1 // SPDX-License-Identifier: GPL-2.0 <<
2 #include <linux/syscalls.h> 1 #include <linux/syscalls.h>
3 #include <linux/export.h> 2 #include <linux/export.h>
4 #include <linux/fs.h> 3 #include <linux/fs.h>
5 #include <linux/file.h> 4 #include <linux/file.h>
6 #include <linux/mount.h> 5 #include <linux/mount.h>
7 #include <linux/namei.h> 6 #include <linux/namei.h>
8 #include <linux/statfs.h> 7 #include <linux/statfs.h>
9 #include <linux/security.h> 8 #include <linux/security.h>
10 #include <linux/uaccess.h> 9 #include <linux/uaccess.h>
11 #include <linux/compat.h> <<
12 #include "internal.h" 10 #include "internal.h"
13 11
14 static int flags_by_mnt(int mnt_flags) 12 static int flags_by_mnt(int mnt_flags)
15 { 13 {
16 int flags = 0; 14 int flags = 0;
17 15
18 if (mnt_flags & MNT_READONLY) 16 if (mnt_flags & MNT_READONLY)
19 flags |= ST_RDONLY; 17 flags |= ST_RDONLY;
20 if (mnt_flags & MNT_NOSUID) 18 if (mnt_flags & MNT_NOSUID)
21 flags |= ST_NOSUID; 19 flags |= ST_NOSUID;
22 if (mnt_flags & MNT_NODEV) 20 if (mnt_flags & MNT_NODEV)
23 flags |= ST_NODEV; 21 flags |= ST_NODEV;
24 if (mnt_flags & MNT_NOEXEC) 22 if (mnt_flags & MNT_NOEXEC)
25 flags |= ST_NOEXEC; 23 flags |= ST_NOEXEC;
26 if (mnt_flags & MNT_NOATIME) 24 if (mnt_flags & MNT_NOATIME)
27 flags |= ST_NOATIME; 25 flags |= ST_NOATIME;
28 if (mnt_flags & MNT_NODIRATIME) 26 if (mnt_flags & MNT_NODIRATIME)
29 flags |= ST_NODIRATIME; 27 flags |= ST_NODIRATIME;
30 if (mnt_flags & MNT_RELATIME) 28 if (mnt_flags & MNT_RELATIME)
31 flags |= ST_RELATIME; 29 flags |= ST_RELATIME;
32 if (mnt_flags & MNT_NOSYMFOLLOW) <<
33 flags |= ST_NOSYMFOLLOW; <<
34 return flags; 30 return flags;
35 } 31 }
36 32
37 static int flags_by_sb(int s_flags) 33 static int flags_by_sb(int s_flags)
38 { 34 {
39 int flags = 0; 35 int flags = 0;
40 if (s_flags & SB_SYNCHRONOUS) !! 36 if (s_flags & MS_SYNCHRONOUS)
41 flags |= ST_SYNCHRONOUS; 37 flags |= ST_SYNCHRONOUS;
42 if (s_flags & SB_MANDLOCK) !! 38 if (s_flags & MS_MANDLOCK)
43 flags |= ST_MANDLOCK; 39 flags |= ST_MANDLOCK;
44 if (s_flags & SB_RDONLY) <<
45 flags |= ST_RDONLY; <<
46 return flags; 40 return flags;
47 } 41 }
48 42
49 static int calculate_f_flags(struct vfsmount * 43 static int calculate_f_flags(struct vfsmount *mnt)
50 { 44 {
51 return ST_VALID | flags_by_mnt(mnt->mn 45 return ST_VALID | flags_by_mnt(mnt->mnt_flags) |
52 flags_by_sb(mnt->mnt_sb->s_fla 46 flags_by_sb(mnt->mnt_sb->s_flags);
53 } 47 }
54 48
55 static int statfs_by_dentry(struct dentry *den 49 static int statfs_by_dentry(struct dentry *dentry, struct kstatfs *buf)
56 { 50 {
57 int retval; 51 int retval;
58 52
59 if (!dentry->d_sb->s_op->statfs) 53 if (!dentry->d_sb->s_op->statfs)
