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#include <linux/stat.h>
#include <linux/sysctl.h>
#include "../fs/xfs/linux-2.6/xfs_sysctl.h"
#include <linux/sunrpc/debug.h>
#include <linux/string.h>
#include <net/ip_vs.h>
#include <linux/syscalls.h>
#include <linux/namei.h>
#include <linux/mount.h>
#include <linux/fs.h>
#include <linux/nsproxy.h>
#include <linux/pid_namespace.h>
#include <linux/file.h>
#include <linux/ctype.h>
#include <linux/smp_lock.h>
#ifdef CONFIG_SYSCTL_SYSCALL
/* Perform the actual read/write of a sysctl table entry. */
static int do_sysctl_strategy(struct ctl_table_root *root,
struct ctl_table *table,
void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen)
{
int op = 0, rc;
if (oldval)
op |= MAY_READ;
if (newval)
op |= MAY_WRITE;
if (sysctl_perm(root, table, op))
return -EPERM;
if (table->strategy) {
rc = table->strategy(table, oldval, oldlenp, newval, newlen);
if (rc < 0)
return rc;
if (rc > 0)
return 0;
}
/* If there is no strategy routine, or if the strategy returns
* zero, proceed with automatic r/w */
if (table->data && table->maxlen) {
rc = sysctl_data(table, oldval, oldlenp, newval, newlen);
if (rc < 0)
return rc;
}
return 0;
}
static int parse_table(const int *name, int nlen,
void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen,
struct ctl_table_root *root,
struct ctl_table *table)
{
int n;
repeat:
if (!nlen)
return -ENOTDIR;
n = *name;
for ( ; table->ctl_name || table->procname; table++) {
if (!table->ctl_name)
continue;
if (n == table->ctl_name) {
int error;
if (table->child) {
if (sysctl_perm(root, table, MAY_EXEC))
return -EPERM;
name++;
nlen--;
table = table->child;
goto repeat;
}
error = do_sysctl_strategy(root, table,
oldval, oldlenp,
newval, newlen);
return error;
}
}
return -ENOTDIR;
}
static ssize_t binary_sysctl(const int *name, int nlen,
void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen)
{
struct ctl_table_header *head;
ssize_t error = -ENOTDIR;
for (head = sysctl_head_next(NULL); head;
head = sysctl_head_next(head)) {
error = parse_table(name, nlen, oldval, oldlenp,
newval, newlen,
head->root, head->ctl_table);
if (error != -ENOTDIR) {
sysctl_head_finish(head);
break;
}
}
return error;
}
#else /* CONFIG_SYSCTL_SYSCALL */
static ssize_t binary_sysctl(const int *ctl_name, int nlen,
void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen)
{
return -ENOSYS;
}
#endif /* CONFIG_SYSCTL_SYSCALL */
static void deprecated_sysctl_warning(const int *name, int nlen)
{
static int msg_count;
int i;
/* Ignore accesses to kernel.version */
if ((nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
return;
if (msg_count < 5) {
msg_count++;
printk(KERN_INFO
"warning: process `%s' used the deprecated sysctl "
"system call with ", current->comm);
for (i = 0; i < nlen; i++)
printk("%d.", name[i]);
printk("\n");
}
return;
}
static int do_sysctl(int __user *args_name, int nlen,
void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen)
{
int name[CTL_MAXNAME];
size_t oldlen = 0;
int i;
if (nlen <= 0 || nlen >= CTL_MAXNAME)
return -ENOTDIR;
if (oldval && !oldlenp)
return -EFAULT;
if (oldlenp && get_user(oldlen, oldlenp))
return -EFAULT;
/* Read in the sysctl name for simplicity */
for (i = 0; i < nlen; i++)
if (get_user(name[i], args_name + i))
return -EFAULT;
deprecated_sysctl_warning(name, nlen);
return binary_sysctl(name, nlen, oldval, oldlenp, newval, newlen);
}
SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
{
struct __sysctl_args tmp;
int error;
if (copy_from_user(&tmp, args, sizeof(tmp)))
return -EFAULT;
lock_kernel();
error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
tmp.newval, tmp.newlen);
unlock_kernel();
return error;
}
#ifdef CONFIG_COMPAT
#include <asm/compat.h>
struct compat_sysctl_args {
compat_uptr_t name;
int nlen;
compat_uptr_t oldval;
compat_uptr_t oldlenp;
compat_uptr_t newval;
compat_size_t newlen;
compat_ulong_t __unused[4];
};
asmlinkage long compat_sys_sysctl(struct compat_sysctl_args __user *args)
{
struct compat_sysctl_args tmp;
compat_size_t __user *compat_oldlenp;
size_t __user *oldlenp = NULL;
size_t oldlen = 0;
ssize_t result;
if (copy_from_user(&tmp, args, sizeof(tmp)))
return -EFAULT;
compat_oldlenp = compat_ptr(tmp.oldlenp);
if (compat_oldlenp) {
oldlenp = compat_alloc_user_space(sizeof(*compat_oldlenp));
if (get_user(oldlen, compat_oldlenp) ||
put_user(oldlen, oldlenp))
return -EFAULT;
}
lock_kernel();
result = do_sysctl(compat_ptr(tmp.name), tmp.nlen,
compat_ptr(tmp.oldval), oldlenp,
compat_ptr(tmp.newval), tmp.newlen);
unlock_kernel();
if (oldlenp && !result) {
if (get_user(oldlen, oldlenp) ||
put_user(oldlen, compat_oldlenp))
return -EFAULT;
}
return result;
}
#endif /* CONFIG_COMPAT */
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