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