X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=ipc%2Futil.c;h=37e59a988ad1cf1016a9a88b9e45bd8043ae5de5;hb=97bf2856c6014879bd04983a3e9dfcdac1e7fe85;hp=3d4b5c1d3312af6b9174c4abca98668bf661ed0d;hpb=76828883507a47dae78837ab5dec5a5b4513c667;p=linux-2.6.git diff --git a/ipc/util.c b/ipc/util.c index 3d4b5c1d3..37e59a988 100644 --- a/ipc/util.c +++ b/ipc/util.c @@ -10,9 +10,13 @@ * Manfred Spraul * Oct 2002 - One lock per IPC id. RCU ipc_free for lock-free grow_ary(). * Mingming Cao + * Mar 2006 - support for audit of ipc object properties + * Dustin Kirkland + * Jun 2006 - namespaces ssupport + * OpenVZ, SWsoft Inc. + * Pavel Emelianov */ -#include #include #include #include @@ -27,6 +31,10 @@ #include #include #include +#include +#include +#include +#include #include @@ -35,10 +43,113 @@ struct ipc_proc_iface { const char *path; const char *header; - struct ipc_ids *ids; + int ids; int (*show)(struct seq_file *, void *); }; +struct ipc_namespace init_ipc_ns = { + .kref = { + .refcount = ATOMIC_INIT(2), + }, +}; + +#ifdef CONFIG_IPC_NS +static struct ipc_namespace *clone_ipc_ns(struct ipc_namespace *old_ns) +{ + int err; + struct ipc_namespace *ns; + + err = -ENOMEM; + ns = kmalloc(sizeof(struct ipc_namespace), GFP_KERNEL); + if (ns == NULL) + goto err_mem; + + err = sem_init_ns(ns); + if (err) + goto err_sem; + err = msg_init_ns(ns); + if (err) + goto err_msg; + err = shm_init_ns(ns); + if (err) + goto err_shm; + + kref_init(&ns->kref); + atomic_inc(&vs_global_ipc_ns); + return ns; + +err_shm: + msg_exit_ns(ns); +err_msg: + sem_exit_ns(ns); +err_sem: + kfree(ns); +err_mem: + return ERR_PTR(err); +} + +int unshare_ipcs(unsigned long unshare_flags, struct ipc_namespace **new_ipc) +{ + struct ipc_namespace *new; + + if (unshare_flags & CLONE_NEWIPC) { + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + new = clone_ipc_ns(current->nsproxy->ipc_ns); + if (IS_ERR(new)) + return PTR_ERR(new); + + *new_ipc = new; + } + + return 0; +} + +int copy_ipcs(unsigned long flags, struct task_struct *tsk) +{ + struct ipc_namespace *old_ns = tsk->nsproxy->ipc_ns; + struct ipc_namespace *new_ns; + int err = 0; + + if (!old_ns) + return 0; + + get_ipc_ns(old_ns); + + if (!(flags & CLONE_NEWIPC)) + return 0; + + if (!capable(CAP_SYS_ADMIN)) { + err = -EPERM; + goto out; + } + + new_ns = clone_ipc_ns(old_ns); + if (!new_ns) { + err = -ENOMEM; + goto out; + } + + tsk->nsproxy->ipc_ns = new_ns; +out: + put_ipc_ns(old_ns); + return err; +} + +void free_ipc_ns(struct kref *kref) +{ + struct ipc_namespace *ns; + + ns = container_of(kref, struct ipc_namespace, kref); + sem_exit_ns(ns); + msg_exit_ns(ns); + shm_exit_ns(ns); + atomic_dec(&vs_global_ipc_ns); + kfree(ns); +} +#endif + /** * ipc_init - initialise IPC subsystem * @@ -65,10 +176,11 @@ __initcall(ipc_init); * array itself. */ -void __init ipc_init_ids(struct ipc_ids* ids, int size) +void __ipc_init ipc_init_ids(struct ipc_ids* ids, int size) { int i; - sema_init(&ids->sem,1); + + mutex_init(&ids->mutex); if(size > IPCMNI) size = IPCMNI; @@ -107,8 +219,7 @@ static struct file_operations sysvipc_proc_fops; * @show: show routine. */ void __init ipc_init_proc_interface(const char *path, const char *header, - struct ipc_ids *ids, - int (*show)(struct seq_file *, void *)) + int ids, int (*show)(struct seq_file *, void *)) { struct proc_dir_entry *pde; struct ipc_proc_iface *iface; @@ -138,7 +249,7 @@ void __init ipc_init_proc_interface(const char *path, const char *header, * @ids: Identifier set * @key: The key to find * - * Requires ipc_ids.sem locked. + * Requires ipc_ids.mutex locked. * Returns the identifier if found or -1 if not. */ @@ -150,13 +261,11 @@ int ipc_findkey(struct ipc_ids* ids, key_t key) /* * rcu_dereference() is not needed here - * since ipc_ids.sem is held + * since ipc_ids.mutex is held */ for (id = 0; id <= max_id; id++) { p = ids->entries->p[id]; - if (p==NULL) - continue; - if (!vx_check(p->xid, VX_IDENT)) + if(p==NULL) continue; if (key == p->key) return id; @@ -165,7 +274,7 @@ int ipc_findkey(struct ipc_ids* ids, key_t key) } /* - * Requires ipc_ids.sem locked + * Requires ipc_ids.mutex locked */ static int grow_ary(struct ipc_ids* ids, int newsize) { @@ -196,7 +305,7 @@ static int grow_ary(struct ipc_ids* ids, int newsize) */ rcu_assign_pointer(ids->entries, new); - ipc_rcu_putref(old); + __ipc_fini_ids(ids, old); return newsize; } @@ -211,7 +320,7 @@ static int grow_ary(struct ipc_ids* ids, int newsize) * is returned. The list is returned in a locked state on success. * On failure the list is not locked and -1 is returned. * - * Called with ipc_ids.sem held. + * Called with ipc_ids.mutex held. */ int ipc_addid(struct ipc_ids* ids, struct kern_ipc_perm* new, int size) @@ -222,7 +331,7 @@ int ipc_addid(struct ipc_ids* ids, struct kern_ipc_perm* new, int size) /* * rcu_dereference()() is not needed here since - * ipc_ids.sem is held + * ipc_ids.mutex is held */ for (id = 0; id < size; id++) { if(ids->entries->p[id] == NULL) @@ -258,7 +367,7 @@ found: * fed an invalid identifier. The entry is removed and internal * variables recomputed. The object associated with the identifier * is returned. - * ipc_ids.sem and the spinlock for this ID is hold before this function + * ipc_ids.mutex and the spinlock for this ID is hold before this function * is called, and remain locked on the exit. */ @@ -266,17 +375,15 @@ struct kern_ipc_perm* ipc_rmid(struct ipc_ids* ids, int id) { struct kern_ipc_perm* p; int lid = id % SEQ_MULTIPLIER; - if(lid >= ids->entries->size) - BUG(); + BUG_ON(lid >= ids->entries->size); /* * do not need a rcu_dereference()() here to force ordering - * on Alpha, since the ipc_ids.sem is held. + * on Alpha, since the ipc_ids.mutex is held. */ p = ids->entries->p[lid]; ids->entries->p[lid] = NULL; - if(p==NULL) - BUG(); + BUG_ON(p==NULL); ids->in_use--; if (lid == ids->max_id) { @@ -411,6 +518,11 @@ void ipc_rcu_getref(void *ptr) container_of(ptr, struct ipc_rcu_hdr, data)->refcount++; } +static void ipc_do_vfree(struct work_struct *work) +{ + vfree(container_of(work, struct ipc_rcu_sched, work)); +} + /** * ipc_schedule_free - free ipc + rcu space * @head: RCU callback structure for queued work @@ -425,7 +537,7 @@ static void ipc_schedule_free(struct rcu_head *head) struct ipc_rcu_sched *sched = container_of(&(grace->data[0]), struct ipc_rcu_sched, data[0]); - INIT_WORK(&sched->work, vfree, sched); + INIT_WORK(&sched->work, ipc_do_vfree); schedule_work(&sched->work); } @@ -467,10 +579,10 @@ void ipc_rcu_putref(void *ptr) int ipcperms (struct kern_ipc_perm *ipcp, short flag) { /* flag will most probably be 0 or S_...UGO from */ - int requested_mode, granted_mode; + int