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 const struct file_operations *proc_fops;
43 const struct dentry_operations *proc_dops;
44 union {
45 const struct seq_operations *seq_ops;
46 int (*single_show)(struct seq_file *, void *);
47 };
48 proc_write_t write;
49 void *data;
50 unsigned int state_size;
51 unsigned int low_ino;
52 nlink_t nlink;
53 kuid_t uid;
54 kgid_t gid;
55 loff_t size;
56 struct proc_dir_entry *parent;
57 struct rb_root subdir;
58 struct rb_node subdir_node;
59 char *name;
60 umode_t mode;
61 u8 namelen;
62 char inline_name[];
63 } __randomize_layout;
64
65 #define SIZEOF_PDE ( \
66 sizeof(struct proc_dir_entry) < 128 ? 128 : \
67 sizeof(struct proc_dir_entry) < 192 ? 192 : \
68 sizeof(struct proc_dir_entry) < 256 ? 256 : \
69 sizeof(struct proc_dir_entry) < 512 ? 512 : \
70 0)
71 #define SIZEOF_PDE_INLINE_NAME (SIZEOF_PDE - sizeof(struct proc_dir_entry))
72
73 extern struct kmem_cache *proc_dir_entry_cache;
74 void pde_free(struct proc_dir_entry *pde);
75
76 union proc_op {
77 int (*proc_get_link)(struct dentry *, struct path *);
78 int (*proc_show)(struct seq_file *m,
79 struct pid_namespace *ns, struct pid *pid,
80 struct task_struct *task);
81 const char *lsm;
82 };
83
84 struct proc_inode {
85 struct pid *pid;
86 unsigned int fd;
87 union proc_op op;
88 struct proc_dir_entry *pde;
89 struct ctl_table_header *sysctl;
90 struct ctl_table *sysctl_entry;
91 struct hlist_node sysctl_inodes;
92 const struct proc_ns_operations *ns_ops;
93 struct inode vfs_inode;
94 } __randomize_layout;
95
96 /*
97 * General functions
98 */
PROC_I(const struct inode * inode)99 static inline struct proc_inode *PROC_I(const struct inode *inode)
100 {
101 return container_of(inode, struct proc_inode, vfs_inode);
102 }
103
PDE(const struct inode * inode)104 static inline struct proc_dir_entry *PDE(const struct inode *inode)
105 {
106 return PROC_I(inode)->pde;
107 }
108
__PDE_DATA(const struct inode * inode)109 static inline void *__PDE_DATA(const struct inode *inode)
110 {
111 return PDE(inode)->data;
112 }
113
proc_pid(const struct inode * inode)114 static inline struct pid *proc_pid(const struct inode *inode)
115 {
116 return PROC_I(inode)->pid;
117 }
118
get_proc_task(const struct inode * inode)119 static inline struct task_struct *get_proc_task(const struct inode *inode)
120 {
121 return get_pid_task(proc_pid(inode), PIDTYPE_PID);
122 }
123
124 void task_dump_owner(struct task_struct *task, umode_t mode,
125 kuid_t *ruid, kgid_t *rgid);
126
127 unsigned name_to_int(const struct qstr *qstr);
128 /*
129 * Offset of the first process in the /proc root directory..
130 */
131 #define FIRST_PROCESS_ENTRY 256
132
133 /* Worst case buffer size needed for holding an integer. */
134 #define PROC_NUMBUF 13
135
136 /*
137 * array.c
138 */
139 extern const struct file_operations proc_tid_children_operations;
140
141 extern void proc_task_name(struct seq_file *m, struct task_struct *p,
142 bool escape);
143 extern int proc_tid_stat(struct seq_file *, struct pid_namespace *,
144 struct pid *, struct task_struct *);
145 extern int proc_tgid_stat(struct seq_file *, struct pid_namespace *,
146 struct pid *, struct task_struct *);
147 extern int proc_pid_status(struct seq_file *, struct pid_namespace *,
148 struct pid *, struct task_struct *);
149 extern int proc_pid_statm(struct seq_file *, struct pid_namespace *,
150 struct pid *, struct task_struct *);
151
152 /*
153 * base.c
154 */
155 extern const struct dentry_operations pid_dentry_operations;
156 extern int pid_getattr(const struct path *, struct kstat *, u32, unsigned int);
157 extern int proc_setattr(struct dentry *, struct iattr *);
158 extern struct inode *proc_pid_make_inode(struct super_block *, struct task_struct *, umode_t);
159 extern void pid_update_inode(struct task_struct *, struct inode *);
160 extern int pid_delete_dentry(const struct dentry *);
161 extern int proc_pid_readdir(struct file *, struct dir_context *);
162 struct dentry *proc_pid_lookup(struct dentry *, unsigned int);
163 extern loff_t mem_lseek(struct file *, loff_t, int);
164
165 /* Lookups */
166 typedef struct dentry *instantiate_t(struct dentry *,
167 struct task_struct *, const void *);
168 bool proc_fill_cache(struct file *, struct dir_context *, const char *, unsigned int,
169 instantiate_t, struct task_struct *, const void *);
170
171 /*
172 * generic.c
173 */
