| 1 | |
| 2 | |
| 3 | * sysctl.c: General linux system control interface
|
| 4 |
|
| 5 |
|
| 6 | #include <linux/sysctl.h>
|
| 7 | #include <linux/bitmap.h>
|
| 8 | #include <linux/proc_fs.h>
|
| 9 | #include <linux/ctype.h>
|
| 10 | #include <linux/init.h>
|
| 11 | #include <linux/kernel.h>
|
| 12 | #include <linux/kobject.h>
|
| 13 | #include <linux/highuid.h>
|
| 14 | #include <linux/writeback.h>
|
| 15 | #include <linux/initrd.h>
|
| 16 | #include <linux/times.h>
|
| 17 | #include <linux/limits.h>
|
| 18 | #include <linux/syscalls.h>
|
| 19 | #include <linux/capability.h>
|
| 20 |
|
| 21 | #include "../lib/kstrtox.h"
|
| 22 |
|
| 23 | #include <linux/uaccess.h>
|
| 24 | #include <asm/processor.h>
|
| 25 |
|
| 26 |
|
| 27 | const int sysctl_vals[] = { 0, 1, 2, 3, 4, 100, 200, 1000, 3000, INT_MAX, 65535, -1 };
|
| 28 | EXPORT_SYMBOL(sysctl_vals);
|
| 29 |
|
| 30 | const unsigned long sysctl_long_vals[] = { 0, 1, LONG_MAX };
|
| 31 | EXPORT_SYMBOL_GPL(sysctl_long_vals);
|
| 32 |
|
| 33 | #if defined(CONFIG_SYSCTL)
|
| 34 |
|
| 35 |
|
| 36 | static const int ngroups_max = NGROUPS_MAX;
|
| 37 | static const int cap_last_cap = CAP_LAST_CAP;
|
| 38 |
|
| 39 | #ifdef CONFIG_PROC_SYSCTL
|
| 40 |
|
| 41 | |
| 42 | * enum sysctl_writes_mode - supported sysctl write modes
|
| 43 | *
|
| 44 | * @SYSCTL_WRITES_LEGACY: each write syscall must fully contain the sysctl value
|
| 45 | * to be written, and multiple writes on the same sysctl file descriptor
|
| 46 | * will rewrite the sysctl value, regardless of file position. No warning
|
| 47 | * is issued when the initial position is not 0.
|
| 48 | * @SYSCTL_WRITES_WARN: same as above but warn when the initial file position is
|
| 49 | * not 0.
|
| 50 | * @SYSCTL_WRITES_STRICT: writes to numeric sysctl entries must always be at
|
| 51 | * file position 0 and the value must be fully contained in the buffer
|
| 52 | * sent to the write syscall. If dealing with strings respect the file
|
| 53 | * position, but restrict this to the max length of the buffer, anything
|
| 54 | * passed the max length will be ignored. Multiple writes will append
|
| 55 | * to the buffer.
|
| 56 | *
|
| 57 | * These write modes control how current file position affects the behavior of
|
| 58 | * updating sysctl values through the proc interface on each write.
|
| 59 |
|
| 60 | enum sysctl_writes_mode {
|
| 61 | SYSCTL_WRITES_LEGACY = -1,
|
| 62 | SYSCTL_WRITES_WARN = 0,
|
| 63 | SYSCTL_WRITES_STRICT = 1,
|
| 64 | };
|
| 65 |
|
| 66 | static enum sysctl_writes_mode sysctl_writes_strict = SYSCTL_WRITES_STRICT;
|
| 67 | #endif
|
| 68 | #endif
|
| 69 |
|
| 70 | |
| 71 | * /proc/sys support
|
| 72 |
|
| 73 |
|
| 74 | #ifdef CONFIG_PROC_SYSCTL
|
| 75 |
|
| 76 | static int _proc_do_string(char *data, int maxlen, int write,
|
| 77 | char *buffer, size_t *lenp, loff_t *ppos)
|
| 78 | {
|
| 79 | size_t len;
|
| 80 | char c, *p;
|
| 81 |
|
| 82 | if (!data || !maxlen || !*lenp) {
|
| 83 | *lenp = 0;
|
| 84 | return 0;
|
| 85 | }
|
| 86 |
|
| 87 | if (write) {
|
| 88 | if (sysctl_writes_strict == SYSCTL_WRITES_STRICT) {
|
| 89 |
|
| 90 | len = strlen(data);
|
| 91 | if (len > maxlen - 1)
|
| 92 | len = maxlen - 1;
|
| 93 |
|
| 94 | if (*ppos > len)
|
| 95 | return 0;
|
| 96 | len = *ppos;
|
| 97 | } else {
|
| 98 |
|
| 99 | len = 0;
|
| 100 | }
|
| 101 |
|
| 102 | *ppos += *lenp;
|
| 103 | p = buffer;
|
| 104 | while ((p - buffer) < *lenp && len < maxlen - 1) {
|
| 105 | c = *(p++);
|
| 106 | if (c == 0 || c == '\n')
|
| 107 | break;
|
| 108 | data[len++] = c;
|
| 109 | }
|
| 110 | data[len] = 0;
|
| 111 | } else {
|
| 112 | len = strlen(data);
|
| 113 | if (len > maxlen)
|
| 114 | len = maxlen;
|
| 115 |
|
| 116 | if (*ppos > len) {
|
| 117 | *lenp = 0;
|
| 118 | return 0;
|
| 119 | }
|
| 120 |
|
| 121 | data += *ppos;
|
| 122 | len -= *ppos;
|
| 123 |
|
| 124 | if (len > *lenp)
|
| 125 | len = *lenp;
|
| 126 | if (len)
|
| 127 | memcpy(buffer, data, len);
|
| 128 | if (len < *lenp) {
|
| 129 | buffer[len] = '\n';
|
| 130 | len++;
|
| 131 | }
|
| 132 | *lenp = len;
|
| 133 | *ppos += len;
|
| 134 | }
|
| 135 | return 0;
|
| 136 | }
|
| 137 |
|
| 138 | static void warn_sysctl_write(const struct ctl_table *table)
|
| 139 | {
|
| 140 | pr_warn_once("%s wrote to %s when file position was not 0!\n"
|
| 141 | "This will not be supported in the future. To silence this\n"
|
| 142 | "warning, set kernel.sysctl_writes_strict = -1\n",
|
| 143 | current->comm, table->procname);
|
| 144 | }
|
| 145 |
|
| 146 | |
| 147 | * proc_first_pos_non_zero_ignore - check if first position is allowed
|
| 148 | * @ppos: file position
|
| 149 | * @table: the sysctl table
|
| 150 | *
|
| 151 | * Returns true if the first position is non-zero and the sysctl_writes_strict
|
| 152 | * mode indicates this is not allowed for numeric input types. String proc
|
| 153 | * handlers can ignore the return value.
|
| 154 |
|
| 155 | static bool proc_first_pos_non_zero_ignore(loff_t *ppos,
|
| 156 | const struct ctl_table *table)
|
| 157 | {
|
| 158 | if (!*ppos)
|
| 159 | return false;
|
| 160 |
|
| 161 | switch (sysctl_writes_strict) {
|
| 162 | case SYSCTL_WRITES_STRICT:
|
| 163 | return true;
|
| 164 | case SYSCTL_WRITES_WARN:
|
| 165 | warn_sysctl_write(table);
|
| 166 | return false;
|
| 167 | default:
|
| 168 | return false;
|
| 169 | }
|
| 170 | }
|
| 171 |
|
| 172 | |
| 173 | * proc_dostring - read a string sysctl
|
| 174 | * @table: the sysctl table
|
| 175 | * @write: %TRUE if this is a write to the sysctl file
|
| 176 | * @buffer: the user buffer
|
| 177 | * @lenp: the size of the user buffer
|
| 178 | * @ppos: file position
|
| 179 | *
|
| 180 | * Reads/writes a string from/to the user buffer. If the kernel
|
| 181 | * buffer provided is not large enough to hold the string, the
|
| 182 | * string is truncated. The copied string is %NULL-terminated.
|
| 183 | * If the string is being read by the user process, it is copied
|
| 184 | * and a newline '\n' is added. It is truncated if the buffer is
|
| 185 | * not large enough.
|
| 186 | *
|
| 187 | * Returns 0 on success.
