sysctl.c 76.1 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/security.h>
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#include <linux/ctype.h>
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#include <linux/kmemcheck.h>
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#include <linux/smp_lock.h>
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#include <linux/fs.h>
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#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>
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#include <linux/ratelimit.h>
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#include <linux/hugetlb.h>
#include <linux/initrd.h>
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#include <linux/key.h>
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#include <linux/times.h>
#include <linux/limits.h>
#include <linux/dcache.h>
#include <linux/syscalls.h>
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#include <linux/vmstat.h>
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#include <linux/nfs_fs.h>
#include <linux/acpi.h>
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#include <linux/reboot.h>
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#include <linux/ftrace.h>
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#include <linux/slow-work.h>
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#include <linux/perf_event.h>
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#include <asm/uaccess.h>
#include <asm/processor.h>

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

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static int deprecated_sysctl_warning(struct __sysctl_args *args);

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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 sysctl_oom_kill_allocating_task;
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extern int sysctl_oom_dump_tasks;
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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[];
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extern unsigned int core_pipe_limit;
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extern int pid_max;
extern int min_free_kbytes;
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 latencytop_enabled;
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extern int sysctl_nr_open_min, sysctl_nr_open_max;
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#ifndef CONFIG_MMU
extern int sysctl_nr_trim_pages;
#endif
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#ifdef CONFIG_RCU_TORTURE_TEST
extern int rcutorture_runnable;
#endif /* #ifdef CONFIG_RCU_TORTURE_TEST */
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#ifdef CONFIG_BLOCK
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extern int blk_iopoll_enabled;
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#endif
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/* Constants used for minimum and  maximum */
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#ifdef CONFIG_DETECT_SOFTLOCKUP
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static int sixty = 60;
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static int neg_one = -1;
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#endif

static int zero;
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static int __maybe_unused one = 1;
static int __maybe_unused two = 2;
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static unsigned long one_ul = 1;
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static int one_hundred = 100;
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#ifdef CONFIG_PRINTK
static int ten_thousand = 10000;
#endif
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/* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */
static unsigned long dirty_bytes_min = 2 * PAGE_SIZE;

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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;

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#ifdef CONFIG_MODULES
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extern char modprobe_path[];
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extern int modules_disabled;
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#endif
#ifdef CONFIG_CHR_DEV_SG
extern int sg_big_buff;
#endif

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#ifdef CONFIG_SPARC
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#include <asm/system.h>
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#endif

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#ifdef CONFIG_SPARC64
extern int sysctl_tsb_ratio;
#endif

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#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

#ifdef CONFIG_BSD_PROCESS_ACCT
extern int acct_parm[];
#endif

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#ifdef CONFIG_IA64
extern int no_unaligned_warning;
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extern int unaligned_dump_stack;
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#endif

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extern struct ratelimit_state printk_ratelimit_state;

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#ifdef CONFIG_RT_MUTEXES
extern int max_lock_depth;
#endif

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#ifdef CONFIG_PROC_SYSCTL
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static int proc_do_cad_pid(struct ctl_table *table, int write,
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		  void __user *buffer, size_t *lenp, loff_t *ppos);
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static int proc_taint(struct ctl_table *table, int write,
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			       void __user *buffer, size_t *lenp, loff_t *ppos);
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#endif
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static struct ctl_table root_table[];
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static struct ctl_table_root sysctl_table_root;
static struct ctl_table_header root_table_header = {
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	.count = 1,
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	.ctl_table = root_table,
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	.ctl_entry = LIST_HEAD_INIT(sysctl_table_root.default_set.list),
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	.root = &sysctl_table_root,
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	.set = &sysctl_table_root.default_set,
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};
static struct ctl_table_root sysctl_table_root = {
	.root_list = LIST_HEAD_INIT(sysctl_table_root.root_list),
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	.default_set.list = LIST_HEAD_INIT(root_table_header.ctl_entry),
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};
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static struct ctl_table kern_table[];
static struct ctl_table vm_table[];
static struct ctl_table fs_table[];
static struct ctl_table debug_table[];
static struct ctl_table dev_table[];
extern struct ctl_table random_table[];
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#ifdef CONFIG_INOTIFY_USER
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extern struct ctl_table inotify_table[];
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#endif
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#ifdef CONFIG_EPOLL
extern struct ctl_table epoll_table[];
#endif
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#ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
int sysctl_legacy_va_layout;
#endif

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extern int prove_locking;
extern int lock_stat;
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/* The default sysctl tables: */

