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c7e12b8389
Fix two issuses related to ipc_ids->entries freeing. 1. When freeing ipc namespace we need to free entries allocated with ipc_init_ids(). 2. When removing old entries in grow_ary() ipc_rcu_putref() may be called on entries set to &ids->nullentry earlier in ipc_init_ids(). This is almost impossible without namespaces, but with them this situation becomes possible. Found during OpenVZ testing after obvious leaks in beancounters. Signed-off-by: Pavel Emelianov <xemul@openvz.org> Cc: Kirill Korotaev <dev@openvz.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
120 lines
3.3 KiB
C
120 lines
3.3 KiB
C
/*
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* linux/ipc/util.h
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* Copyright (C) 1999 Christoph Rohland
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*
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* ipc helper functions (c) 1999 Manfred Spraul <manfred@colorfullife.com>
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* namespaces support. 2006 OpenVZ, SWsoft Inc.
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* Pavel Emelianov <xemul@openvz.org>
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*/
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#ifndef _IPC_UTIL_H
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#define _IPC_UTIL_H
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#define USHRT_MAX 0xffff
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#define SEQ_MULTIPLIER (IPCMNI)
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void sem_init (void);
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void msg_init (void);
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void shm_init (void);
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int sem_init_ns(struct ipc_namespace *ns);
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int msg_init_ns(struct ipc_namespace *ns);
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int shm_init_ns(struct ipc_namespace *ns);
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void sem_exit_ns(struct ipc_namespace *ns);
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void msg_exit_ns(struct ipc_namespace *ns);
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void shm_exit_ns(struct ipc_namespace *ns);
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struct ipc_id_ary {
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int size;
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struct kern_ipc_perm *p[0];
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};
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struct ipc_ids {
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int in_use;
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int max_id;
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unsigned short seq;
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unsigned short seq_max;
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struct mutex mutex;
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struct ipc_id_ary nullentry;
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struct ipc_id_ary* entries;
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};
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struct seq_file;
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#ifdef CONFIG_IPC_NS
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#define __ipc_init
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#else
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#define __ipc_init __init
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#endif
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void __ipc_init ipc_init_ids(struct ipc_ids *ids, int size);
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#ifdef CONFIG_PROC_FS
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void __init ipc_init_proc_interface(const char *path, const char *header,
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int ids, int (*show)(struct seq_file *, void *));
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#else
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#define ipc_init_proc_interface(path, header, ids, show) do {} while (0)
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#endif
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#define IPC_SEM_IDS 0
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#define IPC_MSG_IDS 1
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#define IPC_SHM_IDS 2
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/* must be called with ids->mutex acquired.*/
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int ipc_findkey(struct ipc_ids* ids, key_t key);
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int ipc_addid(struct ipc_ids* ids, struct kern_ipc_perm* new, int size);
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/* must be called with both locks acquired. */
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struct kern_ipc_perm* ipc_rmid(struct ipc_ids* ids, int id);
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int ipcperms (struct kern_ipc_perm *ipcp, short flg);
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/* for rare, potentially huge allocations.
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* both function can sleep
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*/
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void* ipc_alloc(int size);
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void ipc_free(void* ptr, int size);
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/*
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* For allocation that need to be freed by RCU.
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* Objects are reference counted, they start with reference count 1.
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* getref increases the refcount, the putref call that reduces the recount
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* to 0 schedules the rcu destruction. Caller must guarantee locking.
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*/
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void* ipc_rcu_alloc(int size);
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void ipc_rcu_getref(void *ptr);
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void ipc_rcu_putref(void *ptr);
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static inline void __ipc_fini_ids(struct ipc_ids *ids,
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struct ipc_id_ary *entries)
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{
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if (entries != &ids->nullentry)
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ipc_rcu_putref(entries);
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}
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static inline void ipc_fini_ids(struct ipc_ids *ids)
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{
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__ipc_fini_ids(ids, ids->entries);
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}
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struct kern_ipc_perm* ipc_get(struct ipc_ids* ids, int id);
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struct kern_ipc_perm* ipc_lock(struct ipc_ids* ids, int id);
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void ipc_lock_by_ptr(struct kern_ipc_perm *ipcp);
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void ipc_unlock(struct kern_ipc_perm* perm);
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int ipc_buildid(struct ipc_ids* ids, int id, int seq);
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int ipc_checkid(struct ipc_ids* ids, struct kern_ipc_perm* ipcp, int uid);
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void kernel_to_ipc64_perm(struct kern_ipc_perm *in, struct ipc64_perm *out);
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void ipc64_perm_to_ipc_perm(struct ipc64_perm *in, struct ipc_perm *out);
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#if defined(__ia64__) || defined(__x86_64__) || defined(__hppa__) || defined(__XTENSA__)
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/* On IA-64, we always use the "64-bit version" of the IPC structures. */
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# define ipc_parse_version(cmd) IPC_64
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#else
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int ipc_parse_version (int *cmd);
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#endif
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extern void free_msg(struct msg_msg *msg);
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extern struct msg_msg *load_msg(const void __user *src, int len);
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extern int store_msg(void __user *dest, struct msg_msg *msg, int len);
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#endif
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