|
| 188 |
|
| 189 | int proc_dostring(const struct ctl_table *table, int write,
|
| 190 | void *buffer, size_t *lenp, loff_t *ppos)
|
| 191 | {
|
| 192 | if (write)
|
| 193 | proc_first_pos_non_zero_ignore(ppos, table);
|
| 194 |
|
| 195 | return _proc_do_string(table->data, table->maxlen, write, buffer, lenp,
|
| 196 | ppos);
|
| 197 | }
|
| 198 |
|
| 199 | static void proc_skip_spaces(char **buf, size_t *size)
|
| 200 | {
|
| 201 | while (*size) {
|
| 202 | if (!isspace(**buf))
|
| 203 | break;
|
| 204 | (*size)--;
|
| 205 | (*buf)++;
|
| 206 | }
|
| 207 | }
|
| 208 |
|
| 209 | static void proc_skip_char(char **buf, size_t *size, const char v)
|
| 210 | {
|
| 211 | while (*size) {
|
| 212 | if (**buf != v)
|
| 213 | break;
|
| 214 | (*size)--;
|
| 215 | (*buf)++;
|
| 216 | }
|
| 217 | }
|
| 218 |
|
| 219 | |
| 220 | * strtoul_lenient - parse an ASCII formatted integer from a buffer and only
|
| 221 | * fail on overflow
|
| 222 | *
|
| 223 | * @cp: kernel buffer containing the string to parse
|
| 224 | * @endp: pointer to store the trailing characters
|
| 225 | * @base: the base to use
|
| 226 | * @res: where the parsed integer will be stored
|
| 227 | *
|
| 228 | * In case of success 0 is returned and @res will contain the parsed integer,
|
| 229 | * @endp will hold any trailing characters.
|
| 230 | * This function will fail the parse on overflow. If there wasn't an overflow
|
| 231 | * the function will defer the decision what characters count as invalid to the
|
| 232 | * caller.
|
| 233 |
|
| 234 | static int strtoul_lenient(const char *cp, char **endp, unsigned int base,
|
| 235 | unsigned long *res)
|
| 236 | {
|
| 237 | unsigned long long result;
|
| 238 | unsigned int rv;
|
| 239 |
|
| 240 | cp = _parse_integer_fixup_radix(cp, &base);
|
| 241 | rv = _parse_integer(cp, base, &result);
|
| 242 | if ((rv & KSTRTOX_OVERFLOW) || (result != (unsigned long)result))
|
| 243 | return -ERANGE;
|
| 244 |
|
| 245 | cp += rv;
|
| 246 |
|
| 247 | if (endp)
|
| 248 | *endp = (char *)cp;
|
| 249 |
|
| 250 | *res = (unsigned long)result;
|
| 251 | return 0;
|
| 252 | }
|
| 253 |
|
| 254 | #define TMPBUFLEN 22
|
| 255 | |
| 256 | * proc_get_long - reads an ASCII formatted integer from a user buffer
|
| 257 | *
|
| 258 | * @buf: a kernel buffer
|
| 259 | * @size: size of the kernel buffer
|
| 260 | * @val: this is where the number will be stored
|
| 261 | * @neg: set to %TRUE if number is negative
|
| 262 | * @perm_tr: a vector which contains the allowed trailers
|
| 263 | * @perm_tr_len: size of the perm_tr vector
|
| 264 | * @tr: pointer to store the trailer character
|
| 265 | *
|
| 266 | * In case of success %0 is returned and @buf and @size are updated with
|
| 267 | * the amount of bytes read. If @tr is non-NULL and a trailing
|
| 268 | * character exists (size is non-zero after returning from this
|
| 269 | * function), @tr is updated with the trailing character.
|
| 270 |
|
| 271 | static int proc_get_long(char **buf, size_t *size,
|
| 272 | unsigned long *val, bool *neg,
|
| 273 | const char *perm_tr, unsigned perm_tr_len, char *tr)
|
| 274 | {
|
| 275 | char *p, tmp[TMPBUFLEN];
|
| 276 | ssize_t len = *size;
|
| 277 |
|
| 278 | if (len <= 0)
|
| 279 | return -EINVAL;
|
| 280 |
|
| 281 | if (len > TMPBUFLEN - 1)
|
| 282 | len = TMPBUFLEN - 1;
|
| 283 |
|
| 284 | memcpy(tmp, *buf, len);
|
| 285 |
|
| 286 | tmp[len] = 0;
|
| 287 | p = tmp;
|
| 288 | if (*p == '-' && *size > 1) {
|
| 289 | *neg = true;
|
| 290 | p++;
|
| 291 | } else
|
| 292 | *neg = false;
|
| 293 | if (!isdigit(*p))
|
| 294 | return -EINVAL;
|
| 295 |
|
| 296 | if (strtoul_lenient(p, &p, 0, val))
|
| 297 | return -EINVAL;
|
| 298 |
|
| 299 | len = p - tmp;
|
| 300 |
|
| 301 | |
| 302 | * invalid integers (e.g. 1234...a) or two integers instead of one
|
| 303 | * (e.g. 123...1). So lets not allow such large numbers.
|
| 304 | if (len == TMPBUFLEN - 1)
|
| 305 | return -EINVAL;
|
| 306 |
|
| 307 | if (len < *size && perm_tr_len && !memchr(perm_tr, *p, perm_tr_len))
|
| 308 | return -EINVAL;
|
| 309 |
|
| 310 | if (tr && (len < *size))
|
| 311 | *tr = *p;
|
| 312 |
|
| 313 | *buf += len;
|
| 314 | *size -= len;
|
| 315 |
|
| 316 | return 0;
|
| 317 | }
|
| 318 |
|
| 319 | |
| 320 | * proc_put_long - converts an integer to a decimal ASCII formatted string
|
| 321 | *
|
| 322 | * @buf: the user buffer
|
| 323 | * @size: the size of the user buffer
|
| 324 | * @val: the integer to be converted
|
| 325 | * @neg: sign of the number, %TRUE for negative
|
| 326 | *
|
| 327 | * In case of success @buf and @size are updated with the amount of bytes
|
| 328 | * written.
|
| 329 |
|
| 330 | static void proc_put_long(void **buf, size_t *size, unsigned long val, bool neg)
|
| 331 | {
|
| 332 | int len;
|
| 333 | char tmp[TMPBUFLEN], *p = tmp;
|
| 334 |
|
| 335 | sprintf(p, "%s%lu", neg ? "-" : "", val);
|
| 336 | len = strlen(tmp);
|
| 337 | if (len > *size)
|
| 338 | len = *size;
|
| 339 | memcpy(*buf, tmp, len);
|
| 340 | *size -= len;
|
| 341 | *buf += len;
|
| 342 | }
|
| 343 | #undef TMPBUFLEN
|
| 344 |
|
| 345 | static void proc_put_char(void **buf, size_t *size, char c)
|
| 346 | {
|
| 347 | if (*size) {
|
| 348 | char **buffer = (char **)buf;
|
| 349 | **buffer = c;
|
| 350 |
|
| 351 | (*size)--;
|
| 352 | (*buffer)++;
|
| 353 | *buf = *buffer;
|
| 354 | }
|
| 355 | }
|
| 356 |
|
| 357 | static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp,
|
| 358 | int *valp,
|
| 359 | int write, void *data)
|
| 360 | {
|
| 361 | if (write) {
|
| 362 | if (*negp) {
|
| 363 | if (*lvalp > (unsigned long) INT_MAX + 1)
|
| 364 | return -EINVAL;
|
| 365 | WRITE_ONCE(*valp, -*lvalp);
|
| 366 | } else {
|
| 367 | if (*lvalp > (unsigned long) INT_MAX)
|
| 368 | return -EINVAL;
|
| 369 | WRITE_ONCE(*valp, *lvalp);
|
| 370 | }
|
| 371 | } else {
|
| 372 | int val = READ_ONCE(*valp);
|
| 373 | if (val < 0) {
|
| 374 | *negp = true;
|
| 375 | *lvalp = -(unsigned long)val;
|
