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Commit | Line | Data |
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7ed1ee61 | 1 | #include <linux/syscalls.h> |
630d9c47 | 2 | #include <linux/export.h> |
7ed1ee61 AV |
3 | #include <linux/fs.h> |
4 | #include <linux/file.h> | |
365b1818 | 5 | #include <linux/mount.h> |
7ed1ee61 AV |
6 | #include <linux/namei.h> |
7 | #include <linux/statfs.h> | |
8 | #include <linux/security.h> | |
9 | #include <linux/uaccess.h> | |
4ada54ee | 10 | #include <linux/compat.h> |
cf31e70d | 11 | #include "internal.h" |
7ed1ee61 | 12 | |
365b1818 CH |
13 | static int flags_by_mnt(int mnt_flags) |
14 | { | |
15 | int flags = 0; | |
16 | ||
17 | if (mnt_flags & MNT_READONLY) | |
18 | flags |= ST_RDONLY; | |
19 | if (mnt_flags & MNT_NOSUID) | |
20 | flags |= ST_NOSUID; | |
21 | if (mnt_flags & MNT_NODEV) | |
22 | flags |= ST_NODEV; | |
23 | if (mnt_flags & MNT_NOEXEC) | |
24 | flags |= ST_NOEXEC; | |
25 | if (mnt_flags & MNT_NOATIME) | |
26 | flags |= ST_NOATIME; | |
27 | if (mnt_flags & MNT_NODIRATIME) | |
28 | flags |= ST_NODIRATIME; | |
29 | if (mnt_flags & MNT_RELATIME) | |
30 | flags |= ST_RELATIME; | |
31 | return flags; | |
32 | } | |
33 | ||
34 | static int flags_by_sb(int s_flags) | |
35 | { | |
36 | int flags = 0; | |
37 | if (s_flags & MS_SYNCHRONOUS) | |
38 | flags |= ST_SYNCHRONOUS; | |
39 | if (s_flags & MS_MANDLOCK) | |
40 | flags |= ST_MANDLOCK; | |
41 | return flags; | |
42 | } | |
43 | ||
44 | static int calculate_f_flags(struct vfsmount *mnt) | |
45 | { | |
46 | return ST_VALID | flags_by_mnt(mnt->mnt_flags) | | |
47 | flags_by_sb(mnt->mnt_sb->s_flags); | |
48 | } | |
49 | ||
cf31e70d | 50 | static int statfs_by_dentry(struct dentry *dentry, struct kstatfs *buf) |
7ed1ee61 | 51 | { |
ebabe9a9 CH |
52 | int retval; |
53 | ||
54 | if (!dentry->d_sb->s_op->statfs) | |
55 | return -ENOSYS; | |
56 | ||
57 | memset(buf, 0, sizeof(*buf)); | |
58 | retval = security_sb_statfs(dentry); | |
59 | if (retval) | |
60 | return retval; | |
61 | retval = dentry->d_sb->s_op->statfs(dentry, buf); | |
62 | if (retval == 0 && buf->f_frsize == 0) | |
63 | buf->f_frsize = buf->f_bsize; | |
7ed1ee61 AV |
64 | return retval; |
65 | } | |
66 | ||
f0bb5aaf | 67 | int vfs_statfs(const struct path *path, struct kstatfs *buf) |
ebabe9a9 | 68 | { |
365b1818 CH |
69 | int error; |
70 | ||
71 | error = statfs_by_dentry(path->dentry, buf); | |
72 | if (!error) | |
73 | buf->f_flags = calculate_f_flags(path->mnt); | |
74 | return error; | |
ebabe9a9 | 75 | } |
7ed1ee61 AV |
76 | EXPORT_SYMBOL(vfs_statfs); |
77 | ||
c8b91acc | 78 | int user_statfs(const char __user *pathname, struct kstatfs *st) |
7ed1ee61 | 79 | { |
c8b91acc | 80 | struct path path; |
96948fc6 JL |
81 | int error; |
