sysctl.c 58.8 KB
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/*
 * 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>
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#include <linux/capability.h>
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#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>
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#include <linux/kobject.h>
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#include <linux/net.h>
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#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>
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#include <linux/nfs_fs.h>
#include <linux/acpi.h>
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#include <asm/uaccess.h>
#include <asm/processor.h>

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extern int proc_nr_files(ctl_table *table, int write, struct file *filp,
                     void __user *buffer, size_t *lenp, loff_t *ppos);

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#ifdef CONFIG_X86
#include <asm/nmi.h>
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#include <asm/stacktrace.h>
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#endif

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#if defined(CONFIG_SYSCTL)

/* External variables not in a header file. */
extern int C_A_D;
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extern int print_fatal_signals;
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extern int sysctl_overcommit_memory;
extern int sysctl_overcommit_ratio;
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extern int sysctl_panic_on_oom;
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extern int max_threads;
extern int core_uses_pid;
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extern int suid_dumpable;
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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;
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extern int sysctl_drop_caches;
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extern int percpu_pagelist_fraction;
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extern int compat_log;
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extern int maps_protect;
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extern int sysctl_stat_interval;
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/* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
static int maxolduid = 65535;
static int minolduid;
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static int min_percpu_pagelist_fract = 8;
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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 __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

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#ifdef CONFIG_S390
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#ifdef CONFIG_MATHEMU
extern int sysctl_ieee_emulation_warnings;
#endif
extern int sysctl_userprocess_debug;
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extern int spin_retry;
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#endif

extern int sysctl_hz_timer;

#ifdef CONFIG_BSD_PROCESS_ACCT
extern int acct_parm[];
#endif

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#ifdef CONFIG_IA64
extern int no_unaligned_warning;
#endif

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#ifdef CONFIG_RT_MUTEXES
extern int max_lock_depth;
#endif

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#ifdef CONFIG_SYSCTL_SYSCALL
static int parse_table(int __user *, int, void __user *, size_t __user *,
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		void __user *, size_t, ctl_table *);
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#endif

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#ifdef CONFIG_PROC_SYSCTL
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static int proc_do_cad_pid(ctl_table *table, int write, struct file *filp,
		  void __user *buffer, size_t *lenp, loff_t *ppos);
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static int proc_dointvec_taint(ctl_table *table, int write, struct file *filp,
			       void __user *buffer, size_t *lenp, loff_t *ppos);
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#endif
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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
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#ifdef CONFIG_INOTIFY_USER
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extern ctl_table inotify_table[];
#endif
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#ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
int sysctl_legacy_va_layout;
#endif

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/* 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,
	},
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/*
 * NOTE: do not add new entries to this table unless you have read
 * Documentation/sysctl/ctl_unnumbered.txt
 */
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	{ .ctl_name = 0 }
};

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#ifdef CONFIG_SCHED_DEBUG
static unsigned long min_sched_granularity_ns = 100000;		/* 100 usecs */
static unsigned long max_sched_granularity_ns = 1000000000;	/* 1 second */
static unsigned long min_wakeup_granularity_ns;			/* 0 usecs */
static unsigned long max_wakeup_granularity_ns = 1000000000;	/* 1 second */
#endif

