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