diff options
Diffstat (limited to 'ipc/util.c')
| -rw-r--r-- | ipc/util.c | 132 |
1 files changed, 122 insertions, 10 deletions
diff --git a/ipc/util.c b/ipc/util.c index 67b6d178db6e..42479e4eec59 100644 --- a/ipc/util.c +++ b/ipc/util.c @@ -12,6 +12,9 @@ * Mingming Cao <cmm@us.ibm.com> * Mar 2006 - support for audit of ipc object properties * Dustin Kirkland <dustin.kirkland@us.ibm.com> + * Jun 2006 - namespaces ssupport + * OpenVZ, SWsoft Inc. + * Pavel Emelianov <xemul@openvz.org> */ #include <linux/mm.h> @@ -29,6 +32,7 @@ #include <linux/seq_file.h> #include <linux/proc_fs.h> #include <linux/audit.h> +#include <linux/nsproxy.h> #include <asm/unistd.h> @@ -37,10 +41,111 @@ 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); + 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); + kfree(ns); +} +#endif + /** * ipc_init - initialise IPC subsystem * @@ -67,7 +172,7 @@ __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; @@ -110,8 +215,7 @@ 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; @@ -635,6 +739,9 @@ 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) @@ -644,8 +751,8 @@ 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; } @@ -664,12 +771,15 @@ 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(). */ - mutex_lock(&iface->ids->mutex); + mutex_lock(&ids->mutex); /* pos < 0 is invalid */ if (*pos < 0) @@ -680,8 +790,8 @@ 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; } @@ -693,13 +803,15 @@ 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() */ - mutex_unlock(&iface->ids->mutex); + mutex_unlock(&ids->mutex); } static int sysvipc_proc_show(struct seq_file *s, void *it) |