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static ctl_table kern_table[] = {
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#ifdef CONFIG_SCHED_DEBUG
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "sched_granularity_ns",
		.data		= &sysctl_sched_granularity,
		.maxlen		= sizeof(unsigned int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec_minmax,
		.strategy	= &sysctl_intvec,
		.extra1		= &min_sched_granularity_ns,
		.extra2		= &max_sched_granularity_ns,
	},
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "sched_wakeup_granularity_ns",
		.data		= &sysctl_sched_wakeup_granularity,
		.maxlen		= sizeof(unsigned int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec_minmax,
		.strategy	= &sysctl_intvec,
		.extra1		= &min_wakeup_granularity_ns,
		.extra2		= &max_wakeup_granularity_ns,
	},
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "sched_batch_wakeup_granularity_ns",
		.data		= &sysctl_sched_batch_wakeup_granularity,
		.maxlen		= sizeof(unsigned int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec_minmax,
		.strategy	= &sysctl_intvec,
		.extra1		= &min_wakeup_granularity_ns,
		.extra2		= &max_wakeup_granularity_ns,
	},
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "sched_stat_granularity_ns",
		.data		= &sysctl_sched_stat_granularity,
		.maxlen		= sizeof(unsigned int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec_minmax,
		.strategy	= &sysctl_intvec,
		.extra1		= &min_wakeup_granularity_ns,
		.extra2		= &max_wakeup_granularity_ns,
	},
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "sched_runtime_limit_ns",
		.data		= &sysctl_sched_runtime_limit,
		.maxlen		= sizeof(unsigned int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec_minmax,
		.strategy	= &sysctl_intvec,
		.extra1		= &min_sched_granularity_ns,
		.extra2		= &max_sched_granularity_ns,
	},
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "sched_child_runs_first",
		.data		= &sysctl_sched_child_runs_first,
		.maxlen		= sizeof(unsigned int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "sched_features",
		.data		= &sysctl_sched_features,
		.maxlen		= sizeof(unsigned int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
#endif
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	{
		.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,
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		.maxlen		= CORENAME_MAX_SIZE,
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		.mode		= 0644,
		.proc_handler	= &proc_dostring,
		.strategy	= &sysctl_string,
	},
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#ifdef CONFIG_PROC_SYSCTL
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	{
		.ctl_name	= KERN_TAINTED,
		.procname	= "tainted",
		.data		= &tainted,
		.maxlen		= sizeof(int),
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		.mode		= 0644,
		.proc_handler	= &proc_dointvec_taint,
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	},
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#endif
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	{
		.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
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	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "print-fatal-signals",
		.data		= &print_fatal_signals,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
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#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
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#if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
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	{
		.ctl_name	= KERN_HOTPLUG,
		.procname	= "hotplug",
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		.data		= &uevent_helper,
		.maxlen		= UEVENT_HELPER_PATH_LEN,
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		.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_MAGIC_SYSRQ
	{
		.ctl_name	= KERN_SYSRQ,
		.procname	= "sysrq",
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		.data		= &__sysrq_enabled,
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		.maxlen		= sizeof (int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
#endif
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#ifdef CONFIG_PROC_SYSCTL
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	{
		.ctl_name	= KERN_CADPID,
		.procname	= "cad_pid",
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		.data		= NULL,
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		.maxlen		= sizeof (int),
		.mode		= 0600,
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		.proc_handler	= &proc_do_cad_pid,
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	},
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#endif
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	{
		.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,
	},
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#ifdef CONFIG_S390
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#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,
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		.proc_handler   = &proc_dointvec,
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	},
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	{
		.ctl_name       = KERN_NMI_WATCHDOG,
		.procname       = "nmi_watchdog",
		.data           = &nmi_watchdog_enabled,
		.maxlen         = sizeof (int),
		.mode           = 0644,
		.proc_handler   = &proc_nmi_enabled,
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	},
#endif
#if defined(CONFIG_X86)
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	{
		.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,
	},
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	{
		.ctl_name	= KERN_BOOTLOADER_TYPE,
		.procname	= "bootloader_type",
		.data		= &bootloader_type,
		.maxlen		= sizeof (int),
		.mode		= 0444,
		.proc_handler	= &proc_dointvec,
	},
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	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "kstack_depth_to_print",
		.data		= &kstack_depth_to_print,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
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#endif
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#if defined(CONFIG_MMU)
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	{
		.ctl_name	= KERN_RANDOMIZE,
		.procname	= "randomize_va_space",
		.data		= &randomize_va_space,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
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#endif
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#if defined(CONFIG_S390) && defined(CONFIG_SMP)
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	{
		.ctl_name	= KERN_SPIN_RETRY,
		.procname	= "spin_retry",
		.data		= &spin_retry,
		.maxlen		= sizeof (int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
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#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,
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		.proc_handler	= &proc_doulongvec_minmax,
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	},
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#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,
	},
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#endif
#ifdef CONFIG_COMPAT
	{
		.ctl_name	= KERN_COMPAT_LOG,
		.procname	= "compat-log",
		.data		= &compat_log,
		.maxlen		= sizeof (int),
	 	.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
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#endif
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#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
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#ifdef CONFIG_PROC_FS
	{
		.ctl_name       = CTL_UNNUMBERED,
		.procname       = "maps_protect",
		.data           = &maps_protect,
		.maxlen         = sizeof(int),
		.mode           = 0644,
		.proc_handler   = &proc_dointvec,
	},
#endif
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	{ .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,
	},
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	{
		.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,
	},
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	{
		.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",
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		.data		= &dirty_writeback_interval,
		.maxlen		= sizeof(dirty_writeback_interval),
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		.mode		= 0644,
		.proc_handler	= &dirty_writeback_centisecs_handler,
	},
	{
		.ctl_name	= VM_DIRTY_EXPIRE_CS,
		.procname	= "dirty_expire_centisecs",
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		.data		= &dirty_expire_interval,
		.maxlen		= sizeof(dirty_expire_interval),
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		.mode		= 0644,
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		.proc_handler	= &proc_dointvec_userhz_jiffies,
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	},
	{
		.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,
	 },
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	 {
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "hugepages_treat_as_movable",
		.data		= &hugepages_treat_as_movable,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= &hugetlb_treat_movable_handler,
	},
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#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,
	},
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	{
		.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,
	},
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	{
		.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,
	},
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	{
		.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,
	},
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#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,
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		.proc_handler	= &proc_dointvec_jiffies,
		.strategy	= &sysctl_jiffies,
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	},
	{
		.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
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#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,
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		.strategy	= &sysctl_intvec,
		.extra1		= &zero,
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	},
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	{
		.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,
	},
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	{
		.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,
	},
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#endif
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#ifdef CONFIG_SMP
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "stat_interval",
		.data		= &sysctl_stat_interval,
		.maxlen		= sizeof(sysctl_stat_interval),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec_jiffies,
		.strategy	= &sysctl_jiffies,
	},
#endif
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#ifdef CONFIG_SECURITY
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "mmap_min_addr",
		.data		= &mmap_min_addr,
		.maxlen         = sizeof(unsigned long),
		.mode		= 0644,
		.proc_handler	= &proc_doulongvec_minmax,
	},
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#ifdef CONFIG_NUMA
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "numa_zonelist_order",
		.data		= &numa_zonelist_order,
		.maxlen		= NUMA_ZONELIST_ORDER_LEN,
		.mode		= 0644,
		.proc_handler	= &numa_zonelist_order_handler,
		.strategy	= &sysctl_string,
	},
#endif
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#endif
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#if defined(CONFIG_X86_32) || \
   (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
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	{
		.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,
	},
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#endif
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/*
 * NOTE: do not add new entries to this table unless you have read
 * Documentation/sysctl/ctl_unnumbered.txt
 */
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	{ .ctl_name = 0 }
};

