diff options
| -rw-r--r-- | include/linux/init_task.h | 2 | ||||
| -rw-r--r-- | include/linux/nsproxy.h | 2 | ||||
| -rw-r--r-- | include/linux/sched.h | 1 | ||||
| -rw-r--r-- | include/linux/utsname.h | 40 | ||||
| -rw-r--r-- | init/Kconfig | 8 | ||||
| -rw-r--r-- | init/version.c | 23 | ||||
| -rw-r--r-- | kernel/Makefile | 1 | ||||
| -rw-r--r-- | kernel/nsproxy.c | 14 | ||||
| -rw-r--r-- | kernel/utsname.c | 42 |
9 files changed, 121 insertions, 12 deletions
diff --git a/include/linux/init_task.h b/include/linux/init_task.h index 4865348ca8bd..e08531ec32f0 100644 --- a/include/linux/init_task.h +++ b/include/linux/init_task.h @@ -4,6 +4,7 @@ #include <linux/file.h> #include <linux/rcupdate.h> #include <linux/irqflags.h> +#include <linux/utsname.h> #include <linux/lockdep.h> #define INIT_FDTABLE \ @@ -72,6 +73,7 @@ extern struct nsproxy init_nsproxy; #define INIT_NSPROXY(nsproxy) { \ .count = ATOMIC_INIT(1), \ .nslock = SPIN_LOCK_UNLOCKED, \ + .uts_ns = &init_uts_ns, \ .namespace = NULL, \ } diff --git a/include/linux/nsproxy.h b/include/linux/nsproxy.h index 7ebe66670c59..9c2e0ad508db 100644 --- a/include/linux/nsproxy.h +++ b/include/linux/nsproxy.h @@ -5,6 +5,7 @@ #include <linux/sched.h> struct namespace; +struct uts_namespace; /* * A structure to contain pointers to all per-process @@ -21,6 +22,7 @@ struct namespace; struct nsproxy { atomic_t count; spinlock_t nslock; + struct uts_namespace *uts_ns; struct namespace *namespace; }; extern struct nsproxy init_nsproxy; diff --git a/include/linux/sched.h b/include/linux/sched.h index 670b89a20070..46d6f5be72f2 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -753,6 +753,7 @@ static inline void prefetch_stack(struct task_struct *t) { } struct audit_context; /* See audit.c */ struct mempolicy; struct pipe_inode_info; +struct uts_namespace; enum sleep_type { SLEEP_NORMAL, diff --git a/include/linux/utsname.h b/include/linux/utsname.h index 77e97a5755d9..afa54e1542b3 100644 --- a/include/linux/utsname.h +++ b/include/linux/utsname.h @@ -1,6 +1,11 @@ #ifndef _LINUX_UTSNAME_H #define _LINUX_UTSNAME_H +#include <linux/sched.h> +#include <linux/kref.h> +#include <linux/nsproxy.h> +#include <asm/atomic.h> + #define __OLD_UTS_LEN 8 struct oldold_utsname { @@ -30,17 +35,46 @@ struct new_utsname { char domainname[65]; }; -extern struct new_utsname system_utsname; +struct uts_namespace { + struct kref kref; + struct new_utsname name; +}; +extern struct uts_namespace init_uts_ns; + +static inline void get_uts_ns(struct uts_namespace *ns) +{ + kref_get(&ns->kref); +} + +#ifdef CONFIG_UTS_NS +extern int copy_utsname(int flags, struct task_struct *tsk); +extern void free_uts_ns(struct kref *kref); + +static inline void put_uts_ns(struct uts_namespace *ns) +{ + kref_put(&ns->kref, free_uts_ns); +} +#else +static inline int copy_utsname(int flags, struct task_struct *tsk) +{ + return 0; +} +static inline void put_uts_ns(struct uts_namespace *ns) +{ +} +#endif static inline struct new_utsname *utsname(void) { - return &system_utsname; + return ¤t->nsproxy->uts_ns->name; } static inline struct new_utsname *init_utsname(void) { - return &system_utsname; + return &init_uts_ns.name; } +#define system_utsname init_uts_ns.name + extern struct rw_semaphore uts_sem; #endif diff --git a/init/Kconfig b/init/Kconfig index f7a04d0daf07..b0ea97554473 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -182,6 +182,14 @@ config TASK_DELAY_ACCT Say N if unsure. +config UTS_NS + bool "UTS Namespaces" + default n + help + Support uts namespaces. This allows containers, i.e. + vservers, to use uts namespaces to provide different + uts info for different servers. If unsure, say N. + config AUDIT bool "Auditing support" depends on NET diff --git a/init/version.c b/init/version.c index e290802c6bd2..8f28344d9c70 100644 --- a/init/version.c +++ b/init/version.c @@ -12,22 +12,27 @@ #include <linux/utsname.h> #include <linux/utsrelease.h> #include <linux/version.h> +#include <linux/sched.h> #define version(a) Version_ ## a #define version_string(a) version(a) int version_string(LINUX_VERSION_CODE); -struct new_utsname system_utsname = { - .sysname = UTS_SYSNAME, - .nodename = UTS_NODENAME, - .release = UTS_RELEASE, - .version = UTS_VERSION, - .machine = UTS_MACHINE, - .domainname = UTS_DOMAINNAME, +struct uts_namespace init_uts_ns = { + .kref = { + .refcount = ATOMIC_INIT(2), + }, + .name = { + .sysname = UTS_SYSNAME, + .nodename = UTS_NODENAME, + .release = UTS_RELEASE, + .version = UTS_VERSION, + .machine = UTS_MACHINE, + .domainname = UTS_DOMAINNAME, + }, }; - -EXPORT_SYMBOL(system_utsname); +EXPORT_SYMBOL_GPL(init_uts_ns); const char linux_banner[] = "Linux version " UTS_RELEASE " (" LINUX_COMPILE_BY "@" diff --git a/kernel/Makefile b/kernel/Makefile index 6ec53009b866..d948ca12acf0 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -48,6 +48,7 @@ obj-$(CONFIG_GENERIC_HARDIRQS) += irq/ obj-$(CONFIG_SECCOMP) += seccomp.o obj-$(CONFIG_RCU_TORTURE_TEST) += rcutorture.o obj-$(CONFIG_RELAY) += relay.o +obj-$(CONFIG_UTS_NS) += utsname.o obj-$(CONFIG_TASK_DELAY_ACCT) += delayacct.o obj-$(CONFIG_TASKSTATS) += taskstats.o tsacct.o diff --git a/kernel/nsproxy.c b/kernel/nsproxy.c index e10385c17f73..47c19280c55b 100644 --- a/kernel/nsproxy.c +++ b/kernel/nsproxy.c @@ -14,6 +14,7 @@ #include <linux/nsproxy.h> #include <linux/init_task.h> #include <linux/namespace.h> +#include <linux/utsname.h> struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy); @@ -59,6 +60,8 @@ struct nsproxy *dup_namespaces(struct nsproxy *orig) if (ns) { if (ns->namespace) get_namespace(ns->namespace); + if (ns->uts_ns) + get_uts_ns(ns->uts_ns); } return ns; @@ -97,6 +100,15 @@ int copy_namespaces(int flags, struct task_struct *tsk) goto out; } + 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; + } + out: put_nsproxy(old_ns); return err; @@ -106,5 +118,7 @@ void free_nsproxy(struct nsproxy *ns) { if (ns->namespace) put_namespace(ns->namespace); + if (ns->uts_ns) + put_uts_ns(ns->uts_ns); kfree(ns); } diff --git a/kernel/utsname.c b/kernel/utsname.c new file mode 100644 index 000000000000..1824384ecfa3 --- /dev/null +++ b/kernel/utsname.c @@ -0,0 +1,42 @@ +/* + * Copyright (C) 2004 IBM Corporation + * + * Author: Serge Hallyn <serue@us.ibm.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation, version 2 of the + * License. + */ + +#include <linux/module.h> +#include <linux/uts.h> +#include <linux/utsname.h> +#include <linux/version.h> + +/* + * Copy task tsk's utsname namespace, or clone it if flags + * specifies CLONE_NEWUTS. In latter case, changes to the + * utsname of this process won't be seen by parent, and vice + * versa. + */ +int copy_utsname(int flags, struct task_struct *tsk) +{ + struct uts_namespace *old_ns = tsk->nsproxy->uts_ns; + int err = 0; + + if (!old_ns) + return 0; + + get_uts_ns(old_ns); + + return err; +} + +void free_uts_ns(struct kref *kref) +{ + struct uts_namespace *ns; + + ns = container_of(kref, struct uts_namespace, kref); + kfree(ns); +} |