| 376 | } else {
|
| 377 | *negp = false;
|
| 378 | *lvalp = (unsigned long)val;
|
| 379 | }
|
| 380 | }
|
| 381 | return 0;
|
| 382 | }
|
| 383 |
|
| 384 | static int do_proc_douintvec_conv(unsigned long *lvalp,
|
| 385 | unsigned int *valp,
|
| 386 | int write, void *data)
|
| 387 | {
|
| 388 | if (write) {
|
| 389 | if (*lvalp > UINT_MAX)
|
| 390 | return -EINVAL;
|
| 391 | WRITE_ONCE(*valp, *lvalp);
|
| 392 | } else {
|
| 393 | unsigned int val = READ_ONCE(*valp);
|
| 394 | *lvalp = (unsigned long)val;
|
| 395 | }
|
| 396 | return 0;
|
| 397 | }
|
| 398 |
|
| 399 | static const char proc_wspace_sep[] = { ' ', '\t', '\n' };
|
| 400 |
|
| 401 | static int __do_proc_dointvec(void *tbl_data, const struct ctl_table *table,
|
| 402 | int write, void *buffer,
|
| 403 | size_t *lenp, loff_t *ppos,
|
| 404 | int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
|
| 405 | int write, void *data),
|
| 406 | void *data)
|
| 407 | {
|
| 408 | int *i, vleft, first = 1, err = 0;
|
| 409 | size_t left;
|
| 410 | char *p;
|
| 411 |
|
| 412 | if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
|
| 413 | *lenp = 0;
|
| 414 | return 0;
|
| 415 | }
|
| 416 |
|
| 417 | i = (int *) tbl_data;
|
| 418 | vleft = table->maxlen / sizeof(*i);
|
| 419 | left = *lenp;
|
| 420 |
|
| 421 | if (!conv)
|
| 422 | conv = do_proc_dointvec_conv;
|
| 423 |
|
| 424 | if (write) {
|
| 425 | if (proc_first_pos_non_zero_ignore(ppos, table))
|
| 426 | goto out;
|
| 427 |
|
| 428 | if (left > PAGE_SIZE - 1)
|
| 429 | left = PAGE_SIZE - 1;
|
| 430 | p = buffer;
|
| 431 | }
|
| 432 |
|
| 433 | for (; left && vleft--; i++, first=0) {
|
| 434 | unsigned long lval;
|
| 435 | bool neg;
|
| 436 |
|
| 437 | if (write) {
|
| 438 | proc_skip_spaces(&p, &left);
|
| 439 |
|
| 440 | if (!left)
|
| 441 | break;
|
| 442 | err = proc_get_long(&p, &left, &lval, &neg,
|
| 443 | proc_wspace_sep,
|
| 444 | sizeof(proc_wspace_sep), NULL);
|
| 445 | if (err)
|
| 446 | break;
|
| 447 | if (conv(&neg, &lval, i, 1, data)) {
|
| 448 | err = -EINVAL;
|
| 449 | break;
|
| 450 | }
|
| 451 | } else {
|
| 452 | if (conv(&neg, &lval, i, 0, data)) {
|
| 453 | err = -EINVAL;
|
| 454 | break;
|
| 455 | }
|
| 456 | if (!first)
|
| 457 | proc_put_char(&buffer, &left, '\t');
|
| 458 | proc_put_long(&buffer, &left, lval, neg);
|
| 459 | }
|
| 460 | }
|
| 461 |
|
| 462 | if (!write && !first && left && !err)
|
| 463 | proc_put_char(&buffer, &left, '\n');
|
| 464 | if (write && !err && left)
|
| 465 | proc_skip_spaces(&p, &left);
|
| 466 | if (write && first)
|
| 467 | return err ? : -EINVAL;
|
| 468 | *lenp -= left;
|
| 469 | out:
|
| 470 | *ppos += *lenp;
|
| 471 | return err;
|
| 472 | }
|
| 473 |
|
| 474 | static int do_proc_dointvec(const struct ctl_table *table, int write,
|
| 475 | void *buffer, size_t *lenp, loff_t *ppos,
|
| 476 | int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
|
| 477 | int write, void *data),
|
| 478 | void *data)
|
| 479 | {
|
| 480 | return __do_proc_dointvec(table->data, table, write,
|
| 481 | buffer, lenp, ppos, conv, data);
|
| 482 | }
|
| 483 |
|
| 484 | static int do_proc_douintvec_w(unsigned int *tbl_data,
|
| 485 | const struct ctl_table *table,
|
| 486 | void *buffer,
|
| 487 | size_t *lenp, loff_t *ppos,
|
| 488 | int (*conv)(unsigned long *lvalp,
|
| 489 | unsigned int *valp,
|
| 490 | int write, void *data),
|
| 491 | void *data)
|
| 492 | {
|
| 493 | unsigned long lval;
|
| 494 | int err = 0;
|
| 495 | size_t left;
|
| 496 | bool neg;
|
| 497 | char *p = buffer;
|
| 498 |
|
| 499 | left = *lenp;
|
| 500 |
|
| 501 | if (proc_first_pos_non_zero_ignore(ppos, table))
|
| 502 | goto bail_early;
|
| 503 |
|
| 504 | if (left > PAGE_SIZE - 1)
|
| 505 | left = PAGE_SIZE - 1;
|
| 506 |
|
| 507 | proc_skip_spaces(&p, &left);
|
| 508 | if (!left) {
|
| 509 | err = -EINVAL;
|
| 510 | goto out_free;
|
| 511 | }
|
| 512 |
|
| 513 | err = proc_get_long(&p, &left, &lval, &neg,
|
| 514 | proc_wspace_sep,
|
| 515 | sizeof(proc_wspace_sep), NULL);
|
| 516 | if (err || neg) {
|
| 517 | err = -EINVAL;
|
| 518 | goto out_free;
|
| 519 | }
|
| 520 |
|
| 521 | if (conv(&lval, tbl_data, 1, data)) {
|
| 522 | err = -EINVAL;
|
| 523 | goto out_free;
|
| 524 | }
|
| 525 |
|
| 526 | if (!err && left)
|
| 527 | proc_skip_spaces(&p, &left);
|
| 528 |
|
| 529 | out_free:
|
| 530 | if (err)
|
| 531 | return -EINVAL;
|
| 532 |
|
| 533 | return 0;
|
| 534 |
|
| 535 |
|
| 536 | bail_early:
|
| 537 | *ppos += *lenp;
|
| 538 | return err;
|
| 539 | }
|
| 540 |
|
| 541 | static int do_proc_douintvec_r(unsigned int *tbl_data, void *buffer,
|
| 542 | size_t *lenp, loff_t *ppos,
|
| 543 | int (*conv)(unsigned long *lvalp,
|
| 544 | unsigned int *valp,
|
| 545 | int write, void *data),
|
| 546 | void *data)
|
| 547 | {
|
| 548 | unsigned long lval;
|
| 549 | int err = 0;
|
| 550 | size_t left;
|
| 551 |
|
| 552 | left = *lenp;
|
| 553 |
|
| 554 | if (conv(&lval, tbl_data, 0, data)) {
|
| 555 | err = -EINVAL;
|
| 556 | goto out;
|
| 557 | }
|
| 558 |
|
| 559 | proc_put_long(&buffer, &left, lval, false);
|
| 560 | if (!left)
|
| 561 | goto out;
|
| 562 |
|
| 563 | proc_put_char(&buffer, &left, '\n');
|
| 564 |
|
| 565 | out:
|
| 566 | *lenp -= left;
|
| 567 | *ppos += *lenp;
|
| 568 |
|
| 569 | return err;
|
| 570 | }
|
| 571 |
|
| 572 | static int __do_proc_douintvec(void *tbl_data, const struct ctl_table *table,
|
| 573 | int write, void *buffer,
|
| 574 | size_t *lenp, loff_t *ppos,
|
| 575 | int (*conv)(unsigned long *lvalp,
|
| 576 | unsigned int *valp,
|
| 577 | int write, void *data),
|
| 578 | void *data)
|
| 579 | {
|
| 580 | unsigned int *i, vleft;
|
| 581 |
|
| 582 | if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
|
| 583 | *lenp = 0;
|
| 584 | return 0;
|
| 585 | }
|
| 586 |
|
| 587 | i = (unsigned int *) tbl_data;
|
| 588 | vleft = table->maxlen / sizeof(*i);
|
| 589 |
|
| 590 | |
| 591 | * Arrays are not supported, keep this simple. *Do not* add
|
| 592 | * support for them.
