from the sma->undo list */
for (unp = &sma->undo; (un = *unp); unp = &un->id_next) {