1 // SPDX-License-Identifier: GPL-2.0-only
27 const int sysctl_vals[] = { 0, 1, 2, 3, 4, 100, 200, 1000, 3000, INT_MAX, 65535, -1 };
42  * enum sysctl_writes_mode - supported sysctl write modes
61 	SYSCTL_WRITES_LEGACY		= -1,
91 			if (len > maxlen - 1)  in _proc_do_string()
92 				len = maxlen - 1;  in _proc_do_string()
104 		while ((p - buffer) < *lenp && len < maxlen - 1) {  in _proc_do_string()
122 		len  -= *ppos;  in _proc_do_string()
142 		"warning, set kernel.sysctl_writes_strict = -1\n",  in warn_sysctl_write()
143 		current->comm, table->procname);  in warn_sysctl_write()
147  * proc_first_pos_non_zero_ignore - check if first position is allowed
151  * Returns true if the first position is non-zero and the sysctl_writes_strict
173  * proc_dostring - read a string sysctl
182  * string is truncated. The copied string is %NULL-terminated.
195 	return _proc_do_string(table->data, table->maxlen, write, buffer, lenp,  in proc_dostring()
204 		(*size)--;  in proc_skip_spaces()
214 		(*size)--;  in proc_skip_char()
220  * strtoul_lenient - parse an ASCII formatted integer from a buffer and only
243 		return -ERANGE;  in strtoul_lenient()
256  * proc_get_long - reads an ASCII formatted integer from a user buffer
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
279 		return -EINVAL;  in proc_get_long()
281 	if (len > TMPBUFLEN - 1)  in proc_get_long()
282 		len = TMPBUFLEN - 1;  in proc_get_long()
288 	if (*p == '-' && *size > 1) {  in proc_get_long()
294 		return -EINVAL;  in proc_get_long()
297 		return -EINVAL;  in proc_get_long()
299 	len = p - tmp;  in proc_get_long()
304 	if (len == TMPBUFLEN - 1)  in proc_get_long()
305 		return -EINVAL;  in proc_get_long()
308 		return -EINVAL;  in proc_get_long()
314 	*size -= len;  in proc_get_long()
320  * proc_put_long - converts an integer to a decimal ASCII formatted string
335 	sprintf(p, "%s%lu", neg ? "-" : "", val);  in proc_put_long()
340 	*size -= len;  in proc_put_long()
351 		(*size)--;  in proc_put_char()
364 				return -EINVAL;  in do_proc_dointvec_conv()
365 			WRITE_ONCE(*valp, -*lvalp);  in do_proc_dointvec_conv()
368 				return -EINVAL;  in do_proc_dointvec_conv()
375 			*lvalp = -(unsigned long)val;  in do_proc_dointvec_conv()
390 			return -EINVAL;  in do_proc_douintvec_conv()
409 	size_t left;  in __do_proc_dointvec()  local
412 	if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {  in __do_proc_dointvec()
418 	vleft = table->maxlen / sizeof(*i);  in __do_proc_dointvec()
419 	left = *lenp;  in __do_proc_dointvec()
428 		if (left > PAGE_SIZE - 1)  in __do_proc_dointvec()
429 			left = PAGE_SIZE - 1;  in __do_proc_dointvec()
433 	for (; left && vleft--; i++, first=0) {  in __do_proc_dointvec()
438 			proc_skip_spaces(&p, &left);  in __do_proc_dointvec()
440 			if (!left)  in __do_proc_dointvec()
442 			err = proc_get_long(&p, &left, &lval, &neg,  in __do_proc_dointvec()
448 				err = -EINVAL;  in __do_proc_dointvec()
453 				err = -EINVAL;  in __do_proc_dointvec()
457 				proc_put_char(&buffer, &left, '\t');  in __do_proc_dointvec()
458 			proc_put_long(&buffer, &left, lval, neg);  in __do_proc_dointvec()
462 	if (!write && !first && left && !err)  in __do_proc_dointvec()
463 		proc_put_char(&buffer, &left, '\n');  in __do_proc_dointvec()
464 	if (write && !err && left)  in __do_proc_dointvec()
465 		proc_skip_spaces(&p, &left);  in __do_proc_dointvec()
467 		return err ? : -EINVAL;  in __do_proc_dointvec()
468 	*lenp -= left;  in __do_proc_dointvec()
480 	return __do_proc_dointvec(table->data, table, write,  in do_proc_dointvec()
495 	size_t left;  in do_proc_douintvec_w()  local
499 	left = *lenp;  in do_proc_douintvec_w()