|
| 593 |
|
| 594 | if (vleft != 1) {
|
| 595 | *lenp = 0;
|
| 596 | return -EINVAL;
|
| 597 | }
|
| 598 |
|
| 599 | if (!conv)
|
| 600 | conv = do_proc_douintvec_conv;
|
| 601 |
|
| 602 | if (write)
|
| 603 | return do_proc_douintvec_w(i, table, buffer, lenp, ppos,
|
| 604 | conv, data);
|
| 605 | return do_proc_douintvec_r(i, buffer, lenp, ppos, conv, data);
|
| 606 | }
|
| 607 |
|
| 608 | int do_proc_douintvec(const struct ctl_table *table, int write,
|
| 609 | void *buffer, size_t *lenp, loff_t *ppos,
|
| 610 | int (*conv)(unsigned long *lvalp,
|
| 611 | unsigned int *valp,
|
| 612 | int write, void *data),
|
| 613 | void *data)
|
| 614 | {
|
| 615 | return __do_proc_douintvec(table->data, table, write,
|
| 616 | buffer, lenp, ppos, conv, data);
|
| 617 | }
|
| 618 |
|
| 619 | |
| 620 | * proc_dobool - read/write a bool
|
| 621 | * @table: the sysctl table
|
| 622 | * @write: %TRUE if this is a write to the sysctl file
|
| 623 | * @buffer: the user buffer
|
| 624 | * @lenp: the size of the user buffer
|
| 625 | * @ppos: file position
|
| 626 | *
|
| 627 | * Reads/writes one integer value from/to the user buffer,
|
| 628 | * treated as an ASCII string.
|
| 629 | *
|
| 630 | * table->data must point to a bool variable and table->maxlen must
|
| 631 | * be sizeof(bool).
|
| 632 | *
|
| 633 | * Returns 0 on success.
|
| 634 |
|
| 635 | int proc_dobool(const struct ctl_table *table, int write, void *buffer,
|
| 636 | size_t *lenp, loff_t *ppos)
|
| 637 | {
|
| 638 | struct ctl_table tmp;
|
| 639 | bool *data = table->data;
|
| 640 | int res, val;
|
| 641 |
|
| 642 |
|
| 643 | if (table->maxlen != sizeof(bool))
|
| 644 | return -EINVAL;
|
| 645 |
|
| 646 | tmp = *table;
|
| 647 | tmp.maxlen = sizeof(val);
|
| 648 | tmp.data = &val;
|
| 649 |
|
| 650 | val = READ_ONCE(*data);
|
| 651 | res = proc_dointvec(&tmp, write, buffer, lenp, ppos);
|
| 652 | if (res)
|
| 653 | return res;
|
| 654 | if (write)
|
| 655 | WRITE_ONCE(*data, val);
|
| 656 | return 0;
|
| 657 | }
|
| 658 |
|
| 659 | |
| 660 | * proc_dointvec - read a vector of integers
|
| 661 | * @table: the sysctl table
|
| 662 | * @write: %TRUE if this is a write to the sysctl file
|
| 663 | * @buffer: the user buffer
|
| 664 | * @lenp: the size of the user buffer
|
| 665 | * @ppos: file position
|
| 666 | *
|
| 667 | * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
|
| 668 | * values from/to the user buffer, treated as an ASCII string.
|
| 669 | *
|
| 670 | * Returns 0 on success.
|
| 671 |
|
| 672 | int proc_dointvec(const struct ctl_table *table, int write, void *buffer,
|
| 673 | size_t *lenp, loff_t *ppos)
|
| 674 | {
|
| 675 | return do_proc_dointvec(table, write, buffer, lenp, ppos, NULL, NULL);
|
| 676 | }
|
| 677 |
|
| 678 | |
| 679 | * proc_douintvec - read a vector of unsigned integers
|
| 680 | * @table: the sysctl table
|
| 681 | * @write: %TRUE if this is a write to the sysctl file
|
| 682 | * @buffer: the user buffer
|
| 683 | * @lenp: the size of the user buffer
|
| 684 | * @ppos: file position
|
| 685 | *
|
| 686 | * Reads/writes up to table->maxlen/sizeof(unsigned int) unsigned integer
|
| 687 | * values from/to the user buffer, treated as an ASCII string.
|
| 688 | *
|
| 689 | * Returns 0 on success.
|
| 690 |
|
| 691 | int proc_douintvec(const struct ctl_table *table, int write, void *buffer,
|
| 692 | size_t *lenp, loff_t *ppos)
|
| 693 | {
|
| 694 | return do_proc_douintvec(table, write, buffer, lenp, ppos,
|
| 695 | do_proc_douintvec_conv, NULL);
|
| 696 | }
|
| 697 |
|
| 698 | |
| 699 | * struct do_proc_dointvec_minmax_conv_param - proc_dointvec_minmax() range checking structure
|
| 700 | * @min: pointer to minimum allowable value
|
| 701 | * @max: pointer to maximum allowable value
|
| 702 | *
|
| 703 | * The do_proc_dointvec_minmax_conv_param structure provides the
|
| 704 | * minimum and maximum values for doing range checking for those sysctl
|
| 705 | * parameters that use the proc_dointvec_minmax() handler.
|
| 706 |
|
| 707 | struct do_proc_dointvec_minmax_conv_param {
|
| 708 | int *min;
|
| 709 | int *max;
|
| 710 | };
|
| 711 |
|
| 712 | static int do_proc_dointvec_minmax_conv(bool *negp, unsigned long *lvalp,
|
| 713 | int *valp,
|
| 714 | int write, void *data)
|
| 715 | {
|
| 716 | int tmp, ret;
|
| 717 | struct do_proc_dointvec_minmax_conv_param *param = data;
|
| 718 | |
| 719 | * If writing, first do so via a temporary local int so we can
|
| 720 | * bounds-check it before touching *valp.
|
| 721 |
|
| 722 | int *ip = write ? &tmp : valp;
|
| 723 |
|
| 724 | ret = do_proc_dointvec_conv(negp, lvalp, ip, write, data);
|
| 725 | if (ret)
|
| 726 | return ret;
|
| 727 |
|
| 728 | if (write) {
|
| 729 | if ((param->min && *param->min > tmp) ||
|
| 730 | (param->max && *param->max < tmp))
|
| 731 | return -EINVAL;
|
| 732 | WRITE_ONCE(*valp, tmp);
|
| 733 | }
|
| 734 |
|
| 735 | return 0;
|
| 736 | }
|
| 737 |
|
| 738 | |
| 739 | * proc_dointvec_minmax - read a vector of integers with min/max values
|
| 740 | * @table: the sysctl table
|
| 741 | * @write: %TRUE if this is a write to the sysctl file
|
| 742 | * @buffer: the user buffer
|
| 743 | * @lenp: the size of the user buffer
|
| 744 | * @ppos: file position
|
| 745 | *
|
| 746 | * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
|
| 747 | * values from/to the user buffer, treated as an ASCII string.
|
| 748 | *
|
| 749 | * This routine will ensure the values are within the range specified by
|
| 750 | * table->extra1 (min) and table->extra2 (max).
|
| 751 | *
|
| 752 | * Returns 0 on success or -EINVAL on write when the range check fails.
|
| 753 |
|
| 754 | int proc_dointvec_minmax(const struct ctl_table *table, int write,
|
| 755 | void *buffer, size_t *lenp, loff_t *ppos)
|
| 756 | {
|
| 757 | struct do_proc_dointvec_minmax_conv_param param = {
|
| 758 | .min = (int *) table->extra1,
|
| 759 | .max = (int *) table->extra2,
|
| 760 | };
|
| 761 | return do_proc_dointvec(table, write, buffer, lenp, ppos,
|
| 762 | do_proc_dointvec_minmax_conv, ¶m);
|
| 763 | }
|
| 764 |
|
| 765 | |
| 766 | * struct do_proc_douintvec_minmax_conv_param - proc_douintvec_minmax() range checking structure
|
| 767 | * @min: pointer to minimum allowable value
|
| 768 | * @max: pointer to maximum allowable value
|
| 769 | *
|
| 770 | * The do_proc_douintvec_minmax_conv_param structure provides the
|
| 771 | * minimum and maximum values for doing range checking for those sysctl
|
| 772 | * parameters that use the proc_douintvec_minmax() handler.
