blob: 600b33358ded97ea54e90b6cc39dafef8e03fa40 [file] [log] [blame]
/*
* sysctl.c: General linux system control interface
*
* Begun 24 March 1995, Stephen Tweedie
* Added /proc support, Dec 1995
* Added bdflush entry and intvec min/max checking, 2/23/96, Tom Dyas.
* Added hooks for /proc/sys/net (minor, minor patch), 96/4/1, Mike Shaver.
* Added kernel/java-{interpreter,appletviewer}, 96/5/10, Mike Shaver.
* Dynamic registration fixes, Stephen Tweedie.
* Added kswapd-interval, ctrl-alt-del, printk stuff, 1/8/97, Chris Horn.
* Made sysctl support optional via CONFIG_SYSCTL, 1/10/97, Chris
* Horn.
* Added proc_doulongvec_ms_jiffies_minmax, 09/08/99, Carlos H. Bauer.
* Added proc_doulongvec_minmax, 09/08/99, Carlos H. Bauer.
* Changed linked lists to use list.h instead of lists.h, 02/24/00, Bill
* Wendling.
* The list_for_each() macro wasn't appropriate for the sysctl loop.
* Removed it and replaced it with older style, 03/23/00, Bill Wendling
*/
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/swap.h>
#include <linux/slab.h>
#include <linux/sysctl.h>
#include <linux/proc_fs.h>
#include <linux/capability.h>
#include <linux/ctype.h>
#include <linux/utsname.h>
#include <linux/capability.h>
#include <linux/smp_lock.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/kobject.h>
#include <linux/net.h>
#include <linux/sysrq.h>
#include <linux/highuid.h>
#include <linux/writeback.h>
#include <linux/hugetlb.h>
#include <linux/security.h>
#include <linux/initrd.h>
#include <linux/times.h>
#include <linux/limits.h>
#include <linux/dcache.h>
#include <linux/syscalls.h>
#include <linux/nfs_fs.h>
#include <linux/acpi.h>
#include <asm/uaccess.h>
#include <asm/processor.h>
extern int proc_nr_files(ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos);
#ifdef CONFIG_X86
#include <asm/nmi.h>
#include <asm/stacktrace.h>
#endif
#if defined(CONFIG_SYSCTL)
/* External variables not in a header file. */
extern int C_A_D;
extern int sysctl_overcommit_memory;
extern int sysctl_overcommit_ratio;
extern int sysctl_panic_on_oom;
extern int max_threads;
extern int core_uses_pid;
extern int suid_dumpable;
extern char core_pattern[];
extern int pid_max;
extern int min_free_kbytes;
extern int printk_ratelimit_jiffies;
extern int printk_ratelimit_burst;
extern int pid_max_min, pid_max_max;
extern int sysctl_drop_caches;
extern int percpu_pagelist_fraction;
extern int compat_log;
/* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
static int maxolduid = 65535;
static int minolduid;
static int min_percpu_pagelist_fract = 8;
static int ngroups_max = NGROUPS_MAX;
#ifdef CONFIG_KMOD
extern char modprobe_path[];
#endif
#ifdef CONFIG_CHR_DEV_SG
extern int sg_big_buff;
#endif
#ifdef CONFIG_SYSVIPC
static int proc_ipc_dointvec(ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos);
static int proc_ipc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos);
#endif
#ifdef __sparc__
extern char reboot_command [];
extern int stop_a_enabled;
extern int scons_pwroff;
#endif
#ifdef __hppa__
extern int pwrsw_enabled;
extern int unaligned_enabled;
#endif
#ifdef CONFIG_S390
#ifdef CONFIG_MATHEMU
extern int sysctl_ieee_emulation_warnings;
#endif
extern int sysctl_userprocess_debug;
extern int spin_retry;
#endif
extern int sysctl_hz_timer;
#ifdef CONFIG_BSD_PROCESS_ACCT
extern int acct_parm[];
#endif
#ifdef CONFIG_IA64
extern int no_unaligned_warning;
#endif
#ifdef CONFIG_RT_MUTEXES
extern int max_lock_depth;
#endif
#ifdef CONFIG_SYSCTL_SYSCALL
static int parse_table(int __user *, int, void __user *, size_t __user *,
void __user *, size_t, ctl_table *);
#endif
static int proc_do_uts_string(ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos);
static int sysctl_uts_string(ctl_table *table, int __user *name, int nlen,
void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen);
#ifdef CONFIG_SYSVIPC
static int sysctl_ipc_data(ctl_table *table, int __user *name, int nlen,
void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen);
#endif
#ifdef CONFIG_PROC_SYSCTL
static int proc_do_cad_pid(ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos);
#endif
static ctl_table root_table[];
static struct ctl_table_header root_table_header =
{ root_table, LIST_HEAD_INIT(root_table_header.ctl_entry) };
static ctl_table kern_table[];
static ctl_table vm_table[];
static ctl_table fs_table[];
static ctl_table debug_table[];
static ctl_table dev_table[];
extern ctl_table random_table[];
#ifdef CONFIG_UNIX98_PTYS
extern ctl_table pty_table[];
#endif
#ifdef CONFIG_INOTIFY_USER
extern ctl_table inotify_table[];
#endif
#ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
int sysctl_legacy_va_layout;
#endif
static void *get_uts(ctl_table *table, int write)
{
char *which = table->data;
#ifdef CONFIG_UTS_NS
struct uts_namespace *uts_ns = current->nsproxy->uts_ns;
which = (which - (char *)&init_uts_ns) + (char *)uts_ns;
#endif
if (!write)
down_read(&uts_sem);
else
down_write(&uts_sem);
return which;
}
static void put_uts(ctl_table *table, int write, void *which)
{
if (!write)
up_read(&uts_sem);
else
up_write(&uts_sem);
}
#ifdef CONFIG_SYSVIPC
static void *get_ipc(ctl_table *table, int write)
{
char *which = table->data;
struct ipc_namespace *ipc_ns = current->nsproxy->ipc_ns;
which = (which - (char *)&init_ipc_ns) + (char *)ipc_ns;
return which;
}
#else
#define get_ipc(T,W) ((T)->data)
#endif
/* /proc declarations: */
#ifdef CONFIG_PROC_SYSCTL
static ssize_t proc_readsys(struct file *, char __user *, size_t, loff_t *);
static ssize_t proc_writesys(struct file *, const char __user *, size_t, loff_t *);
static int proc_opensys(struct inode *, struct file *);
const struct file_operations proc_sys_file_operations = {
.open = proc_opensys,
.read = proc_readsys,
.write = proc_writesys,
};
extern struct proc_dir_entry *proc_sys_root;
static void register_proc_table(ctl_table *, struct proc_dir_entry *, void *);
static void unregister_proc_table(ctl_table *, struct proc_dir_entry *);
#endif
/* The default sysctl tables: */
static ctl_table root_table[] = {
{
.ctl_name = CTL_KERN,
.procname = "kernel",
.mode = 0555,
.child = kern_table,
},
{
.ctl_name = CTL_VM,
.procname = "vm",
.mode = 0555,
.child = vm_table,
},
#ifdef CONFIG_NET
{
.ctl_name = CTL_NET,
.procname = "net",
.mode = 0555,
.child = net_table,
},
#endif
{
.ctl_name = CTL_FS,
.procname = "fs",
.mode = 0555,
.child = fs_table,
},
{
.ctl_name = CTL_DEBUG,
.procname = "debug",
.mode = 0555,
.child = debug_table,