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static struct ctl_table root_table[] = {
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	{
		.ctl_name	= CTL_KERN,
		.procname	= "kernel",
		.mode		= 0555,
		.child		= kern_table,
	},
	{
		.ctl_name	= CTL_VM,
		.procname	= "vm",
		.mode		= 0555,
		.child		= vm_table,
	},
	{
		.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
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static int min_sched_granularity_ns = 100000;		/* 100 usecs */
static int max_sched_granularity_ns = NSEC_PER_SEC;	/* 1 second */
static int min_wakeup_granularity_ns;			/* 0 usecs */
static int max_wakeup_granularity_ns = NSEC_PER_SEC;	/* 1 second */
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static int min_sched_tunable_scaling = SCHED_TUNABLESCALING_NONE;
static int max_sched_tunable_scaling = SCHED_TUNABLESCALING_END-1;
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#endif

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static struct ctl_table kern_table[] = {
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	{
		.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,
	},
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#ifdef CONFIG_SCHED_DEBUG
	{
		.ctl_name	= CTL_UNNUMBERED,
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		.procname	= "sched_min_granularity_ns",
		.data		= &sysctl_sched_min_granularity,
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		.maxlen		= sizeof(unsigned int),
		.mode		= 0644,
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		.proc_handler	= &sched_nr_latency_handler,
		.strategy	= &sysctl_intvec,
		.extra1		= &min_sched_granularity_ns,
		.extra2		= &max_sched_granularity_ns,
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	},
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	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "sched_latency_ns",
		.data		= &sysctl_sched_latency,
		.maxlen		= sizeof(unsigned int),
		.mode		= 0644,
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		.proc_handler	= &sched_nr_latency_handler,
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		.strategy	= &sysctl_intvec,
		.extra1		= &min_sched_granularity_ns,
		.extra2		= &max_sched_granularity_ns,
	},
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	{
		.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,
	},
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	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "sched_shares_ratelimit",
		.data		= &sysctl_sched_shares_ratelimit,
		.maxlen		= sizeof(unsigned int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
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	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "sched_tunable_scaling",
		.data		= &sysctl_sched_tunable_scaling,
		.maxlen		= sizeof(enum sched_tunable_scaling),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec_minmax,
		.strategy	= &sysctl_intvec,
		.extra1		= &min_sched_tunable_scaling,
		.extra2		= &max_sched_tunable_scaling,
	},