|
| 773 |
|
| 774 | struct do_proc_douintvec_minmax_conv_param {
|
| 775 | unsigned int *min;
|
| 776 | unsigned int *max;
|
| 777 | };
|
| 778 |
|
| 779 | static int do_proc_douintvec_minmax_conv(unsigned long *lvalp,
|
| 780 | unsigned int *valp,
|
| 781 | int write, void *data)
|
| 782 | {
|
| 783 | int ret;
|
| 784 | unsigned int tmp;
|
| 785 | struct do_proc_douintvec_minmax_conv_param *param = data;
|
| 786 |
|
| 787 | unsigned int *up = write ? &tmp : valp;
|
| 788 |
|
| 789 | ret = do_proc_douintvec_conv(lvalp, up, write, data);
|
| 790 | if (ret)
|
| 791 | return ret;
|
| 792 |
|
| 793 | if (write) {
|
| 794 | if ((param->min && *param->min > tmp) ||
|
| 795 | (param->max && *param->max < tmp))
|
| 796 | return -ERANGE;
|
| 797 |
|
| 798 | WRITE_ONCE(*valp, tmp);
|
| 799 | }
|
| 800 |
|
| 801 | return 0;
|
| 802 | }
|
| 803 |
|
| 804 | |
| 805 | * proc_douintvec_minmax - read a vector of unsigned ints with min/max values
|
| 806 | * @table: the sysctl table
|
| 807 | * @write: %TRUE if this is a write to the sysctl file
|
| 808 | * @buffer: the user buffer
|
| 809 | * @lenp: the size of the user buffer
|
| 810 | * @ppos: file position
|
| 811 | *
|
| 812 | * Reads/writes up to table->maxlen/sizeof(unsigned int) unsigned integer
|
| 813 | * values from/to the user buffer, treated as an ASCII string. Negative
|
| 814 | * strings are not allowed.
|
| 815 | *
|
| 816 | * This routine will ensure the values are within the range specified by
|
| 817 | * table->extra1 (min) and table->extra2 (max). There is a final sanity
|
| 818 | * check for UINT_MAX to avoid having to support wrap around uses from
|
| 819 | * userspace.
|
| 820 | *
|
| 821 | * Returns 0 on success or -ERANGE on write when the range check fails.
|
| 822 |
|
| 823 | int proc_douintvec_minmax(const struct ctl_table *table, int write,
|
| 824 | void *buffer, size_t *lenp, loff_t *ppos)
|
| 825 | {
|
| 826 | struct do_proc_douintvec_minmax_conv_param param = {
|
| 827 | .min = (unsigned int *) table->extra1,
|
| 828 | .max = (unsigned int *) table->extra2,
|
| 829 | };
|
| 830 | return do_proc_douintvec(table, write, buffer, lenp, ppos,
|
| 831 | do_proc_douintvec_minmax_conv, ¶m);
|
| 832 | }
|
| 833 |
|
| 834 | |
| 835 | * proc_dou8vec_minmax - read a vector of unsigned chars with min/max values
|
| 836 | * @table: the sysctl table
|
| 837 | * @write: %TRUE if this is a write to the sysctl file
|
| 838 | * @buffer: the user buffer
|
| 839 | * @lenp: the size of the user buffer
|
| 840 | * @ppos: file position
|
| 841 | *
|
| 842 | * Reads/writes up to table->maxlen/sizeof(u8) unsigned chars
|
| 843 | * values from/to the user buffer, treated as an ASCII string. Negative
|
| 844 | * strings are not allowed.
|
| 845 | *
|
| 846 | * This routine will ensure the values are within the range specified by
|
| 847 | * table->extra1 (min) and table->extra2 (max).
|
| 848 | *
|
| 849 | * Returns 0 on success or an error on write when the range check fails.
|
| 850 |
|
| 851 | int proc_dou8vec_minmax(const struct ctl_table *table, int write,
|
| 852 | void *buffer, size_t *lenp, loff_t *ppos)
|
| 853 | {
|
| 854 | struct ctl_table tmp;
|
| 855 | unsigned int min = 0, max = 255U, val;
|
| 856 | u8 *data = table->data;
|
| 857 | struct do_proc_douintvec_minmax_conv_param param = {
|
| 858 | .min = &min,
|
| 859 | .max = &max,
|
| 860 | };
|
| 861 | int res;
|
| 862 |
|
| 863 |
|
| 864 | if (table->maxlen != sizeof(u8))
|
| 865 | return -EINVAL;
|
| 866 |
|
| 867 | if (table->extra1)
|
| 868 | min = *(unsigned int *) table->extra1;
|
| 869 | if (table->extra2)
|
| 870 | max = *(unsigned int *) table->extra2;
|
| 871 |
|
| 872 | tmp = *table;
|
| 873 |
|
| 874 | tmp.maxlen = sizeof(val);
|
| 875 | tmp.data = &val;
|
| 876 | val = READ_ONCE(*data);
|
| 877 | res = do_proc_douintvec(&tmp, write, buffer, lenp, ppos,
|
| 878 | do_proc_douintvec_minmax_conv, ¶m);
|
| 879 | if (res)
|
| 880 | return res;
|
| 881 | if (write)
|
| 882 | WRITE_ONCE(*data, val);
|
| 883 | return 0;
|
| 884 | }
|
| 885 | EXPORT_SYMBOL_GPL(proc_dou8vec_minmax);
|
| 886 |
|
| 887 | static int __do_proc_doulongvec_minmax(void *data,
|
| 888 | const struct ctl_table *table, int write,
|
| 889 | void *buffer, size_t *lenp, loff_t *ppos,
|
| 890 | unsigned long convmul, unsigned long convdiv)
|
| 891 | {
|
| 892 | unsigned long *i, *min, *max;
|
| 893 | int vleft, first = 1, err = 0;
|
| 894 | size_t left;
|
| 895 | char *p;
|
| 896 |
|
| 897 | if (!data || !table->maxlen || !*lenp || (*ppos && !write)) {
|
| 898 | *lenp = 0;
|
| 899 | return 0;
|
| 900 | }
|
| 901 |
|
| 902 | i = data;
|
| 903 | min = table->extra1;
|
| 904 | max = table->extra2;
|
| 905 | vleft = table->maxlen / sizeof(unsigned long);
|
| 906 | left = *lenp;
|
| 907 |
|
| 908 | if (write) {
|
| 909 | if (proc_first_pos_non_zero_ignore(ppos, table))
|
| 910 | goto out;
|
| 911 |
|
| 912 | if (left > PAGE_SIZE - 1)
|
| 913 | left = PAGE_SIZE - 1;
|
| 914 | p = buffer;
|
| 915 | }
|
| 916 |
|
| 917 | for (; left && vleft--; i++, first = 0) {
|
| 918 | unsigned long val;
|
| 919 |
|
| 920 | if (write) {
|
| 921 | bool neg;
|
| 922 |
|
| 923 | proc_skip_spaces(&p, &left);
|
| 924 | if (!left)
|
| 925 | break;
|
| 926 |
|
| 927 | err = proc_get_long(&p, &left, &val, &neg,
|
| 928 | proc_wspace_sep,
|
| 929 | sizeof(proc_wspace_sep), NULL);
|
| 930 | if (err || neg) {
|
| 931 | err = -EINVAL;
|
| 932 | break;
|
| 933 | }
|
| 934 |
|
| 935 | val = convmul * val / convdiv;
|
| 936 | if ((min && val < *min) || (max && val > *max)) {
|
| 937 | err = -EINVAL;
|
| 938 | break;
|
| 939 | }
|
| 940 | WRITE_ONCE(*i, val);
|
| 941 | } else {
|
| 942 | val = convdiv * READ_ONCE(*i) / convmul;
|
| 943 | if (!first)
|
| 944 | proc_put_char(&buffer, &left, '\t');
|
| 945 | proc_put_long(&buffer, &left, val, false);
|
| 946 | }
|
| 947 | }
|
| 948 |
|
| 949 | if (!write && !first && left && !err)
|
| 950 | proc_put_char(&buffer, &left, '\n');
|
| 951 | if (write && !err)
|
| 952 | proc_skip_spaces(&p, &left);
|
| 953 | if (write && first)
|
| 954 | return err ? : -EINVAL;
|
| 955 | *lenp -= left;
|
| 956 | out:
|
| 957 | *ppos += *lenp;
|
| 958 | return err;
|
| 959 | }
|
| 960 |
|
| 961 | static int do_proc_doulongvec_minmax(const struct ctl_table *table, int write,
|
| 962 | void *buffer, size_t *lenp, loff_t *ppos, unsigned long convmul,
|
| 963 | unsigned long convdiv)
|
| 964 | {
|
| 965 | return __do_proc_doulongvec_minmax(table->data, table, write,
|
| 966 | buffer, lenp, ppos, convmul, convdiv);
|
| 967 | }
|
| 968 |
|
| 969 | |
| 970 | * proc_doulongvec_minmax - read a vector of long integers with min/max values
|
| 971 | * @table: the sysctl table
|
| 972 | * @write: %TRUE if this is a write to the sysctl file
|
| 973 | * @buffer: the user buffer
|
| 974 | * @lenp: the size of the user buffer
|
| 975 | * @ppos: file position
|
| 976 | *
|
| 977 | * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
|
| 978 | * values from/to the user buffer, treated as an ASCII string.