504 	if (left > PAGE_SIZE - 1)  in do_proc_douintvec_w()
505 		left = PAGE_SIZE - 1;  in do_proc_douintvec_w()
507 	proc_skip_spaces(&p, &left);  in do_proc_douintvec_w()
508 	if (!left) {  in do_proc_douintvec_w()
509 		err = -EINVAL;  in do_proc_douintvec_w()
513 	err = proc_get_long(&p, &left, &lval, &neg,  in do_proc_douintvec_w()
517 		err = -EINVAL;  in do_proc_douintvec_w()
522 		err = -EINVAL;  in do_proc_douintvec_w()
526 	if (!err && left)  in do_proc_douintvec_w()
527 		proc_skip_spaces(&p, &left);  in do_proc_douintvec_w()
531 		return -EINVAL;  in do_proc_douintvec_w()
550 	size_t left;  in do_proc_douintvec_r()  local
552 	left = *lenp;  in do_proc_douintvec_r()
555 		err = -EINVAL;  in do_proc_douintvec_r()
559 	proc_put_long(&buffer, &left, lval, false);  in do_proc_douintvec_r()
560 	if (!left)  in do_proc_douintvec_r()
563 	proc_put_char(&buffer, &left, '\n');  in do_proc_douintvec_r()
566 	*lenp -= left;  in do_proc_douintvec_r()
582 	if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {  in __do_proc_douintvec()
588 	vleft = table->maxlen / sizeof(*i);  in __do_proc_douintvec()
596 		return -EINVAL;  in __do_proc_douintvec()
615 	return __do_proc_douintvec(table->data, table, write,  in do_proc_douintvec()
620  * proc_dobool - read/write a bool
630  * table->data must point to a bool variable and table->maxlen must
639 	bool *data = table->data;  in proc_dobool()
643 	if (table->maxlen != sizeof(bool))  in proc_dobool()
644 		return -EINVAL;  in proc_dobool()
660  * proc_dointvec - read a vector of integers
667  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
679  * proc_douintvec - read a vector of unsigned integers
686  * Reads/writes up to table->maxlen/sizeof(unsigned int) unsigned integer
699  * struct do_proc_dointvec_minmax_conv_param - proc_dointvec_minmax() range checking structure
720 	 * bounds-check it before touching *valp.  in do_proc_dointvec_minmax_conv()
729 		if ((param->min && *param->min > tmp) ||  in do_proc_dointvec_minmax_conv()
730 		    (param->max && *param->max < tmp))  in do_proc_dointvec_minmax_conv()
731 			return -EINVAL;  in do_proc_dointvec_minmax_conv()
739  * proc_dointvec_minmax - read a vector of integers with min/max values
746  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
750  * table->extra1 (min) and table->extra2 (max).
752  * Returns 0 on success or -EINVAL on write when the range check fails.
758 		.min = (int *) table->extra1,  in proc_dointvec_minmax()
759 		.max = (int *) table->extra2,  in proc_dointvec_minmax()
766  * struct do_proc_douintvec_minmax_conv_param - proc_douintvec_minmax() range checking structure
786 	/* write via temporary local uint for bounds-checking */  in do_proc_douintvec_minmax_conv()
794 		if ((param->min && *param->min > tmp) ||  in do_proc_douintvec_minmax_conv()
795 		    (param->max && *param->max < tmp))  in do_proc_douintvec_minmax_conv()
796 			return -ERANGE;  in do_proc_douintvec_minmax_conv()
805  * proc_douintvec_minmax - read a vector of unsigned ints with min/max values
812  * Reads/writes up to table->maxlen/sizeof(unsigned int) unsigned integer
817  * table->extra1 (min) and table->extra2 (max). There is a final sanity
821  * Returns 0 on success or -ERANGE on write when the range check fails.
827 		.min = (unsigned int *) table->extra1,  in proc_douintvec_minmax()
828 		.max = (unsigned int *) table->extra2,  in proc_douintvec_minmax()
835  * proc_dou8vec_minmax - read a vector of unsigned chars with min/max values
842  * Reads/writes up to table->maxlen/sizeof(u8) unsigned chars
847  * table->extra1 (min) and table->extra2 (max).