},
{
.ctl_name = CTL_DEV,
.procname = "dev",
.mode = 0555,
.child = dev_table,
},
{ .ctl_name = 0 }
};
static ctl_table kern_table[] = {
{
.ctl_name = KERN_OSTYPE,
.procname = "ostype",
.data = init_uts_ns.name.sysname,
.maxlen = sizeof(init_uts_ns.name.sysname),
.mode = 0444,
.proc_handler = &proc_do_uts_string,
.strategy = &sysctl_uts_string,
},
{
.ctl_name = KERN_OSRELEASE,
.procname = "osrelease",
.data = init_uts_ns.name.release,
.maxlen = sizeof(init_uts_ns.name.release),
.mode = 0444,
.proc_handler = &proc_do_uts_string,
.strategy = &sysctl_uts_string,
},
{
.ctl_name = KERN_VERSION,
.procname = "version",
.data = init_uts_ns.name.version,
.maxlen = sizeof(init_uts_ns.name.version),
.mode = 0444,
.proc_handler = &proc_do_uts_string,
.strategy = &sysctl_uts_string,
},
{
.ctl_name = KERN_NODENAME,
.procname = "hostname",
.data = init_uts_ns.name.nodename,
.maxlen = sizeof(init_uts_ns.name.nodename),
.mode = 0644,
.proc_handler = &proc_do_uts_string,
.strategy = &sysctl_uts_string,
},
{
.ctl_name = KERN_DOMAINNAME,
.procname = "domainname",
.data = init_uts_ns.name.domainname,
.maxlen = sizeof(init_uts_ns.name.domainname),
.mode = 0644,
.proc_handler = &proc_do_uts_string,
.strategy = &sysctl_uts_string,
},
{
.ctl_name = KERN_PANIC,
.procname = "panic",
.data = &panic_timeout,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = KERN_CORE_USES_PID,
.procname = "core_uses_pid",
.data = &core_uses_pid,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = KERN_CORE_PATTERN,
.procname = "core_pattern",
.data = core_pattern,
.maxlen = 128,
.mode = 0644,
.proc_handler = &proc_dostring,
.strategy = &sysctl_string,
},
{
.ctl_name = KERN_TAINTED,
.procname = "tainted",
.data = &tainted,
.maxlen = sizeof(int),
.mode = 0444,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = KERN_CAP_BSET,
.procname = "cap-bound",
.data = &cap_bset,
.maxlen = sizeof(kernel_cap_t),
.mode = 0600,
.proc_handler = &proc_dointvec_bset,
},
#ifdef CONFIG_BLK_DEV_INITRD
{
.ctl_name = KERN_REALROOTDEV,
.procname = "real-root-dev",
.data = &real_root_dev,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#endif
#ifdef __sparc__
{
.ctl_name = KERN_SPARC_REBOOT,
.procname = "reboot-cmd",
.data = reboot_command,
.maxlen = 256,
.mode = 0644,
.proc_handler = &proc_dostring,
.strategy = &sysctl_string,
},
{
.ctl_name = KERN_SPARC_STOP_A,
.procname = "stop-a",
.data = &stop_a_enabled,
.maxlen = sizeof (int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = KERN_SPARC_SCONS_PWROFF,
.procname = "scons-poweroff",
.data = &scons_pwroff,
.maxlen = sizeof (int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#endif
#ifdef __hppa__
{
.ctl_name = KERN_HPPA_PWRSW,
.procname = "soft-power",
.data = &pwrsw_enabled,
.maxlen = sizeof (int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = KERN_HPPA_UNALIGNED,
.procname = "unaligned-trap",
.data = &unaligned_enabled,
.maxlen = sizeof (int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#endif
{
.ctl_name = KERN_CTLALTDEL,
.procname = "ctrl-alt-del",
.data = &C_A_D,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = KERN_PRINTK,
.procname = "printk",
.data = &console_loglevel,
.maxlen = 4*sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#ifdef CONFIG_KMOD
{
.ctl_name = KERN_MODPROBE,
.procname = "modprobe",
.data = &modprobe_path,
.maxlen = KMOD_PATH_LEN,
.mode = 0644,
.proc_handler = &proc_dostring,
.strategy = &sysctl_string,
},
#endif
#if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
{
.ctl_name = KERN_HOTPLUG,
.procname = "hotplug",
.data = &uevent_helper,
.maxlen = UEVENT_HELPER_PATH_LEN,
.mode = 0644,
.proc_handler = &proc_dostring,
.strategy = &sysctl_string,
},
#endif
#ifdef CONFIG_CHR_DEV_SG
{
.ctl_name = KERN_SG_BIG_BUFF,
.procname = "sg-big-buff",
.data = &sg_big_buff,
.maxlen = sizeof (int),
.mode = 0444,
.proc_handler = &proc_dointvec,
},
#endif
#ifdef CONFIG_BSD_PROCESS_ACCT
{
.ctl_name = KERN_ACCT,
.procname = "acct",
.data = &acct_parm,
.maxlen = 3*sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#endif
#ifdef CONFIG_SYSVIPC
{
.ctl_name = KERN_SHMMAX,
.procname = "shmmax",
.data = &init_ipc_ns.shm_ctlmax,
.maxlen = sizeof (init_ipc_ns.shm_ctlmax),
.mode = 0644,
.proc_handler = &proc_ipc_doulongvec_minmax,
.strategy = sysctl_ipc_data,
},
{
.ctl_name = KERN_SHMALL,
.procname = "shmall",
.data = &init_ipc_ns.shm_ctlall,
.maxlen = sizeof (init_ipc_ns.shm_ctlall),
.mode = 0644,
.proc_handler = &proc_ipc_doulongvec_minmax,
.strategy = sysctl_ipc_data,
},
{
.ctl_name = KERN_SHMMNI,
.procname = "shmmni",
.data = &init_ipc_ns.shm_ctlmni,
.maxlen = sizeof (init_ipc_ns.shm_ctlmni),
.mode = 0644,
.proc_handler = &proc_ipc_dointvec,
.strategy = sysctl_ipc_data,
},
{
.ctl_name = KERN_MSGMAX,
.procname = "msgmax",
.data = &init_ipc_ns.msg_ctlmax,
.maxlen = sizeof (init_ipc_ns.msg_ctlmax),
.mode = 0644,
.proc_handler = &proc_ipc_dointvec,
.strategy = sysctl_ipc_data,
},
{
.ctl_name = KERN_MSGMNI,
.procname = "msgmni",
.data = &init_ipc_ns.msg_ctlmni,
.maxlen = sizeof (init_ipc_ns.msg_ctlmni),
.mode = 0644,
.proc_handler = &proc_ipc_dointvec,
.strategy = sysctl_ipc_data,
},
{
.ctl_name = KERN_MSGMNB,
.procname = "msgmnb",
.data = &init_ipc_ns.msg_ctlmnb,
.maxlen = sizeof (init_ipc_ns.msg_ctlmnb),
.mode = 0644,
.proc_handler = &proc_ipc_dointvec,
.strategy = sysctl_ipc_data,
},
{
.ctl_name = KERN_SEM,
.procname = "sem",
.data = &init_ipc_ns.sem_ctls,
.maxlen = 4*sizeof (int),
.mode = 0644,
.proc_handler = &proc_ipc_dointvec,
.strategy = sysctl_ipc_data,
},
#endif
#ifdef CONFIG_MAGIC_SYSRQ
{
.ctl_name = KERN_SYSRQ,
.procname = "sysrq",
.data = &__sysrq_enabled,
.maxlen = sizeof (int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#endif
#ifdef CONFIG_PROC_SYSCTL
{
.ctl_name = KERN_CADPID,
.procname = "cad_pid",
.data = NULL,
.maxlen = sizeof (int),
.mode = 0600,
.proc_handler = &proc_do_cad_pid,
},
#endif
{
.ctl_name = KERN_MAX_THREADS,
.procname = "threads-max",
.data = &max_threads,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = KERN_RANDOM,
.procname = "random",
.mode = 0555,
.child = random_table,
},
#ifdef CONFIG_UNIX98_PTYS
{
.ctl_name = KERN_PTY,
.procname = "pty",
.mode = 0555,
.child = pty_table,
},
#endif
{
.ctl_name = KERN_OVERFLOWUID,
.procname = "overflowuid",
.data = &overflowuid,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec_minmax,
.strategy = &sysctl_intvec,
.extra1 = &minolduid,
.extra2 = &maxolduid,
},
{
.ctl_name = KERN_OVERFLOWGID,