|
| 979 | *
|
| 980 | * This routine will ensure the values are within the range specified by
|
| 981 | * table->extra1 (min) and table->extra2 (max).
|
| 982 | *
|
| 983 | * Returns 0 on success.
|
| 984 |
|
| 985 | int proc_doulongvec_minmax(const struct ctl_table *table, int write,
|
| 986 | void *buffer, size_t *lenp, loff_t *ppos)
|
| 987 | {
|
| 988 | return do_proc_doulongvec_minmax(table, write, buffer, lenp, ppos, 1l, 1l);
|
| 989 | }
|
| 990 |
|
| 991 | |
| 992 | * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
|
| 993 | * @table: the sysctl table
|
| 994 | * @write: %TRUE if this is a write to the sysctl file
|
| 995 | * @buffer: the user buffer
|
| 996 | * @lenp: the size of the user buffer
|
| 997 | * @ppos: file position
|
| 998 | *
|
| 999 | * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
|
| 1000 | * values from/to the user buffer, treated as an ASCII string. The values
|
| 1001 | * are treated as milliseconds, and converted to jiffies when they are stored.
|
| 1002 | *
|
| 1003 | * This routine will ensure the values are within the range specified by
|
| 1004 | * table->extra1 (min) and table->extra2 (max).
|
| 1005 | *
|
| 1006 | * Returns 0 on success.
|
| 1007 |
|
| 1008 | int proc_doulongvec_ms_jiffies_minmax(const struct ctl_table *table, int write,
|
| 1009 | void *buffer, size_t *lenp, loff_t *ppos)
|
| 1010 | {
|
| 1011 | return do_proc_doulongvec_minmax(table, write, buffer,
|
| 1012 | lenp, ppos, HZ, 1000l);
|
| 1013 | }
|
| 1014 |
|
| 1015 |
|
| 1016 | static int do_proc_dointvec_jiffies_conv(bool *negp, unsigned long *lvalp,
|
| 1017 | int *valp,
|
| 1018 | int write, void *data)
|
| 1019 | {
|
| 1020 | if (write) {
|
| 1021 | if (*lvalp > INT_MAX / HZ)
|
| 1022 | return 1;
|
| 1023 | if (*negp)
|
| 1024 | WRITE_ONCE(*valp, -*lvalp * HZ);
|
| 1025 | else
|
| 1026 | WRITE_ONCE(*valp, *lvalp * HZ);
|
| 1027 | } else {
|
| 1028 | int val = READ_ONCE(*valp);
|
| 1029 | unsigned long lval;
|
| 1030 | if (val < 0) {
|
| 1031 | *negp = true;
|
| 1032 | lval = -(unsigned long)val;
|
| 1033 | } else {
|
| 1034 | *negp = false;
|
| 1035 | lval = (unsigned long)val;
|
| 1036 | }
|
| 1037 | *lvalp = lval / HZ;
|
| 1038 | }
|
| 1039 | return 0;
|
| 1040 | }
|
| 1041 |
|
| 1042 | static int do_proc_dointvec_userhz_jiffies_conv(bool *negp, unsigned long *lvalp,
|
| 1043 | int *valp,
|
| 1044 | int write, void *data)
|
| 1045 | {
|
| 1046 | if (write) {
|
| 1047 | if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
|
| 1048 | return 1;
|
| 1049 | *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
|
| 1050 | } else {
|
| 1051 | int val = *valp;
|
| 1052 | unsigned long lval;
|
| 1053 | if (val < 0) {
|
| 1054 | *negp = true;
|
| 1055 | lval = -(unsigned long)val;
|
| 1056 | } else {
|
| 1057 | *negp = false;
|
| 1058 | lval = (unsigned long)val;
|
| 1059 | }
|
| 1060 | *lvalp = jiffies_to_clock_t(lval);
|
| 1061 | }
|
| 1062 | return 0;
|
| 1063 | }
|
| 1064 |
|
| 1065 | static int do_proc_dointvec_ms_jiffies_conv(bool *negp, unsigned long *lvalp,
|
| 1066 | int *valp,
|
| 1067 | int write, void *data)
|
| 1068 | {
|
| 1069 | if (write) {
|
| 1070 | unsigned long jif = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
|
| 1071 |
|
| 1072 | if (jif > INT_MAX)
|
| 1073 | return 1;
|
| 1074 | WRITE_ONCE(*valp, (int)jif);
|
| 1075 | } else {
|
| 1076 | int val = READ_ONCE(*valp);
|
| 1077 | unsigned long lval;
|
| 1078 | if (val < 0) {
|
| 1079 | *negp = true;
|
| 1080 | lval = -(unsigned long)val;
|
| 1081 | } else {
|
| 1082 | *negp = false;
|
| 1083 | lval = (unsigned long)val;
|
| 1084 | }
|
| 1085 | *lvalp = jiffies_to_msecs(lval);
|
| 1086 | }
|
| 1087 | return 0;
|
| 1088 | }
|
| 1089 |
|
| 1090 | static int do_proc_dointvec_ms_jiffies_minmax_conv(bool *negp, unsigned long *lvalp,
|
| 1091 | int *valp, int write, void *data)
|
| 1092 | {
|
| 1093 | int tmp, ret;
|
| 1094 | struct do_proc_dointvec_minmax_conv_param *param = data;
|
| 1095 | |
| 1096 | * If writing, first do so via a temporary local int so we can
|
| 1097 | * bounds-check it before touching *valp.
|
| 1098 |
|
| 1099 | int *ip = write ? &tmp : valp;
|
| 1100 |
|
| 1101 | ret = do_proc_dointvec_ms_jiffies_conv(negp, lvalp, ip, write, data);
|
| 1102 | if (ret)
|
| 1103 | return ret;
|
| 1104 |
|
| 1105 | if (write) {
|
| 1106 | if ((param->min && *param->min > tmp) ||
|
| 1107 | (param->max && *param->max < tmp))
|
| 1108 | return -EINVAL;
|
| 1109 | *valp = tmp;
|
| 1110 | }
|
| 1111 | return 0;
|
| 1112 | }
|
| 1113 |
|
| 1114 | |
| 1115 | * proc_dointvec_jiffies - read a vector of integers as seconds
|
| 1116 | * @table: the sysctl table
|
| 1117 | * @write: %TRUE if this is a write to the sysctl file
|
| 1118 | * @buffer: the user buffer
|
| 1119 | * @lenp: the size of the user buffer
|
| 1120 | * @ppos: file position
|
| 1121 | *
|
| 1122 | * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
|
| 1123 | * values from/to the user buffer, treated as an ASCII string.
|
| 1124 | * The values read are assumed to be in seconds, and are converted into
|
| 1125 | * jiffies.
|
| 1126 | *
|
| 1127 | * Returns 0 on success.
|
| 1128 |
|
| 1129 | int proc_dointvec_jiffies(const struct ctl_table *table, int write,
|
| 1130 | void *buffer, size_t *lenp, loff_t *ppos)
|
| 1131 | {
|
| 1132 | return do_proc_dointvec(table,write,buffer,lenp,ppos,
|
| 1133 | do_proc_dointvec_jiffies_conv,NULL);
|
| 1134 | }
|
| 1135 |
|
| 1136 | int proc_dointvec_ms_jiffies_minmax(const struct ctl_table *table, int write,
|
| 1137 | void *buffer, size_t *lenp, loff_t *ppos)
|
| 1138 | {
|
| 1139 | struct do_proc_dointvec_minmax_conv_param param = {
|
| 1140 | .min = (int *) table->extra1,
|
| 1141 | .max = (int *) table->extra2,
|
| 1142 | };
|
| 1143 | return do_proc_dointvec(table, write, buffer, lenp, ppos,
|
| 1144 | do_proc_dointvec_ms_jiffies_minmax_conv, ¶m);
|
| 1145 | }
|
| 1146 |
|
| 1147 | |
| 1148 | * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
|
| 1149 | * @table: the sysctl table
|
| 1150 | * @write: %TRUE if this is a write to the sysctl file
|
| 1151 | * @buffer: the user buffer
|
| 1152 | * @lenp: the size of the user buffer
|
| 1153 | * @ppos: pointer to the file position
|
| 1154 | *
|
| 1155 | * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
|
| 1156 | * values from/to the user buffer, treated as an ASCII string.
|
| 1157 | * The values read are assumed to be in 1/USER_HZ seconds, and
|
| 1158 | * are converted into jiffies.
|
| 1159 | *
|
| 1160 | * Returns 0 on success.