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#if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
static ctl_table binfmt_misc_table[] = {
	{ .ctl_name = 0 }
};
#endif

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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,
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		.proc_handler	= &proc_nr_files,
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	},
	{
		.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,
1115
		.proc_handler	= &proc_doulongvec_minmax,
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	},
	{
		.ctl_name	= FS_AIO_MAX_NR,
		.procname	= "aio-max-nr",
		.data		= &aio_max_nr,
		.maxlen		= sizeof(aio_max_nr),
		.mode		= 0644,
1123
		.proc_handler	= &proc_doulongvec_minmax,
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	},
1125
#ifdef CONFIG_INOTIFY_USER
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	{
		.ctl_name	= FS_INOTIFY,
		.procname	= "inotify",
		.mode		= 0555,
		.child		= inotify_table,
	},
#endif	
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#endif
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	{
		.ctl_name	= KERN_SETUID_DUMPABLE,
		.procname	= "suid_dumpable",
		.data		= &suid_dumpable,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
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#if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "binfmt_misc",
		.mode		= 0555,
		.child		= binfmt_misc_table,
	},
#endif
1150 1151 1152 1153
/*
 * NOTE: do not add new entries to this table unless you have read
 * Documentation/sysctl/ctl_unnumbered.txt
 */
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	{ .ctl_name = 0 }
};

static ctl_table debug_table[] = {
	{ .ctl_name = 0 }
};

static ctl_table dev_table[] = {
	{ .ctl_name = 0 }
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};
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1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205
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);
}