requested_mode, granted_mode, err; - if (!vx_check(ipcp->xid, VX_ADMIN|VX_IDENT)) /* maybe just VX_IDENT? */ - return -1; + if (unlikely((err = audit_ipc_obj(ipcp)))) + return err; requested_mode = (flag >> 6) | (flag >> 3) | flag; granted_mode = ipcp->mode; if (current->euid == ipcp->cuid || current->euid == ipcp->uid) @@ -533,13 +645,13 @@ void ipc64_perm_to_ipc_perm (struct ipc64_perm *in, struct ipc_perm *out) /* * So far only shm_get_stat() calls ipc_get() via shm_get(), so ipc_get() - * is called with shm_ids.sem locked. Since grow_ary() is also called with - * shm_ids.sem down(for Shared Memory), there is no need to add read + * is called with shm_ids.mutex locked. Since grow_ary() is also called with + * shm_ids.mutex down(for Shared Memory), there is no need to add read * barriers here to gurantee the writes in grow_ary() are seen in order * here (for Alpha). * - * However ipc_get() itself does not necessary require ipc_ids.sem down. So - * if in the future ipc_get() is used by other places without ipc_ids.sem + * However ipc_get() itself does not necessary require ipc_ids.mutex down. So + * if in the future ipc_get() is used by other places without ipc_ids.mutex * down, then ipc_get() needs read memery barriers as ipc_lock() does. */ struct kern_ipc_perm* ipc_get(struct ipc_ids* ids, int id) @@ -636,6 +748,9 @@ static void *sysvipc_proc_next(struct seq_file *s, void *it, loff_t *pos) struct ipc_proc_iface *iface = s->private; struct kern_ipc_perm *ipc = it; loff_t p; + struct ipc_ids *ids; + + ids = current->nsproxy->ipc_ns->ids[iface->ids]; /* If we had an ipc id locked before, unlock it */ if (ipc && ipc != SEQ_START_TOKEN) @@ -645,8 +760,8 @@ static void *sysvipc_proc_next(struct seq_file *s, void *it, loff_t *pos) * p = *pos - 1 (because id 0 starts at position 1) * + 1 (because we increment the position by one) */ - for (p = *pos; p <= iface->ids->max_id; p++) { - if ((ipc = ipc_lock(iface->ids, p)) != NULL) { + for (p = *pos; p <= ids->max_id; p++) { + if ((ipc = ipc_lock(ids, p)) != NULL) { *pos = p + 1; return ipc; } @@ -665,12 +780,15 @@ static void *sysvipc_proc_start(struct seq_file *s, loff_t *pos) struct ipc_proc_iface *iface = s->private; struct kern_ipc_perm *ipc; loff_t p; + struct ipc_ids *ids; + + ids = current->nsproxy->ipc_ns->ids[iface->ids]; /* * Take the lock - this will be released by the corresponding * call to stop(). */ - down(&iface->ids->sem); + mutex_lock(&ids->mutex); /* pos < 0 is invalid */ if (*pos < 0) @@ -681,8 +799,8 @@ static void *sysvipc_proc_start(struct seq_file *s, loff_t *pos) return SEQ_START_TOKEN; /* Find the (pos-1)th ipc */ - for (p = *pos - 1; p <= iface->ids->max_id; p++) { - if ((ipc = ipc_lock(iface->ids, p)) != NULL) { + for (p = *pos - 1; p <= ids->max_id; p++) { + if ((ipc = ipc_lock(ids, p)) != NULL) { *pos = p + 1; return ipc; } @@ -694,13 +812,15 @@ static void sysvipc_proc_stop(struct seq_file *s, void *it) { struct kern_ipc_perm *ipc = it; struct ipc_proc_iface *iface = s->private; + struct ipc_ids *ids; /* If we had a locked segment, release it */ if (ipc && ipc != SEQ_START_TOKEN) ipc_unlock(ipc); + ids = current->nsproxy->ipc_ns->ids[iface->ids]; /* Release the lock we took in start() */ - up(&iface->ids->sem); + mutex_unlock(&ids->mutex); } static int sysvipc_proc_show(struct seq_file *s, void *it)