1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _LINUX_PID_NS_H 3 #define _LINUX_PID_NS_H 4 5 #include <linux/sched.h> 6 #include <linux/bug.h> 7 #include <linux/mm.h> 8 #include <linux/workqueue.h> 9 #include <linux/threads.h> 10 #include <linux/nsproxy.h> 11 #include <linux/ns_common.h> 12 #include <linux/idr.h> 13 14 /* MAX_PID_NS_LEVEL is needed for limiting size of 'struct pid' */ 15 #define MAX_PID_NS_LEVEL 32 16 17 struct fs_pin; 18 19 #if defined(CONFIG_SYSCTL) && defined(CONFIG_MEMFD_CREATE) 20 /* modes for vm.memfd_noexec sysctl */ 21 #define MEMFD_NOEXEC_SCOPE_EXEC 0 /* MFD_EXEC implied if unset */ 22 #define MEMFD_NOEXEC_SCOPE_NOEXEC_SEAL 1 /* MFD_NOEXEC_SEAL implied if unset */ 23 #define MEMFD_NOEXEC_SCOPE_NOEXEC_ENFORCED 2 /* same as 1, except MFD_EXEC rejected */ 24 #endif 25 26 struct pid_namespace { 27 struct idr idr; 28 struct rcu_head rcu; 29 unsigned int pid_allocated; 30 struct task_struct *child_reaper; 31 struct kmem_cache *pid_cachep; 32 unsigned int level; 33 int pid_max; 34 struct pid_namespace *parent; 35 #ifdef CONFIG_BSD_PROCESS_ACCT 36 struct fs_pin *bacct; 37 #endif 38 struct user_namespace *user_ns; 39 struct ucounts *ucounts; 40 int reboot; /* group exit code if this pidns was rebooted */ 41 struct ns_common ns; 42 struct work_struct work; 43 #ifdef CONFIG_SYSCTL 44 struct ctl_table_set set; 45 struct ctl_table_header *sysctls; 46 #if defined(CONFIG_MEMFD_CREATE) 47 int memfd_noexec_scope; 48 #endif 49 #endif 50 } __randomize_layout; 51 52 extern struct pid_namespace init_pid_ns; 53 54 #define PIDNS_ADDING (1U << 31) 55 56 #ifdef CONFIG_PID_NS 57 static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns) 58 { 59 if (ns != &init_pid_ns) 60 refcount_inc(&ns->ns.count); 61 return ns; 62 } 63 64 #if defined(CONFIG_SYSCTL) && defined(CONFIG_MEMFD_CREATE) 65 static inline int pidns_memfd_noexec_scope(struct pid_namespace *ns) 66 { 67 int scope = MEMFD_NOEXEC_SCOPE_EXEC; 68 69 for (; ns; ns = ns->parent) 70 scope = max(scope, READ_ONCE(ns->memfd_noexec_scope)); 71 72 return scope; 73 } 74 #else 75 static inline int pidns_memfd_noexec_scope(struct pid_namespace *ns) 76 { 77 return 0; 78 } 79 #endif 80 81 extern struct pid_namespace *copy_pid_ns(unsigned long flags, 82 struct user_namespace *user_ns, struct pid_namespace *ns); 83 extern void zap_pid_ns_processes(struct pid_namespace *pid_ns); 84 extern int reboot_pid_ns(struct pid_namespace *pid_ns, int cmd); 85 extern void put_pid_ns(struct pid_namespace *ns); 86 87 #else /* !CONFIG_PID_NS */ 88 #include <linux/err.h> 89 90 static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns) 91 { 92 return ns; 93 } 94 95 static inline int pidns_memfd_noexec_scope(struct pid_namespace *ns) 96 { 97 return 0; 98 } 99 100 static inline struct pid_namespace *copy_pid_ns(unsigned long flags, 101 struct user_namespace *user_ns, struct pid_namespace *ns) 102 { 103 if (flags & CLONE_NEWPID) 104 ns = ERR_PTR(-EINVAL); 105 return ns; 106 } 107 108 static inline void put_pid_ns(struct pid_namespace *ns) 109 { 110 } 111 112 static inline void zap_pid_ns_processes(struct pid_namespace *ns) 113 { 114 BUG(); 115 } 116 117 static inline int reboot_pid_ns(struct pid_namespace *pid_ns, int cmd) 118 { 119 return 0; 120 } 121 #endif /* CONFIG_PID_NS */ 122 123 extern struct pid_namespace *task_active_pid_ns(struct task_struct *tsk); 124 void pidhash_init(void); 125 void pid_idr_init(void); 126 int register_pidns_sysctls(struct pid_namespace *pidns); 127 void unregister_pidns_sysctls(struct pid_namespace *pidns); 128 129 static inline bool task_is_in_init_pid_ns(struct task_struct *tsk) 130 { 131 return task_active_pid_ns(tsk) == &init_pid_ns; 132 } 133 134 #endif /* _LINUX_PID_NS_H */ 135