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 struct pid_namespace *parent; 34 #ifdef CONFIG_BSD_PROCESS_ACCT 35 struct fs_pin *bacct; 36 #endif 37 struct user_namespace *user_ns; 38 struct ucounts *ucounts; 39 int reboot; /* group exit code if this pidns was rebooted */ 40 struct ns_common ns; 41 #if defined(CONFIG_SYSCTL) && defined(CONFIG_MEMFD_CREATE) 42 int memfd_noexec_scope; 43 #endif 44 } __randomize_layout; 45 46 extern struct pid_namespace init_pid_ns; 47 48 #define PIDNS_ADDING (1U << 31) 49 50 #ifdef CONFIG_PID_NS 51 static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns) 52 { 53 if (ns != &init_pid_ns) 54 refcount_inc(&ns->ns.count); 55 return ns; 56 } 57 58 #if defined(CONFIG_SYSCTL) && defined(CONFIG_MEMFD_CREATE) 59 static inline int pidns_memfd_noexec_scope(struct pid_namespace *ns) 60 { 61 int scope = MEMFD_NOEXEC_SCOPE_EXEC; 62 63 for (; ns; ns = ns->parent) 64 scope = max(scope, READ_ONCE(ns->memfd_noexec_scope)); 65 66 return scope; 67 } 68 #else 69 static inline int pidns_memfd_noexec_scope(struct pid_namespace *ns) 70 { 71 return 0; 72 } 73 #endif 74 75 extern struct pid_namespace *copy_pid_ns(unsigned long flags, 76 struct user_namespace *user_ns, struct pid_namespace *ns); 77 extern void zap_pid_ns_processes(struct pid_namespace *pid_ns); 78 extern int reboot_pid_ns(struct pid_namespace *pid_ns, int cmd); 79 extern void put_pid_ns(struct pid_namespace *ns); 80 81 #else /* !CONFIG_PID_NS */ 82 #include <linux/err.h> 83 84 static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns) 85 { 86 return ns; 87 } 88 89 static inline int pidns_memfd_noexec_scope(struct pid_namespace *ns) 90 { 91 return 0; 92 } 93 94 static inline struct pid_namespace *copy_pid_ns(unsigned long flags, 95 struct user_namespace *user_ns, struct pid_namespace *ns) 96 { 97 if (flags & CLONE_NEWPID) 98 ns = ERR_PTR(-EINVAL); 99 return ns; 100 } 101 102 static inline void put_pid_ns(struct pid_namespace *ns) 103 { 104 } 105 106 static inline void zap_pid_ns_processes(struct pid_namespace *ns) 107 { 108 BUG(); 109 } 110 111 static inline int reboot_pid_ns(struct pid_namespace *pid_ns, int cmd) 112 { 113 return 0; 114 } 115 #endif /* CONFIG_PID_NS */ 116 117 extern struct pid_namespace *task_active_pid_ns(struct task_struct *tsk); 118 void pidhash_init(void); 119 void pid_idr_init(void); 120 121 static inline bool task_is_in_init_pid_ns(struct task_struct *tsk) 122 { 123 return task_active_pid_ns(tsk) == &init_pid_ns; 124 } 125 126 #endif /* _LINUX_PID_NS_H */ 127