1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 /* Internal procfs definitions 3 * 4 * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved. 5 * Written by David Howells (dhowells@redhat.com) 6 */ 7 8 #include <linux/proc_fs.h> 9 #include <linux/proc_ns.h> 10 #include <linux/refcount.h> 11 #include <linux/spinlock.h> 12 #include <linux/atomic.h> 13 #include <linux/binfmts.h> 14 #include <linux/sched/coredump.h> 15 #include <linux/sched/task.h> 16 17 struct ctl_table_header; 18 struct mempolicy; 19 20 /* 21 * This is not completely implemented yet. The idea is to 22 * create an in-memory tree (like the actual /proc filesystem 23 * tree) of these proc_dir_entries, so that we can dynamically 24 * add new files to /proc. 25 * 26 * parent/subdir are used for the directory structure (every /proc file has a 27 * parent, but "subdir" is empty for all non-directory entries). 28 * subdir_node is used to build the rb tree "subdir" of the parent. 29 */ 30 struct proc_dir_entry { 31 /* 32 * number of callers into module in progress; 33 * negative -> it's going away RSN 34 */ 35 atomic_t in_use; 36 refcount_t refcnt; 37 struct list_head pde_openers; /* who did ->open, but not ->release */ 38 /* protects ->pde_openers and all struct pde_opener instances */ 39 spinlock_t pde_unload_lock; 40 struct completion *pde_unload_completion; 41 const struct inode_operations *proc_iops; 42 union { 43 const struct proc_ops *proc_ops; 44 const struct file_operations *proc_dir_ops; 45 }; 46 const struct dentry_operations *proc_dops; 47 union { 48 const struct seq_operations *seq_ops; 49 int (*single_show)(struct seq_file *, void *); 50 }; 51 proc_write_t write; 52 void *data; 53 unsigned int state_size; 54 unsigned int low_ino; 55 nlink_t nlink; 56 kuid_t uid; 57 kgid_t gid; 58 loff_t size; 59 struct proc_dir_entry *parent; 60 struct rb_root subdir; 61 struct rb_node subdir_node; 62 char *name; 63 umode_t mode; 64 u8 flags; 65 u8 namelen; 66 char inline_name[]; 67 } __randomize_layout; 68 69 #define SIZEOF_PDE ( \ 70 sizeof(struct proc_dir_entry) < 128 ? 128 : \ 71 sizeof(struct proc_dir_entry) < 192 ? 192 : \ 72 sizeof(struct proc_dir_entry) < 256 ? 256 : \ 73 sizeof(struct proc_dir_entry) < 512 ? 512 : \ 74 0) 75 #define SIZEOF_PDE_INLINE_NAME (SIZEOF_PDE - sizeof(struct proc_dir_entry)) 76 77 static inline bool pde_is_permanent(const struct proc_dir_entry *pde) 78 { 79 return pde->flags & PROC_ENTRY_PERMANENT; 80 } 81 82 extern struct kmem_cache *proc_dir_entry_cache; 83 void pde_free(struct proc_dir_entry *pde); 84 85 union proc_op { 86 int (*proc_get_link)(struct dentry *, struct path *); 87 int (*proc_show)(struct seq_file *m, 88 struct pid_namespace *ns, struct pid *pid, 89 struct task_struct *task); 90 const char *lsm; 91 }; 92 93 struct proc_inode { 94 struct pid *pid; 95 unsigned int fd; 96 union proc_op op; 97 struct proc_dir_entry *pde; 98 struct ctl_table_header *sysctl; 99 struct ctl_table *sysctl_entry; 100 struct hlist_node sibling_inodes; 101 const struct proc_ns_operations *ns_ops; 102 struct inode vfs_inode; 103 } __randomize_layout; 104 105 /* 106 * General functions 107 */ 108 static inline struct proc_inode *PROC_I(const struct inode *inode) 109 { 110 return container_of(inode, struct proc_inode, vfs_inode); 111 } 112 113 static inline struct proc_dir_entry *PDE(const struct inode *inode) 114 { 115 return PROC_I(inode)->pde; 