linux/kernel/sysctl_binary.c

186 lines
4.1 KiB
C
Raw Normal View History

#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>
static int deprecated_sysctl_warning(struct __sysctl_args *args);
#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(int __user *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;
if (get_user(n, name))
return -EFAULT;
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;
}
int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen)
{
struct ctl_table_header *head;
int error = -ENOTDIR;
if (nlen <= 0 || nlen >= CTL_MAXNAME)
return -ENOTDIR;
if (oldval) {
int old_len;
if (!oldlenp || get_user(old_len, oldlenp))
return -EFAULT;
}
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;
}
SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
{
struct __sysctl_args tmp;
int error;
if (copy_from_user(&tmp, args, sizeof(tmp)))
return -EFAULT;
error = deprecated_sysctl_warning(&tmp);
if (error)
goto out;
lock_kernel();
error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
tmp.newval, tmp.newlen);
unlock_kernel();
out:
return error;
}
#else /* CONFIG_SYSCTL_SYSCALL */
SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
{
struct __sysctl_args tmp;
int error;
if (copy_from_user(&tmp, args, sizeof(tmp)))
return -EFAULT;
error = deprecated_sysctl_warning(&tmp);
/* If no error reading the parameters then just -ENOSYS ... */
if (!error)
error = -ENOSYS;
return error;
}
#endif /* CONFIG_SYSCTL_SYSCALL */
static int deprecated_sysctl_warning(struct __sysctl_args *args)
{
static int msg_count;
int name[CTL_MAXNAME];
int i;
/* Check args->nlen. */
if (args->nlen < 0 || args->nlen > CTL_MAXNAME)
return -ENOTDIR;
/* Read in the sysctl name for better debug message logging */
for (i = 0; i < args->nlen; i++)
if (get_user(name[i], args->name + i))
return -EFAULT;
/* Ignore accesses to kernel.version */
if ((args->nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
return 0;
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 < args->nlen; i++)
printk("%d.", name[i]);
printk("\n");
}
return 0;
}