82 | unsigned int lookup_flags = LOOKUP_FOLLOW|LOOKUP_AUTOMOUNT; | |
83 | retry: | |
84 | error = user_path_at(AT_FDCWD, pathname, lookup_flags, &path); | |
c8b91acc AV |
85 | if (!error) { |
86 | error = vfs_statfs(&path, st); | |
87 | path_put(&path); | |
96948fc6 JL |
88 | if (retry_estale(error, lookup_flags)) { |
89 | lookup_flags |= LOOKUP_REVAL; | |
90 | goto retry; | |
91 | } | |
c8b91acc AV |
92 | } |
93 | return error; | |
94 | } | |
7ed1ee61 | 95 | |
c8b91acc AV |
96 | int fd_statfs(int fd, struct kstatfs *st) |
97 | { | |
9d05746e | 98 | struct fd f = fdget_raw(fd); |
c8b91acc | 99 | int error = -EBADF; |
2903ff01 AV |
100 | if (f.file) { |
101 | error = vfs_statfs(&f.file->f_path, st); | |
102 | fdput(f); | |
c8b91acc AV |
103 | } |
104 | return error; | |
105 | } | |
7ed1ee61 | 106 | |
c8b91acc AV |
107 | static int do_statfs_native(struct kstatfs *st, struct statfs __user *p) |
108 | { | |
109 | struct statfs buf; | |
110 | ||
111 | if (sizeof(buf) == sizeof(*st)) | |
112 | memcpy(&buf, st, sizeof(*st)); | |
7ed1ee61 | 113 | else { |
c8b91acc AV |
114 | if (sizeof buf.f_blocks == 4) { |
115 | if ((st->f_blocks | st->f_bfree | st->f_bavail | | |
116 | st->f_bsize | st->f_frsize) & | |
7ed1ee61 AV |
117 | 0xffffffff00000000ULL) |
118 | return -EOVERFLOW; | |
119 | /* | |
120 | * f_files and f_ffree may be -1; it's okay to stuff | |
121 | * that into 32 bits | |
122 | */ | |
c8b91acc AV |
123 | if (st->f_files != -1 && |
124 | (st->f_files & 0xffffffff00000000ULL)) | |
7ed1ee61 | 125 | return -EOVERFLOW; |
c8b91acc AV |
126 | if (st->f_ffree != -1 && |
127 | (st->f_ffree & 0xffffffff00000000ULL)) | |
7ed1ee61 AV |
128 | return -EOVERFLOW; |
129 | } | |
130 | ||
c8b91acc AV |
131 | buf.f_type = st->f_type; |
132 | buf.f_bsize = st->f_bsize; | |
133 | buf.f_blocks = st->f_blocks; | |
134 | buf.f_bfree = st->f_bfree; | |
135 | buf.f_bavail = st->f_bavail; | |
136 | buf.f_files = st->f_files; | |
137 | buf.f_ffree = st->f_ffree; | |
138 | buf.f_fsid = st->f_fsid; | |
139 | buf.f_namelen = st->f_namelen; | |
140 | buf.f_frsize = st->f_frsize; | |
141 | buf.f_flags = st->f_flags; | |
142 | memset(buf.f_spare, 0, sizeof(buf.f_spare)); | |
7ed1ee61 | 143 | } |
c8b91acc AV |
144 | if (copy_to_user(p, &buf, sizeof(buf))) |
145 | return -EFAULT; | |
7ed1ee61 AV |
146 | return 0; |
147 | } | |
148 | ||
c8b91acc | 149 | static int do_statfs64(struct kstatfs *st, struct statfs64 __user *p) |
7ed1ee61 | 150 | { |
c8b91acc AV |
151 | struct statfs64 buf; |
152 | if (sizeof(buf) == sizeof(*st)) | |
153 | memcpy(&buf, st, sizeof(*st)); | |
7ed1ee61 | 154 | else { |
c8b91acc AV |
155 | buf.f_type = st->f_type; |
156 | buf.f_bsize = st->f_bsize; | |
157 | buf.f_blocks = st->f_blocks; | |
158 | buf.f_bfree = st->f_bfree; | |