174 struct proc_dir_entry *proc_create_reg(const char *name, umode_t mode,
175 struct proc_dir_entry **parent, void *data);
176 struct proc_dir_entry *proc_register(struct proc_dir_entry *dir,
177 struct proc_dir_entry *dp);
178 extern struct dentry *proc_lookup(struct inode *, struct dentry *, unsigned int);
179 struct dentry *proc_lookup_de(struct inode *, struct dentry *, struct proc_dir_entry *);
180 extern int proc_readdir(struct file *, struct dir_context *);
181 int proc_readdir_de(struct file *, struct dir_context *, struct proc_dir_entry *);
182
pde_get(struct proc_dir_entry * pde)183 static inline struct proc_dir_entry *pde_get(struct proc_dir_entry *pde)
184 {
185 refcount_inc(&pde->refcnt);
186 return pde;
187 }
188 extern void pde_put(struct proc_dir_entry *);
189
is_empty_pde(const struct proc_dir_entry * pde)190 static inline bool is_empty_pde(const struct proc_dir_entry *pde)
191 {
192 return S_ISDIR(pde->mode) && !pde->proc_iops;
193 }
194 extern ssize_t proc_simple_write(struct file *, const char __user *, size_t, loff_t *);
195
196 /*
197 * inode.c
198 */
199 struct pde_opener {
200 struct file *file;
201 struct list_head lh;
202 bool closing;
203 struct completion *c;
204 } __randomize_layout;
205 extern const struct inode_operations proc_link_inode_operations;
206 extern const struct inode_operations proc_pid_link_inode_operations;
207 extern const struct super_operations proc_sops;
208
209 void proc_init_kmemcache(void);
210 void set_proc_pid_nlink(void);
211 extern struct inode *proc_get_inode(struct super_block *, struct proc_dir_entry *);
212 extern void proc_entry_rundown(struct proc_dir_entry *);
213
214 /*
215 * proc_namespaces.c
216 */
217 extern const struct inode_operations proc_ns_dir_inode_operations;
218 extern const struct file_operations proc_ns_dir_operations;
219
220 /*
221 * proc_net.c
222 */
223 extern const struct file_operations proc_net_operations;
224 extern const struct inode_operations proc_net_inode_operations;
225
226 #ifdef CONFIG_NET
227 extern int proc_net_init(void);
228 #else
proc_net_init(void)229 static inline int proc_net_init(void) { return 0; }
230 #endif
231
232 /*
233 * proc_self.c
234 */
235 extern int proc_setup_self(struct super_block *);
236
237 /*
238 * proc_thread_self.c
239 */
240 extern int proc_setup_thread_self(struct super_block *);
241 extern void proc_thread_self_init(void);
242
243 /*
244 * proc_sysctl.c
245 */
246 #ifdef CONFIG_PROC_SYSCTL
247 extern int proc_sys_init(void);
248 extern void proc_sys_evict_inode(struct inode *inode,
249 struct ctl_table_header *head);
250 #else
proc_sys_init(void)251 static inline void proc_sys_init(void) { }
proc_sys_evict_inode(struct inode * inode,struct ctl_table_header * head)252 static inline void proc_sys_evict_inode(struct inode *inode,
253 struct ctl_table_header *head) { }
254 #endif
255
256 /*
257 * uid.c
258 */
259 #ifdef CONFIG_PROC_UID
260 extern int proc_uid_init(void);
261 #else
proc_uid_init(void)262 static inline void proc_uid_init(void) { }
263 #endif
264
265 /*
266 * proc_tty.c
267 */
268 #ifdef CONFIG_TTY
269 extern void proc_tty_init(void);
270 #else
proc_tty_init(void)271 static inline void proc_tty_init(void) {}
272 #endif
273
274 /*
275 * root.c
276 */
277 extern struct proc_dir_entry proc_root;
278
279 extern void proc_self_init(void);
280
281 /*
282 * task_[no]mmu.c
283 */
284 struct mem_size_stats;
285 struct proc_maps_private {
286 struct inode *inode;
287 struct task_struct *task;
288 struct mm_struct *mm;
289 #ifdef CONFIG_MMU
290 struct vm_area_struct *tail_vma;
291 #endif
292 #ifdef CONFIG_NUMA
293 struct mempolicy *task_mempolicy;
294 #endif
295 } __randomize_layout;
296
297 struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode);
298
299 extern const struct file_operations proc_pid_maps_operations;
300 extern const struct file_operations proc_pid_numa_maps_operations;
301 extern const struct file_operations proc_pid_smaps_operations;
302 extern const struct file_operations proc_pid_smaps_rollup_operations;
303 extern const struct file_operations proc_clear_refs_operations;
304 extern const struct file_operations proc_pagemap_operations;
305
306 extern unsigned long task_vsize(struct mm_struct *);
307 extern unsigned long task_statm(struct mm_struct *,
308 unsigned long *, unsigned long *,
309 unsigned long *, unsigned long *);
310 extern void task_mem(struct seq_file *, struct mm_struct *);
311