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	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "sched_shares_thresh",
		.data		= &sysctl_sched_shares_thresh,
		.maxlen		= sizeof(unsigned int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec_minmax,
		.strategy	= &sysctl_intvec,
		.extra1		= &zero,
	},
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	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "sched_migration_cost",
		.data		= &sysctl_sched_migration_cost,
		.maxlen		= sizeof(unsigned int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
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	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "sched_nr_migrate",
		.data		= &sysctl_sched_nr_migrate,
		.maxlen		= sizeof(unsigned int),
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		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
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	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "sched_time_avg",
		.data		= &sysctl_sched_time_avg,
		.maxlen		= sizeof(unsigned int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
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	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "timer_migration",
		.data		= &sysctl_timer_migration,
		.maxlen		= sizeof(unsigned int),
		.mode		= 0644,
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		.proc_handler	= &proc_dointvec_minmax,
		.strategy	= &sysctl_intvec,
		.extra1		= &zero,
		.extra2		= &one,
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	},
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#endif
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	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "sched_rt_period_us",
		.data		= &sysctl_sched_rt_period,
		.maxlen		= sizeof(unsigned int),
		.mode		= 0644,
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		.proc_handler	= &sched_rt_handler,
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	},
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "sched_rt_runtime_us",
		.data		= &sysctl_sched_rt_runtime,
		.maxlen		= sizeof(int),
		.mode		= 0644,
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		.proc_handler	= &sched_rt_handler,
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	},
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	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "sched_compat_yield",
		.data		= &sysctl_sched_compat_yield,
		.maxlen		= sizeof(unsigned int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
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#ifdef CONFIG_PROVE_LOCKING
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "prove_locking",
		.data		= &prove_locking,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
#endif
#ifdef CONFIG_LOCK_STAT
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "lock_stat",
		.data		= &lock_stat,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
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#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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	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "core_pipe_limit",
		.data		= &core_pipe_limit,
		.maxlen		= sizeof(unsigned int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
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#ifdef CONFIG_PROC_SYSCTL
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	{
		.procname	= "tainted",
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		.maxlen 	= sizeof(long),
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		.mode		= 0644,
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		.proc_handler	= &proc_taint,
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	},
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#endif
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#ifdef CONFIG_LATENCYTOP
	{
		.procname	= "latencytop",
		.data		= &latencytop_enabled,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
#endif
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#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 CONFIG_SPARC
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	{
		.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
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#ifdef CONFIG_SPARC64
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "tsb-ratio",
		.data		= &sysctl_tsb_ratio,
		.maxlen		= sizeof (int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
#endif
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#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,
	},
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#ifdef CONFIG_FUNCTION_TRACER
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	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "ftrace_enabled",
		.data		= &ftrace_enabled,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= &ftrace_enable_sysctl,
	},
#endif
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#ifdef CONFIG_STACK_TRACER
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "stack_tracer_enabled",
		.data		= &stack_tracer_enabled,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= &stack_trace_sysctl,
	},
#endif
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#ifdef CONFIG_TRACING
	{
		.ctl_name	= CTL_UNNUMBERED,
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		.procname	= "ftrace_dump_on_oops",
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		.data		= &ftrace_dump_on_oops,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
#endif
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#ifdef CONFIG_MODULES
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	{
		.ctl_name	= KERN_MODPROBE,
		.procname	= "modprobe",
		.data		= &modprobe_path,
		.maxlen		= KMOD_PATH_LEN,
		.mode		= 0644,
		.proc_handler	= &proc_dostring,
		.strategy	= &sysctl_string,
	},
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	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "modules_disabled",
		.data		= &modules_disabled,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		/* only handle a transition from default "0" to "1" */
		.proc_handler	= &proc_dointvec_minmax,
		.extra1		= &one,
		.extra2		= &one,
	},
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#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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	{
		.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,
	},
	{
		.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_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
	{
		.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,
	},
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#if defined CONFIG_PRINTK
	{
		.ctl_name	= KERN_PRINTK,
		.procname	= "printk",
		.data		= &console_loglevel,
		.maxlen		= 4*sizeof(int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
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	{
		.ctl_name	= KERN_PRINTK_RATELIMIT,
		.procname	= "printk_ratelimit",
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		.data		= &printk_ratelimit_state.interval,
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		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec_jiffies,
		.strategy	= &sysctl_jiffies,
	},
	{
		.ctl_name	= KERN_PRINTK_RATELIMIT_BURST,
		.procname	= "printk_ratelimit_burst",
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		.data		= &printk_ratelimit_state.burst,
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		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
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	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "printk_delay",
		.data		= &printk_delay_msec,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec_minmax,
		.strategy	= &sysctl_intvec,
		.extra1		= &zero,
		.extra2		= &ten_thousand,
	},
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#endif
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	{
		.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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	{
		.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	= CTL_UNNUMBERED,
		.procname	= "panic_on_io_nmi",
		.data		= &panic_on_io_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	= "bootloader_version",
		.data		= &bootloader_version,
		.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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	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "io_delay_type",
		.data		= &io_delay_type,
		.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
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#if	defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
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	{
		.procname	= "acpi_video_flags",
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		.data		= &acpi_realmode_flags,
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		.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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	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "unaligned-dump-stack",
		.data		= &unaligned_dump_stack,
		.maxlen		= sizeof (int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
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#endif
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#ifdef CONFIG_DETECT_SOFTLOCKUP
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	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "softlockup_panic",
		.data		= &softlockup_panic,
		.maxlen		= sizeof(int),
		.mode		= 0644,
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		.proc_handler	= &proc_dointvec_minmax,
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		.strategy	= &sysctl_intvec,
		.extra1		= &zero,
		.extra2		= &one,
	},
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	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "softlockup_thresh",
		.data		= &softlockup_thresh,
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		.maxlen		= sizeof(int),
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		.mode		= 0644,
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		.proc_handler	= &proc_dosoftlockup_thresh,
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		.strategy	= &sysctl_intvec,
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		.extra1		= &neg_one,
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		.extra2		= &sixty,
	},
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#endif
#ifdef CONFIG_DETECT_HUNG_TASK
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "hung_task_panic",
		.data		= &sysctl_hung_task_panic,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec_minmax,