159 | buf.f_bavail = st->f_bavail; | |
160 | buf.f_files = st->f_files; | |
161 | buf.f_ffree = st->f_ffree; | |
162 | buf.f_fsid = st->f_fsid; | |
163 | buf.f_namelen = st->f_namelen; | |
164 | buf.f_frsize = st->f_frsize; | |
165 | buf.f_flags = st->f_flags; | |
166 | memset(buf.f_spare, 0, sizeof(buf.f_spare)); | |
7ed1ee61 | 167 | } |
c8b91acc AV |
168 | if (copy_to_user(p, &buf, sizeof(buf))) |
169 | return -EFAULT; | |
7ed1ee61 AV |
170 | return 0; |
171 | } | |
172 | ||
173 | SYSCALL_DEFINE2(statfs, const char __user *, pathname, struct statfs __user *, buf) | |
174 | { | |
c8b91acc AV |
175 | struct kstatfs st; |
176 | int error = user_statfs(pathname, &st); | |
177 | if (!error) | |
178 | error = do_statfs_native(&st, buf); | |
7ed1ee61 AV |
179 | return error; |
180 | } | |
181 | ||
182 | SYSCALL_DEFINE3(statfs64, const char __user *, pathname, size_t, sz, struct statfs64 __user *, buf) | |
183 | { | |
c8b91acc AV |
184 | struct kstatfs st; |
185 | int error; | |
7ed1ee61 AV |
186 | if (sz != sizeof(*buf)) |
187 | return -EINVAL; | |
c8b91acc AV |
188 | error = user_statfs(pathname, &st); |
189 | if (!error) | |
190 | error = do_statfs64(&st, buf); | |
7ed1ee61 AV |
191 | return error; |
192 | } | |
193 | ||
194 | SYSCALL_DEFINE2(fstatfs, unsigned int, fd, struct statfs __user *, buf) | |
195 | { | |
c8b91acc AV |
196 | struct kstatfs st; |
197 | int error = fd_statfs(fd, &st); | |
198 | if (!error) | |
199 | error = do_statfs_native(&st, buf); | |
7ed1ee61 AV |
200 | return error; |
201 | } | |
202 | ||
203 | SYSCALL_DEFINE3(fstatfs64, unsigned int, fd, size_t, sz, struct statfs64 __user *, buf) | |
204 | { | |
c8b91acc | 205 | struct kstatfs st; |
7ed1ee61 AV |
206 | int error; |
207 | ||
208 | if (sz != sizeof(*buf)) | |
209 | return -EINVAL; | |
210 | ||
c8b91acc AV |
211 | error = fd_statfs(fd, &st); |
212 | if (!error) | |
213 | error = do_statfs64(&st, buf); | |
7ed1ee61 AV |
214 | return error; |
215 | } | |
216 | ||
cf31e70d | 217 | int vfs_ustat(dev_t dev, struct kstatfs *sbuf) |
7ed1ee61 | 218 | { |
cf31e70d | 219 | struct super_block *s = user_get_super(dev); |
7ed1ee61 | 220 | int err; |
7ed1ee61 AV |
221 | if (!s) |
222 | return -EINVAL; | |
223 | ||
cf31e70d | 224 | err = statfs_by_dentry(s->s_root, sbuf); |
7ed1ee61 | 225 | drop_super(s); |
cf31e70d AV |
226 | return err; |
227 | } | |
228 | ||
229 | SYSCALL_DEFINE2(ustat, unsigned, dev, struct ustat __user *, ubuf) | |
230 | { | |
231 | struct ustat tmp; | |
232 | struct kstatfs sbuf; | |
233 | int err = vfs_ustat(new_decode_dev(dev), &sbuf); | |
7ed1ee61 AV |
234 | if (err) |
235 | return err; | |
236 | ||
237 | memset(&tmp,0,sizeof(struct ustat)); | |
238 | tmp.f_tfree = sbuf.f_bfree; | |
239 | tmp.f_tinode = sbuf.f_ffree; | |