60 return -ENOSYS; 54 return -ENOSYS;
61 55
62 memset(buf, 0, sizeof(*buf)); 56 memset(buf, 0, sizeof(*buf));
63 retval = security_sb_statfs(dentry); 57 retval = security_sb_statfs(dentry);
64 if (retval) 58 if (retval)
65 return retval; 59 return retval;
66 retval = dentry->d_sb->s_op->statfs(de 60 retval = dentry->d_sb->s_op->statfs(dentry, buf);
67 if (retval == 0 && buf->f_frsize == 0) 61 if (retval == 0 && buf->f_frsize == 0)
68 buf->f_frsize = buf->f_bsize; 62 buf->f_frsize = buf->f_bsize;
69 return retval; 63 return retval;
70 } 64 }
71 65
72 int vfs_get_fsid(struct dentry *dentry, __kern !! 66 int vfs_statfs(struct path *path, struct kstatfs *buf)
73 { <<
74 struct kstatfs st; <<
75 int error; <<
76 <<
77 error = statfs_by_dentry(dentry, &st); <<
78 if (error) <<
79 return error; <<
80 <<
81 *fsid = st.f_fsid; <<
82 return 0; <<
83 } <<
84 EXPORT_SYMBOL(vfs_get_fsid); <<
85 <<
86 int vfs_statfs(const struct path *path, struct <<
87 { 67 {
88 int error; 68 int error;
89 69
90 error = statfs_by_dentry(path->dentry, 70 error = statfs_by_dentry(path->dentry, buf);
91 if (!error) 71 if (!error)
92 buf->f_flags = calculate_f_fla 72 buf->f_flags = calculate_f_flags(path->mnt);
93 return error; 73 return error;
94 } 74 }
95 EXPORT_SYMBOL(vfs_statfs); 75 EXPORT_SYMBOL(vfs_statfs);
96 76
97 int user_statfs(const char __user *pathname, s 77 int user_statfs(const char __user *pathname, struct kstatfs *st)
98 { 78 {
99 struct path path; 79 struct path path;
100 int error; 80 int error;
101 unsigned int lookup_flags = LOOKUP_FOL 81 unsigned int lookup_flags = LOOKUP_FOLLOW|LOOKUP_AUTOMOUNT;
102 retry: 82 retry:
103 error = user_path_at(AT_FDCWD, pathnam 83 error = user_path_at(AT_FDCWD, pathname, lookup_flags, &path);
104 if (!error) { 84 if (!error) {
105 error = vfs_statfs(&path, st); 85 error = vfs_statfs(&path, st);
106 path_put(&path); 86 path_put(&path);
107 if (retry_estale(error, lookup 87 if (retry_estale(error, lookup_flags)) {
108 lookup_flags |= LOOKUP 88 lookup_flags |= LOOKUP_REVAL;
109 goto retry; 89 goto retry;
110 } 90 }
111 } 91 }
112 return error; 92 return error;
113 } 93 }
114 94
115 int fd_statfs(int fd, struct kstatfs *st) 95 int fd_statfs(int fd, struct kstatfs *st)
116 { 96 {
117 struct fd f = fdget_raw(fd); 97 struct fd f = fdget_raw(fd);
118 int error = -EBADF; 98 int error = -EBADF;
119 if (f.file) { 99 if (f.file) {
120 error = vfs_statfs(&f.file->f_ 100 error = vfs_statfs(&f.file->f_path, st);
121 fdput(f); 101 fdput(f);
122 } 102 }
123 return error; 103 return error;
124 } 104 }
125 105
126 static int do_statfs_native(struct kstatfs *st 106 static int do_statfs_native(struct kstatfs *st, struct statfs __user *p)