		.strategy	= &sysctl_intvec,
		.extra1		= &zero,
		.extra2		= &one,
	},
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	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "hung_task_check_count",
		.data		= &sysctl_hung_task_check_count,
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		.maxlen		= sizeof(unsigned long),
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		.mode		= 0644,
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		.proc_handler	= &proc_doulongvec_minmax,
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		.strategy	= &sysctl_intvec,
	},
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "hung_task_timeout_secs",
		.data		= &sysctl_hung_task_timeout_secs,
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		.maxlen		= sizeof(unsigned long),
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		.mode		= 0644,
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		.proc_handler	= &proc_dohung_task_timeout_secs,
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		.strategy	= &sysctl_intvec,
	},
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "hung_task_warnings",
		.data		= &sysctl_hung_task_warnings,
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		.maxlen		= sizeof(unsigned long),
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		.mode		= 0644,
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		.proc_handler	= &proc_doulongvec_minmax,
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		.strategy	= &sysctl_intvec,
	},
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#endif
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#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,
	},
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#endif
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	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "poweroff_cmd",
		.data		= &poweroff_cmd,
		.maxlen		= POWEROFF_CMD_PATH_LEN,
		.mode		= 0644,
		.proc_handler	= &proc_dostring,
		.strategy	= &sysctl_string,
	},
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#ifdef CONFIG_KEYS
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "keys",
		.mode		= 0555,
		.child		= key_sysctls,
	},
#endif
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#ifdef CONFIG_RCU_TORTURE_TEST
	{
		.ctl_name       = CTL_UNNUMBERED,
		.procname       = "rcutorture_runnable",
		.data           = &rcutorture_runnable,
		.maxlen         = sizeof(int),
		.mode           = 0644,
		.proc_handler   = &proc_dointvec,
	},
#endif
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#ifdef CONFIG_SLOW_WORK
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "slow-work",
		.mode		= 0555,
		.child		= slow_work_sysctls,
	},
#endif
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#ifdef CONFIG_PERF_EVENTS
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	{
		.ctl_name	= CTL_UNNUMBERED,
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		.procname	= "perf_event_paranoid",
		.data		= &sysctl_perf_event_paranoid,
		.maxlen		= sizeof(sysctl_perf_event_paranoid),
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		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
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	{
		.ctl_name	= CTL_UNNUMBERED,
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		.procname	= "perf_event_mlock_kb",
		.data		= &sysctl_perf_event_mlock,
		.maxlen		= sizeof(sysctl_perf_event_mlock),
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		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
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	{
		.ctl_name	= CTL_UNNUMBERED,
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		.procname	= "perf_event_max_sample_rate",
		.data		= &sysctl_perf_event_sample_rate,
		.maxlen		= sizeof(sysctl_perf_event_sample_rate),
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		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
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#endif
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#ifdef CONFIG_KMEMCHECK
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "kmemcheck",
		.data		= &kmemcheck_enabled,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
#endif
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#ifdef CONFIG_BLOCK
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	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "blk_iopoll",
		.data		= &blk_iopoll_enabled,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
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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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static struct ctl_table vm_table[] = {
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	{
		.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	= CTL_UNNUMBERED,
		.procname	= "oom_kill_allocating_task",
		.data		= &sysctl_oom_kill_allocating_task,
		.maxlen		= sizeof(sysctl_oom_kill_allocating_task),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
1076 1077 1078 1079 1080 1081 1082 1083
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "oom_dump_tasks",
		.data		= &sysctl_oom_dump_tasks,
		.maxlen		= sizeof(sysctl_oom_dump_tasks),
		.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,
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		.proc_handler	= &dirty_background_ratio_handler,
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		.strategy	= &sysctl_intvec,
		.extra1		= &zero,
		.extra2		= &one_hundred,
	},
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	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "dirty_background_bytes",
		.data		= &dirty_background_bytes,
		.maxlen		= sizeof(dirty_background_bytes),
		.mode		= 0644,
		.proc_handler	= &dirty_background_bytes_handler,
		.strategy	= &sysctl_intvec,
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		.extra1		= &one_ul,
1120
	},
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	{
		.ctl_name	= VM_DIRTY_RATIO,
		.procname	= "dirty_ratio",
		.data		= &vm_dirty_ratio,
		.maxlen		= sizeof(vm_dirty_ratio),
		.mode		= 0644,
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		.proc_handler	= &dirty_ratio_handler,
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		.strategy	= &sysctl_intvec,
		.extra1		= &zero,
		.extra2		= &one_hundred,
	},
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	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "dirty_bytes",
		.data		= &vm_dirty_bytes,
		.maxlen		= sizeof(vm_dirty_bytes),
		.mode		= 0644,
		.proc_handler	= &dirty_bytes_handler,
		.strategy	= &sysctl_intvec,
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		.extra1		= &dirty_bytes_min,
1141
	},
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	{
		.procname	= "dirty_writeback_centisecs",
1144 1145
		.data		= &dirty_writeback_interval,
		.maxlen		= sizeof(dirty_writeback_interval),
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		.mode		= 0644,
		.proc_handler	= &dirty_writeback_centisecs_handler,
	},
	{
		.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,
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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
	 {
		.procname	= "nr_hugepages",
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		.data		= NULL,
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		.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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	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "nr_overcommit_hugepages",
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		.data		= NULL,
		.maxlen		= sizeof(unsigned long),
1206
		.mode		= 0644,
1207
		.proc_handler	= &hugetlb_overcommit_handler,
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		.extra1		= (void *)&hugetlb_zero,
		.extra2		= (void *)&hugetlb_infinity,
1210
	},
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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
	},
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#else
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "nr_trim_pages",
		.data		= &sysctl_nr_trim_pages,
		.maxlen		= sizeof(sysctl_nr_trim_pages),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec_minmax,
		.strategy	= &sysctl_intvec,
		.extra1		= &zero,
	},
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#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,
1322
	},
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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,
	},
1345
#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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	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "mmap_min_addr",
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		.data		= &dac_mmap_min_addr,
		.maxlen		= sizeof(unsigned long),
1362
		.mode		= 0644,
1363
		.proc_handler	= &mmap_min_addr_handler,
1364
	},
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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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#if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1377
   (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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#ifdef CONFIG_HIGHMEM
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "highmem_is_dirtyable",
		.data		= &vm_highmem_is_dirtyable,
		.maxlen		= sizeof(vm_highmem_is_dirtyable),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec_minmax,
		.strategy	= &sysctl_intvec,
		.extra1		= &zero,
		.extra2		= &one,
	},
#endif
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	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "scan_unevictable_pages",
		.data		= &scan_unevictable_pages,
		.maxlen		= sizeof(scan_unevictable_pages),
		.mode		= 0644,
		.proc_handler	= &scan_unevictable_handler,
	},
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#ifdef CONFIG_MEMORY_FAILURE
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "memory_failure_early_kill",
		.data		= &sysctl_memory_failure_early_kill,
		.maxlen		= sizeof(sysctl_memory_failure_early_kill),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec_minmax,
		.strategy	= &sysctl_intvec,
		.extra1		= &zero,
		.extra2		= &one,
	},
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "memory_failure_recovery",
		.data		= &sysctl_memory_failure_recovery,
		.maxlen		= sizeof(sysctl_memory_failure_recovery),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec_minmax,
		.strategy	= &sysctl_intvec,
		.extra1		= &zero,
		.extra2		= &one,
	},
#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)
1443
static struct ctl_table binfmt_misc_table[] = {
1444 1445 1446 1447
	{ .ctl_name = 0 }
};
#endif

