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 static inline bool pde_has_proc_read_iter(const struct proc_dir_entry *pde) 88 { 89 return pde->flags & PROC_ENTRY_proc_read_iter; 90 } 91 92 static inline bool pde_has_proc_compat_ioctl(const struct proc_dir_entry *pde) 93 { 94 #ifdef CONFIG_COMPAT 95 return pde->flags & PROC_ENTRY_proc_compat_ioctl; 96 #else 97 return false; 98 #endif 99 } 100 101 extern struct kmem_cache *proc_dir_entry_cache; 102 void pde_free(struct proc_dir_entry *pde); 103 104 union proc_op { 105 int (*proc_get_link)(struct dentry *, struct path *); 106 int (*proc_show)(struct seq_file *m, 107 struct pid_namespace *ns, struct pid *pid, 108 struct task_struct *task); 109 const char *lsm; 110 }; 111 112 struct proc_inode { 113 struct pid *pid; 114 unsigned int fd; 115 union proc_op op; 116 struct proc_dir_entry *pde; 117 struct ctl_table_header *sysctl; 118 struct ctl_table *sysctl_entry; 119 struct hlist_node sibling_inodes; 120 const struct proc_ns_operations *ns_ops; 121 struct inode vfs_inode; 122 } __randomize_layout; 123 124 /* 125 * General functions 126 */ 127 static inline struct proc_inode *PROC_I(const struct inode *inode) 128 { 129 return container_of(inode, struct proc_inode, vfs_inode); 130 } 131 132 static inline struct proc_dir_entry *PDE(const struct inode *inode) 133 { 134 return PROC_I(inode)->pde; 135 } 136 137 static inline struct pid *proc_pid(const struct inode *inode) 138 { 139 return PROC_I(inode)->pid; 140 } 141 142 static inline struct task_struct *get_proc_task(const struct inode *inode) 143 { 144 return get_pid_task(proc_pid(inode), PIDTYPE_PID); 145 } 146 147 void task_dump_owner(struct task_struct *task, umode_t mode, 148 kuid_t *ruid, kgid_t *rgid); 149 150 unsigned name_to_int(const struct qstr *qstr); 151 /* 152 * Offset of the first process in the /proc root directory.. 153 */ 154 #define FIRST_PROCESS_ENTRY 256 155 156 /* Worst case buffer size needed for holding an integer. */ 157 #define PROC_NUMBUF 13 158 159 /* 160 * array.c 161 */ 162 extern const struct file_operations proc_tid_children_operations; 163 164 extern void proc_task_name(struct seq_file *m, struct task_struct *p, 165 bool escape); 166 extern int proc_tid_stat(struct seq_file *, struct pid_namespace *, 167 struct pid *, struct task_struct *); 168 extern int proc_tgid_stat(struct seq_file *, struct pid_namespace *, 169 struct pid *, struct task_struct *); 170 extern int proc_pid_status(struct seq_file *, struct pid_namespace *, 171 struct pid *, struct task_struct *); 172 extern int proc_pid_statm(struct seq_file *, struct pid_namespace *, 173 struct pid *, struct task_struct *); 174 175 /* 176 * base.c 177 */ 178 extern const struct dentry_operations pid_dentry_operations; 179 extern int pid_getattr(struct mnt_idmap *, const struct path *, 180 struct kstat *, u32, unsigned int); 181 extern int proc_setattr(struct mnt_idmap *, struct dentry *, 182 struct iattr *); 183 extern void proc_pid_evict_inode(struct proc_inode *); 184 extern struct inode *proc_pid_make_inode(struct super_block *, struct task_struct *, umode_t); 185 extern void pid_update_inode(struct task_struct *, struct inode *); 186 extern int pid_delete_dentry(const struct dentry *); 187 extern int proc_pid_readdir(struct file *, struct dir_context *); 188 struct dentry *proc_pid_lookup(struct dentry *, unsigned int); 189 extern loff_t mem_lseek(struct file *, loff_t, int); 190 191 /* Lookups */ 192 typedef struct dentry *instantiate_t(struct dentry *, 193 struct task_struct *, const void *); 194 bool proc_fill_cache(struct file *, struct dir_context *, const char *, unsigned int, 195 instantiate_t, struct task_struct *, const void *); 196 197 /* 198 * generic.c 199 */ 200 struct proc_dir_entry *proc_create_reg(const char *name, umode_t mode, 201 struct proc_dir_entry **parent, void *data); 202 struct proc_dir_entry *proc_register(struct proc_dir_entry *dir, 203 struct proc_dir_entry *dp); 204 extern struct dentry *proc_lookup(struct inode *, struct dentry *, unsigned int); 205 struct dentry *proc_lookup_de(struct inode *, struct dentry *, struct proc_dir_entry *); 206 extern int proc_readdir(struct file *, struct dir_context *); 207 int proc_readdir_de(struct file *, struct dir_context *, struct proc_dir_entry *); 208 209 static inline void pde_get(struct proc_dir_entry *pde) 210 { 211 refcount_inc(&pde->refcnt); 212 } 213 extern void pde_put(struct proc_dir_entry *); 214 215 static inline bool is_empty_pde(const struct proc_dir_entry *pde) 216 { 217 return S_ISDIR(pde->mode) && !pde->proc_iops; 218 } 219 extern ssize_t proc_simple_write(struct file *, const char __user *, size_t, loff_t *); 220 221 /* 222 * inode.c 223 */ 224 struct pde_opener { 225 struct list_head lh; 226 struct file *file; 227 bool closing; 228 struct completion *c; 229 } __randomize_layout; 230 extern const struct inode_operations proc_link_inode_operations; 231 extern const struct inode_operations proc_pid_link_inode_operations; 232 extern const struct super_operations proc_sops; 233 234 void proc_init_kmemcache(void); 235 void proc_invalidate_siblings_dcache(struct hlist_head *inodes, spinlock_t *lock); 236 void set_proc_pid_nlink(void); 237 extern struct inode *proc_get_inode(struct super_block *, struct proc_dir_entry *); 238 extern void proc_entry_rundown(struct proc_dir_entry *); 239 240 /* 241 * proc_namespaces.c 242 */ 243 extern const struct inode_operations proc_ns_dir_inode_operations; 244 extern const struct file_operations proc_ns_dir_operations; 245 246 /* 247 * proc_net.c 248 */ 249 extern const struct file_operations proc_net_operations; 250 extern const struct inode_operations proc_net_inode_operations; 251 252 #ifdef CONFIG_NET 253 extern int proc_net_init(void); 254 #else 255 static inline int proc_net_init(void) { return 0; } 256 #endif 257 258 /* 259 * proc_self.c 260 */ 261 extern int proc_setup_self(struct super_block *); 262 263 /* 264 * proc_thread_self.c 265 */ 266 extern int proc_setup_thread_self(struct super_block *); 267 extern void proc_thread_self_init(void); 268 269 /* 270 * proc_sysctl.c 271 */ 272 #ifdef CONFIG_PROC_SYSCTL 273 extern int proc_sys_init(void); 274 extern void proc_sys_evict_inode(struct inode *inode, 275 struct ctl_table_header *head); 276 #else 277 static inline void proc_sys_init(void) { } 278 static inline void proc_sys_evict_inode(struct inode *inode, 279 struct ctl_table_header *head) { } 280 #endif 281 282 /* 283 * proc_tty.c 284 */ 285 #ifdef CONFIG_TTY 286 extern void proc_tty_init(void); 287 #else 288 static inline void proc_tty_init(void) {} 289 #endif 290 291 /* 292 * root.c 293 */ 294 extern struct proc_dir_entry proc_root; 295 296 extern void proc_self_init(void); 297 298 /* 299 * task_[no]mmu.c 300 */ 301 struct mem_size_stats; 302 struct proc_maps_private { 303 struct inode *inode; 304 struct task_struct *task; 305 struct mm_struct *mm; 306 struct vma_iterator iter; 307 #ifdef CONFIG_NUMA 308 struct mempolicy *task_mempolicy; 309 #endif 310 } __randomize_layout; 311 312 struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode); 313 314 extern const struct file_operations proc_pid_maps_operations; 315 extern const struct file_operations proc_pid_numa_maps_operations; 316 extern const struct file_operations proc_pid_smaps_operations; 317 extern const struct file_operations proc_pid_smaps_rollup_operations; 318 extern const struct file_operations proc_clear_refs_operations; 319 extern const struct file_operations proc_pagemap_operations; 320 321 extern unsigned long task_vsize(struct mm_struct *); 322 extern unsigned long task_statm(struct mm_struct *, 323 unsigned long *, unsigned long *, 324 unsigned long *, unsigned long *); 325 extern void task_mem(struct seq_file *, struct mm_struct *); 326 327 extern const struct dentry_operations proc_net_dentry_ops; 328 static inline void pde_force_lookup(struct proc_dir_entry *pde) 329 { 330 /* /proc/net/ entries can be changed under us by setns(CLONE_NEWNET) */ 331 pde->proc_dops = &proc_net_dentry_ops; 332 } 333