.procname = "overflowgid",
.data = &overflowgid,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec_minmax,
.strategy = &sysctl_intvec,
.extra1 = &minolduid,
.extra2 = &maxolduid,
},
#ifdef CONFIG_S390
#ifdef CONFIG_MATHEMU
{
.ctl_name = KERN_IEEE_EMULATION_WARNINGS,
.procname = "ieee_emulation_warnings",
.data = &sysctl_ieee_emulation_warnings,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#endif
#ifdef CONFIG_NO_IDLE_HZ
{
.ctl_name = KERN_HZ_TIMER,
.procname = "hz_timer",
.data = &sysctl_hz_timer,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#endif
{
.ctl_name = KERN_S390_USER_DEBUG_LOGGING,
.procname = "userprocess_debug",
.data = &sysctl_userprocess_debug,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#endif
{
.ctl_name = KERN_PIDMAX,
.procname = "pid_max",
.data = &pid_max,
.maxlen = sizeof (int),
.mode = 0644,
.proc_handler = &proc_dointvec_minmax,
.strategy = sysctl_intvec,
.extra1 = &pid_max_min,
.extra2 = &pid_max_max,
},
{
.ctl_name = KERN_PANIC_ON_OOPS,
.procname = "panic_on_oops",
.data = &panic_on_oops,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = KERN_PRINTK_RATELIMIT,
.procname = "printk_ratelimit",
.data = &printk_ratelimit_jiffies,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec_jiffies,
.strategy = &sysctl_jiffies,
},
{
.ctl_name = KERN_PRINTK_RATELIMIT_BURST,
.procname = "printk_ratelimit_burst",
.data = &printk_ratelimit_burst,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = KERN_NGROUPS_MAX,
.procname = "ngroups_max",
.data = &ngroups_max,
.maxlen = sizeof (int),
.mode = 0444,
.proc_handler = &proc_dointvec,
},
#if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
{
.ctl_name = KERN_UNKNOWN_NMI_PANIC,
.procname = "unknown_nmi_panic",
.data = &unknown_nmi_panic,
.maxlen = sizeof (int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = KERN_NMI_WATCHDOG,
.procname = "nmi_watchdog",
.data = &nmi_watchdog_enabled,
.maxlen = sizeof (int),
.mode = 0644,
.proc_handler = &proc_nmi_enabled,
},
#endif
#if defined(CONFIG_X86)
{
.ctl_name = KERN_PANIC_ON_NMI,
.procname = "panic_on_unrecovered_nmi",
.data = &panic_on_unrecovered_nmi,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = KERN_BOOTLOADER_TYPE,
.procname = "bootloader_type",
.data = &bootloader_type,
.maxlen = sizeof (int),
.mode = 0444,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = CTL_UNNUMBERED,
.procname = "kstack_depth_to_print",
.data = &kstack_depth_to_print,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#endif
#if defined(CONFIG_MMU)
{
.ctl_name = KERN_RANDOMIZE,
.procname = "randomize_va_space",
.data = &randomize_va_space,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#endif
#if defined(CONFIG_S390) && defined(CONFIG_SMP)
{
.ctl_name = KERN_SPIN_RETRY,
.procname = "spin_retry",
.data = &spin_retry,
.maxlen = sizeof (int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#endif
#ifdef CONFIG_ACPI_SLEEP
{
.ctl_name = KERN_ACPI_VIDEO_FLAGS,
.procname = "acpi_video_flags",
.data = &acpi_video_flags,
.maxlen = sizeof (unsigned long),
.mode = 0644,
.proc_handler = &proc_doulongvec_minmax,
},
#endif
#ifdef CONFIG_IA64
{
.ctl_name = KERN_IA64_UNALIGNED,
.procname = "ignore-unaligned-usertrap",
.data = &no_unaligned_warning,
.maxlen = sizeof (int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#endif
#ifdef CONFIG_COMPAT
{
.ctl_name = KERN_COMPAT_LOG,
.procname = "compat-log",
.data = &compat_log,
.maxlen = sizeof (int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#endif
#ifdef CONFIG_RT_MUTEXES
{
.ctl_name = KERN_MAX_LOCK_DEPTH,
.procname = "max_lock_depth",
.data = &max_lock_depth,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#endif
{ .ctl_name = 0 }
};
/* Constants for minimum and maximum testing in vm_table.
We use these as one-element integer vectors. */
static int zero;
static int one_hundred = 100;
static ctl_table vm_table[] = {
{
.ctl_name = VM_OVERCOMMIT_MEMORY,
.procname = "overcommit_memory",
.data = &sysctl_overcommit_memory,
.maxlen = sizeof(sysctl_overcommit_memory),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = VM_PANIC_ON_OOM,
.procname = "panic_on_oom",
.data = &sysctl_panic_on_oom,
.maxlen = sizeof(sysctl_panic_on_oom),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = VM_OVERCOMMIT_RATIO,
.procname = "overcommit_ratio",
.data = &sysctl_overcommit_ratio,
.maxlen = sizeof(sysctl_overcommit_ratio),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = VM_PAGE_CLUSTER,
.procname = "page-cluster",
.data = &page_cluster,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = VM_DIRTY_BACKGROUND,
.procname = "dirty_background_ratio",
.data = &dirty_background_ratio,
.maxlen = sizeof(dirty_background_ratio),
.mode = 0644,
.proc_handler = &proc_dointvec_minmax,
.strategy = &sysctl_intvec,
.extra1 = &zero,
.extra2 = &one_hundred,
},
{
.ctl_name = VM_DIRTY_RATIO,
.procname = "dirty_ratio",
.data = &vm_dirty_ratio,
.maxlen = sizeof(vm_dirty_ratio),
.mode = 0644,
.proc_handler = &proc_dointvec_minmax,
.strategy = &sysctl_intvec,
.extra1 = &zero,
.extra2 = &one_hundred,
},
{
.ctl_name = VM_DIRTY_WB_CS,
.procname = "dirty_writeback_centisecs",
.data = &dirty_writeback_interval,
.maxlen = sizeof(dirty_writeback_interval),
.mode = 0644,
.proc_handler = &dirty_writeback_centisecs_handler,
},
{
.ctl_name = VM_DIRTY_EXPIRE_CS,
.procname = "dirty_expire_centisecs",
.data = &dirty_expire_interval,
.maxlen = sizeof(dirty_expire_interval),
.mode = 0644,
.proc_handler = &proc_dointvec_userhz_jiffies,
},
{
.ctl_name = VM_NR_PDFLUSH_THREADS,
.procname = "nr_pdflush_threads",
.data = &nr_pdflush_threads,
.maxlen = sizeof nr_pdflush_threads,
.mode = 0444 /* read-only*/,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = VM_SWAPPINESS,
.procname = "swappiness",
.data = &vm_swappiness,
.maxlen = sizeof(vm_swappiness),
.mode = 0644,
.proc_handler = &proc_dointvec_minmax,
.strategy = &sysctl_intvec,
.extra1 = &zero,
.extra2 = &one_hundred,
},
#ifdef CONFIG_HUGETLB_PAGE
{
.ctl_name = VM_HUGETLB_PAGES,
.procname = "nr_hugepages",
.data = &max_huge_pages,
.maxlen = sizeof(unsigned long),
.mode = 0644,
.proc_handler = &hugetlb_sysctl_handler,
.extra1 = (void *)&hugetlb_zero,
.extra2 = (void *)&hugetlb_infinity,
},
{
.ctl_name = VM_HUGETLB_GROUP,
.procname = "hugetlb_shm_group",
.data = &sysctl_hugetlb_shm_group,
.maxlen = sizeof(gid_t),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#endif
{
.ctl_name = VM_LOWMEM_RESERVE_RATIO,
.procname = "lowmem_reserve_ratio",
