Linux kernel mirror (for testing)
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linux
1#ifndef __IPC_NAMESPACE_H__
2#define __IPC_NAMESPACE_H__
3
4#include <linux/err.h>
5#include <linux/idr.h>
6#include <linux/rwsem.h>
7#include <linux/notifier.h>
8#include <linux/nsproxy.h>
9#include <linux/ns_common.h>
10
11struct user_namespace;
12
13struct ipc_ids {
14 int in_use;
15 unsigned short seq;
16 struct rw_semaphore rwsem;
17 struct idr ipcs_idr;
18 int next_id;
19};
20
21struct ipc_namespace {
22 atomic_t count;
23 struct ipc_ids ids[3];
24
25 int sem_ctls[4];
26 int used_sems;
27
28 unsigned int msg_ctlmax;
29 unsigned int msg_ctlmnb;
30 unsigned int msg_ctlmni;
31 atomic_t msg_bytes;
32 atomic_t msg_hdrs;
33
34 size_t shm_ctlmax;
35 size_t shm_ctlall;
36 unsigned long shm_tot;
37 int shm_ctlmni;
38 /*
39 * Defines whether IPC_RMID is forced for _all_ shm segments regardless
40 * of shmctl()
41 */
42 int shm_rmid_forced;
43
44 struct notifier_block ipcns_nb;
45
46 /* The kern_mount of the mqueuefs sb. We take a ref on it */
47 struct vfsmount *mq_mnt;
48
49 /* # queues in this ns, protected by mq_lock */
50 unsigned int mq_queues_count;
51
52 /* next fields are set through sysctl */
53 unsigned int mq_queues_max; /* initialized to DFLT_QUEUESMAX */
54 unsigned int mq_msg_max; /* initialized to DFLT_MSGMAX */
55 unsigned int mq_msgsize_max; /* initialized to DFLT_MSGSIZEMAX */
56 unsigned int mq_msg_default;
57 unsigned int mq_msgsize_default;
58
59 /* user_ns which owns the ipc ns */
60 struct user_namespace *user_ns;
61
62 struct ns_common ns;
63};
64
65extern struct ipc_namespace init_ipc_ns;
66extern spinlock_t mq_lock;
67
68#ifdef CONFIG_SYSVIPC
69extern void shm_destroy_orphaned(struct ipc_namespace *ns);
70#else /* CONFIG_SYSVIPC */
71static inline void shm_destroy_orphaned(struct ipc_namespace *ns) {}
72#endif /* CONFIG_SYSVIPC */
73
74#ifdef CONFIG_POSIX_MQUEUE
75extern int mq_init_ns(struct ipc_namespace *ns);
76/*
77 * POSIX Message Queue default values:
78 *
79 * MIN_*: Lowest value an admin can set the maximum unprivileged limit to
80 * DFLT_*MAX: Default values for the maximum unprivileged limits
81 * DFLT_{MSG,MSGSIZE}: Default values used when the user doesn't supply
82 * an attribute to the open call and the queue must be created
83 * HARD_*: Highest value the maximums can be set to. These are enforced
84 * on CAP_SYS_RESOURCE apps as well making them inviolate (so make them
85 * suitably high)
86 *
87 * POSIX Requirements:
88 * Per app minimum openable message queues - 8. This does not map well
89 * to the fact that we limit the number of queues on a per namespace
90 * basis instead of a per app basis. So, make the default high enough
91 * that no given app should have a hard time opening 8 queues.
92 * Minimum maximum for HARD_MSGMAX - 32767. I bumped this to 65536.
93 * Minimum maximum for HARD_MSGSIZEMAX - POSIX is silent on this. However,
94 * we have run into a situation where running applications in the wild
95 * require this to be at least 5MB, and preferably 10MB, so I set the
96 * value to 16MB in hopes that this user is the worst of the bunch and
97 * the new maximum will handle anyone else. I may have to revisit this
98 * in the future.
99 */
100#define DFLT_QUEUESMAX 256
101#define MIN_MSGMAX 1
102#define DFLT_MSG 10U
103#define DFLT_MSGMAX 10
104#define HARD_MSGMAX 65536
105#define MIN_MSGSIZEMAX 128
106#define DFLT_MSGSIZE 8192U
107#define DFLT_MSGSIZEMAX 8192
108#define HARD_MSGSIZEMAX (16*1024*1024)
109#else
110static inline int mq_init_ns(struct ipc_namespace *ns) { return 0; }
111#endif
112
113#if defined(CONFIG_IPC_NS)
114extern struct ipc_namespace *copy_ipcs(unsigned long flags,
115 struct user_namespace *user_ns, struct ipc_namespace *ns);
116
117static inline struct ipc_namespace *get_ipc_ns(struct ipc_namespace *ns)
118{
119 if (ns)
120 atomic_inc(&ns->count);
121 return ns;
122}
123
124extern void put_ipc_ns(struct ipc_namespace *ns);
125#else
126static inline struct ipc_namespace *copy_ipcs(unsigned long flags,
127 struct user_namespace *user_ns, struct ipc_namespace *ns)
128{
129 if (flags & CLONE_NEWIPC)
130 return ERR_PTR(-EINVAL);
131
132 return ns;
133}
134
135static inline struct ipc_namespace *get_ipc_ns(struct ipc_namespace *ns)
136{
137 return ns;
138}
139
140static inline void put_ipc_ns(struct ipc_namespace *ns)
141{
142}
143#endif
144
145#ifdef CONFIG_POSIX_MQUEUE_SYSCTL
146
147struct ctl_table_header;
148extern struct ctl_table_header *mq_register_sysctl_table(void);
149
150#else /* CONFIG_POSIX_MQUEUE_SYSCTL */
151
152static inline struct ctl_table_header *mq_register_sysctl_table(void)
153{
154 return NULL;
155}
156
157#endif /* CONFIG_POSIX_MQUEUE_SYSCTL */
158#endif