116 } 117 118 static inline void *__PDE_DATA(const struct inode *inode) 119 { 120 return PDE(inode)->data; 121 } 122 123 static inline struct pid *proc_pid(const struct inode *inode) 124 { 125 return PROC_I(inode)->pid; 126 } 127 128 static inline struct task_struct *get_proc_task(const struct inode *inode) 129 { 130 return get_pid_task(proc_pid(inode), PIDTYPE_PID); 131 } 132 133 void task_dump_owner(struct task_struct *task, umode_t mode, 134 kuid_t *ruid, kgid_t *rgid); 135 136 unsigned name_to_int(const struct qstr *qstr); 137 /* 138 * Offset of the first process in the /proc root directory.. 139 */ 140 #define FIRST_PROCESS_ENTRY 256 141 142 /* Worst case buffer size needed for holding an integer. */ 143 #define PROC_NUMBUF 13 144 145 /* 146 * array.c 147 */ 148 extern const struct file_operations proc_tid_children_operations; 149 150 extern void proc_task_name(struct seq_file *m, struct task_struct *p, 151 bool escape); 152 extern int proc_tid_stat(struct seq_file *, struct pid_namespace *, 153 struct pid *, struct task_struct *); 154 extern int proc_tgid_stat(struct seq_file *, struct pid_namespace *, 155 struct pid *, struct task_struct *); 156 extern int proc_pid_status(struct seq_file *, struct pid_namespace *, 157 struct pid *, struct task_struct *); 158 extern int proc_pid_statm(struct seq_file *, struct pid_namespace *, 159 struct pid *, struct task_struct *); 160 161 /* 162 * base.c 163 */ 164 extern const struct dentry_operations pid_dentry_operations; 165 extern int pid_getattr(const struct path *, struct kstat *, u32, unsigned int); 166 extern int proc_setattr(struct dentry *, struct iattr *); 167 extern void proc_pid_evict_inode(struct proc_inode *); 168 extern struct inode *proc_pid_make_inode(struct super_block *, struct task_struct *, umode_t); 169 extern void pid_update_inode(struct task_struct *, struct inode *); 170 extern int pid_delete_dentry(const struct dentry *); 171 extern int proc_pid_readdir(struct file *, struct dir_context *); 172 struct dentry *proc_pid_lookup(struct dentry *, unsigned int); 173 extern loff_t mem_lseek(struct file *, loff_t, int); 174 175 /* Lookups */ 176 typedef struct dentry *instantiate_t(struct dentry *, 177 struct task_struct *, const void *); 178 bool proc_fill_cache(struct file *, struct dir_context *, const char *, unsigned int, 179 instantiate_t, struct task_struct *, const void *); 180 181 /* 182 * generic.c 183 */ 184 struct proc_dir_entry *proc_create_reg(const char *name, umode_t mode, 185 struct proc_dir_entry **parent, void *data); 186 struct proc_dir_entry *proc_register(struct proc_dir_entry *dir, 187 struct proc_dir_entry *dp); 188 extern struct dentry *proc_lookup(struct inode *, struct dentry *, unsigned int); 189 struct dentry *proc_lookup_de(struct inode *, struct dentry *, struct proc_dir_entry *); 190 extern int proc_readdir(struct file *, struct dir_context *); 191 int proc_readdir_de(struct file *, struct dir_context *, struct proc_dir_entry *); 192 193 static inline void pde_get(struct proc_dir_entry *pde) 194 { 195 refcount_inc(&pde->refcnt); 196 } 197 extern void pde_put(struct proc_dir_entry *); 198 199 static inline bool is_empty_pde(const struct proc_dir_entry *pde) 200 { 201 return S_ISDIR(pde->mode) && !pde->proc_iops; 202 } 203 extern ssize_t proc_simple_write(struct file *, const char __user *, size_t, loff_t *); 204 205 /* 206 * inode.c 