240 | ||
241 | return copy_to_user(ubuf, &tmp, sizeof(struct ustat)) ? -EFAULT : 0; | |
242 | } | |
4ada54ee AV |
243 | |
244 | #ifdef CONFIG_COMPAT | |
245 | static int put_compat_statfs(struct compat_statfs __user *ubuf, struct kstatfs *kbuf) | |
246 | { | |
ae2a9762 | 247 | struct compat_statfs buf; |
4ada54ee AV |
248 | if (sizeof ubuf->f_blocks == 4) { |
249 | if ((kbuf->f_blocks | kbuf->f_bfree | kbuf->f_bavail | | |
250 | kbuf->f_bsize | kbuf->f_frsize) & 0xffffffff00000000ULL) | |
251 | return -EOVERFLOW; | |
252 | /* f_files and f_ffree may be -1; it's okay | |
253 | * to stuff that into 32 bits */ | |
254 | if (kbuf->f_files != 0xffffffffffffffffULL | |
255 | && (kbuf->f_files & 0xffffffff00000000ULL)) | |
256 | return -EOVERFLOW; | |
257 | if (kbuf->f_ffree != 0xffffffffffffffffULL | |
258 | && (kbuf->f_ffree & 0xffffffff00000000ULL)) | |
259 | return -EOVERFLOW; | |
260 | } | |
ae2a9762 AV |
261 | memset(&buf, 0, sizeof(struct compat_statfs)); |
262 | buf.f_type = kbuf->f_type; | |
263 | buf.f_bsize = kbuf->f_bsize; | |
264 | buf.f_blocks = kbuf->f_blocks; | |
265 | buf.f_bfree = kbuf->f_bfree; | |
266 | buf.f_bavail = kbuf->f_bavail; | |
267 | buf.f_files = kbuf->f_files; | |
268 | buf.f_ffree = kbuf->f_ffree; | |
269 | buf.f_namelen = kbuf->f_namelen; | |
270 | buf.f_fsid.val[0] = kbuf->f_fsid.val[0]; | |
271 | buf.f_fsid.val[1] = kbuf->f_fsid.val[1]; | |
272 | buf.f_frsize = kbuf->f_frsize; | |
273 | buf.f_flags = kbuf->f_flags; | |
274 | if (copy_to_user(ubuf, &buf, sizeof(struct compat_statfs))) | |
4ada54ee AV |
275 | return -EFAULT; |
276 | return 0; | |
277 | } | |
278 | ||
279 | /* | |
280 | * The following statfs calls are copies of code from fs/statfs.c and | |
281 | * should be checked against those from time to time | |
282 | */ | |
283 | COMPAT_SYSCALL_DEFINE2(statfs, const char __user *, pathname, struct compat_statfs __user *, buf) | |
284 | { | |
285 | struct kstatfs tmp; | |
286 | int error = user_statfs(pathname, &tmp); | |
287 | if (!error) | |
288 | error = put_compat_statfs(buf, &tmp); | |
289 | return error; | |
290 | } | |
291 | ||
292 | COMPAT_SYSCALL_DEFINE2(fstatfs, unsigned int, fd, struct compat_statfs __user *, buf) | |
293 | { | |
294 | struct kstatfs tmp; | |
295 | int error = fd_statfs(fd, &tmp); | |
296 | if (!error) | |
297 | error = put_compat_statfs(buf, &tmp); | |
298 | return error; | |
299 | } | |
300 | ||
301 | static int put_compat_statfs64(struct compat_statfs64 __user *ubuf, struct kstatfs *kbuf) | |
302 | { | |
ae2a9762 | 303 | struct compat_statfs64 buf; |
4ada54ee AV |
304 | if (sizeof(ubuf->f_bsize) == 4) { |
305 | if ((kbuf->f_type | kbuf->f_bsize | kbuf->f_namelen | | |
306 | kbuf->f_frsize | kbuf->f_flags) & 0xffffffff00000000ULL) | |
