e3222c4ecc
sys_clone() and sys_unshare() both makes copies of nsproxy and its associated namespaces. But they have different code paths. This patch merges all the nsproxy and its associated namespace copy/clone handling (as much as possible). Posted on container list earlier for feedback. - Create a new nsproxy and its associated namespaces and pass it back to caller to attach it to right process. - Changed all copy_*_ns() routines to return a new copy of namespace instead of attaching it to task->nsproxy. - Moved the CAP_SYS_ADMIN checks out of copy_*_ns() routines. - Removed unnessary !ns checks from copy_*_ns() and added BUG_ON() just incase. - Get rid of all individual unshare_*_ns() routines and make use of copy_*_ns() instead. [akpm@osdl.org: cleanups, warning fix] [clg@fr.ibm.com: remove dup_namespaces() declaration] [serue@us.ibm.com: fix CONFIG_IPC_NS=n, clone(CLONE_NEWIPC) retval] [akpm@linux-foundation.org: fix build with CONFIG_SYSVIPC=n] Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com> Signed-off-by: Serge Hallyn <serue@us.ibm.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: <containers@lists.osdl.org> Signed-off-by: Cedric Le Goater <clg@fr.ibm.com> Cc: Oleg Nesterov <oleg@tv-sign.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
45 lines
962 B
C
45 lines
962 B
C
#ifndef _LINUX_PID_NS_H
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#define _LINUX_PID_NS_H
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#include <linux/sched.h>
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#include <linux/mm.h>
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#include <linux/threads.h>
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#include <linux/pid.h>
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#include <linux/nsproxy.h>
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#include <linux/kref.h>
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struct pidmap {
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atomic_t nr_free;
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void *page;
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};
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#define PIDMAP_ENTRIES ((PID_MAX_LIMIT + 8*PAGE_SIZE - 1)/PAGE_SIZE/8)
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struct pid_namespace {
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struct kref kref;
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struct pidmap pidmap[PIDMAP_ENTRIES];
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int last_pid;
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struct task_struct *child_reaper;
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};
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extern struct pid_namespace init_pid_ns;
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static inline void get_pid_ns(struct pid_namespace *ns)
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{
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kref_get(&ns->kref);
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}
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extern struct pid_namespace *copy_pid_ns(int flags, struct pid_namespace *ns);
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extern void free_pid_ns(struct kref *kref);
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static inline void put_pid_ns(struct pid_namespace *ns)
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{
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kref_put(&ns->kref, free_pid_ns);
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}
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static inline struct task_struct *child_reaper(struct task_struct *tsk)
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{
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return init_pid_ns.child_reaper;
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}
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#endif /* _LINUX_PID_NS_H */
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