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-rw-r--r--kernel/sysctl.c176
1 files changed, 97 insertions, 79 deletions
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index fd3364827ccf..d7ffdc59816a 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -38,6 +38,7 @@
38#include <linux/writeback.h> 38#include <linux/writeback.h>
39#include <linux/hugetlb.h> 39#include <linux/hugetlb.h>
40#include <linux/initrd.h> 40#include <linux/initrd.h>
41#include <linux/key.h>
41#include <linux/times.h> 42#include <linux/times.h>
42#include <linux/limits.h> 43#include <linux/limits.h>
43#include <linux/dcache.h> 44#include <linux/dcache.h>
@@ -144,12 +145,6 @@ extern int no_unaligned_warning;
144extern int max_lock_depth; 145extern int max_lock_depth;
145#endif 146#endif
146 147
147#ifdef CONFIG_SYSCTL_SYSCALL
148static int parse_table(int __user *, int, void __user *, size_t __user *,
149 void __user *, size_t, struct ctl_table *);
150#endif
151
152
153#ifdef CONFIG_PROC_SYSCTL 148#ifdef CONFIG_PROC_SYSCTL
154static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp, 149static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
155 void __user *buffer, size_t *lenp, loff_t *ppos); 150 void __user *buffer, size_t *lenp, loff_t *ppos);
@@ -809,6 +804,14 @@ static struct ctl_table kern_table[] = {
809 .proc_handler = &proc_dostring, 804 .proc_handler = &proc_dostring,
810 .strategy = &sysctl_string, 805 .strategy = &sysctl_string,
811 }, 806 },
807#ifdef CONFIG_KEYS
808 {
809 .ctl_name = CTL_UNNUMBERED,
810 .procname = "keys",
811 .mode = 0555,
812 .child = key_sysctls,
813 },
814#endif
812/* 815/*
813 * NOTE: do not add new entries to this table unless you have read 816 * NOTE: do not add new entries to this table unless you have read
814 * Documentation/sysctl/ctl_unnumbered.txt 817 * Documentation/sysctl/ctl_unnumbered.txt
@@ -1430,6 +1433,76 @@ void register_sysctl_root(struct ctl_table_root *root)
1430} 1433}
1431 1434
1432#ifdef CONFIG_SYSCTL_SYSCALL 1435#ifdef CONFIG_SYSCTL_SYSCALL
1436/* Perform the actual read/write of a sysctl table entry. */
1437static int do_sysctl_strategy(struct ctl_table_root *root,
1438 struct ctl_table *table,
1439 int __user *name, int nlen,
1440 void __user *oldval, size_t __user *oldlenp,
1441 void __user *newval, size_t newlen)
1442{
1443 int op = 0, rc;
1444
1445 if (oldval)
1446 op |= 004;
1447 if (newval)
1448 op |= 002;
1449 if (sysctl_perm(root, table, op))
1450 return -EPERM;
1451
1452 if (table->strategy) {
1453 rc = table->strategy(table, name, nlen, oldval, oldlenp,
1454 newval, newlen);
1455 if (rc < 0)
1456 return rc;
1457 if (rc > 0)
1458 return 0;
1459 }
1460
1461 /* If there is no strategy routine, or if the strategy returns
1462 * zero, proceed with automatic r/w */
1463 if (table->data && table->maxlen) {
1464 rc = sysctl_data(table, name, nlen, oldval, oldlenp,
1465 newval, newlen);
1466 if (rc < 0)
1467 return rc;
1468 }
1469 return 0;
1470}
1471
1472static int parse_table(int __user *name, int nlen,
1473 void __user *oldval, size_t __user *oldlenp,
1474 void __user *newval, size_t newlen,
1475 struct ctl_table_root *root,
1476 struct ctl_table *table)
1477{
1478 int n;
1479repeat:
1480 if (!nlen)
1481 return -ENOTDIR;
1482 if (get_user(n, name))
1483 return -EFAULT;
1484 for ( ; table->ctl_name || table->procname; table++) {
1485 if (!table->ctl_name)
1486 continue;
1487 if (n == table->ctl_name) {
1488 int error;
1489 if (table->child) {
1490 if (sysctl_perm(root, table, 001))
1491 return -EPERM;
1492 name++;
1493 nlen--;
1494 table = table->child;
1495 goto repeat;
1496 }
1497 error = do_sysctl_strategy(root, table, name, nlen,
1498 oldval, oldlenp,
1499 newval, newlen);
1500 return error;
1501 }
1502 }
1503 return -ENOTDIR;
1504}
1505
1433int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp, 1506int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1434 void __user *newval, size_t newlen) 1507 void __user *newval, size_t newlen)
1435{ 1508{
@@ -1447,7 +1520,8 @@ int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *ol
1447 for (head = sysctl_head_next(NULL); head; 1520 for (head = sysctl_head_next(NULL); head;
1448 head = sysctl_head_next(head)) { 1521 head = sysctl_head_next(head)) {