307 | return -EOVERFLOW; | |
308 | /* f_files and f_ffree may be -1; it's okay | |
309 | * to stuff that into 32 bits */ | |
310 | if (kbuf->f_files != 0xffffffffffffffffULL | |
311 | && (kbuf->f_files & 0xffffffff00000000ULL)) | |
312 | return -EOVERFLOW; | |
313 | if (kbuf->f_ffree != 0xffffffffffffffffULL | |
314 | && (kbuf->f_ffree & 0xffffffff00000000ULL)) | |
315 | return -EOVERFLOW; | |
316 | } | |
ae2a9762 AV |
317 | memset(&buf, 0, sizeof(struct compat_statfs64)); |
318 | buf.f_type = kbuf->f_type; | |
319 | buf.f_bsize = kbuf->f_bsize; | |
320 | buf.f_blocks = kbuf->f_blocks; | |
321 | buf.f_bfree = kbuf->f_bfree; | |
322 | buf.f_bavail = kbuf->f_bavail; | |
323 | buf.f_files = kbuf->f_files; | |
324 | buf.f_ffree = kbuf->f_ffree; | |
325 | buf.f_namelen = kbuf->f_namelen; | |
326 | buf.f_fsid.val[0] = kbuf->f_fsid.val[0]; | |
327 | buf.f_fsid.val[1] = kbuf->f_fsid.val[1]; | |
328 | buf.f_frsize = kbuf->f_frsize; | |
329 | buf.f_flags = kbuf->f_flags; | |
330 | if (copy_to_user(ubuf, &buf, sizeof(struct compat_statfs64))) | |
4ada54ee AV |
331 | return -EFAULT; |
332 | return 0; | |
333 | } | |
334 | ||
335 | COMPAT_SYSCALL_DEFINE3(statfs64, const char __user *, pathname, compat_size_t, sz, struct compat_statfs64 __user *, buf) | |
336 | { | |
337 | struct kstatfs tmp; | |
338 | int error; | |
339 | ||
340 | if (sz != sizeof(*buf)) | |
341 | return -EINVAL; | |
342 | ||
343 | error = user_statfs(pathname, &tmp); | |
344 | if (!error) | |
345 | error = put_compat_statfs64(buf, &tmp); | |
346 | return error; | |
347 | } | |
348 | ||
349 | COMPAT_SYSCALL_DEFINE3(fstatfs64, unsigned int, fd, compat_size_t, sz, struct compat_statfs64 __user *, buf) | |
350 | { | |
351 | struct kstatfs tmp; | |
352 | int error; | |
353 | ||
354 | if (sz != sizeof(*buf)) | |
355 | return -EINVAL; | |
356 | ||
357 | error = fd_statfs(fd, &tmp); | |
358 | if (!error) | |
359 | error = put_compat_statfs64(buf, &tmp); | |
360 | return error; | |
361 | } | |
362 | ||
363 | /* | |
364 | * This is a copy of sys_ustat, just dealing with a structure layout. | |
365 | * Given how simple this syscall is that apporach is more maintainable | |
366 | * than the various conversion hacks. | |
367 | */ | |
368 | COMPAT_SYSCALL_DEFINE2(ustat, unsigned, dev, struct compat_ustat __user *, u) | |
369 | { | |
370 | struct compat_ustat tmp; | |
371 | struct kstatfs sbuf; | |
372 | int err = vfs_ustat(new_decode_dev(dev), &sbuf); | |
373 | if (err) | |
374 | return err; | |
375 | ||
376 | memset(&tmp, 0, sizeof(struct compat_ustat)); | |
377 | tmp.f_tfree = sbuf.f_bfree; | |
378 | tmp.f_tinode = sbuf.f_ffree; | |
379 | if (copy_to_user(u, &tmp, sizeof(struct compat_ustat))) | |
380 | return -EFAULT; | |
381 | return 0; | |
382 | } | |
383 | #endif |