207 */ 208 struct pde_opener { 209 struct list_head lh; 210 struct file *file; 211 bool closing; 212 struct completion *c; 213 } __randomize_layout; 214 extern const struct inode_operations proc_link_inode_operations; 215 extern const struct inode_operations proc_pid_link_inode_operations; 216 extern const struct super_operations proc_sops; 217 218 void proc_init_kmemcache(void); 219 void proc_invalidate_siblings_dcache(struct hlist_head *inodes, spinlock_t *lock); 220 void set_proc_pid_nlink(void); 221 extern struct inode *proc_get_inode(struct super_block *, struct proc_dir_entry *); 222 extern void proc_entry_rundown(struct proc_dir_entry *); 223 224 /* 225 * proc_namespaces.c 226 */ 227 extern const struct inode_operations proc_ns_dir_inode_operations; 228 extern const struct file_operations proc_ns_dir_operations; 229 230 /* 231 * proc_net.c 232 */ 233 extern const struct file_operations proc_net_operations; 234 extern const struct inode_operations proc_net_inode_operations; 235 236 #ifdef CONFIG_NET 237 extern int proc_net_init(void); 238 #else 239 static inline int proc_net_init(void) { return 0; } 240 #endif 241 242 /* 243 * proc_self.c 244 */ 245 extern int proc_setup_self(struct super_block *); 246 247 /* 248 * proc_thread_self.c 249 */ 250 extern int proc_setup_thread_self(struct super_block *); 251 extern void proc_thread_self_init(void); 252 253 /* 254 * proc_sysctl.c 255 */ 256 #ifdef CONFIG_PROC_SYSCTL 257 extern int proc_sys_init(void); 258 extern void proc_sys_evict_inode(struct inode *inode, 259 struct ctl_table_header *head); 260 #else 261 static inline void proc_sys_init(void) { } 262 static inline void proc_sys_evict_inode(struct inode *inode, 263 struct ctl_table_header *head) { } 264 #endif 265 266 /* 267 * proc_tty.c 268 */ 269 #ifdef CONFIG_TTY 270 extern void proc_tty_init(void); 271 #else 272 static inline void proc_tty_init(void) {} 273 #endif 274 275 /* 276 * root.c 277 */ 278 extern struct proc_dir_entry proc_root; 279 280 extern void proc_self_init(void); 281 282 /* 283 * task_[no]mmu.c 284 */ 285 struct mem_size_stats; 286 struct proc_maps_private { 287 struct inode *inode; 288 struct task_struct *task; 289 struct mm_struct *mm; 290 #ifdef CONFIG_MMU 291 struct vm_area_struct *tail_vma; 292 #endif 293 #ifdef CONFIG_NUMA 294 struct mempolicy *task_mempolicy; 295 #endif 296 } __randomize_layout; 297 298 struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode); 299 300 extern const struct file_operations proc_pid_maps_operations; 301 extern const struct file_operations proc_pid_numa_maps_operations; 302 extern const struct file_operations proc_pid_smaps_operations; 303 extern const struct file_operations proc_pid_smaps_rollup_operations; 304 extern const struct file_operations proc_clear_refs_operations; 305 extern const struct file_operations proc_pagemap_operations; 306 307 extern unsigned long task_vsize(struct mm_struct *); 308 extern unsigned long task_statm(struct mm_struct *, 309 unsigned long *, unsigned long *, 310 unsigned long *, unsigned long *); 311 extern void task_mem(struct seq_file *, struct mm_struct *); 312 313 extern const struct dentry_operations proc_net_dentry_ops; 314 static inline void pde_force_lookup(struct proc_dir_entry *pde) 315 { 316 /* /proc/net/ entries can be changed under us by setns(CLONE_NEWNET) */ 317 pde->proc_dops = &proc_net_dentry_ops; 318 } 319