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git.proxmox.com Git - mirror_ubuntu-jammy-kernel.git/blob - fs/readdir.c
4 * Copyright (C) 1995 Linus Torvalds
7 #include <linux/kernel.h>
8 #include <linux/module.h>
9 #include <linux/time.h>
11 #include <linux/errno.h>
12 #include <linux/stat.h>
13 #include <linux/file.h>
15 #include <linux/dirent.h>
16 #include <linux/security.h>
17 #include <linux/syscalls.h>
18 #include <linux/unistd.h>
20 #include <asm/uaccess.h>
22 int vfs_readdir(struct file
*file
, filldir_t filler
, void *buf
)
24 struct inode
*inode
= file
->f_path
.dentry
->d_inode
;
26 if (!file
->f_op
|| !file
->f_op
->readdir
)
29 res
= security_file_permission(file
, MAY_READ
);
33 res
= mutex_lock_killable(&inode
->i_mutex
);
38 if (!IS_DEADDIR(inode
)) {
39 res
= file
->f_op
->readdir(file
, buf
, filler
);
42 mutex_unlock(&inode
->i_mutex
);
47 EXPORT_SYMBOL(vfs_readdir
);
50 * Traditional linux readdir() handling..
52 * "count=1" is a special case, meaning that the buffer is one
53 * dirent-structure in size and that the code can't handle more
54 * anyway. Thus the special "fillonedir()" function for that
55 * case (the low-level handlers don't need to care about this).
57 #define NAME_OFFSET(de) ((int) ((de)->d_name - (char __user *) (de)))
59 #ifdef __ARCH_WANT_OLD_READDIR
61 struct old_linux_dirent
{
63 unsigned long d_offset
;
64 unsigned short d_namlen
;
68 struct readdir_callback
{
69 struct old_linux_dirent __user
* dirent
;
73 static int fillonedir(void * __buf
, const char * name
, int namlen
, loff_t offset
,
74 u64 ino
, unsigned int d_type
)
76 struct readdir_callback
* buf
= (struct readdir_callback
*) __buf
;
77 struct old_linux_dirent __user
* dirent
;
83 if (sizeof(d_ino
) < sizeof(ino
) && d_ino
!= ino
) {
84 buf
->result
= -EOVERFLOW
;
89 if (!access_ok(VERIFY_WRITE
, dirent
,
90 (unsigned long)(dirent
->d_name
+ namlen
+ 1) -
91 (unsigned long)dirent
))
93 if ( __put_user(d_ino
, &dirent
->d_ino
) ||
94 __put_user(offset
, &dirent
->d_offset
) ||
95 __put_user(namlen
, &dirent
->d_namlen
) ||
96 __copy_to_user(dirent
->d_name
, name
, namlen
) ||
97 __put_user(0, dirent
->d_name
+ namlen
))
101 buf
->result
= -EFAULT
;
105 asmlinkage
long old_readdir(unsigned int fd
, struct old_linux_dirent __user
* dirent
, unsigned int count
)
109 struct readdir_callback buf
;
119 error
= vfs_readdir(file
, fillonedir
, &buf
);
128 #endif /* __ARCH_WANT_OLD_READDIR */
131 * New, all-improved, singing, dancing, iBCS2-compliant getdents()
134 struct linux_dirent
{
137 unsigned short d_reclen
;
141 struct getdents_callback
{
142 struct linux_dirent __user
* current_dir
;
143 struct linux_dirent __user
* previous
;
148 static int filldir(void * __buf
, const char * name
, int namlen
, loff_t offset
,
149 u64 ino
, unsigned int d_type
)
151 struct linux_dirent __user
* dirent
;
152 struct getdents_callback
* buf
= (struct getdents_callback
*) __buf
;
154 int reclen
= ALIGN(NAME_OFFSET(dirent
) + namlen
+ 2, sizeof(long));
156 buf
->error
= -EINVAL
; /* only used if we fail.. */
157 if (reclen
> buf
->count
)
160 if (sizeof(d_ino
) < sizeof(ino
) && d_ino
!= ino
) {
161 buf
->error
= -EOVERFLOW
;
164 dirent
= buf
->previous
;
166 if (__put_user(offset
, &dirent
->d_off
))
169 dirent
= buf
->current_dir
;
170 if (__put_user(d_ino
, &dirent
->d_ino
))
172 if (__put_user(reclen
, &dirent
->d_reclen
))
174 if (copy_to_user(dirent
->d_name
, name
, namlen
))
176 if (__put_user(0, dirent
->d_name
+ namlen
))
178 if (__put_user(d_type
, (char __user
*) dirent
+ reclen
- 1))
180 buf
->previous
= dirent
;
181 dirent
= (void __user
*)dirent
+ reclen
;
182 buf
->current_dir
= dirent
;
183 buf
->count
-= reclen
;
186 buf
->error
= -EFAULT
;
190 asmlinkage
long sys_getdents(unsigned int fd
, struct linux_dirent __user
* dirent
, unsigned int count
)
193 struct linux_dirent __user
* lastdirent
;
194 struct getdents_callback buf
;
198 if (!access_ok(VERIFY_WRITE
, dirent
, count
))
206 buf
.current_dir
= dirent
;
211 error
= vfs_readdir(file
, filldir
, &buf
);
215 lastdirent
= buf
.previous
;
217 if (put_user(file
->f_pos
, &lastdirent
->d_off
))
220 error
= count
- buf
.count
;
229 struct getdents_callback64
{
230 struct linux_dirent64 __user
* current_dir
;
231 struct linux_dirent64 __user
* previous
;
236 static int filldir64(void * __buf
, const char * name
, int namlen
, loff_t offset
,
237 u64 ino
, unsigned int d_type
)
239 struct linux_dirent64 __user
*dirent
;
240 struct getdents_callback64
* buf
= (struct getdents_callback64
*) __buf
;
241 int reclen
= ALIGN(NAME_OFFSET(dirent
) + namlen
+ 1, sizeof(u64
));
243 buf
->error
= -EINVAL
; /* only used if we fail.. */
244 if (reclen
> buf
->count
)
246 dirent
= buf
->previous
;
248 if (__put_user(offset
, &dirent
->d_off
))
251 dirent
= buf
->current_dir
;
252 if (__put_user(ino
, &dirent
->d_ino
))
254 if (__put_user(0, &dirent
->d_off
))
256 if (__put_user(reclen
, &dirent
->d_reclen
))
258 if (__put_user(d_type
, &dirent
->d_type
))
260 if (copy_to_user(dirent
->d_name
, name
, namlen
))
262 if (__put_user(0, dirent
->d_name
+ namlen
))
264 buf
->previous
= dirent
;
265 dirent
= (void __user
*)dirent
+ reclen
;
266 buf
->current_dir
= dirent
;
267 buf
->count
-= reclen
;
270 buf
->error
= -EFAULT
;
274 asmlinkage
long sys_getdents64(unsigned int fd
, struct linux_dirent64 __user
* dirent
, unsigned int count
)
277 struct linux_dirent64 __user
* lastdirent
;
278 struct getdents_callback64 buf
;
282 if (!access_ok(VERIFY_WRITE
, dirent
, count
))
290 buf
.current_dir
= dirent
;
295 error
= vfs_readdir(file
, filldir64
, &buf
);
299 lastdirent
= buf
.previous
;
301 typeof(lastdirent
->d_off
) d_off
= file
->f_pos
;
303 if (__put_user(d_off
, &lastdirent
->d_off
))
305 error
= count
- buf
.count
;