.data = &sysctl_lowmem_reserve_ratio,
.maxlen = sizeof(sysctl_lowmem_reserve_ratio),
.mode = 0644,
.proc_handler = &lowmem_reserve_ratio_sysctl_handler,
.strategy = &sysctl_intvec,
},
{
.ctl_name = VM_DROP_PAGECACHE,
.procname = "drop_caches",
.data = &sysctl_drop_caches,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = drop_caches_sysctl_handler,
.strategy = &sysctl_intvec,
},
{
.ctl_name = VM_MIN_FREE_KBYTES,
.procname = "min_free_kbytes",
.data = &min_free_kbytes,
.maxlen = sizeof(min_free_kbytes),
.mode = 0644,
.proc_handler = &min_free_kbytes_sysctl_handler,
.strategy = &sysctl_intvec,
.extra1 = &zero,
},
{
.ctl_name = VM_PERCPU_PAGELIST_FRACTION,
.procname = "percpu_pagelist_fraction",
.data = &percpu_pagelist_fraction,
.maxlen = sizeof(percpu_pagelist_fraction),
.mode = 0644,
.proc_handler = &percpu_pagelist_fraction_sysctl_handler,
.strategy = &sysctl_intvec,
.extra1 = &min_percpu_pagelist_fract,
},
#ifdef CONFIG_MMU
{
.ctl_name = VM_MAX_MAP_COUNT,
.procname = "max_map_count",
.data = &sysctl_max_map_count,
.maxlen = sizeof(sysctl_max_map_count),
.mode = 0644,
.proc_handler = &proc_dointvec
},
#endif
{
.ctl_name = VM_LAPTOP_MODE,
.procname = "laptop_mode",
.data = &laptop_mode,
.maxlen = sizeof(laptop_mode),
.mode = 0644,
.proc_handler = &proc_dointvec_jiffies,
.strategy = &sysctl_jiffies,
},
{
.ctl_name = VM_BLOCK_DUMP,
.procname = "block_dump",
.data = &block_dump,
.maxlen = sizeof(block_dump),
.mode = 0644,
.proc_handler = &proc_dointvec,
.strategy = &sysctl_intvec,
.extra1 = &zero,
},
{
.ctl_name = VM_VFS_CACHE_PRESSURE,
.procname = "vfs_cache_pressure",
.data = &sysctl_vfs_cache_pressure,
.maxlen = sizeof(sysctl_vfs_cache_pressure),
.mode = 0644,
.proc_handler = &proc_dointvec,
.strategy = &sysctl_intvec,
.extra1 = &zero,
},
#ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
{
.ctl_name = VM_LEGACY_VA_LAYOUT,
.procname = "legacy_va_layout",
.data = &sysctl_legacy_va_layout,
.maxlen = sizeof(sysctl_legacy_va_layout),
.mode = 0644,
.proc_handler = &proc_dointvec,
.strategy = &sysctl_intvec,
.extra1 = &zero,
},
#endif
#ifdef CONFIG_NUMA
{
.ctl_name = VM_ZONE_RECLAIM_MODE,
.procname = "zone_reclaim_mode",
.data = &zone_reclaim_mode,
.maxlen = sizeof(zone_reclaim_mode),
.mode = 0644,
.proc_handler = &proc_dointvec,
.strategy = &sysctl_intvec,
.extra1 = &zero,
},
{
.ctl_name = VM_MIN_UNMAPPED,
.procname = "min_unmapped_ratio",
.data = &sysctl_min_unmapped_ratio,
.maxlen = sizeof(sysctl_min_unmapped_ratio),
.mode = 0644,
.proc_handler = &sysctl_min_unmapped_ratio_sysctl_handler,
.strategy = &sysctl_intvec,
.extra1 = &zero,
.extra2 = &one_hundred,
},
{
.ctl_name = VM_MIN_SLAB,
.procname = "min_slab_ratio",
.data = &sysctl_min_slab_ratio,
.maxlen = sizeof(sysctl_min_slab_ratio),
.mode = 0644,
.proc_handler = &sysctl_min_slab_ratio_sysctl_handler,
.strategy = &sysctl_intvec,
.extra1 = &zero,
.extra2 = &one_hundred,
},
#endif
#ifdef CONFIG_X86_32
{
.ctl_name = VM_VDSO_ENABLED,
.procname = "vdso_enabled",
.data = &vdso_enabled,
.maxlen = sizeof(vdso_enabled),
.mode = 0644,
.proc_handler = &proc_dointvec,
.strategy = &sysctl_intvec,
.extra1 = &zero,
},
#endif
{ .ctl_name = 0 }
};
static ctl_table fs_table[] = {
{
.ctl_name = FS_NRINODE,
.procname = "inode-nr",
.data = &inodes_stat,
.maxlen = 2*sizeof(int),
.mode = 0444,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = FS_STATINODE,
.procname = "inode-state",
.data = &inodes_stat,
.maxlen = 7*sizeof(int),
.mode = 0444,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = FS_NRFILE,
.procname = "file-nr",
.data = &files_stat,
.maxlen = 3*sizeof(int),
.mode = 0444,
.proc_handler = &proc_nr_files,
},
{
.ctl_name = FS_MAXFILE,
.procname = "file-max",
.data = &files_stat.max_files,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = FS_DENTRY,
.procname = "dentry-state",
.data = &dentry_stat,
.maxlen = 6*sizeof(int),
.mode = 0444,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = FS_OVERFLOWUID,
.procname = "overflowuid",
.data = &fs_overflowuid,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec_minmax,
.strategy = &sysctl_intvec,
.extra1 = &minolduid,
.extra2 = &maxolduid,
},
{
.ctl_name = FS_OVERFLOWGID,
.procname = "overflowgid",
.data = &fs_overflowgid,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec_minmax,
.strategy = &sysctl_intvec,
.extra1 = &minolduid,
.extra2 = &maxolduid,
},
{
.ctl_name = FS_LEASES,
.procname = "leases-enable",
.data = &leases_enable,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#ifdef CONFIG_DNOTIFY
{
.ctl_name = FS_DIR_NOTIFY,
.procname = "dir-notify-enable",
.data = &dir_notify_enable,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#endif
#ifdef CONFIG_MMU
{
.ctl_name = FS_LEASE_TIME,
.procname = "lease-break-time",
.data = &lease_break_time,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = FS_AIO_NR,
.procname = "aio-nr",
.data = &aio_nr,
.maxlen = sizeof(aio_nr),
.mode = 0444,
.proc_handler = &proc_doulongvec_minmax,
},
{
.ctl_name = FS_AIO_MAX_NR,
.procname = "aio-max-nr",
.data = &aio_max_nr,
.maxlen = sizeof(aio_max_nr),
.mode = 0644,
.proc_handler = &proc_doulongvec_minmax,
},
#ifdef CONFIG_INOTIFY_USER
{
.ctl_name = FS_INOTIFY,
.procname = "inotify",
.mode = 0555,
.child = inotify_table,
},
#endif
#endif
{
.ctl_name = KERN_SETUID_DUMPABLE,
.procname = "suid_dumpable",
.data = &suid_dumpable,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{ .ctl_name = 0 }
};
static ctl_table debug_table[] = {
{ .ctl_name = 0 }
};
static ctl_table dev_table[] = {
{ .ctl_name = 0 }
};
extern void init_irq_proc (void);
static DEFINE_SPINLOCK(sysctl_lock);
/* called under sysctl_lock */
static int use_table(struct ctl_table_header *p)
{
if (unlikely(p->unregistering))
return 0;
p->used++;
return 1;
}
/* called under sysctl_lock */
static void unuse_table(struct ctl_table_header *p)
{
if (!--p->used)
if (unlikely(p->unregistering))
complete(p->unregistering);
}
/* called under sysctl_lock, will reacquire if has to wait */
static void start_unregistering(struct ctl_table_header *p)
{
/*
* if p->used is 0, nobody will ever touch that entry again;
* we'll eliminate all paths to it before dropping sysctl_lock
*/
if (unlikely(p->used)) {
struct completion wait;
init_completion(&wait);
p->unregistering = &wait;
spin_unlock(&sysctl_lock);
wait_for_completion(&wait);
spin_lock(&sysctl_lock);
}
/*
* do not remove from the list until nobody holds it; walking the
* list in do_sysctl() relies on that.