127 { 107 {
128 struct statfs buf; 108 struct statfs buf;
129 109
130 if (sizeof(buf) == sizeof(*st)) 110 if (sizeof(buf) == sizeof(*st))
131 memcpy(&buf, st, sizeof(*st)); 111 memcpy(&buf, st, sizeof(*st));
132 else { 112 else {
133 memset(&buf, 0, sizeof(buf)); <<
134 if (sizeof buf.f_blocks == 4) 113 if (sizeof buf.f_blocks == 4) {
135 if ((st->f_blocks | st 114 if ((st->f_blocks | st->f_bfree | st->f_bavail |
136 st->f_bsize | st- 115 st->f_bsize | st->f_frsize) &
137 0xffffffff00000000 116 0xffffffff00000000ULL)
138 return -EOVERF 117 return -EOVERFLOW;
139 /* 118 /*
140 * f_files and f_ffree 119 * f_files and f_ffree may be -1; it's okay to stuff
141 * that into 32 bits 120 * that into 32 bits
142 */ 121 */
143 if (st->f_files != -1 122 if (st->f_files != -1 &&
144 (st->f_files & 0xf 123 (st->f_files & 0xffffffff00000000ULL))
145 return -EOVERF 124 return -EOVERFLOW;
146 if (st->f_ffree != -1 125 if (st->f_ffree != -1 &&
147 (st->f_ffree & 0xf 126 (st->f_ffree & 0xffffffff00000000ULL))
148 return -EOVERF 127 return -EOVERFLOW;
149 } 128 }
150 129
151 buf.f_type = st->f_type; 130 buf.f_type = st->f_type;
152 buf.f_bsize = st->f_bsize; 131 buf.f_bsize = st->f_bsize;
153 buf.f_blocks = st->f_blocks; 132 buf.f_blocks = st->f_blocks;
154 buf.f_bfree = st->f_bfree; 133 buf.f_bfree = st->f_bfree;
155 buf.f_bavail = st->f_bavail; 134 buf.f_bavail = st->f_bavail;
156 buf.f_files = st->f_files; 135 buf.f_files = st->f_files;
157 buf.f_ffree = st->f_ffree; 136 buf.f_ffree = st->f_ffree;
158 buf.f_fsid = st->f_fsid; 137 buf.f_fsid = st->f_fsid;
159 buf.f_namelen = st->f_namelen; 138 buf.f_namelen = st->f_namelen;
160 buf.f_frsize = st->f_frsize; 139 buf.f_frsize = st->f_frsize;
161 buf.f_flags = st->f_flags; 140 buf.f_flags = st->f_flags;
>> 141 memset(buf.f_spare, 0, sizeof(buf.f_spare));
162 } 142 }
163 if (copy_to_user(p, &buf, sizeof(buf)) 143 if (copy_to_user(p, &buf, sizeof(buf)))
164 return -EFAULT; 144 return -EFAULT;
165 return 0; 145 return 0;
166 } 146 }
167 147
168 static int do_statfs64(struct kstatfs *st, str 148 static int do_statfs64(struct kstatfs *st, struct statfs64 __user *p)
169 { 149 {
170 struct statfs64 buf; 150 struct statfs64 buf;
171 if (sizeof(buf) == sizeof(*st)) 151 if (sizeof(buf) == sizeof(*st))
172 memcpy(&buf, st, sizeof(*st)); 152 memcpy(&buf, st, sizeof(*st));
173 else { 153 else {
174 memset(&buf, 0, sizeof(buf)); <<
175 buf.f_type = st->f_type; 154 buf.f_type = st->f_type;
176 buf.f_bsize = st->f_bsize; 155 buf.f_bsize = st->f_bsize;
177 buf.f_blocks = st->f_blocks; 156 buf.f_blocks = st->f_blocks;
178 buf.f_bfree = st->f_bfree; 157 buf.f_bfree = st->f_bfree;
179 buf.f_bavail = st->f_bavail; 158 buf.f_bavail = st->f_bavail;
