From 25b21cb2f6d69b0475b134e0a3e8e269137270fa Mon Sep 17 00:00:00 2001 From: Kirill Korotaev Date: Mon, 2 Oct 2006 02:18:19 -0700 Subject: [PATCH] IPC namespace core This patch set allows to unshare IPCs and have a private set of IPC objects (sem, shm, msg) inside namespace. Basically, it is another building block of containers functionality. This patch implements core IPC namespace changes: - ipc_namespace structure - new config option CONFIG_IPC_NS - adds CLONE_NEWIPC flag - unshare support [clg@fr.ibm.com: small fix for unshare of ipc namespace] [akpm@osdl.org: build fix] Signed-off-by: Pavel Emelianov Signed-off-by: Kirill Korotaev Signed-off-by: Cedric Le Goater Cc: "Eric W. Biederman" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/init_task.h | 1 + include/linux/ipc.h | 36 ++++++++++++++++++++++++++++++++++++ include/linux/nsproxy.h | 2 ++ include/linux/sched.h | 1 + init/Kconfig | 9 +++++++++ kernel/fork.c | 22 ++++++++++++++++++---- kernel/nsproxy.c | 41 ++++++++++++++++++++++++++++------------- 7 files changed, 95 insertions(+), 17 deletions(-) diff --git a/include/linux/init_task.h b/include/linux/init_task.h index e08531ec32f..ceecf69dfa3 100644 --- a/include/linux/init_task.h +++ b/include/linux/init_task.h @@ -74,6 +74,7 @@ extern struct nsproxy init_nsproxy; .count = ATOMIC_INIT(1), \ .nslock = SPIN_LOCK_UNLOCKED, \ .uts_ns = &init_uts_ns, \ + .ipc_ns = &init_ipc_ns, \ .namespace = NULL, \ } diff --git a/include/linux/ipc.h b/include/linux/ipc.h index b291189737e..36027b10f28 100644 --- a/include/linux/ipc.h +++ b/include/linux/ipc.h @@ -2,6 +2,7 @@ #define _LINUX_IPC_H #include +#include #define IPC_PRIVATE ((__kernel_key_t) 0) @@ -68,6 +69,41 @@ struct kern_ipc_perm void *security; }; +struct ipc_ids; +struct ipc_namespace { + struct kref kref; + struct ipc_ids *ids[3]; + + int sem_ctls[4]; + int used_sems; + + int msg_ctlmax; + int msg_ctlmnb; + int msg_ctlmni; + + size_t shm_ctlmax; + size_t shm_ctlall; + int shm_ctlmni; + int shm_tot; +}; + +extern struct ipc_namespace init_ipc_ns; +extern void free_ipc_ns(struct kref *kref); +extern int copy_ipcs(unsigned long flags, struct task_struct *tsk); +extern int unshare_ipcs(unsigned long flags, struct ipc_namespace **ns); + +static inline struct ipc_namespace *get_ipc_ns(struct ipc_namespace *ns) +{ + if (ns) + kref_get(&ns->kref); + return ns; +} + +static inline void put_ipc_ns(struct ipc_namespace *ns) +{ + kref_put(&ns->kref, free_ipc_ns); +} + #endif /* __KERNEL__ */ #endif /* _LINUX_IPC_H */ diff --git a/include/linux/nsproxy.h b/include/linux/nsproxy.h index 9c2e0ad508d..f6baecdeecd 100644 --- a/include/linux/nsproxy.h +++ b/include/linux/nsproxy.h @@ -6,6 +6,7 @@ struct namespace; struct uts_namespace; +struct ipc_namespace; /* * A structure to contain pointers to all per-process @@ -23,6 +24,7 @@ struct nsproxy { atomic_t count; spinlock_t nslock; struct uts_namespace *uts_ns; + struct ipc_namespace *ipc_ns; struct namespace *namespace; }; extern struct nsproxy init_nsproxy; diff --git a/include/linux/sched.h b/include/linux/sched.h index a973e701231..9ba959e3426 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -25,6 +25,7 @@ #define CLONE_CHILD_SETTID 0x01000000 /* set the TID in the child */ #define CLONE_STOPPED 0x02000000 /* Start in stopped state */ #define CLONE_NEWUTS 0x04000000 /* New utsname group? */ +#define CLONE_NEWIPC 0x08000000 /* New ipcs */ /* * Scheduling policies diff --git a/init/Kconfig b/init/Kconfig index b0ea9755447..10382931eea 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -115,6 +115,15 @@ config SYSVIPC section 6.4 of the Linux Programmer's Guide, available from . +config IPC_NS + bool "IPC Namespaces" + depends on SYSVIPC + default n + help + Support ipc namespaces. This allows