*/
list_del_init(&p->ctl_entry);
}
void __init sysctl_init(void)
{
#ifdef CONFIG_PROC_SYSCTL
register_proc_table(root_table, proc_sys_root, &root_table_header);
init_irq_proc();
#endif
}
#ifdef CONFIG_SYSCTL_SYSCALL
int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen)
{
struct list_head *tmp;
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;
}
spin_lock(&sysctl_lock);
tmp = &root_table_header.ctl_entry;
do {
struct ctl_table_header *head =
list_entry(tmp, struct ctl_table_header, ctl_entry);
if (!use_table(head))
continue;
spin_unlock(&sysctl_lock);
error = parse_table(name, nlen, oldval, oldlenp,
newval, newlen, head->ctl_table);
spin_lock(&sysctl_lock);
unuse_table(head);
if (error != -ENOTDIR)
break;
} while ((tmp = tmp->next) != &root_table_header.ctl_entry);
spin_unlock(&sysctl_lock);
return error;
}
asmlinkage long sys_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;
}
#endif /* CONFIG_SYSCTL_SYSCALL */
/*
* ctl_perm does NOT grant the superuser all rights automatically, because
* some sysctl variables are readonly even to root.
*/
static int test_perm(int mode, int op)
{
if (!current->euid)
mode >>= 6;
else if (in_egroup_p(0))
mode >>= 3;
if ((mode & op & 0007) == op)
return 0;
return -EACCES;
}
static inline int ctl_perm(ctl_table *table, int op)
{
int error;
error = security_sysctl(table, op);
if (error)
return error;
return test_perm(table->mode, op);
}
#ifdef CONFIG_SYSCTL_SYSCALL
static int parse_table(int __user *name, int nlen,
void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen,
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 || table->ctl_name == CTL_ANY) {
int error;
if (table->child) {
if (ctl_perm(table, 001))
return -EPERM;
if (table->strategy) {
error = table->strategy(
table, name, nlen,
oldval, oldlenp,
newval, newlen);
if (error)
return error;
}
name++;
nlen--;
table = table->child;
goto repeat;
}
error = do_sysctl_strategy(table, name, nlen,
oldval, oldlenp,
newval, newlen);
return error;
}
}
return -ENOTDIR;
}
/* Perform the actual read/write of a sysctl table entry. */
int do_sysctl_strategy (ctl_table *table,
int __user *name, int nlen,
void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen)
{
int op = 0, rc;
size_t len;
if (oldval)
op |= 004;
if (newval)
op |= 002;
if (ctl_perm(table, op))
return -EPERM;
if (table->strategy) {
rc = table->strategy(table, name, nlen, 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) {
if (oldval && oldlenp) {
if (get_user(len, oldlenp))
return -EFAULT;
if (len) {
if (len > table->maxlen)
len = table->maxlen;
if(copy_to_user(oldval, table->data, len))
return -EFAULT;
if(put_user(len, oldlenp))
return -EFAULT;
}
}
if (newval && newlen) {
len = newlen;
if (len > table->maxlen)
len = table->maxlen;
if(copy_from_user(table->data, newval, len))
return -EFAULT;
}
}
return 0;
}
#endif /* CONFIG_SYSCTL_SYSCALL */
/**
* register_sysctl_table - register a sysctl hierarchy
* @table: the top-level table structure
* @insert_at_head: whether the entry should be inserted in front or at the end
*
* Register a sysctl table hierarchy. @table should be a filled in ctl_table
* array. An entry with a ctl_name of 0 terminates the table.
*
* The members of the &ctl_table structure are used as follows:
*
* ctl_name - This is the numeric sysctl value used by sysctl(2). The number
* must be unique within that level of sysctl
*
* procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
* enter a sysctl file
*
* data - a pointer to data for use by proc_handler
*
* maxlen - the maximum size in bytes of the data
*
* mode - the file permissions for the /proc/sys file, and for sysctl(2)
*
* child - a pointer to the child sysctl table if this entry is a directory, or
* %NULL.
*
* proc_handler - the text handler routine (described below)
*
* strategy - the strategy routine (described below)
*
* de - for internal use by the sysctl routines
*
* extra1, extra2 - extra pointers usable by the proc handler routines
*
* Leaf nodes in the sysctl tree will be represented by a single file
* under /proc; non-leaf nodes will be represented by directories.
*
* sysctl(2) can automatically manage read and write requests through
* the sysctl table. The data and maxlen fields of the ctl_table
* struct enable minimal validation of the values being written to be
* performed, and the mode field allows minimal authentication.
*
* More sophisticated management can be enabled by the provision of a
* strategy routine with the table entry. This will be called before
* any automatic read or write of the data is performed.
*
* The strategy routine may return
*
* < 0 - Error occurred (error is passed to user process)
*
* 0 - OK - proceed with automatic read or write.
*
* > 0 - OK - read or write has been done by the strategy routine, so
* return immediately.
*
* There must be a proc_handler routine for any terminal nodes
* mirrored under /proc/sys (non-terminals are handled by a built-in
* directory handler). Several default handlers are available to
* cover common cases -
*
* proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
* proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
* proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
*
* It is the handler's job to read the input buffer from user memory
* and process it. The handler should return 0 on success.
*
* This routine returns %NULL on a failure to register, and a pointer
* to the table header on success.
*/
struct ctl_table_header *register_sysctl_table(ctl_table * table,
int insert_at_head)
{
struct ctl_table_header *tmp;
tmp = kmalloc(sizeof(struct ctl_table_header), GFP_KERNEL);
if (!tmp)
return NULL;
tmp->ctl_table = table;
INIT_LIST_HEAD(&tmp->ctl_entry);
tmp->used = 0;
tmp->unregistering = NULL;
spin_lock(&sysctl_lock);
if (insert_at_head)
list_add(&tmp->ctl_entry, &root_table_header.ctl_entry);
else
list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry);
spin_unlock(&sysctl_lock);
#ifdef CONFIG_PROC_SYSCTL
register_proc_table(table, proc_sys_root, tmp);
#endif
return tmp;
}
/**
* unregister_sysctl_table - unregister a sysctl table hierarchy
* @header: the header returned from register_sysctl_table
*
* Unregisters the sysctl table and all children. proc entries may not
* actually be removed until they are no longer used by anyone.
*/
void unregister_sysctl_table(struct ctl_table_header * header)
{
might_sleep();
spin_lock(&sysctl_lock);
start_unregistering(header);
#ifdef CONFIG_PROC_SYSCTL
unregister_proc_table(header->ctl_table, proc_sys_root);
#endif
spin_unlock(&sysctl_lock);
kfree(header);
}
#else /* !CONFIG_SYSCTL */
struct ctl_table_header * register_sysctl_table(ctl_table * table,
int insert_at_head)
{
return NULL;
}
void unregister_sysctl_table(struct ctl_table_header * table)
{
}
#endif /* CONFIG_SYSCTL */
/*
* /proc/sys support
*/
#ifdef CONFIG_PROC_SYSCTL
/* Scan the sysctl entries in table and add them all into /proc */
static void register_proc_table(ctl_table * table, struct proc_dir_entry *root, void *set)
{
struct proc_dir_entry *de;
int len;
mode_t mode;
for (; table->ctl_name || table->procname; table++) {
/* Can't do anything without a proc name. */
if (!table->procname)
continue;
/* Maybe we can't do anything with it... */
if (!table->proc_handler && !table->child) {
printk(KERN_WARNING "SYSCTL: Can't register %s\n",
table->procname);
continue;
}
len = strlen(table->procname);
mode = table->mode;
de = NULL;
if (table->proc_handler)
mode |= S_IFREG;
else {
mode |= S_IFDIR;
for (de = root->subdir; de; de = de->next) {
if (proc_match(len, table->procname, de))
break;
}
/* If the subdir exists already, de is non-NULL */
}
if (!de) {
de = create_proc_entry(table->procname, mode, root);
if (!de)
continue;
de->set = set;
de->data = (void *) table;
if (table->proc_handler)
de->proc_fops = &proc_sys_file_operations;
}
table->de = de;
if (de->mode & S_IFDIR)
register_proc_table(table->child, de, set);
}
}
/*
* Unregister a /proc sysctl table and any subdirectories.
