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 static inline void pde_make_permanent(struct proc_dir_entry *pde) 83 { 84 pde->flags |= PROC_ENTRY_PERMANENT; 85 } 86 87 extern struct kmem_cache *proc_dir_entry_cache; 88 void pde_free(struct proc_dir_entry *pde); 89 90 union proc_op { 91 int (*proc_get_link)(struct dentry *, struct path *); 92 int (*proc_show)(struct seq_file *m, 93 struct pid_namespace *ns, struct pid *pid, 94 struct task_struct *task); 95 const char *lsm; 96 }; 97 98 struct proc_inode { 99 struct pid *pid; 100 unsigned int fd; 101 union proc_op op; 102 struct proc_dir_entry *pde; 103 struct ctl_table_header *sysctl; 104 struct ctl_table *sysctl_entry; 105 struct hlist_node sibling_inodes; 106 const struct proc_ns_operations *ns_ops; 107 struct inode vfs_inode; 108 } __randomize_layout; 109 110 /* 111 * General functions 112 */ 113 static inline struct proc_inode *PROC_I(const struct inode *inode) 114 { 115 return container_of(inode, struct proc_inode, vfs_inode); 116 } 117 118 static inline struct proc_dir_entry *PDE(const struct inode *inode) 119 { 120 return PROC_I(inode)->pde; 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(struct mnt_idmap *, const struct path *, 166 struct kstat *, u32, unsigned int); 167 extern int proc_setattr(struct mnt_idmap *, struct dentry *, 168 struct iattr *); 169 extern void proc_pid_evict_inode(struct proc_inode *); 170 extern struct inode *proc_pid_make_inode(struct super_block *, struct task_struct *, umode_t); 171 extern void pid_update_inode(struct task_struct *, struct inode *); 172 extern int pid_delete_dentry(const struct dentry *); 173 extern int proc_pid_readdir(struct file *, struct dir_context *); 174 struct dentry *proc_pid_lookup(struct dentry *, unsigned int); 175 extern loff_t mem_lseek(struct file *, loff_t, int); 176 177 /* Lookups */ 178 typedef struct dentry *instantiate_t(struct dentry *, 179 struct task_struct *, const void *); 180 bool proc_fill_cache(struct file *, struct dir_context *, const char *, unsigned int, 181 instantiate_t, struct task_struct *, const void *); 182 183 /* 184 * generic.c 185 */ 186 struct proc_dir_entry *proc_create_reg(const char *name, umode_t mode, 187 struct proc_dir_entry **parent, void *data); 188 struct proc_dir_entry *proc_register(struct proc_dir_entry *dir, 189 struct proc_dir_entry *dp); 190 extern struct dentry *proc_lookup(struct inode *, struct dentry *, unsigned int); 191 struct dentry *proc_lookup_de(struct inode *, struct dentry *, struct proc_dir_entry *); 192 extern int proc_readdir(struct file *, struct dir_context *); 193 int proc_readdir_de(struct file *, struct dir_context *, struct proc_dir_entry *); 194 195 static inline void pde_get(struct proc_dir_entry *pde) 196 { 197 refcount_inc(&pde->refcnt); 198 } 199 extern void pde_put(struct proc_dir_entry *); 200 201 static inline bool is_empty_pde(const struct proc_dir_entry *pde) 202 { 203 return S_ISDIR(pde->mode) && !pde->proc_iops; 204 } 205 extern ssize_t proc_simple_write(struct file *, const char __user *, size_t, loff_t *); 206 207 /* 208 * inode.c 209 */ 210 struct pde_opener { 211 struct list_head lh; 212 struct file *file; 213 bool closing; 214 struct completion *c; 215 } __randomize_layout; 216 extern const struct inode_operations proc_link_inode_operations; 217 extern const struct inode_operations proc_pid_link_inode_operations; 218 extern const struct super_operations proc_sops; 219 220 void proc_init_kmemcache(void); 221 void proc_invalidate_siblings_dcache(struct hlist_head *inodes, spinlock_t *lock); 222 void set_proc_pid_nlink(void); 223 extern struct inode *proc_get_inode(struct super_block *, struct proc_dir_entry *); 224 extern void proc_entry_rundown(struct proc_dir_entry *); 225 226 /* 227 * proc_namespaces.c 228 */ 229 extern const struct inode_operations proc_ns_dir_inode_operations; 230 extern const struct file_operations proc_ns_dir_operations; 231 232 /* 233 * proc_net.c 234 */ 235 extern const struct file_operations proc_net_operations; 236 extern const struct inode_operations proc_net_inode_operations; 237 238 #ifdef CONFIG_NET 239 extern int proc_net_init(void); 240 #else 241 static inline int proc_net_init(void) { return 0; } 242 #endif 243 244 /* 245 * proc_self.c 246 */ 247 extern int proc_setup_self(struct super_block *); 248 249 /* 250 * proc_thread_self.c 251 */ 252 extern int proc_setup_thread_self(struct super_block *); 253 extern void proc_thread_self_init(void); 254 255 /* 256 * proc_sysctl.c 257 */ 258 #ifdef CONFIG_PROC_SYSCTL 259 extern int proc_sys_init(void); 260 extern void proc_sys_evict_inode(struct inode *inode, 261 struct ctl_table_header *head); 262 #else 263 static inline void proc_sys_init(void) { } 264 static inline void proc_sys_evict_inode(struct inode *inode, 265 struct ctl_table_header *head) { } 266 #endif 267 268 /* 269 * proc_tty.c 270 */ 271 #ifdef CONFIG_TTY 272 extern void proc_tty_init(void); 273 #else 274 static inline void proc_tty_init(void) {} 275 #endif 276 277 /* 278 * root.c 279 */ 280 extern struct proc_dir_entry proc_root; 281 282 extern void proc_self_init(void); 283 284 /* 285 * task_[no]mmu.c 286 */ 287 struct mem_size_stats; 288 struct proc_maps_private { 289 struct inode *inode; 290 struct task_struct *task; 291 struct mm_struct *mm; 292 #ifdef CONFIG_MMU 293 struct vma_iterator iter; 294 #endif 295 #ifdef CONFIG_NUMA 296 struct mempolicy *task_mempolicy; 297 #endif 298 } __randomize_layout; 299 300 struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode); 301 302 extern const struct file_operations proc_pid_maps_operations; 303 extern const struct file_operations proc_pid_numa_maps_operations; 304 extern const struct file_operations proc_pid_smaps_operations; 305 extern const struct file_operations proc_pid_smaps_rollup_operations; 306 extern const struct file_operations proc_clear_refs_operations; 307 extern const struct file_operations proc_pagemap_operations; 308 309 extern unsigned long task_vsize(struct mm_struct *); 310 extern unsigned long task_statm(struct mm_struct *, 311 unsigned long *, unsigned long *, 312 unsigned long *, unsigned long *); 313 extern void task_mem(struct seq_file *, struct mm_struct *); 314 315 extern const struct dentry_operations proc_net_dentry_ops; 316 static inline void pde_force_lookup(struct proc_dir_entry *pde) 317 { 318 /* /proc/net/ entries can be changed under us by setns(CLONE_NEWNET) */ 319 pde->proc_dops = &proc_net_dentry_ops; 320 } 321