containers, i.e. virtual + environments, to use ipc namespaces to provide different ipc + objects for different servers. If unsure, say N. + config POSIX_MQUEUE bool "POSIX Message Queues" depends on NET && EXPERIMENTAL diff --git a/kernel/fork.c b/kernel/fork.c index 208dd99f13b..d6cc5655850 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1608,13 +1608,15 @@ asmlinkage long sys_unshare(unsigned long unshare_flags) struct sem_undo_list *new_ulist = NULL; struct nsproxy *new_nsproxy = NULL, *old_nsproxy = NULL; struct uts_namespace *uts, *new_uts = NULL; + struct ipc_namespace *ipc, *new_ipc = NULL; check_unshare_flags(&unshare_flags); /* Return -EINVAL for all unsupported flags */ err = -EINVAL; if (unshare_flags & ~(CLONE_THREAD|CLONE_FS|CLONE_NEWNS|CLONE_SIGHAND| - CLONE_VM|CLONE_FILES|CLONE_SYSVSEM|CLONE_NEWUTS)) + CLONE_VM|CLONE_FILES|CLONE_SYSVSEM| + CLONE_NEWUTS|CLONE_NEWIPC)) goto bad_unshare_out; if ((err = unshare_thread(unshare_flags))) @@ -1633,18 +1635,20 @@ asmlinkage long sys_unshare(unsigned long unshare_flags) goto bad_unshare_cleanup_fd; if ((err = unshare_utsname(unshare_flags, &new_uts))) goto bad_unshare_cleanup_semundo; + if ((err = unshare_ipcs(unshare_flags, &new_ipc))) + goto bad_unshare_cleanup_uts; - if (new_ns || new_uts) { + if (new_ns || new_uts || new_ipc) { old_nsproxy = current->nsproxy; new_nsproxy = dup_namespaces(old_nsproxy); if (!new_nsproxy) { err = -ENOMEM; - goto bad_unshare_cleanup_uts; + goto bad_unshare_cleanup_ipc; } } if (new_fs || new_ns || new_sigh || new_mm || new_fd || new_ulist || - new_uts) { + new_uts || new_ipc) { task_lock(current); @@ -1692,12 +1696,22 @@ asmlinkage long sys_unshare(unsigned long unshare_flags) new_uts = uts; } + if (new_ipc) { + ipc = current->nsproxy->ipc_ns; + current->nsproxy->ipc_ns = new_ipc; + new_ipc = ipc; + } + task_unlock(current); } if (new_nsproxy) put_nsproxy(new_nsproxy); +bad_unshare_cleanup_ipc: + if (new_ipc) + put_ipc_ns(new_ipc); + bad_unshare_cleanup_uts: if (new_uts) put_uts_ns(new_uts); diff --git a/kernel/nsproxy.c b/kernel/nsproxy.c index 8246813335c..8d6c852dc51 100644 --- a/kernel/nsproxy.c +++ b/kernel/nsproxy.c @@ -7,6 +7,10 @@ * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation, version 2 of the * License. + * + * Jun 2006 - namespaces support + * OpenVZ, SWsoft Inc. + * Pavel Emelianov */ #include @@ -62,6 +66,8 @@ struct nsproxy *dup_namespaces(struct nsproxy *orig) get_namespace(ns->namespace); if (ns->uts_ns) get_uts_ns(ns->uts_ns); + if (ns->ipc_ns) + get_ipc_ns(ns->ipc_ns); } return ns; @@ -82,7 +88,7 @@ int copy_namespaces(int flags, struct task_struct *tsk) get_nsproxy(old_ns); - if (!(flags & (CLONE_NEWNS | CLONE_NEWUTS))) + if (!(flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC))) return 0; new_ns = clone_namespaces(old_ns); @@ -94,24 +100,31 @@ int copy_namespaces(int flags, struct task_struct *tsk) tsk->nsproxy = new_ns; err = copy_namespace(flags, tsk); - if (err) { - tsk->nsproxy = old_ns; - put_nsproxy(new_ns); - goto out; - } + if (err) + goto out_ns; err = copy_utsname(flags, tsk); - if (err) { - if (new_ns->namespace) - put_namespace(new_ns->namespace); - tsk->nsproxy = old_ns; - put_nsproxy(new_ns); - goto out; - } + if (err) + goto out_uts; + + err = copy_ipcs(flags, tsk); + if (err) + goto out_ipc; out: put_nsproxy(old_ns); return err; + +out_ipc: + if (new_ns->uts_ns) + put_uts_ns(new_ns->uts_ns); +out_uts: + if (new_ns->namespace) + put_namespace(new_ns->namespace); +out_ns: + tsk->nsproxy = old_ns; + put_nsproxy(new_ns); + goto out; } void free_nsproxy(struct nsproxy *ns) @@ -120,5 +133,7 @@ void free_nsproxy(struct nsproxy *ns) put_namespace(ns->namespace); if (ns->uts_ns) put_uts_ns(ns->uts_ns); + if (ns->ipc_ns) + put_ipc_ns(ns->ipc_ns); kfree(ns); } -- cgit v1.2.3