*/
static void unregister_proc_table(ctl_table * table, struct proc_dir_entry *root)
{
struct proc_dir_entry *de;
for (; table->ctl_name || table->procname; table++) {
if (!(de = table->de))
continue;
if (de->mode & S_IFDIR) {
if (!table->child) {
printk (KERN_ALERT "Help - malformed sysctl tree on free\n");
continue;
}
unregister_proc_table(table->child, de);
/* Don't unregister directories which still have entries.. */
if (de->subdir)
continue;
}
/*
* In any case, mark the entry as goner; we'll keep it
* around if it's busy, but we'll know to do nothing with
* its fields. We are under sysctl_lock here.
*/
de->data = NULL;
/* Don't unregister proc entries that are still being used.. */
if (atomic_read(&de->count))
continue;
table->de = NULL;
remove_proc_entry(table->procname, root);
}
}
static ssize_t do_rw_proc(int write, struct file * file, char __user * buf,
size_t count, loff_t *ppos)
{
int op;
struct proc_dir_entry *de = PDE(file->f_path.dentry->d_inode);
struct ctl_table *table;
size_t res;
ssize_t error = -ENOTDIR;
spin_lock(&sysctl_lock);
if (de && de->data && use_table(de->set)) {
/*
* at that point we know that sysctl was not unregistered
* and won't be until we finish
*/
spin_unlock(&sysctl_lock);
table = (struct ctl_table *) de->data;
if (!table || !table->proc_handler)
goto out;
error = -EPERM;
op = (write ? 002 : 004);
if (ctl_perm(table, op))
goto out;
/* careful: calling conventions are nasty here */
res = count;
error = (*table->proc_handler)(table, write, file,
buf, &res, ppos);
if (!error)
error = res;
out:
spin_lock(&sysctl_lock);
unuse_table(de->set);
}
spin_unlock(&sysctl_lock);
return error;
}
static int proc_opensys(struct inode *inode, struct file *file)
{
if (file->f_mode & FMODE_WRITE) {
/*
* sysctl entries that are not writable,
* are _NOT_ writable, capabilities or not.
*/
if (!(inode->i_mode & S_IWUSR))
return -EPERM;
}
return 0;
}
static ssize_t proc_readsys(struct file * file, char __user * buf,
size_t count, loff_t *ppos)
{
return do_rw_proc(0, file, buf, count, ppos);
}
static ssize_t proc_writesys(struct file * file, const char __user * buf,
size_t count, loff_t *ppos)
{
return do_rw_proc(1, file, (char __user *) buf, count, ppos);
}
static int _proc_do_string(void* data, int maxlen, int write,
struct file *filp, void __user *buffer,
size_t *lenp, loff_t *ppos)
{
size_t len;
char __user *p;
char c;
if (!data || !maxlen || !*lenp ||
(*ppos && !write)) {
*lenp = 0;
return 0;
}
if (write) {
len = 0;
p = buffer;
while (len < *lenp) {
if (get_user(c, p++))
return -EFAULT;
if (c == 0 || c == '\n')
break;
len++;
}
if (len >= maxlen)
len = maxlen-1;
if(copy_from_user(data, buffer, len))
return -EFAULT;
((char *) data)[len] = 0;
*ppos += *lenp;
} else {
len = strlen(data);
if (len > maxlen)
len = maxlen;
if (len > *lenp)
len = *lenp;
if (len)
if(copy_to_user(buffer, data, len))
return -EFAULT;
if (len < *lenp) {
if(put_user('\n', ((char __user *) buffer) + len))
return -EFAULT;
len++;
}
*lenp = len;
*ppos += len;
}
return 0;
}
/**
* proc_dostring - read a string sysctl
* @table: the sysctl table
* @write: %TRUE if this is a write to the sysctl file
* @filp: the file structure
* @buffer: the user buffer
* @lenp: the size of the user buffer
* @ppos: file position
*
* Reads/writes a string from/to the user buffer. If the kernel
* buffer provided is not large enough to hold the string, the
* string is truncated. The copied string is %NULL-terminated.
* If the string is being read by the user process, it is copied
* and a newline '\n' is added. It is truncated if the buffer is
* not large enough.
*
* Returns 0 on success.
*/
int proc_dostring(ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return _proc_do_string(table->data, table->maxlen, write, filp,
buffer, lenp, ppos);
}
/*
* Special case of dostring for the UTS structure. This has locks
* to observe. Should this be in kernel/sys.c ????
*/
static int proc_do_uts_string(ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
int r;
void *which;
which = get_uts(table, write);
r = _proc_do_string(which, table->maxlen,write,filp,buffer,lenp, ppos);
put_uts(table, write, which);
return r;
}
static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
int *valp,
int write, void *data)
{
if (write) {
*valp = *negp ? -*lvalp : *lvalp;
} else {
int val = *valp;
if (val < 0) {
*negp = -1;
*lvalp = (unsigned long)-val;
} else {
*negp = 0;
*lvalp = (unsigned long)val;
}
}
return 0;
}
static int __do_proc_dointvec(void *tbl_data, ctl_table *table,
int write, struct file *filp, void __user *buffer,
size_t *lenp, loff_t *ppos,
int (*conv)(int *negp, unsigned long *lvalp, int *valp,
int write, void *data),
void *data)
{
#define TMPBUFLEN 21
int *i, vleft, first=1, neg, val;
unsigned long lval;
size_t left, len;
char buf[TMPBUFLEN], *p;
char __user *s = buffer;
if (!tbl_data || !table->maxlen || !*lenp ||
(*ppos && !write)) {
*lenp = 0;
return 0;
}
i = (int *) tbl_data;
vleft = table->maxlen / sizeof(*i);
left = *lenp;
if (!conv)
conv = do_proc_dointvec_conv;
for (; left && vleft--; i++, first=0) {
if (write) {
while (left) {
char c;
if (get_user(c, s))
return -EFAULT;
if (!isspace(c))
break;
left--;
s++;
}
if (!left)
break;
neg = 0;
len = left;
if (len > sizeof(buf) - 1)
len = sizeof(buf) - 1;
if (copy_from_user(buf, s, len))
return -EFAULT;
buf[len] = 0;
p = buf;
if (*p == '-' && left > 1) {
neg = 1;
p++;
}
if (*p < '0' || *p > '9')
break;
lval = simple_strtoul(p, &p, 0);
len = p-buf;
if ((len < left) && *p && !isspace(*p))
break;
if (neg)
val = -val;
s += len;
left -= len;
if (conv(&neg, &lval, i, 1, data))
break;
} else {
p = buf;
if (!first)
*p++ = '\t';
if (conv(&neg, &lval, i, 0, data))
break;
sprintf(p, "%s%lu", neg ? "-" : "", lval);
len = strlen(buf);
if (len > left)
len = left;
if(copy_to_user(s, buf, len))
return -EFAULT;
left -= len;
s += len;
}
}
if (!write && !first && left) {
if(put_user('\n', s))
return -EFAULT;
left--, s++;
}
if (write) {
while (left) {
char c;
if (get_user(c, s++))
return -EFAULT;
if (!isspace(c))
break;
left--;
}
}
if (write && first)
return -EINVAL;
*lenp -= left;
*ppos += *lenp;
return 0;
#undef TMPBUFLEN
}
static int do_proc_dointvec(ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos,
int (*conv)(int *negp, unsigned long *lvalp, int *valp,
int write, void *data),
void *data)
{
return __do_proc_dointvec(table->data, table, write, filp,
buffer, lenp, ppos, conv, data);
}
/**
* proc_dointvec - read a vector of integers
* @table: the sysctl table
* @write: %TRUE if this is a write to the sysctl file
* @filp: the file structure
* @buffer: the user buffer
* @lenp: the size of the user buffer
* @ppos: file position
*
* Reads/writes up to table->maxlen/sizeof(unsigned int) integer
* values from/to the user buffer, treated as an ASCII string.
