diff options
Diffstat (limited to 'ipc/sem.c')
-rw-r--r-- | ipc/sem.c | 201 |
1 files changed, 130 insertions, 71 deletions
@@ -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(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) -#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; +static struct ipc_ids init_sem_ids; -static int newary (key_t, int, int); -static void freeary (struct sem_array *sma, int id); +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 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); -static int used_sems; + 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; + + ns = current->nsproxy->ipc_ns; - if (nsems < 0 || nsems > sc_semmsl) + 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) { |