1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241
void sysctl_head_finish(struct ctl_table_header *head)
{
	if (!head)
		return;
	spin_lock(&sysctl_lock);
	unuse_table(head);
	spin_unlock(&sysctl_lock);
}

struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
{
	struct ctl_table_header *head;
	struct list_head *tmp;
	spin_lock(&sysctl_lock);
	if (prev) {
		tmp = &prev->ctl_entry;
		unuse_table(prev);
		goto next;
	}
	tmp = &root_table_header.ctl_entry;
	for (;;) {
		head = list_entry(tmp, struct ctl_table_header, ctl_entry);

		if (!use_table(head))
			goto next;
		spin_unlock(&sysctl_lock);
		return head;
	next:
		tmp = tmp->next;
		if (tmp == &root_table_header.ctl_entry)
			break;
	}
	spin_unlock(&sysctl_lock);
	return NULL;
}

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#ifdef CONFIG_SYSCTL_SYSCALL
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int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
	       void __user *newval, size_t newlen)
{
1246
	struct ctl_table_header *head;
1247
	int error = -ENOTDIR;
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	if (nlen <= 0 || nlen >= CTL_MAXNAME)
		return -ENOTDIR;
	if (oldval) {
		int old_len;
		if (!oldlenp || get_user(old_len, oldlenp))
			return -EFAULT;
	}
1256

1257 1258
	for (head = sysctl_head_next(NULL); head;
			head = sysctl_head_next(head)) {
1259
		error = parse_table(name, nlen, oldval, oldlenp, 
1260
					newval, newlen, head->ctl_table);
1261 1262
		if (error != -ENOTDIR) {
			sysctl_head_finish(head);
1263
			break;
1264 1265
		}
	}
1266
	return error;
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}

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;
}
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#endif /* CONFIG_SYSCTL_SYSCALL */
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/*
1286
 * sysctl_perm does NOT grant the superuser all rights automatically, because
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 * 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;
}

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int sysctl_perm(ctl_table *table, int op)
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{
	int error;
	error = security_sysctl(table, op);
	if (error)
		return error;
	return test_perm(table->mode, op);
}

1310
#ifdef CONFIG_SYSCTL_SYSCALL
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static int parse_table(int __user *name, int nlen,
		       void __user *oldval, size_t __user *oldlenp,
		       void __user *newval, size_t newlen,
1314
		       ctl_table *table)
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{
	int n;
repeat:
	if (!nlen)
		return -ENOTDIR;
	if (get_user(n, name))
		return -EFAULT;
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	for ( ; table->ctl_name || table->procname; table++) {
		if (!table->ctl_name)
			continue;
1325
		if (n == table->ctl_name) {
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			int error;
			if (table->child) {
1328
				if (sysctl_perm(table, 001))
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					return -EPERM;
				name++;
				nlen--;
				table = table->child;
				goto repeat;
			}
			error = do_sysctl_strategy(table, name, nlen,
						   oldval, oldlenp,
1337
						   newval, newlen);
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			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,
1348
			void __user *newval, size_t newlen)
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{
	int op = 0, rc;
	size_t len;

	if (oldval)
		op |= 004;
	if (newval) 
		op |= 002;
1357
	if (sysctl_perm(table, op))
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		return -EPERM;

	if (table->strategy) {
		rc = table->strategy(table, name, nlen, oldval, oldlenp,
1362
				     newval, newlen);
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		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;
}
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#endif /* CONFIG_SYSCTL_SYSCALL */
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static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
{
	for (; table->ctl_name || table->procname; table++) {
		table->parent = parent;
		if (table->child)
			sysctl_set_parent(table, table->child);
	}
}

static __init int sysctl_init(void)
{
	sysctl_set_parent(NULL, root_table);
	return 0;
}

core_initcall(sysctl_init);

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/**
 * register_sysctl_table - register a sysctl hierarchy
 * @table: the top-level table structure
 *
 * 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.
 */
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struct ctl_table_header *register_sysctl_table(ctl_table * table)
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{
	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);
1489 1490
	tmp->used = 0;
	tmp->unregistering = NULL;
1491
	sysctl_set_parent(NULL, table);
1492
	spin_lock(&sysctl_lock);
1493
	list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry);
1494
	spin_unlock(&sysctl_lock);
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	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)
{
1507 1508 1509 1510
	might_sleep();
	spin_lock(&sysctl_lock);
	start_unregistering(header);
	spin_unlock(&sysctl_lock);
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	kfree(header);
}