*
* Returns 0 on success.
*/
int proc_dointvec(ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
NULL,NULL);
}
#define OP_SET 0
#define OP_AND 1
static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp,
int *valp,
int write, void *data)
{
int op = *(int *)data;
if (write) {
int val = *negp ? -*lvalp : *lvalp;
switch(op) {
case OP_SET: *valp = val; break;
case OP_AND: *valp &= val; break;
}
} else {
int val = *valp;
if (val < 0) {
*negp = -1;
*lvalp = (unsigned long)-val;
} else {
*negp = 0;
*lvalp = (unsigned long)val;
}
}
return 0;
}
/*
* init may raise the set.
*/
int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
int op;
if (!capable(CAP_SYS_MODULE)) {
return -EPERM;
}
op = is_init(current) ? OP_SET : OP_AND;
return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
do_proc_dointvec_bset_conv,&op);
}
struct do_proc_dointvec_minmax_conv_param {
int *min;
int *max;
};
static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
int *valp,
int write, void *data)
{
struct do_proc_dointvec_minmax_conv_param *param = data;
if (write) {
int val = *negp ? -*lvalp : *lvalp;
if ((param->min && *param->min > val) ||
(param->max && *param->max < val))
return -EINVAL;
*valp = val;
} else {
int val = *valp;
if (val < 0) {
*negp = -1;
*lvalp = (unsigned long)-val;
} else {
*negp = 0;
*lvalp = (unsigned long)val;
}
}
return 0;
}
/**
* proc_dointvec_minmax - read a vector of integers with min/max values
* @table: the sysctl table
* @write: %TRUE if this is a write to the sysctl file
* @filp: the file structure
* @buffer: the user buffer
* @lenp: the size of the user buffer
* @ppos: file position
*
* Reads/writes up to table->maxlen/sizeof(unsigned int) integer
* values from/to the user buffer, treated as an ASCII string.
*
* This routine will ensure the values are within the range specified by
* table->extra1 (min) and table->extra2 (max).
*
* Returns 0 on success.
*/
int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
struct do_proc_dointvec_minmax_conv_param param = {
.min = (int *) table->extra1,
.max = (int *) table->extra2,
};
return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
do_proc_dointvec_minmax_conv, &param);
}
static int __do_proc_doulongvec_minmax(void *data, ctl_table *table, int write,
struct file *filp,
void __user *buffer,
size_t *lenp, loff_t *ppos,
unsigned long convmul,
unsigned long convdiv)
{
#define TMPBUFLEN 21
unsigned long *i, *min, *max, val;
int vleft, first=1, neg;
size_t len, left;
char buf[TMPBUFLEN], *p;
char __user *s = buffer;
if (!data || !table->maxlen || !*lenp ||
(*ppos && !write)) {
*lenp = 0;
return 0;
}
i = (unsigned long *) data;
min = (unsigned long *) table->extra1;
max = (unsigned long *) table->extra2;
vleft = table->maxlen / sizeof(unsigned long);
left = *lenp;
for (; left && vleft--; i++, min++, max++, first=0) {
if (write) {
while (left) {
char c;
if (get_user(c, s))
return -EFAULT;
if (!isspace(c))
break;
left--;
s++;
}
if (!left)
break;
neg = 0;
len = left;
if (len > TMPBUFLEN-1)
len = TMPBUFLEN-1;
if (copy_from_user(buf, s, len))
return -EFAULT;
buf[len] = 0;
p = buf;
if (*p == '-' && left > 1) {
neg = 1;
p++;
}
if (*p < '0' || *p > '9')
break;
val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
len = p-buf;
if ((len < left) && *p && !isspace(*p))
break;
if (neg)
val = -val;
s += len;
left -= len;
if(neg)
continue;
if ((min && val < *min) || (max && val > *max))
continue;
*i = val;
} else {
p = buf;
if (!first)
*p++ = '\t';
sprintf(p, "%lu", convdiv * (*i) / convmul);
len = strlen(buf);
if (len > left)
len = left;
if(copy_to_user(s, buf, len))
return -EFAULT;
left -= len;
s += len;
}
}
if (!write && !first && left) {
if(put_user('\n', s))
return -EFAULT;
left--, s++;
}
if (write) {
while (left) {
char c;
if (get_user(c, s++))
return -EFAULT;
if (!isspace(c))
break;
left--;
}
}
if (write && first)
return -EINVAL;
*lenp -= left;
*ppos += *lenp;
return 0;
#undef TMPBUFLEN
}
static int do_proc_doulongvec_minmax(ctl_table *table, int write,
struct file *filp,
void __user *buffer,
size_t *lenp, loff_t *ppos,
unsigned long convmul,
unsigned long convdiv)
{
return __do_proc_doulongvec_minmax(table->data, table, write,
filp, buffer, lenp, ppos, convmul, convdiv);
}
/**
* proc_doulongvec_minmax - read a vector of long integers with min/max values
* @table: the sysctl table
* @write: %TRUE if this is a write to the sysctl file
* @filp: the file structure
* @buffer: the user buffer
* @lenp: the size of the user buffer
* @ppos: file position
*
* Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
* values from/to the user buffer, treated as an ASCII string.
*
* This routine will ensure the values are within the range specified by
* table->extra1 (min) and table->extra2 (max).
*
* Returns 0 on success.
*/
int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
}
/**
* proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
* @table: the sysctl table
* @write: %TRUE if this is a write to the sysctl file
* @filp: the file structure
* @buffer: the user buffer
* @lenp: the size of the user buffer
* @ppos: file position
*
* Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
* values from/to the user buffer, treated as an ASCII string. The values
* are treated as milliseconds, and converted to jiffies when they are stored.
*
* This routine will ensure the values are within the range specified by
* table->extra1 (min) and table->extra2 (max).
*
* Returns 0 on success.
*/
int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
struct file *filp,
void __user *buffer,
size_t *lenp, loff_t *ppos)
{
return do_proc_doulongvec_minmax(table, write, filp, buffer,
lenp, ppos, HZ, 1000l);
}
static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
int *valp,
int write, void *data)
{
if (write) {
if (*lvalp > LONG_MAX / HZ)
return 1;
*valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
} else {
int val = *valp;
unsigned long lval;
if (val < 0) {
*negp = -1;
lval = (unsigned long)-val;
} else {
*negp = 0;
lval = (unsigned long)val;
}
*lvalp = lval / HZ;
}
return 0;
}
static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
int *valp,
int write, void *data)
{
if (write) {
if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
return 1;
*valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
} else {
int val = *valp;
unsigned long lval;
if (val < 0) {
*negp = -1;
lval = (unsigned long)-val;
} else {
*negp = 0;
lval = (unsigned long)val;
}
*lvalp = jiffies_to_clock_t(lval);
}
return 0;
}
static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
int *valp,
int write, void *data)
{
if (write) {
*valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
} else {
int val = *valp;
unsigned long lval;
if (val < 0) {
*negp = -1;
lval = (unsigned long)-val;
} else {
*negp = 0;
lval = (unsigned long)val;
}
*lvalp = jiffies_to_msecs(lval);
}
return 0;
}
/**
* proc_dointvec_jiffies - read a vector of integers as seconds
* @table: the sysctl table
* @write: %TRUE if this is a write to the sysctl file
* @filp: the file structure
* @buffer: the user buffer
* @lenp: the size of the user buffer
* @ppos: file position
*
* Reads/writes up to table->maxlen/sizeof(unsigned int) integer
* values from/to the user buffer, treated as an ASCII string.
* The values read are assumed to be in seconds, and are converted into
* jiffies.
*
* Returns 0 on success.
*/
int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
do_proc_dointvec_jiffies_conv,NULL);
}
/**
* proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
* @table: the sysctl table
* @write: %TRUE if this is a write to the sysctl file
* @filp: the file structure
* @buffer: the user buffer
* @lenp: the size of the user buffer
* @ppos: pointer to the file position
*
* Reads/writes up to table->maxlen/sizeof(unsigned int) integer
* values from/to the user buffer, treated as an ASCII string.
