Line data Source code
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 0 : return pde->flags & PROC_ENTRY_PERMANENT;
80 : }
81 :
82 : static inline void pde_make_permanent(struct proc_dir_entry *pde)
83 : {
84 7 : 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 1 : 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 0 : return PROC_I(inode)->pde;
121 : }
122 :
123 : static inline struct pid *proc_pid(const struct inode *inode)
124 : {
125 0 : return PROC_I(inode)->pid;
126 : }
127 :
128 : static inline struct task_struct *get_proc_task(const struct inode *inode)
129 : {
130 0 : 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 2 : 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 : {
203 180 : 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 0 : pde->proc_dops = &proc_net_dentry_ops;
320 : }
|