1514
#else /* !CONFIG_SYSCTL */
1515
struct ctl_table_header *register_sysctl_table(ctl_table * table)
1516 1517 1518 1519 1520 1521 1522 1523 1524 1525
{
	return NULL;
}

void unregister_sysctl_table(struct ctl_table_header * table)
{
}

#endif /* CONFIG_SYSCTL */

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/*
 * /proc/sys support
 */

1530
#ifdef CONFIG_PROC_SYSCTL
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static int _proc_do_string(void* data, int maxlen, int write,
			   struct file *filp, void __user *buffer,
			   size_t *lenp, loff_t *ppos)
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{
	size_t len;
	char __user *p;
	char c;
1539 1540

	if (!data || !maxlen || !*lenp) {
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		*lenp = 0;
		return 0;
	}
1544

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	if (write) {
		len = 0;
		p = buffer;
		while (len < *lenp) {
			if (get_user(c, p++))
				return -EFAULT;
			if (c == 0 || c == '\n')
				break;
			len++;
		}
1555 1556 1557
		if (len >= maxlen)
			len = maxlen-1;
		if(copy_from_user(data, buffer, len))
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			return -EFAULT;
1559
		((char *) data)[len] = 0;
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		*ppos += *lenp;
	} else {
1562 1563 1564
		len = strlen(data);
		if (len > maxlen)
			len = maxlen;
1565 1566 1567 1568 1569 1570 1571 1572 1573

		if (*ppos > len) {
			*lenp = 0;
			return 0;
		}

		data += *ppos;
		len  -= *ppos;

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		if (len > *lenp)
			len = *lenp;
		if (len)
1577
			if(copy_to_user(buffer, data, len))
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				return -EFAULT;
		if (len < *lenp) {
			if(put_user('\n', ((char __user *) buffer) + len))
				return -EFAULT;
			len++;
		}
		*lenp = len;
		*ppos += len;
	}
	return 0;
}

1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614
/**
 * 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);
}

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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;
}

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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,
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		  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;
	
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	if (!tbl_data || !table->maxlen || !*lenp ||
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	    (*ppos && !write)) {
		*lenp = 0;
		return 0;
	}
	
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	i = (int *) tbl_data;
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	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;
1686
				p++;
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			}
			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
}

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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);
}

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/**
 * 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
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#define OP_OR	2
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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;
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		case OP_OR:	*valp |= val; break;
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		}
	} 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;

1814
	if (write && !capable(CAP_SYS_MODULE)) {
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		return -EPERM;
	}

1818
	op = is_init(current) ? OP_SET : OP_AND;
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	return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
				do_proc_dointvec_bset_conv,&op);
}

1823 1824 1825 1826 1827 1828 1829 1830
/*
 *	Taint values can only be increased
 */
static int proc_dointvec_taint(ctl_table *table, int write, struct file *filp,
			       void __user *buffer, size_t *lenp, loff_t *ppos)
{
	int op;

1831
	if (write && !capable(CAP_SYS_ADMIN))
1832 1833 1834 1835 1836 1837 1838
		return -EPERM;

	op = OP_OR;
	return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
				do_proc_dointvec_bset_conv,&op);
}

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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);
}

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static int __do_proc_doulongvec_minmax(void *data, ctl_table *table, int write,
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				     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;
	
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	if (!data || !table->maxlen || !*lenp ||
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	    (*ppos && !write)) {
		*lenp = 0;
		return 0;
	}
	
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	i = (unsigned long *) data;
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	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;
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				p++;
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			}
			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
}

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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);
}

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/**
 * 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) {
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		if (*lvalp > LONG_MAX / HZ)
			return 1;
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		*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) {
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		if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
			return 1;
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		*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
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 * @ppos: pointer to the file position
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 *
 * 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
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 * @ppos: file position
 * @ppos: the current position in the file
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 *
 * 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);
}