|
| 1161 |
|
| 1162 | int proc_dointvec_userhz_jiffies(const struct ctl_table *table, int write,
|
| 1163 | void *buffer, size_t *lenp, loff_t *ppos)
|
| 1164 | {
|
| 1165 | return do_proc_dointvec(table, write, buffer, lenp, ppos,
|
| 1166 | do_proc_dointvec_userhz_jiffies_conv, NULL);
|
| 1167 | }
|
| 1168 |
|
| 1169 | |
| 1170 | * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
|
| 1171 | * @table: the sysctl table
|
| 1172 | * @write: %TRUE if this is a write to the sysctl file
|
| 1173 | * @buffer: the user buffer
|
| 1174 | * @lenp: the size of the user buffer
|
| 1175 | * @ppos: the current position in the file
|
| 1176 | *
|
| 1177 | * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
|
| 1178 | * values from/to the user buffer, treated as an ASCII string.
|
| 1179 | * The values read are assumed to be in 1/1000 seconds, and
|
| 1180 | * are converted into jiffies.
|
| 1181 | *
|
| 1182 | * Returns 0 on success.
|
| 1183 |
|
| 1184 | int proc_dointvec_ms_jiffies(const struct ctl_table *table, int write, void *buffer,
|
| 1185 | size_t *lenp, loff_t *ppos)
|
| 1186 | {
|
| 1187 | return do_proc_dointvec(table, write, buffer, lenp, ppos,
|
| 1188 | do_proc_dointvec_ms_jiffies_conv, NULL);
|
| 1189 | }
|
| 1190 |
|
| 1191 | |
| 1192 | * proc_do_large_bitmap - read/write from/to a large bitmap
|
| 1193 | * @table: the sysctl table
|
| 1194 | * @write: %TRUE if this is a write to the sysctl file
|
| 1195 | * @buffer: the user buffer
|
| 1196 | * @lenp: the size of the user buffer
|
| 1197 | * @ppos: file position
|
| 1198 | *
|
| 1199 | * The bitmap is stored at table->data and the bitmap length (in bits)
|
| 1200 | * in table->maxlen.
|
| 1201 | *
|
| 1202 | * We use a range comma separated format (e.g. 1,3-4,10-10) so that
|
| 1203 | * large bitmaps may be represented in a compact manner. Writing into
|
| 1204 | * the file will clear the bitmap then update it with the given input.
|
| 1205 | *
|
| 1206 | * Returns 0 on success.
|
| 1207 |
|
| 1208 | int proc_do_large_bitmap(const struct ctl_table *table, int write,
|
| 1209 | void *buffer, size_t *lenp, loff_t *ppos)
|
| 1210 | {
|
| 1211 | int err = 0;
|
| 1212 | size_t left = *lenp;
|
| 1213 | unsigned long bitmap_len = table->maxlen;
|
| 1214 | unsigned long *bitmap = *(unsigned long **) table->data;
|
| 1215 | unsigned long *tmp_bitmap = NULL;
|
| 1216 | char tr_a[] = { '-', ',', '\n' }, tr_b[] = { ',', '\n', 0 }, c;
|
| 1217 |
|
| 1218 | if (!bitmap || !bitmap_len || !left || (*ppos && !write)) {
|
| 1219 | *lenp = 0;
|
| 1220 | return 0;
|
| 1221 | }
|
| 1222 |
|
| 1223 | if (write) {
|
| 1224 | char *p = buffer;
|
| 1225 | size_t skipped = 0;
|
| 1226 |
|
| 1227 | if (left > PAGE_SIZE - 1) {
|
| 1228 | left = PAGE_SIZE - 1;
|
| 1229 |
|
| 1230 | skipped = *lenp - left;
|
| 1231 | }
|
| 1232 |
|
| 1233 | tmp_bitmap = bitmap_zalloc(bitmap_len, GFP_KERNEL);
|
| 1234 | if (!tmp_bitmap)
|
| 1235 | return -ENOMEM;
|
| 1236 | proc_skip_char(&p, &left, '\n');
|
| 1237 | while (!err && left) {
|
| 1238 | unsigned long val_a, val_b;
|
| 1239 | bool neg;
|
| 1240 | size_t saved_left;
|
| 1241 |
|
| 1242 |
|
| 1243 | saved_left = left;
|
| 1244 | err = proc_get_long(&p, &left, &val_a, &neg, tr_a,
|
| 1245 | sizeof(tr_a), &c);
|
| 1246 | |
| 1247 | * If we consumed the entirety of a truncated buffer or
|
| 1248 | * only one char is left (may be a "-"), then stop here,
|
| 1249 | * reset, & come back for more.
|
| 1250 |
|
| 1251 | if ((left <= 1) && skipped) {
|
| 1252 | left = saved_left;
|
| 1253 | break;
|
| 1254 | }
|
| 1255 |
|
| 1256 | if (err)
|
| 1257 | break;
|
| 1258 | if (val_a >= bitmap_len || neg) {
|
| 1259 | err = -EINVAL;
|
| 1260 | break;
|
| 1261 | }
|
| 1262 |
|
| 1263 | val_b = val_a;
|
| 1264 | if (left) {
|
| 1265 | p++;
|
| 1266 | left--;
|
| 1267 | }
|
| 1268 |
|
| 1269 | if (c == '-') {
|
| 1270 | err = proc_get_long(&p, &left, &val_b,
|
| 1271 | &neg, tr_b, sizeof(tr_b),
|
| 1272 | &c);
|
| 1273 | |
| 1274 | * If we consumed all of a truncated buffer or
|
| 1275 | * then stop here, reset, & come back for more.
|
| 1276 |
|
| 1277 | if (!left && skipped) {
|
| 1278 | left = saved_left;
|
| 1279 | break;
|
| 1280 | }
|
| 1281 |
|
| 1282 | if (err)
|
| 1283 | break;
|
| 1284 | if (val_b >= bitmap_len || neg ||
|
| 1285 | val_a > val_b) {
|
| 1286 | err = -EINVAL;
|
| 1287 | break;
|
| 1288 | }
|
| 1289 | if (left) {
|
| 1290 | p++;
|
| 1291 | left--;
|
| 1292 | }
|
| 1293 | }
|
| 1294 |
|
| 1295 | bitmap_set(tmp_bitmap, val_a, val_b - val_a + 1);
|
| 1296 | proc_skip_char(&p, &left, '\n');
|
| 1297 | }
|
| 1298 | left += skipped;
|
| 1299 | } else {
|
| 1300 | unsigned long bit_a, bit_b = 0;
|
| 1301 | bool first = 1;
|
| 1302 |
|
| 1303 | while (left) {
|
| 1304 | bit_a = find_next_bit(bitmap, bitmap_len, bit_b);
|
| 1305 | if (bit_a >= bitmap_len)
|
| 1306 | break;
|
| 1307 | bit_b = find_next_zero_bit(bitmap, bitmap_len,
|
| 1308 | bit_a + 1) - 1;
|
| 1309 |
|
| 1310 | if (!first)
|
| 1311 | proc_put_char(&buffer, &left, ',');
|
| 1312 | proc_put_long(&buffer, &left, bit_a, false);
|
| 1313 | if (bit_a != bit_b) {
|
| 1314 | proc_put_char(&buffer, &left, '-');
|
| 1315 | proc_put_long(&buffer, &left, bit_b, false);
|
| 1316 | }
|
| 1317 |
|
| 1318 | first = 0; bit_b++;
|
| 1319 | }
|
| 1320 | proc_put_char(&buffer, &left, '\n');
|
| 1321 | }
|
| 1322 |
|
| 1323 | if (!err) {
|
| 1324 | if (write) {
|
| 1325 | if (*ppos)
|
| 1326 | bitmap_or(bitmap, bitmap, tmp_bitmap, bitmap_len);
|
| 1327 | else
|
| 1328 | bitmap_copy(bitmap, tmp_bitmap, bitmap_len);
|
| 1329 | }
|
| 1330 | *lenp -= left;
|
| 1331 | *ppos += *lenp;
|
| 1332 | }
|
| 1333 |
|
| 1334 | bitmap_free(tmp_bitmap);
|
| 1335 | return err;
|
| 1336 | }
|
| 1337 |
|
| 1338 | #else
|
| 1339 |
|
| 1340 | int proc_dostring(const struct ctl_table *table, int write,
|
| 1341 | void *buffer, size_t *lenp, loff_t *ppos)
|
| 1342 | {
|
| 1343 | return -ENOSYS;
|
| 1344 | }
|
| 1345 |
|