180 buf.f_files = st->f_files; 159 buf.f_files = st->f_files;
181 buf.f_ffree = st->f_ffree; 160 buf.f_ffree = st->f_ffree;
182 buf.f_fsid = st->f_fsid; 161 buf.f_fsid = st->f_fsid;
183 buf.f_namelen = st->f_namelen; 162 buf.f_namelen = st->f_namelen;
184 buf.f_frsize = st->f_frsize; 163 buf.f_frsize = st->f_frsize;
185 buf.f_flags = st->f_flags; 164 buf.f_flags = st->f_flags;
>> 165 memset(buf.f_spare, 0, sizeof(buf.f_spare));
186 } 166 }
187 if (copy_to_user(p, &buf, sizeof(buf)) 167 if (copy_to_user(p, &buf, sizeof(buf)))
188 return -EFAULT; 168 return -EFAULT;
189 return 0; 169 return 0;
190 } 170 }
191 171
192 SYSCALL_DEFINE2(statfs, const char __user *, p 172 SYSCALL_DEFINE2(statfs, const char __user *, pathname, struct statfs __user *, buf)
193 { 173 {
194 struct kstatfs st; 174 struct kstatfs st;
195 int error = user_statfs(pathname, &st) 175 int error = user_statfs(pathname, &st);
196 if (!error) 176 if (!error)
197 error = do_statfs_native(&st, 177 error = do_statfs_native(&st, buf);
198 return error; 178 return error;
199 } 179 }
200 180
201 SYSCALL_DEFINE3(statfs64, const char __user *, 181 SYSCALL_DEFINE3(statfs64, const char __user *, pathname, size_t, sz, struct statfs64 __user *, buf)
202 { 182 {
203 struct kstatfs st; 183 struct kstatfs st;
204 int error; 184 int error;
205 if (sz != sizeof(*buf)) 185 if (sz != sizeof(*buf))
206 return -EINVAL; 186 return -EINVAL;
207 error = user_statfs(pathname, &st); 187 error = user_statfs(pathname, &st);
208 if (!error) 188 if (!error)
209 error = do_statfs64(&st, buf); 189 error = do_statfs64(&st, buf);
210 return error; 190 return error;
211 } 191 }
212 192
213 SYSCALL_DEFINE2(fstatfs, unsigned int, fd, str 193 SYSCALL_DEFINE2(fstatfs, unsigned int, fd, struct statfs __user *, buf)
214 { 194 {
215 struct kstatfs st; 195 struct kstatfs st;
216 int error = fd_statfs(fd, &st); 196 int error = fd_statfs(fd, &st);
217 if (!error) 197 if (!error)
218 error = do_statfs_native(&st, 198 error = do_statfs_native(&st, buf);
219 return error; 199 return error;
220 } 200 }
221 201
222 SYSCALL_DEFINE3(fstatfs64, unsigned int, fd, s 202 SYSCALL_DEFINE3(fstatfs64, unsigned int, fd, size_t, sz, struct statfs64 __user *, buf)
223 { 203 {
224 struct kstatfs st; 204 struct kstatfs st;
225 int error; 205 int error;
226 206
227 if (sz != sizeof(*buf)) 207 if (sz != sizeof(*buf))
228 return -EINVAL; 208 return -EINVAL;
229 209
230 error = fd_statfs(fd, &st); 210 error = fd_statfs(fd, &st);
231 if (!error) 211 if (!error)
232 error = do_statfs64(&st, buf); 212 error = do_statfs64(&st, buf);
233 return error; 213 return error;
234 } 214 }
235 215
