1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | #ifndef __IPC_NAMESPACE_H__ |
3 | #define __IPC_NAMESPACE_H__ |
4 | |
5 | #include <linux/err.h> |
6 | #include <linux/idr.h> |
7 | #include <linux/rwsem.h> |
8 | #include <linux/notifier.h> |
9 | #include <linux/nsproxy.h> |
10 | #include <linux/ns_common.h> |
11 | #include <linux/refcount.h> |
12 | #include <linux/rhashtable-types.h> |
13 | #include <linux/sysctl.h> |
14 | #include <linux/percpu_counter.h> |
15 | |
16 | struct user_namespace; |
17 | |
18 | struct ipc_ids { |
19 | int in_use; |
20 | unsigned short seq; |
21 | struct rw_semaphore rwsem; |
22 | struct idr ipcs_idr; |
23 | int max_idx; |
24 | int last_idx; /* For wrap around detection */ |
25 | #ifdef CONFIG_CHECKPOINT_RESTORE |
26 | int next_id; |
27 | #endif |
28 | struct rhashtable key_ht; |
29 | }; |
30 | |
31 | struct ipc_namespace { |
32 | struct ipc_ids ids[3]; |
33 | |
34 | int sem_ctls[4]; |
35 | int used_sems; |
36 | |
37 | unsigned int msg_ctlmax; |
38 | unsigned int msg_ctlmnb; |
39 | unsigned int msg_ctlmni; |
40 | struct percpu_counter percpu_msg_bytes; |
41 | struct percpu_counter percpu_msg_hdrs; |
42 | |
43 | size_t shm_ctlmax; |
44 | size_t shm_ctlall; |
45 | unsigned long shm_tot; |
46 | int shm_ctlmni; |
47 | /* |
48 | * Defines whether IPC_RMID is forced for _all_ shm segments regardless |
49 | * of shmctl() |
50 | */ |
51 | int shm_rmid_forced; |
52 | |
53 | struct notifier_block ipcns_nb; |
54 | |
55 | /* The kern_mount of the mqueuefs sb. We take a ref on it */ |
56 | struct vfsmount *mq_mnt; |
57 | |
58 | /* # queues in this ns, protected by mq_lock */ |
59 | unsigned int mq_queues_count; |
60 | |
61 | /* next fields are set through sysctl */ |
62 | unsigned int mq_queues_max; /* initialized to DFLT_QUEUESMAX */ |
63 | unsigned int mq_msg_max; /* initialized to DFLT_MSGMAX */ |
64 | unsigned int mq_msgsize_max; /* initialized to DFLT_MSGSIZEMAX */ |
65 | unsigned int mq_msg_default; |
66 | unsigned int mq_msgsize_default; |
67 | |
68 | struct ctl_table_set mq_set; |
69 | struct ctl_table_header *mq_sysctls; |
70 | |
71 | struct ctl_table_set ipc_set; |
72 | struct ctl_table_header *ipc_sysctls; |
73 | |
74 | /* user_ns which owns the ipc ns */ |
75 | struct user_namespace *user_ns; |
76 | struct ucounts *ucounts; |
77 | |
78 | struct llist_node mnt_llist; |
79 | |
80 | struct ns_common ns; |
81 | } __randomize_layout; |
82 | |
83 | extern struct ipc_namespace init_ipc_ns; |
84 | extern spinlock_t mq_lock; |
85 | |
86 | #ifdef CONFIG_SYSVIPC |
87 | extern void shm_destroy_orphaned(struct ipc_namespace *ns); |
88 | #else /* CONFIG_SYSVIPC */ |
89 | static inline void shm_destroy_orphaned(struct ipc_namespace *ns) {} |
90 | #endif /* CONFIG_SYSVIPC */ |
91 | |
92 | #ifdef CONFIG_POSIX_MQUEUE |
93 | extern int mq_init_ns(struct ipc_namespace *ns); |
94 | /* |
95 | * POSIX Message Queue default values: |
96 | * |
97 | * MIN_*: Lowest value an admin can set the maximum unprivileged limit to |
98 | * DFLT_*MAX: Default values for the maximum unprivileged limits |
99 | * DFLT_{MSG,MSGSIZE}: Default values used when the user doesn't supply |
100 | * an attribute to the open call and the queue must be created |
101 | * HARD_*: Highest value the maximums can be set to. These are enforced |
102 | * on CAP_SYS_RESOURCE apps as well making them inviolate (so make them |
103 | * suitably high) |
104 | * |
105 | * POSIX Requirements: |
106 | * Per app minimum openable message queues - 8. This does not map well |
