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