236 static int vfs_ustat(dev_t dev, struct kstatfs !! 216 int vfs_ustat(dev_t dev, struct kstatfs *sbuf)
237 { 217 {
238 struct super_block *s = user_get_super !! 218 struct super_block *s = user_get_super(dev);
239 int err; 219 int err;
240 if (!s) 220 if (!s)
241 return -EINVAL; 221 return -EINVAL;
242 222
243 err = statfs_by_dentry(s->s_root, sbuf 223 err = statfs_by_dentry(s->s_root, sbuf);
244 drop_super(s); 224 drop_super(s);
245 return err; 225 return err;
246 } 226 }
247 227
248 SYSCALL_DEFINE2(ustat, unsigned, dev, struct u 228 SYSCALL_DEFINE2(ustat, unsigned, dev, struct ustat __user *, ubuf)
249 { 229 {
250 struct ustat tmp; 230 struct ustat tmp;
251 struct kstatfs sbuf; 231 struct kstatfs sbuf;
252 int err = vfs_ustat(new_decode_dev(dev 232 int err = vfs_ustat(new_decode_dev(dev), &sbuf);
253 if (err) 233 if (err)
254 return err; 234 return err;
255 235
256 memset(&tmp,0,sizeof(struct ustat)); 236 memset(&tmp,0,sizeof(struct ustat));
257 tmp.f_tfree = sbuf.f_bfree; 237 tmp.f_tfree = sbuf.f_bfree;
258 if (IS_ENABLED(CONFIG_ARCH_32BIT_USTAT !! 238 tmp.f_tinode = sbuf.f_ffree;
259 tmp.f_tinode = min_t(u64, sbuf <<
260 else <<
261 tmp.f_tinode = sbuf.f_ffree; <<
262 239
263 return copy_to_user(ubuf, &tmp, sizeof 240 return copy_to_user(ubuf, &tmp, sizeof(struct ustat)) ? -EFAULT : 0;
264 } 241 }
265 <<
266 #ifdef CONFIG_COMPAT <<
267 static int put_compat_statfs(struct compat_sta <<
268 { <<
269 struct compat_statfs buf; <<
270 if (sizeof ubuf->f_blocks == 4) { <<
271 if ((kbuf->f_blocks | kbuf->f_ <<
272 kbuf->f_bsize | kbuf->f_f <<
273 return -EOVERFLOW; <<
274 /* f_files and f_ffree may be <<
275 * to stuff that into 32 bits <<
276 if (kbuf->f_files != 0xfffffff <<
277 && (kbuf->f_files & 0xfffffff <<
278 return -EOVERFLOW; <<
279 if (kbuf->f_ffree != 0xfffffff <<
280 && (kbuf->f_ffree & 0xfffffff <<
281 return -EOVERFLOW; <<
282 } <<
283 memset(&buf, 0, sizeof(struct compat_s <<
284 buf.f_type = kbuf->f_type; <<
285 buf.f_bsize = kbuf->f_bsize; <<
286 buf.f_blocks = kbuf->f_blocks; <<
287 buf.f_bfree = kbuf->f_bfree; <<
288 buf.f_bavail = kbuf->f_bavail; <<
289 buf.f_files = kbuf->f_files; <<
290 buf.f_ffree = kbuf->f_ffree; <<
291 buf.f_namelen = kbuf->f_namelen; <<
292 buf.f_fsid.val[0] = kbuf->f_fsid.val[0 <<
293 buf.f_fsid.val[1] = kbuf->f_fsid.val[1 <<
294 buf.f_frsize = kbuf->f_frsize; <<
295 buf.f_flags = kbuf->f_flags; <<
296 if (copy_to_user(ubuf, &buf, sizeof(st <<
297 return -EFAULT; <<
298 return 0; <<
299 } <<
300 <<
301 /* <<
302 * The following statfs calls are copies of co <<
303 * should be checked against those from time t <<
304 */ <<
305 COMPAT_SYSCALL_DEFINE2(statfs, const char __us <<
306 { <<
307 struct kstatfs tmp; <<