107 | * to the fact that we limit the number of queues on a per namespace |
108 | * basis instead of a per app basis. So, make the default high enough |
109 | * that no given app should have a hard time opening 8 queues. |
110 | * Minimum maximum for HARD_MSGMAX - 32767. I bumped this to 65536. |
111 | * Minimum maximum for HARD_MSGSIZEMAX - POSIX is silent on this. However, |
112 | * we have run into a situation where running applications in the wild |
113 | * require this to be at least 5MB, and preferably 10MB, so I set the |
114 | * value to 16MB in hopes that this user is the worst of the bunch and |
115 | * the new maximum will handle anyone else. I may have to revisit this |
116 | * in the future. |
117 | */ |
118 | #define DFLT_QUEUESMAX 256 |
119 | #define MIN_MSGMAX 1 |
120 | #define DFLT_MSG 10U |
121 | #define DFLT_MSGMAX 10 |
122 | #define HARD_MSGMAX 65536 |
123 | #define MIN_MSGSIZEMAX 128 |
124 | #define DFLT_MSGSIZE 8192U |
125 | #define DFLT_MSGSIZEMAX 8192 |
126 | #define HARD_MSGSIZEMAX (16*1024*1024) |
127 | #else |
128 | static inline int mq_init_ns(struct ipc_namespace *ns) { return 0; } |
129 | #endif |
130 | |
131 | #if defined(CONFIG_IPC_NS) |
132 | extern struct ipc_namespace *copy_ipcs(unsigned long flags, |
133 | struct user_namespace *user_ns, struct ipc_namespace *ns); |
134 | |
135 | static inline struct ipc_namespace *get_ipc_ns(struct ipc_namespace *ns) |
136 | { |
137 | if (ns) |
138 | refcount_inc(r: &ns->ns.count); |
139 | return ns; |
140 | } |
141 | |
142 | static inline struct ipc_namespace *get_ipc_ns_not_zero(struct ipc_namespace *ns) |
143 | { |
144 | if (ns) { |
145 | if (refcount_inc_not_zero(r: &ns->ns.count)) |
146 | return ns; |
147 | } |
148 | |
149 | return NULL; |
150 | } |
151 | |
152 | extern void put_ipc_ns(struct ipc_namespace *ns); |
153 | #else |
154 | static inline struct ipc_namespace *copy_ipcs(unsigned long flags, |
155 | struct user_namespace *user_ns, struct ipc_namespace *ns) |
156 | { |
157 | if (flags & CLONE_NEWIPC) |
158 | return ERR_PTR(-EINVAL); |
159 | |
160 | return ns; |
161 | } |
162 | |
163 | static inline struct ipc_namespace *get_ipc_ns(struct ipc_namespace *ns) |
164 | { |
165 | return ns; |
166 | } |
167 | |
168 | static inline struct ipc_namespace *get_ipc_ns_not_zero(struct ipc_namespace *ns) |
169 | { |
170 | return ns; |
171 | } |
172 | |
173 | static inline void put_ipc_ns(struct ipc_namespace *ns) |
174 | { |
175 | } |
176 | #endif |
177 | |
178 | #ifdef CONFIG_POSIX_MQUEUE_SYSCTL |
179 | |
180 | void retire_mq_sysctls(struct ipc_namespace *ns); |
181 | bool setup_mq_sysctls(struct ipc_namespace *ns); |
182 | |
183 | #else /* CONFIG_POSIX_MQUEUE_SYSCTL */ |
184 | |
185 | static inline void retire_mq_sysctls(struct ipc_namespace *ns) |
186 | { |
187 | } |
188 | |
189 | static inline bool setup_mq_sysctls(struct ipc_namespace *ns) |
190 | { |
191 | return true; |
192 | } |
193 | |
194 | #endif /* CONFIG_POSIX_MQUEUE_SYSCTL */ |
195 | |
196 | #ifdef CONFIG_SYSVIPC_SYSCTL |
197 | |
198 | bool setup_ipc_sysctls(struct ipc_namespace *ns); |
199 | void retire_ipc_sysctls(struct ipc_namespace *ns); |
200 | |
201 | #else /* CONFIG_SYSVIPC_SYSCTL */ |
202 | |
203 | static inline void retire_ipc_sysctls(struct ipc_namespace *ns) |
204 | { |
205 | } |
206 | |
207 | static inline bool setup_ipc_sysctls(struct ipc_namespace *ns) |
208 | { |
209 | return true; |
210 | } |
211 | |
212 | #endif /* CONFIG_SYSVIPC_SYSCTL */ |
213 | #endif |
214 | |