diff options
Diffstat (limited to 'ipc/namespace.c')
| -rw-r--r-- | ipc/namespace.c | 79 |
1 files changed, 72 insertions, 7 deletions
diff --git a/ipc/namespace.c b/ipc/namespace.c index a1094ff0bef..59451c1e214 100644 --- a/ipc/namespace.c +++ b/ipc/namespace.c @@ -11,10 +11,13 @@ #include <linux/slab.h> #include <linux/fs.h> #include <linux/mount.h> +#include <linux/user_namespace.h> +#include <linux/proc_ns.h> #include "util.h" -static struct ipc_namespace *create_ipc_ns(void) +static struct ipc_namespace *create_ipc_ns(struct user_namespace *user_ns, + struct ipc_namespace *old_ns) { struct ipc_namespace *ns; int err; @@ -23,9 +26,16 @@ static struct ipc_namespace *create_ipc_ns(void) if (ns == NULL) return ERR_PTR(-ENOMEM); + err = proc_alloc_inum(&ns->proc_inum); + if (err) { + kfree(ns); + return ERR_PTR(err); + } + atomic_set(&ns->count, 1); err = mq_init_ns(ns); if (err) { + proc_free_inum(ns->proc_inum); kfree(ns); return ERR_PTR(err); } @@ -43,14 +53,17 @@ static struct ipc_namespace *create_ipc_ns(void) ipcns_notify(IPCNS_CREATED); register_ipcns_notifier(ns); + ns->user_ns = get_user_ns(user_ns); + return ns; } -struct ipc_namespace *copy_ipcs(unsigned long flags, struct ipc_namespace *ns) +struct ipc_namespace *copy_ipcs(unsigned long flags, + struct user_namespace *user_ns, struct ipc_namespace *ns) { if (!(flags & CLONE_NEWIPC)) return get_ipc_ns(ns); - return create_ipc_ns(); + return create_ipc_ns(user_ns, ns); } /* @@ -68,7 +81,7 @@ void free_ipcs(struct ipc_namespace *ns, struct ipc_ids *ids, int next_id; int total, in_use; - down_write(&ids->rw_mutex); + down_write(&ids->rwsem); in_use = ids->in_use; @@ -76,11 +89,12 @@ void free_ipcs(struct ipc_namespace *ns, struct ipc_ids *ids, perm = idr_find(&ids->ipcs_idr, next_id); if (perm == NULL) continue; - ipc_lock_by_ptr(perm); + rcu_read_lock(); + ipc_lock_object(perm); free(ns, perm); total++; } - up_write(&ids->rw_mutex); + up_write(&ids->rwsem); } static void free_ipc_ns(struct ipc_namespace *ns) @@ -97,7 +111,6 @@ static void free_ipc_ns(struct ipc_namespace *ns) sem_exit_ns(ns); msg_exit_ns(ns); shm_exit_ns(ns); - kfree(ns); atomic_dec(&nr_ipc_ns); /* @@ -105,6 +118,9 @@ static void free_ipc_ns(struct ipc_namespace *ns) * order to have a correct value when recomputing msgmni. */ ipcns_notify(IPCNS_REMOVED); + put_user_ns(ns->user_ns); + proc_free_inum(ns->proc_inum); + kfree(ns); } /* @@ -132,3 +148,52 @@ void put_ipc_ns(struct ipc_namespace *ns) free_ipc_ns(ns); } } + +static void *ipcns_get(struct task_struct *task) +{ + struct ipc_namespace *ns = NULL; + struct nsproxy *nsproxy; + + rcu_read_lock(); + nsproxy = task_nsproxy(task); + if (nsproxy) + ns = get_ipc_ns(nsproxy->ipc_ns); + rcu_read_unlock(); + + return ns; +} + +static void ipcns_put(void *ns) +{ + return put_ipc_ns(ns); +} + +static int ipcns_install(struct nsproxy *nsproxy, void *new) +{ + struct ipc_namespace *ns = new; + if (!ns_capable(ns->user_ns, CAP_SYS_ADMIN) || + !ns_capable(current_user_ns(), CAP_SYS_ADMIN)) + return -EPERM; + + /* Ditch state from the old ipc namespace */ + exit_sem(current); + put_ipc_ns(nsproxy->ipc_ns); + nsproxy->ipc_ns = get_ipc_ns(ns); + return 0; +} + +static unsigned int ipcns_inum(void *vp) +{ + struct ipc_namespace *ns = vp; + + return ns->proc_inum; +} + +const struct proc_ns_operations ipcns_operations = { + .name = "ipc", + .type = CLONE_NEWIPC, + .get = ipcns_get, + .put = ipcns_put, + .install = ipcns_install, + .inum = ipcns_inum, +}; |