308 int error = user_statfs(pathname, &tmp <<
309 if (!error) <<
310 error = put_compat_statfs(buf, <<
311 return error; <<
312 } <<
313 <<
314 COMPAT_SYSCALL_DEFINE2(fstatfs, unsigned int, <<
315 { <<
316 struct kstatfs tmp; <<
317 int error = fd_statfs(fd, &tmp); <<
318 if (!error) <<
319 error = put_compat_statfs(buf, <<
320 return error; <<
321 } <<
322 <<
323 static int put_compat_statfs64(struct compat_s <<
324 { <<
325 struct compat_statfs64 buf; <<
326 <<
327 if ((kbuf->f_bsize | kbuf->f_frsize) & <<
328 return -EOVERFLOW; <<
329 <<
330 memset(&buf, 0, sizeof(struct compat_s <<
331 buf.f_type = kbuf->f_type; <<
332 buf.f_bsize = kbuf->f_bsize; <<
333 buf.f_blocks = kbuf->f_blocks; <<
334 buf.f_bfree = kbuf->f_bfree; <<
335 buf.f_bavail = kbuf->f_bavail; <<
336 buf.f_files = kbuf->f_files; <<
337 buf.f_ffree = kbuf->f_ffree; <<
338 buf.f_namelen = kbuf->f_namelen; <<
339 buf.f_fsid.val[0] = kbuf->f_fsid.val[0 <<
340 buf.f_fsid.val[1] = kbuf->f_fsid.val[1 <<
341 buf.f_frsize = kbuf->f_frsize; <<
342 buf.f_flags = kbuf->f_flags; <<
343 if (copy_to_user(ubuf, &buf, sizeof(st <<
344 return -EFAULT; <<
345 return 0; <<
346 } <<
347 <<
348 int kcompat_sys_statfs64(const char __user * p <<
349 { <<
350 struct kstatfs tmp; <<
351 int error; <<
352 <<
353 if (sz != sizeof(*buf)) <<
354 return -EINVAL; <<
355 <<
356 error = user_statfs(pathname, &tmp); <<
357 if (!error) <<
358 error = put_compat_statfs64(bu <<
359 return error; <<
360 } <<
361 <<
362 COMPAT_SYSCALL_DEFINE3(statfs64, const char __ <<
363 { <<
364 return kcompat_sys_statfs64(pathname, <<
365 } <<
366 <<
367 int kcompat_sys_fstatfs64(unsigned int fd, com <<
368 { <<
369 struct kstatfs tmp; <<
370 int error; <<
371 <<
372 if (sz != sizeof(*buf)) <<
373 return -EINVAL; <<
374 <<
375 error = fd_statfs(fd, &tmp); <<
376 if (!error) <<
377 error = put_compat_statfs64(bu <<
378 return error; <<
379 } <<
380 <<
381 COMPAT_SYSCALL_DEFINE3(fstatfs64, unsigned int <<
382 { <<
383 return kcompat_sys_fstatfs64(fd, sz, b <<
384 } <<
385 <<
386 /* <<
387 * This is a copy of sys_ustat, just dealing w <<
388 * Given how simple this syscall is that appor <<
389 * than the various conversion hacks. <<
390 */ <<
391 COMPAT_SYSCALL_DEFINE2(ustat, unsigned, dev, s <<
392 { <<
393 struct compat_ustat tmp; <<
394 struct kstatfs sbuf; <<
395 int err = vfs_ustat(new_decode_dev(dev <<
396 if (err) <<
397 return err; <<
398 <<
399 memset(&tmp, 0, sizeof(struct compat_u <<
400 tmp.f_tfree = sbuf.f_bfree; <<
401 tmp.f_tinode = sbuf.f_ffree; <<
402 if (copy_to_user(u, &tmp, sizeof(struc <<
403 return -EFAULT; <<
404 return 0; <<
405 } <<
406 #endif <<
407 242
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