2200 2201 2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220 2221
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;
}

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#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;
}

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 */


2284
#ifdef CONFIG_SYSCTL_SYSCALL
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/*
 * 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,
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		  void __user *newval, size_t newlen)
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{
	if (!table->data || !table->maxlen) 
		return -ENOTDIR;
	
	if (oldval && oldlenp) {
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		size_t bufsize;
		if (get_user(bufsize, oldlenp))
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			return -EFAULT;
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		if (bufsize) {
			size_t len = strlen(table->data), copied;

			/* This shouldn't trigger for a well-formed sysctl */
			if (len > table->maxlen)
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				len = table->maxlen;
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			/* 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)))
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				return -EFAULT;
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			if (put_user(len, oldlenp))
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				return -EFAULT;
		}
	}
	if (newval && newlen) {
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		size_t len = newlen;
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		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;
	}
2328
	return 1;
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}

/*
 * 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,
2338
		void __user *newval, size_t newlen)
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{

	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,
2374
		void __user *newval, size_t newlen)
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{
2376
	if (oldval && oldlenp) {
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		size_t olen;
2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389 2390

		if (get_user(olen, oldlenp))
			return -EFAULT;
		if (olen) {
			int val;

			if (olen < sizeof(int))
				return -EINVAL;

			val = *(int *)(table->data) / HZ;
			if (put_user(val, (int __user *)oldval))
				return -EFAULT;
			if (put_user(sizeof(int), oldlenp))
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				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,
2408
		void __user *newval, size_t newlen)
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{
2410
	if (oldval && oldlenp) {
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		size_t olen;
2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424

		if (get_user(olen, oldlenp))
			return -EFAULT;
		if (olen) {
			int val;

			if (olen < sizeof(int))
				return -EINVAL;

			val = jiffies_to_msecs(*(int *)(table->data));
			if (put_user(val, (int __user *)oldval))
				return -EFAULT;
			if (put_user(sizeof(int), oldlenp))
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				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;
}

2439 2440


2441
#else /* CONFIG_SYSCTL_SYSCALL */
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asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
{
2446
	static int msg_count;
2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462
	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[i], tmp.name + i))
			return -EFAULT;

	/* Ignore accesses to kernel.version */
	if ((tmp.nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
		goto out;
2463 2464 2465 2466 2467

	if (msg_count < 5) {
		msg_count++;
		printk(KERN_INFO
			"warning: process `%s' used the removed sysctl "
2468 2469 2470 2471
			"system call with ", current->comm);
		for (i = 0; i < tmp.nlen; i++)
			printk("%d.", name[i]);
		printk("\n");
2472
	}
2473
out:
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	return -ENOSYS;
}

int sysctl_string(ctl_table *table, int __user *name, int nlen,
		  void __user *oldval, size_t __user *oldlenp,
2479
		  void __user *newval, size_t newlen)
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{
	return -ENOSYS;
}

int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
		void __user *oldval, size_t __user *oldlenp,
2486
		void __user *newval, size_t newlen)
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{
	return -ENOSYS;
}

int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
		void __user *oldval, size_t __user *oldlenp,
2493
		void __user *newval, size_t newlen)
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{
	return -ENOSYS;
}

int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
		void __user *oldval, size_t __user *oldlenp,
2500
		void __user *newval, size_t newlen)
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{
	return -ENOSYS;
}

2505
#endif /* CONFIG_SYSCTL_SYSCALL */
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/*
 * No sense putting this after each symbol definition, twice,
 * exception granted :-)
 */
EXPORT_SYMBOL(proc_dointvec);
EXPORT_SYMBOL(proc_dointvec_jiffies);
EXPORT_SYMBOL(proc_dointvec_minmax);
EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
EXPORT_SYMBOL(proc_dostring);
EXPORT_SYMBOL(proc_doulongvec_minmax);
EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
EXPORT_SYMBOL(register_sysctl_table);
EXPORT_SYMBOL(sysctl_intvec);
EXPORT_SYMBOL(sysctl_jiffies);
EXPORT_SYMBOL(sysctl_ms_jiffies);
EXPORT_SYMBOL(sysctl_string);
EXPORT_SYMBOL(unregister_sysctl_table);