1449 error = parse_table(name, nlen, oldval, oldlenp, 1522 error = parse_table(name, nlen, oldval, oldlenp,
1450 newval, newlen, head->ctl_table); 1523 newval, newlen,
1524 head->root, head->ctl_table);
1451 if (error != -ENOTDIR) { 1525 if (error != -ENOTDIR) {
1452 sysctl_head_finish(head); 1526 sysctl_head_finish(head);
1453 break; 1527 break;
@@ -1493,84 +1567,22 @@ static int test_perm(int mode, int op)
1493 return -EACCES; 1567 return -EACCES;
1494} 1568}
1495 1569
1496int sysctl_perm(struct ctl_table *table, int op) 1570int sysctl_perm(struct ctl_table_root *root, struct ctl_table *table, int op)
1497{ 1571{
1498 int error; 1572 int error;
1573 int mode;
1574
1499 error = security_sysctl(table, op); 1575 error = security_sysctl(table, op);
1500 if (error) 1576 if (error)
1501 return error; 1577 return error;
1502 return test_perm(table->mode, op);
1503}
1504
1505#ifdef CONFIG_SYSCTL_SYSCALL
1506static int parse_table(int __user *name, int nlen,
1507 void __user *oldval, size_t __user *oldlenp,
1508 void __user *newval, size_t newlen,
1509 struct ctl_table *table)
1510{
1511 int n;
1512repeat:
1513 if (!nlen)
1514 return -ENOTDIR;
1515 if (get_user(n, name))
1516 return -EFAULT;
1517 for ( ; table->ctl_name || table->procname; table++) {
1518 if (!table->ctl_name)
1519 continue;
1520 if (n == table->ctl_name) {
1521 int error;
1522 if (table->child) {
1523 if (sysctl_perm(table, 001))
1524 return -EPERM;
1525 name++;
1526 nlen--;
1527 table = table->child;
1528 goto repeat;
1529 }
1530 error = do_sysctl_strategy(table, name, nlen,
1531 oldval, oldlenp,
1532 newval, newlen);
1533 return error;
1534 }
1535 }
1536 return -ENOTDIR;
1537}
1538 1578
1539/* Perform the actual read/write of a sysctl table entry. */ 1579 if (root->permissions)
1540int do_sysctl_strategy (struct ctl_table *table, 1580 mode = root->permissions(root, current->nsproxy, table);
1541 int __user *name, int nlen, 1581 else
1542 void __user *oldval, size_t __user *oldlenp, 1582 mode = table->mode;
1543 void __user *newval, size_t newlen)
1544{
1545 int op = 0, rc;
1546
1547 if (oldval)
1548 op |= 004;
1549 if (newval)
1550 op |= 002;
1551 if (sysctl_perm(table, op))
1552 return -EPERM;
1553 1583
1554 if (table->strategy) { 1584 return test_perm(mode, op);
1555 rc = table->strategy(table, name, nlen, oldval, oldlenp,
1556 newval, newlen);
1557 if (rc < 0)
1558 return rc;
1559 if (rc > 0)
1560 return 0;
1561 }
1562
1563 /* If there is no strategy routine, or if the strategy returns
1564 * zero, proceed with automatic r/w */
1565 if (table->data && table->maxlen) {
1566 rc = sysctl_data(table, name, nlen, oldval, oldlenp,
1567 newval, newlen);
1568 if (rc < 0)
1569 return rc;
1570 }
1571 return 0;
1572} 1585}
1573#endif /* CONFIG_SYSCTL_SYSCALL */
1574 1586
1575static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table) 1587static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
1576{ 1588{
@@ -1583,9 +1595,13 @@ static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
1583 1595
1584static __init int sysctl_init(void) 1596static __init int sysctl_init(void)
1585{ 1597{
1586 int err;
1587 sysctl_set_parent(NULL, root_table); 1598 sysctl_set_parent(NULL, root_table);
1588 err = sysctl_check_table(current->nsproxy, root_table); 1599#ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1600 {
1601 int err;
1602 err = sysctl_check_table(current->nsproxy, root_table);
1603 }
1604#endif
1589 return 0; 1605 return 0;
1590} 1606}
1591 1607
@@ -1712,10 +1728,12 @@ struct ctl_table_header *__register_sysctl_paths(
1712 header->unregistering = NULL; 1728 header->unregistering = NULL;
1713 header->root = root; 1729 header->root = root;
1714 sysctl_set_parent(NULL, header->ctl_table); 1730 sysctl_set_parent(NULL, header->ctl_table);
1731#ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1715 if (sysctl_check_table(namespaces, header->ctl_table)) { 1732 if (sysctl_check_table(namespaces, header->ctl_table)) {
1716 kfree(header); 1733 kfree(header);
1717 return NULL; 1734 return NULL;
1718 } 1735 }
1736#endif
1719 spin_lock(&sysctl_lock); 1737 spin_lock(&sysctl_lock);
1720 header_list = lookup_header_list(root, namespaces); 1738 header_list = lookup_header_list(root, namespaces);
1721 list_add_tail(&header->ctl_entry, header_list); 1739 list_add_tail(&header->ctl_entry, header_list);