| 1346 | int proc_dobool(const struct ctl_table *table, int write,
|
| 1347 | void *buffer, size_t *lenp, loff_t *ppos)
|
| 1348 | {
|
| 1349 | return -ENOSYS;
|
| 1350 | }
|
| 1351 |
|
| 1352 | int proc_dointvec(const struct ctl_table *table, int write,
|
| 1353 | void *buffer, size_t *lenp, loff_t *ppos)
|
| 1354 | {
|
| 1355 | return -ENOSYS;
|
| 1356 | }
|
| 1357 |
|
| 1358 | int proc_douintvec(const struct ctl_table *table, int write,
|
| 1359 | void *buffer, size_t *lenp, loff_t *ppos)
|
| 1360 | {
|
| 1361 | return -ENOSYS;
|
| 1362 | }
|
| 1363 |
|
| 1364 | int proc_dointvec_minmax(const struct ctl_table *table, int write,
|
| 1365 | void *buffer, size_t *lenp, loff_t *ppos)
|
| 1366 | {
|
| 1367 | return -ENOSYS;
|
| 1368 | }
|
| 1369 |
|
| 1370 | int proc_douintvec_minmax(const struct ctl_table *table, int write,
|
| 1371 | void *buffer, size_t *lenp, loff_t *ppos)
|
| 1372 | {
|
| 1373 | return -ENOSYS;
|
| 1374 | }
|
| 1375 |
|
| 1376 | int proc_dou8vec_minmax(const struct ctl_table *table, int write,
|
| 1377 | void *buffer, size_t *lenp, loff_t *ppos)
|
| 1378 | {
|
| 1379 | return -ENOSYS;
|
| 1380 | }
|
| 1381 |
|
| 1382 | int proc_dointvec_jiffies(const struct ctl_table *table, int write,
|
| 1383 | void *buffer, size_t *lenp, loff_t *ppos)
|
| 1384 | {
|
| 1385 | return -ENOSYS;
|
| 1386 | }
|
| 1387 |
|
| 1388 | int proc_dointvec_ms_jiffies_minmax(const struct ctl_table *table, int write,
|
| 1389 | void *buffer, size_t *lenp, loff_t *ppos)
|
| 1390 | {
|
| 1391 | return -ENOSYS;
|
| 1392 | }
|
| 1393 |
|
| 1394 | int proc_dointvec_userhz_jiffies(const struct ctl_table *table, int write,
|
| 1395 | void *buffer, size_t *lenp, loff_t *ppos)
|
| 1396 | {
|
| 1397 | return -ENOSYS;
|
| 1398 | }
|
| 1399 |
|
| 1400 | int proc_dointvec_ms_jiffies(const struct ctl_table *table, int write,
|
| 1401 | void *buffer, size_t *lenp, loff_t *ppos)
|
| 1402 | {
|
| 1403 | return -ENOSYS;
|
| 1404 | }
|
| 1405 |
|
| 1406 | int proc_doulongvec_minmax(const struct ctl_table *table, int write,
|
| 1407 | void *buffer, size_t *lenp, loff_t *ppos)
|
| 1408 | {
|
| 1409 | return -ENOSYS;
|
| 1410 | }
|
| 1411 |
|
| 1412 | int proc_doulongvec_ms_jiffies_minmax(const struct ctl_table *table, int write,
|
| 1413 | void *buffer, size_t *lenp, loff_t *ppos)
|
| 1414 | {
|
| 1415 | return -ENOSYS;
|
| 1416 | }
|
| 1417 |
|
| 1418 | int proc_do_large_bitmap(const struct ctl_table *table, int write,
|
| 1419 | void *buffer, size_t *lenp, loff_t *ppos)
|
| 1420 | {
|
| 1421 | return -ENOSYS;
|
| 1422 | }
|
| 1423 |
|
| 1424 | #endif
|
| 1425 |
|
| 1426 | #if defined(CONFIG_SYSCTL)
|
| 1427 | int proc_do_static_key(const struct ctl_table *table, int write,
|
| 1428 | void *buffer, size_t *lenp, loff_t *ppos)
|
| 1429 | {
|
| 1430 | struct static_key *key = (struct static_key *)table->data;
|
| 1431 | static DEFINE_MUTEX(static_key_mutex);
|
| 1432 | int val, ret;
|
| 1433 | struct ctl_table tmp = {
|
| 1434 | .data = &val,
|
| 1435 | .maxlen = sizeof(val),
|
| 1436 | .mode = table->mode,
|
| 1437 | .extra1 = SYSCTL_ZERO,
|
| 1438 | .extra2 = SYSCTL_ONE,
|
| 1439 | };
|
| 1440 |
|
| 1441 | if (write && !capable(CAP_SYS_ADMIN))
|
| 1442 | return -EPERM;
|
| 1443 |
|
| 1444 | mutex_lock(&static_key_mutex);
|
| 1445 | val = static_key_enabled(key);
|
| 1446 | ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
|
| 1447 | if (write && !ret) {
|
| 1448 | if (val)
|
| 1449 | static_key_enable(key);
|
| 1450 | else
|
| 1451 | static_key_disable(key);
|
| 1452 | }
|
| 1453 | mutex_unlock(&static_key_mutex);
|
| 1454 | return ret;
|
| 1455 | }
|
| 1456 |
|
| 1457 | static const struct ctl_table sysctl_subsys_table[] = {
|
| 1458 | #ifdef CONFIG_PROC_SYSCTL
|
| 1459 | {
|
| 1460 | .procname = "sysctl_writes_strict",
|
| 1461 | .data = &sysctl_writes_strict,
|
| 1462 | .maxlen = sizeof(int),
|
| 1463 | .mode = 0644,
|
| 1464 | .proc_handler = proc_dointvec_minmax,
|
| 1465 | .extra1 = SYSCTL_NEG_ONE,
|
| 1466 | .extra2 = SYSCTL_ONE,
|
| 1467 | },
|
| 1468 | #endif
|
| 1469 | {
|
| 1470 | .procname = "ngroups_max",
|
| 1471 | .data = (void *)&ngroups_max,
|
| 1472 | .maxlen = sizeof (int),
|
| 1473 | .mode = 0444,
|
| 1474 | .proc_handler = proc_dointvec,
|
| 1475 | },
|
| 1476 | {
|
| 1477 | .procname = "cap_last_cap",
|
| 1478 | .data = (void *)&cap_last_cap,
|
| 1479 | .maxlen = sizeof(int),
|
| 1480 | .mode = 0444,
|
| 1481 | .proc_handler = proc_dointvec,
|
| 1482 | },
|
| 1483 | #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW
|
| 1484 | {
|
| 1485 | .procname = "unaligned-trap",
|
| 1486 | .data = &unaligned_enabled,
|
| 1487 | .maxlen = sizeof(int),
|
| 1488 | .mode = 0644,
|
| 1489 | .proc_handler = proc_dointvec,
|
| 1490 | },
|
| 1491 | #endif
|
| 1492 | #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN
|
| 1493 | {
|
| 1494 | .procname = "ignore-unaligned-usertrap",
|
| 1495 | .data = &no_unaligned_warning,
|
| 1496 | .maxlen = sizeof (int),
|
| 1497 | .mode = 0644,
|
| 1498 | .proc_handler = proc_dointvec,
|
| 1499 | },
|
| 1500 | #endif
|
| 1501 | };
|
| 1502 |
|
| 1503 | int __init sysctl_init_bases(void)
|
| 1504 | {
|
| 1505 | register_sysctl_init("kernel", sysctl_subsys_table);
|
| 1506 |
|
| 1507 | return 0;
|
| 1508 | }
|
| 1509 | #endif
|
| 1510 | |
| 1511 | * No sense putting this after each symbol definition, twice,
|
| 1512 | * exception granted :-)
|
| 1513 |
|
| 1514 | EXPORT_SYMBOL(proc_dobool);
|
| 1515 | EXPORT_SYMBOL(proc_dointvec);
|
| 1516 | EXPORT_SYMBOL(proc_douintvec);
|
| 1517 | EXPORT_SYMBOL(proc_dointvec_jiffies);
|
| 1518 | EXPORT_SYMBOL(proc_dointvec_minmax);
|
| 1519 | EXPORT_SYMBOL_GPL(proc_douintvec_minmax);
|
| 1520 | EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
|
| 1521 | EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
|
| 1522 | EXPORT_SYMBOL(proc_dostring);
|
| 1523 | EXPORT_SYMBOL(proc_doulongvec_minmax);
|
| 1524 | EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
|
| 1525 | EXPORT_SYMBOL(proc_do_large_bitmap);
|