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static struct ctl_table fs_table[] = {
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	{
		.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,
	},
	{
		.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,
	},
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	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "nr_open",
		.data		= &sysctl_nr_open,
		.maxlen		= sizeof(int),
		.mode		= 0644,
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		.proc_handler	= &proc_dointvec_minmax,
		.extra1		= &sysctl_nr_open_min,
		.extra2		= &sysctl_nr_open_max,
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	},
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	{
		.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,
	},
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#ifdef CONFIG_FILE_LOCKING
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	{
		.ctl_name	= FS_LEASES,
		.procname	= "leases-enable",
		.data		= &leases_enable,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
1529
#endif
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#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
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#ifdef CONFIG_FILE_LOCKING
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	{
		.ctl_name	= FS_LEASE_TIME,
		.procname	= "lease-break-time",
		.data		= &lease_break_time,
		.maxlen		= sizeof(int),
		.mode		= 0644,
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		.proc_handler	= &proc_dointvec,
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	},
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#endif
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#ifdef CONFIG_AIO
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	{
		.procname	= "aio-nr",
		.data		= &aio_nr,
		.maxlen		= sizeof(aio_nr),
		.mode		= 0444,
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		.proc_handler	= &proc_doulongvec_minmax,
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	},
	{
		.procname	= "aio-max-nr",
		.data		= &aio_max_nr,
		.maxlen		= sizeof(aio_max_nr),
		.mode		= 0644,
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		.proc_handler	= &proc_doulongvec_minmax,
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	},
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#endif /* CONFIG_AIO */
1567
#ifdef CONFIG_INOTIFY_USER
R
Robert Love 已提交
1568 1569 1570 1571 1572 1573 1574
	{
		.ctl_name	= FS_INOTIFY,
		.procname	= "inotify",
		.mode		= 0555,
		.child		= inotify_table,
	},
#endif	
1575 1576 1577 1578 1579 1580 1581
#ifdef CONFIG_EPOLL
	{
		.procname	= "epoll",
		.mode		= 0555,
		.child		= epoll_table,
	},
#endif
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Linus Torvalds 已提交
1582
#endif
A
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1583 1584 1585 1586 1587 1588
	{
		.ctl_name	= KERN_SETUID_DUMPABLE,
		.procname	= "suid_dumpable",
		.data		= &suid_dumpable,
		.maxlen		= sizeof(int),
		.mode		= 0644,
1589 1590 1591 1592
		.proc_handler	= &proc_dointvec_minmax,
		.strategy	= &sysctl_intvec,
		.extra1		= &zero,
		.extra2		= &two,
A
Alan Cox 已提交
1593
	},
1594 1595 1596 1597 1598 1599 1600 1601
#if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "binfmt_misc",
		.mode		= 0555,
		.child		= binfmt_misc_table,
	},
#endif
1602 1603 1604 1605
/*
 * NOTE: do not add new entries to this table unless you have read
 * Documentation/sysctl/ctl_unnumbered.txt
 */
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1606 1607 1608
	{ .ctl_name = 0 }
};