856 	u8 *data = table->data;  in proc_dou8vec_minmax()
864 	if (table->maxlen != sizeof(u8))  in proc_dou8vec_minmax()
865 		return -EINVAL;  in proc_dou8vec_minmax()
867 	if (table->extra1)  in proc_dou8vec_minmax()
868 		min = *(unsigned int *) table->extra1;  in proc_dou8vec_minmax()
869 	if (table->extra2)  in proc_dou8vec_minmax()
870 		max = *(unsigned int *) table->extra2;  in proc_dou8vec_minmax()
894 	size_t left;  in __do_proc_doulongvec_minmax()  local
897 	if (!data || !table->maxlen || !*lenp || (*ppos && !write)) {  in __do_proc_doulongvec_minmax()
903 	min = table->extra1;  in __do_proc_doulongvec_minmax()
904 	max = table->extra2;  in __do_proc_doulongvec_minmax()
905 	vleft = table->maxlen / sizeof(unsigned long);  in __do_proc_doulongvec_minmax()
906 	left = *lenp;  in __do_proc_doulongvec_minmax()
912 		if (left > PAGE_SIZE - 1)  in __do_proc_doulongvec_minmax()
913 			left = PAGE_SIZE - 1;  in __do_proc_doulongvec_minmax()
917 	for (; left && vleft--; i++, first = 0) {  in __do_proc_doulongvec_minmax()
923 			proc_skip_spaces(&p, &left);  in __do_proc_doulongvec_minmax()
924 			if (!left)  in __do_proc_doulongvec_minmax()
927 			err = proc_get_long(&p, &left, &val, &neg,  in __do_proc_doulongvec_minmax()
931 				err = -EINVAL;  in __do_proc_doulongvec_minmax()
937 				err = -EINVAL;  in __do_proc_doulongvec_minmax()
944 				proc_put_char(&buffer, &left, '\t');  in __do_proc_doulongvec_minmax()
945 			proc_put_long(&buffer, &left, val, false);  in __do_proc_doulongvec_minmax()
949 	if (!write && !first && left && !err)  in __do_proc_doulongvec_minmax()
950 		proc_put_char(&buffer, &left, '\n');  in __do_proc_doulongvec_minmax()
952 		proc_skip_spaces(&p, &left);  in __do_proc_doulongvec_minmax()
954 		return err ? : -EINVAL;  in __do_proc_doulongvec_minmax()
955 	*lenp -= left;  in __do_proc_doulongvec_minmax()
965 	return __do_proc_doulongvec_minmax(table->data, table, write,  in do_proc_doulongvec_minmax()
970  * proc_doulongvec_minmax - read a vector of long integers with min/max values
977  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
981  * table->extra1 (min) and table->extra2 (max).
992  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
999  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
1004  * table->extra1 (min) and table->extra2 (max).
1024 			WRITE_ONCE(*valp, -*lvalp * HZ);  in do_proc_dointvec_jiffies_conv()
1032 			lval = -(unsigned long)val;  in do_proc_dointvec_jiffies_conv()
1049 		*valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);  in do_proc_dointvec_userhz_jiffies_conv()
1055 			lval = -(unsigned long)val;  in do_proc_dointvec_userhz_jiffies_conv()
1070 		unsigned long jif = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);  in do_proc_dointvec_ms_jiffies_conv()
1080 			lval = -(unsigned long)val;  in do_proc_dointvec_ms_jiffies_conv()
1097 	 * bounds-check it before touching *valp.  in do_proc_dointvec_ms_jiffies_minmax_conv()
1106 		if ((param->min && *param->min > tmp) ||  in do_proc_dointvec_ms_jiffies_minmax_conv()
1107 				(param->max && *param->max < tmp))  in do_proc_dointvec_ms_jiffies_minmax_conv()
1108 			return -EINVAL;  in do_proc_dointvec_ms_jiffies_minmax_conv()
1115  * proc_dointvec_jiffies - read a vector of integers as seconds
1122  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1140 		.min = (int *) table->extra1,  in proc_dointvec_ms_jiffies_minmax()
1141 		.max = (int *) table->extra2,  in proc_dointvec_ms_jiffies_minmax()
1148  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
1155  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1170  * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
1177  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1192  * proc_do_large_bitmap - read/write from/to a large bitmap
1199  * The bitmap is stored at table->data and the bitmap length (in bits)
1200  * in table->maxlen.
