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 struct ucounts *ucounts;
62
63 struct ns_common ns;
64};
65
66extern struct ipc_namespace init_ipc_ns;
67extern spinlock_t mq_lock;
68
69#ifdef CONFIG_SYSVIPC
70extern void shm_destroy_orphaned(struct ipc_namespace *ns);
71#else /* CONFIG_SYSVIPC */
72static inline void shm_destroy_orphaned(struct ipc_namespace *ns) {}
73#endif /* CONFIG_SYSVIPC */
74
75#ifdef CONFIG_POSIX_MQUEUE
76extern int mq_init_ns(struct ipc_namespace *ns);
77/*
78 * POSIX Message Queue default values:
79 *
80 * MIN_*: Lowest value an admin can set the maximum unprivileged limit to
81 * DFLT_*MAX: Default values for the maximum unprivileged limits
82 * DFLT_{MSG,MSGSIZE}: Default values used when the user doesn't supply
83 * an attribute to the open call and the queue must be created
84 * HARD_*: Highest value the maximums can be set to. These are enforced
85 * on CAP_SYS_RESOURCE apps as well making them inviolate (so make them
86 * suitably high)
87 *
88 * POSIX Requirements:
89 * Per app minimum openable message queues - 8. This does not map well
90 * to the fact that we limit the number of queues on a per namespace
91 * basis instead of a per app basis. So, make the default high enough
92 * that no given app should have a hard time opening 8 queues.
93 * Minimum maximum for HARD_MSGMAX - 32767. I bumped this to 65536.
94 * Minimum maximum for HARD_MSGSIZEMAX - POSIX is silent on this. However,
95 * we have run into a situation where running applications in the wild
96 * require this to be at least 5MB, and preferably 10MB, so I set the
97 * value to 16MB in hopes that this user is the worst of the bunch and
98 * the new maximum will handle anyone else. I may have to revisit this
99 * in the future.
100 */
101#define DFLT_QUEUESMAX 256
102#define MIN_MSGMAX 1
103#define DFLT_MSG 10U
104#define DFLT_MSGMAX 10
105#define HARD_MSGMAX 65536
106#define MIN_MSGSIZEMAX 128
107#define DFLT_MSGSIZE 8192U
108#define DFLT_MSGSIZEMAX 8192
109#define HARD_MSGSIZEMAX (16*1024*1024)
110#else
111static inline int mq_init_ns(struct ipc_namespace *ns) { return 0; }
112#endif
113
114#if defined(CONFIG_IPC_NS)
115extern struct ipc_namespace *copy_ipcs(unsigned long flags,
116 struct user_namespace *user_ns, struct ipc_namespace *ns);
117
118static inline struct ipc_namespace *get_ipc_ns(struct ipc_namespace *ns)
119{
120 if (ns)
121 atomic_inc(&ns->count);
122 return ns;
123}
124
125extern void put_ipc_ns(struct ipc_namespace *ns);
126#else
127static inline struct ipc_namespace *copy_ipcs(unsigned long flags,
128 struct user_namespace *user_ns, struct ipc_namespace *ns)
129{
130 if (flags & CLONE_NEWIPC)
131 return ERR_PTR(-EINVAL);
132
133 return ns;
134}
135
136static inline struct ipc_namespace *get_ipc_ns(struct ipc_namespace *ns)
137{
138 return ns;
139}
140
141static inline void put_ipc_ns(struct ipc_namespace *ns)
142{
143}
144#endif
145
146#ifdef CONFIG_POSIX_MQUEUE_SYSCTL
147
148struct ctl_table_header;
149extern struct ctl_table_header *mq_register_sysctl_table(void);
150
151#else /* CONFIG_POSIX_MQUEUE_SYSCTL */
152
153static inline struct ctl_table_header *mq_register_sysctl_table(void)
154{
155 return NULL;
156}
157
158#endif /* CONFIG_POSIX_MQUEUE_SYSCTL */
159#endif