1609
static struct ctl_table debug_table[] = {
1610
#if defined(CONFIG_X86) || defined(CONFIG_PPC)
1611 1612 1613 1614 1615 1616 1617 1618 1619
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "exception-trace",
		.data		= &show_unhandled_signals,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= proc_dointvec
	},
#endif
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1620 1621 1622
	{ .ctl_name = 0 }
};

1623
static struct ctl_table dev_table[] = {
L
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1624
	{ .ctl_name = 0 }
R
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1625
};
L
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1626

1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659
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);
1660 1661 1662
	} else {
		/* anything non-NULL; we'll never dereference it */
		p->unregistering = ERR_PTR(-EINVAL);
1663 1664 1665 1666 1667 1668 1669 1670
	}
	/*
	 * 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);
}

1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696
void sysctl_head_get(struct ctl_table_header *head)
{
	spin_lock(&sysctl_lock);
	head->count++;
	spin_unlock(&sysctl_lock);
}

void sysctl_head_put(struct ctl_table_header *head)
{
	spin_lock(&sysctl_lock);
	if (!--head->count)
		kfree(head);
	spin_unlock(&sysctl_lock);
}

struct ctl_table_header *sysctl_head_grab(struct ctl_table_header *head)
{
	if (!head)
		BUG();
	spin_lock(&sysctl_lock);
	if (!use_table(head))
		head = ERR_PTR(-ENOENT);
	spin_unlock(&sysctl_lock);
	return head;
}

1697 1698 1699 1700 1701 1702 1703 1704 1705
void sysctl_head_finish(struct ctl_table_header *head)
{
	if (!head)
		return;
	spin_lock(&sysctl_lock);
	unuse_table(head);
	spin_unlock(&sysctl_lock);
}

1706 1707 1708 1709 1710 1711 1712 1713 1714
static struct ctl_table_set *
lookup_header_set(struct ctl_table_root *root, struct nsproxy *namespaces)
{
	struct ctl_table_set *set = &root->default_set;
	if (root->lookup)
		set = root->lookup(root, namespaces);
	return set;
}

1715 1716
static struct list_head *
lookup_header_list(struct ctl_table_root *root, struct nsproxy *namespaces)
1717
{
1718 1719
	struct ctl_table_set *set = lookup_header_set(root, namespaces);
	return &set->list;
1720 1721 1722 1723 1724 1725 1726
}

struct ctl_table_header *__sysctl_head_next(struct nsproxy *namespaces,
					    struct ctl_table_header *prev)
{
	struct ctl_table_root *root;
	struct list_head *header_list;
1727 1728
	struct ctl_table_header *head;
	struct list_head *tmp;
1729

1730 1731
	spin_lock(&sysctl_lock);
	if (prev) {
1732
		head = prev;
1733 1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745
		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:
1746
		root = head->root;
1747
		tmp = tmp->next;
1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759
		header_list = lookup_header_list(root, namespaces);
		if (tmp != header_list)
			continue;

		do {
			root = list_entry(root->root_list.next,
					struct ctl_table_root, root_list);
			if (root == &sysctl_table_root)
				goto out;
			header_list = lookup_header_list(root, namespaces);
		} while (list_empty(header_list));
		tmp = header_list->next;
1760
	}
1761
out:
1762 1763 1764 1765
	spin_unlock(&sysctl_lock);
	return NULL;
}

1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777
struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
{
	return __sysctl_head_next(current->nsproxy, prev);
}

void register_sysctl_root(struct ctl_table_root *root)
{
	spin_lock(&sysctl_lock);
	list_add_tail(&root->root_list, &sysctl_table_root.root_list);
	spin_unlock(&sysctl_lock);
}

1778
#ifdef CONFIG_SYSCTL_SYSCALL
1779
/* Perform the actual read/write of a sysctl table entry. */
1780 1781
static int do_sysctl_strategy(struct ctl_table_root *root,
			struct ctl_table *table,
1782 1783 1784 1785 1786 1787
			void __user *oldval, size_t __user *oldlenp,
			void __user *newval, size_t newlen)
{
	int op = 0, rc;

	if (oldval)
1788
		op |= MAY_READ;
1789
	if (newval)
1790
		op |= MAY_WRITE;
1791
	if (sysctl_perm(root, table, op))
1792 1793 1794
		return -EPERM;

	if (table->strategy) {
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		rc = table->strategy(table, oldval, oldlenp, newval, newlen);
1796 1797 1798 1799 1800 1801 1802 1803 1804
		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) {
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		rc = sysctl_data(table, oldval, oldlenp, newval, newlen);
1806 1807 1808 1809 1810 1811 1812 1813 1814
		if (rc < 0)
			return rc;
	}
	return 0;
}

static int parse_table(int __user *name, int nlen,
		       void __user *oldval, size_t __user *oldlenp,
		       void __user *newval, size_t newlen,
1815
		       struct ctl_table_root *root,
1816 1817 1818 1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 1829
		       struct ctl_table *table)
{
	int n;
repeat:
	if (!nlen)
		return -ENOTDIR;
	if (get_user(n, name))
		return -EFAULT;
	for ( ; table->ctl_name || table->procname; table++) {
		if (!table->ctl_name)
			continue;
		if (n == table->ctl_name) {
			int error;
			if (table->child) {
1830
				if (sysctl_perm(root, table, MAY_EXEC))
1831 1832 1833 1834 1835 1836
					return -EPERM;
				name++;
				nlen--;
				table = table->child;
				goto repeat;
			}
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			error = do_sysctl_strategy(root, table,
1838 1839 1840 1841 1842 1843 1844 1845
						   oldval, oldlenp,
						   newval, newlen);
			return error;
		}
	}
	return -ENOTDIR;
}