1202  * We use a range comma separated format (e.g. 1,3-4,10-10) so that
1212 	size_t left = *lenp;  in proc_do_large_bitmap()  local
1213 	unsigned long bitmap_len = table->maxlen;  in proc_do_large_bitmap()
1214 	unsigned long *bitmap = *(unsigned long **) table->data;  in proc_do_large_bitmap()
1216 	char tr_a[] = { '-', ',', '\n' }, tr_b[] = { ',', '\n', 0 }, c;  in proc_do_large_bitmap()
1218 	if (!bitmap || !bitmap_len || !left || (*ppos && !write)) {  in proc_do_large_bitmap()
1227 		if (left > PAGE_SIZE - 1) {  in proc_do_large_bitmap()
1228 			left = PAGE_SIZE - 1;  in proc_do_large_bitmap()
1230 			skipped = *lenp - left;  in proc_do_large_bitmap()
1235 			return -ENOMEM;  in proc_do_large_bitmap()
1236 		proc_skip_char(&p, &left, '\n');  in proc_do_large_bitmap()
1237 		while (!err && left) {  in proc_do_large_bitmap()
1242 			/* In case we stop parsing mid-number, we can reset */  in proc_do_large_bitmap()
1243 			saved_left = left;  in proc_do_large_bitmap()
1244 			err = proc_get_long(&p, &left, &val_a, &neg, tr_a,  in proc_do_large_bitmap()
1248 			 * only one char is left (may be a "-"), then stop here,  in proc_do_large_bitmap()
1251 			if ((left <= 1) && skipped) {  in proc_do_large_bitmap()
1252 				left = saved_left;  in proc_do_large_bitmap()
1259 				err = -EINVAL;  in proc_do_large_bitmap()
1264 			if (left) {  in proc_do_large_bitmap()
1266 				left--;  in proc_do_large_bitmap()
1269 			if (c == '-') {  in proc_do_large_bitmap()
1270 				err = proc_get_long(&p, &left, &val_b,  in proc_do_large_bitmap()
1277 				if (!left && skipped) {  in proc_do_large_bitmap()
1278 					left = saved_left;  in proc_do_large_bitmap()
1286 					err = -EINVAL;  in proc_do_large_bitmap()
1289 				if (left) {  in proc_do_large_bitmap()
1291 					left--;  in proc_do_large_bitmap()
1295 			bitmap_set(tmp_bitmap, val_a, val_b - val_a + 1);  in proc_do_large_bitmap()
1296 			proc_skip_char(&p, &left, '\n');  in proc_do_large_bitmap()
1298 		left += skipped;  in proc_do_large_bitmap()
1303 		while (left) {  in proc_do_large_bitmap()
1308 						   bit_a + 1) - 1;  in proc_do_large_bitmap()
1311 				proc_put_char(&buffer, &left, ',');  in proc_do_large_bitmap()
1312 			proc_put_long(&buffer, &left, bit_a, false);  in proc_do_large_bitmap()
1314 				proc_put_char(&buffer, &left, '-');  in proc_do_large_bitmap()
1315 				proc_put_long(&buffer, &left, bit_b, false);  in proc_do_large_bitmap()
1320 		proc_put_char(&buffer, &left, '\n');  in proc_do_large_bitmap()
1330 		*lenp -= left;  in proc_do_large_bitmap()
1343 	return -ENOSYS;  in proc_dostring()
1349 	return -ENOSYS;  in proc_dobool()
1355 	return -ENOSYS;  in proc_dointvec()
1361 	return -ENOSYS;  in proc_douintvec()
1367 	return -ENOSYS;  in proc_dointvec_minmax()
1373 	return -ENOSYS;  in proc_douintvec_minmax()
1379 	return -ENOSYS;  in proc_dou8vec_minmax()
1385 	return -ENOSYS;  in proc_dointvec_jiffies()
1391 	return -ENOSYS;  in proc_dointvec_ms_jiffies_minmax()
1397 	return -ENOSYS;  in proc_dointvec_userhz_jiffies()
1403 	return -ENOSYS;  in proc_dointvec_ms_jiffies()
1409 	return -ENOSYS;  in proc_doulongvec_minmax()
1415 	return -ENOSYS;  in proc_doulongvec_ms_jiffies_minmax()
1421 	return -ENOSYS;  in proc_do_large_bitmap()
1430 	struct static_key *key = (struct static_key *)table->data;  in proc_do_static_key()
1436 		.mode   = table->mode,  in proc_do_static_key()
1442 		return -EPERM;  in proc_do_static_key()
1485 		.procname	= "unaligned-trap",
1494 		.procname	= "ignore-unaligned-usertrap",
1512  * exception granted :-)