* The values read are assumed to be in 1/USER_HZ seconds, and
* are converted into jiffies.
*
* Returns 0 on success.
*/
int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
do_proc_dointvec_userhz_jiffies_conv,NULL);
}
/**
* proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
* @table: the sysctl table
* @write: %TRUE if this is a write to the sysctl file
* @filp: the file structure
* @buffer: the user buffer
* @lenp: the size of the user buffer
* @ppos: file position
* @ppos: the current position in the file
*
* Reads/writes up to table->maxlen/sizeof(unsigned int) integer
* values from/to the user buffer, treated as an ASCII string.
* The values read are assumed to be in 1/1000 seconds, and
* are converted into jiffies.
*
* Returns 0 on success.
*/
int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
do_proc_dointvec_ms_jiffies_conv, NULL);
}
#ifdef CONFIG_SYSVIPC
static int proc_ipc_dointvec(ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
void *which;
which = get_ipc(table, write);
return __do_proc_dointvec(which, table, write, filp, buffer,
lenp, ppos, NULL, NULL);
}
static int proc_ipc_doulongvec_minmax(ctl_table *table, int write,
struct file *filp, void __user *buffer, size_t *lenp, loff_t *ppos)
{
void *which;
which = get_ipc(table, write);
return __do_proc_doulongvec_minmax(which, table, write, filp, buffer,
lenp, ppos, 1l, 1l);
}
#endif
static int proc_do_cad_pid(ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
struct pid *new_pid;
pid_t tmp;
int r;
tmp = pid_nr(cad_pid);
r = __do_proc_dointvec(&tmp, table, write, filp, buffer,
lenp, ppos, NULL, NULL);
if (r || !write)
return r;
new_pid = find_get_pid(tmp);
if (!new_pid)
return -ESRCH;
put_pid(xchg(&cad_pid, new_pid));
return 0;
}
#else /* CONFIG_PROC_FS */
int proc_dostring(ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return -ENOSYS;
}
static int proc_do_uts_string(ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return -ENOSYS;
}
#ifdef CONFIG_SYSVIPC
static int proc_do_ipc_string(ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return -ENOSYS;
}
static int proc_ipc_dointvec(ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return -ENOSYS;
}
static int proc_ipc_doulongvec_minmax(ctl_table *table, int write,
struct file *filp, void __user *buffer,
size_t *lenp, loff_t *ppos)
{
return -ENOSYS;
}
#endif
int proc_dointvec(ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return -ENOSYS;
}
int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return -ENOSYS;
}
int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return -ENOSYS;
}
int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return -ENOSYS;
}
int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return -ENOSYS;
}
int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return -ENOSYS;
}
int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return -ENOSYS;
}
int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
struct file *filp,
void __user *buffer,
size_t *lenp, loff_t *ppos)
{
return -ENOSYS;
}
#endif /* CONFIG_PROC_FS */
#ifdef CONFIG_SYSCTL_SYSCALL
/*
* General sysctl support routines
*/
/* The generic string strategy routine: */
int sysctl_string(ctl_table *table, int __user *name, int nlen,
void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen)
{
if (!table->data || !table->maxlen)
return -ENOTDIR;
if (oldval && oldlenp) {
size_t bufsize;
if (get_user(bufsize, oldlenp))
return -EFAULT;
if (bufsize) {
size_t len = strlen(table->data), copied;
/* This shouldn't trigger for a well-formed sysctl */
if (len > table->maxlen)
len = table->maxlen;
/* Copy up to a max of bufsize-1 bytes of the string */
copied = (len >= bufsize) ? bufsize - 1 : len;
if (copy_to_user(oldval, table->data, copied) ||
put_user(0, (char __user *)(oldval + copied)))
return -EFAULT;
if (put_user(len, oldlenp))
return -EFAULT;
}
}
if (newval && newlen) {
size_t len = newlen;
if (len > table->maxlen)
len = table->maxlen;
if(copy_from_user(table->data, newval, len))
return -EFAULT;
if (len == table->maxlen)
len--;
((char *) table->data)[len] = 0;
}
return 1;
}
/*
* This function makes sure that all of the integers in the vector
* are between the minimum and maximum values given in the arrays
* table->extra1 and table->extra2, respectively.
*/
int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen)
{
if (newval && newlen) {
int __user *vec = (int __user *) newval;
int *min = (int *) table->extra1;
int *max = (int *) table->extra2;
size_t length;
int i;
if (newlen % sizeof(int) != 0)
return -EINVAL;
if (!table->extra1 && !table->extra2)
return 0;
if (newlen > table->maxlen)
newlen = table->maxlen;
length = newlen / sizeof(int);
for (i = 0; i < length; i++) {
int value;
if (get_user(value, vec + i))
return -EFAULT;
if (min && value < min[i])
return -EINVAL;
if (max && value > max[i])
return -EINVAL;
}
}
return 0;
}
/* Strategy function to convert jiffies to seconds */
int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen)
{
if (oldval) {
size_t olen;
if (oldlenp) {
if (get_user(olen, oldlenp))
return -EFAULT;
if (olen!=sizeof(int))
return -EINVAL;
}
if (put_user(*(int *)(table->data)/HZ, (int __user *)oldval) ||
(oldlenp && put_user(sizeof(int),oldlenp)))
return -EFAULT;
}
if (newval && newlen) {
int new;
if (newlen != sizeof(int))
return -EINVAL;
if (get_user(new, (int __user *)newval))
return -EFAULT;
*(int *)(table->data) = new*HZ;
}
return 1;
}
/* Strategy function to convert jiffies to seconds */
int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen)
{
if (oldval) {
size_t olen;
if (oldlenp) {
if (get_user(olen, oldlenp))
return -EFAULT;
if (olen!=sizeof(int))
return -EINVAL;
}
if (put_user(jiffies_to_msecs(*(int *)(table->data)), (int __user *)oldval) ||
(oldlenp && put_user(sizeof(int),oldlenp)))
return -EFAULT;
}
if (newval && newlen) {
int new;
if (newlen != sizeof(int))
return -EINVAL;
if (get_user(new, (int __user *)newval))
return -EFAULT;
*(int *)(table->data) = msecs_to_jiffies(new);
}
return 1;
}
/* The generic string strategy routine: */
static int sysctl_uts_string(ctl_table *table, int __user *name, int nlen,
void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen)
{
struct ctl_table uts_table;
int r, write;
write = newval && newlen;
memcpy(&uts_table, table, sizeof(uts_table));
uts_table.data = get_uts(table, write);
r = sysctl_string(&uts_table, name, nlen,
oldval, oldlenp, newval, newlen);
put_uts(table, write, uts_table.data);
return r;
}
#ifdef CONFIG_SYSVIPC
/* The generic sysctl ipc data routine. */
static int sysctl_ipc_data(ctl_table *table, int __user *name, int nlen,
void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen)
{
size_t len;
void *data;
/* Get out of I don't have a variable */
if (!table->data || !table->maxlen)
return -ENOTDIR;
data = get_ipc(table, 1);
if (!data)
return -ENOTDIR;
if (oldval && oldlenp) {
if (get_user(len, oldlenp))
return -EFAULT;
if (len) {
if (len > table->maxlen)
len = table->maxlen;
if (copy_to_user(oldval, data, len))
return -EFAULT;
if (put_user(len, oldlenp))
return -EFAULT;
}
}
if (newval && newlen) {
if (newlen > table->maxlen)
newlen = table->maxlen;
if (copy_from_user(data, newval, newlen))
return -EFAULT;
}
return 1;
}
#endif
#else /* CONFIG_SYSCTL_SYSCALL */
asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
{
static int msg_count;
struct __sysctl_args tmp;
int name[CTL_MAXNAME];
int i;
/* Read in the sysctl name for better debug message logging */
if (copy_from_user(&tmp, args, sizeof(tmp)))
return -EFAULT;
if (tmp.nlen <= 0 || tmp.nlen >= CTL_MAXNAME)
return -ENOTDIR;
for (i = 0; i < tmp.nlen; i++)
if (get_user(name[<