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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)
{
1849
	struct ctl_table_header *head;
1850
	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;
	}
1859

1860 1861
	for (head = sysctl_head_next(NULL); head;
			head = sysctl_head_next(head)) {
1862
		error = parse_table(name, nlen, oldval, oldlenp, 
1863 1864
					newval, newlen,
					head->root, head->ctl_table);
1865 1866
		if (error != -ENOTDIR) {
			sysctl_head_finish(head);
1867
			break;
1868 1869
		}
	}
1870
	return error;
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}

1873
SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
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{
	struct __sysctl_args tmp;
	int error;

	if (copy_from_user(&tmp, args, sizeof(tmp)))
		return -EFAULT;

1881 1882 1883 1884
	error = deprecated_sysctl_warning(&tmp);
	if (error)
		goto out;

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	lock_kernel();
	error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
			  tmp.newval, tmp.newlen);
	unlock_kernel();
1889
out:
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1890 1891
	return error;
}
1892
#endif /* CONFIG_SYSCTL_SYSCALL */
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1893 1894

/*
1895
 * 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)
{
1901
	if (!current_euid())
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		mode >>= 6;
	else if (in_egroup_p(0))
		mode >>= 3;
1905
	if ((op & ~mode & (MAY_READ|MAY_WRITE|MAY_EXEC)) == 0)
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		return 0;
	return -EACCES;
}

1910
int sysctl_perm(struct ctl_table_root *root, struct ctl_table *table, int op)
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{
	int error;
1913 1914
	int mode;

1915
	error = security_sysctl(table, op & (MAY_READ | MAY_WRITE | MAY_EXEC));
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	if (error)
		return error;
1918 1919 1920 1921 1922 1923 1924

	if (root->permissions)
		mode = root->permissions(root, current->nsproxy, table);
	else
		mode = table->mode;

	return test_perm(mode, op);
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}

1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938
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);
1939 1940 1941 1942 1943 1944
#ifdef CONFIG_SYSCTL_SYSCALL_CHECK
	{
		int err;
		err = sysctl_check_table(current->nsproxy, root_table);
	}
#endif
1945 1946 1947 1948 1949
	return 0;
}

core_initcall(sysctl_init);

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1950 1951
static struct ctl_table *is_branch_in(struct ctl_table *branch,
				      struct ctl_table *table)
1952 1953 1954 1955 1956 1957
{
	struct ctl_table *p;
	const char *s = branch->procname;

	/* branch should have named subdirectory as its first element */
	if (!s || !branch->child)
A
Al Viro 已提交
1958
		return NULL;
1959 1960 1961

	/* ... and nothing else */
	if (branch[1].procname || branch[1].ctl_name)
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1962
		return NULL;
1963 1964 1965 1966 1967 1968

	/* table should contain subdirectory with the same name */
	for (p = table; p->procname || p->ctl_name; p++) {
		if (!p->child)
			continue;
		if (p->procname && strcmp(p->procname, s) == 0)
A
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1969
			return p;
1970
	}
A
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1971
	return NULL;
1972 1973 1974 1975 1976 1977
}

/* see if attaching q to p would be an improvement */
static void try_attach(struct ctl_table_header *p, struct ctl_table_header *q)
{
	struct ctl_table *to = p->ctl_table, *by = q->ctl_table;
A
Al Viro 已提交
1978
	struct ctl_table *next;
1979 1980 1981
	int is_better = 0;
	int not_in_parent = !p->attached_by;

A
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1982
	while ((next = is_branch_in(by, to)) != NULL) {
1983 1984 1985 1986 1987
		if (by == q->attached_by)
			is_better = 1;
		if (to == p->attached_by)
			not_in_parent = 1;
		by = by->child;
A
Al Viro 已提交
1988
		to = next->child;
1989 1990 1991 1992 1993 1994 1995 1996 1997
	}

	if (is_better && not_in_parent) {
		q->attached_by = by;
		q->attached_to = to;
		q->parent = p;
	}
}

L
Linus Torvalds 已提交
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/**
1999 2000 2001
 * __register_sysctl_paths - register a sysctl hierarchy
 * @root: List of sysctl headers to register on
 * @namespaces: Data to compute which lists of sysctl entries are visible
2002
 * @path: The path to the directory the sysctl table is in.
L
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 * @table: the top-level table structure
 *
 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
2006
 * array. A completely 0 filled entry terminates the table.
L
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 *
2008
 * The members of the &struct ctl_table structure are used as follows:
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2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068
 *
 * 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.
 */
2069 2070 2071 2072
struct ctl_table_header *__register_sysctl_paths(
	struct ctl_table_root *root,
	struct nsproxy *namespaces,
	const struct ctl_path *path, struct ctl_table *table)
L
Linus Torvalds 已提交
2073
{
2074 2075 2076
	struct ctl_table_header *header;
	struct ctl_table *new, **prevp;
	unsigned int n, npath;
2077
	struct ctl_table_set *set;
2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093

	/* Count the path components */
	for (npath = 0; path[npath].ctl_name || path[npath].procname; ++npath)
		;

	/*
	 * For each path component, allocate a 2-element ctl_table array.
	 * The first array element will be filled with the sysctl entry
	 * for this, the second will be the sentinel (ctl_name == 0).
	 *
	 * We allocate everything in one go so that we don't have to
	 * worry about freeing additional memory in unregister_sysctl_table.
	 */
	header = kzalloc(sizeof(struct ctl_table_header) +
			 (2 * npath * sizeof(struct ctl_table)), GFP_KERNEL);
	if (!header)
L
Linus Torvalds 已提交
2094
		return NULL;
2095 2096 2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107 2108 2109 2110 2111

	new = (struct ctl_table *) (header + 1);

	/* Now connect the dots */
	prevp = &header->ctl_table;
	for (n = 0; n < npath; ++n, ++path) {
		/* Copy the procname */
		new->procname = path->procname;
		new->ctl_name = path->ctl_name;
		new->mode     = 0555;

		*prevp = new;
		prevp = &new->child;

		new += 2;
	}
	*prevp = table;
2112
	header->ctl_table_arg = table;
2113 2114 2115 2116

	INIT_LIST_HEAD(&header->ctl_entry);
	header->used = 0;
	header->unregistering = NULL;
2117
	header->root = root;
2118
	sysctl_set_parent(NULL, header->ctl_table);
2119
	header->count = 1;
2120
#ifdef CONFIG_SYSCTL_SYSCALL_CHECK
2121
	if (sysctl_check_table(namespaces, header->ctl_table)) {
2122
		kfree(header);
2123 2124
		return NULL;
	}
2125
#endif
2126
	spin_lock(&sysctl_lock);
2127
	header->set = lookup_header_set(root, namespaces);
2128 2129 2130 2131 2132 2133 2134 2135 2136 2137 2138 2139
	header->attached_by = header->ctl_table;
	header->attached_to = root_table;
	header->parent = &root_table_header;
	for (set = header->set; set; set = set->parent) {
		struct ctl_table_header *p;
		list_for_each_entry(p, &set->list, ctl_entry) {
			if (p->unregistering)
				continue;
			try_attach(p, header);
		}
	}
	header->parent->count++;
2140
	list_add_tail(&header->ctl_entry, &header->set->list);
2141
	spin_unlock(&sysctl_lock);
2142 2143 2144 2145

	return header;
}

2146 2147 2148 2149 2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 2161 2162
/**
 * register_sysctl_table_path - register a sysctl table hierarchy
 * @path: The path to the directory the sysctl table is in.
 * @table: the top-level table structure
 *
 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
 * array. A completely 0 filled entry terminates the table.
 *
 * See __register_sysctl_paths for more details.
 */
struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
						struct ctl_table *table)
{
	return __register_sysctl_paths(&sysctl_table_root, current->nsproxy,
					path, table);
}

2163 2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176
/**
 * register_sysctl_table - register a sysctl table hierarchy
 * @table: the top-level table structure
 *
 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
 * array. A completely 0 filled entry terminates the table.
 *
 * See register_sysctl_paths for more details.
 */
struct ctl_table_header *register_sysctl_table(struct ctl_table *table)
{
	static const struct ctl_path null_path[] = { {} };

	return register_sysctl_paths(null_path, table);
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Linus Torvalds 已提交
2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187
}

/**
 * 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)
{
2188
	might_sleep();
2189 2190 2191 2192

	if (header == NULL)
		return;

2193 2194
	spin_lock(&sysctl_lock);
	start_unregistering(header);
2195 2196 2197 2198
	if (!--header->parent->count) {
		WARN_ON(1);
		kfree(header->parent);
	}
2199 2200
	if (!--header->count)
		kfree(header);
2201
	spin_unlock(&sysctl_lock);
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Linus Torvalds 已提交
2202 2203
}

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2204 2205 2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218
int sysctl_is_seen(struct ctl_table_header *p)
{
	struct ctl_table_set *set = p->set;
	int res;
	spin_lock(&sysctl_lock);
	if (p->unregistering)
		res = 0;
	else if (!set->is_seen)
		res = 1;
	else
		res = set->is_seen(set);
	spin_unlock(&sysctl_lock);
	return res;
}

2219 2220 2221 2222 2223 2224 2225 2226 2227
void setup_sysctl_set(struct ctl_table_set *p,
	struct ctl_table_set *parent,
	int (*is_seen)(struct ctl_table_set *))
{
	INIT_LIST_HEAD(&p->list);
	p->parent = parent ? parent : &sysctl_table_root.default_set;
	p->is_seen = is_seen;
}

2228
#else /* !CONFIG_SYSCTL */
2229
struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
2230 2231 2232 2233
{
	return NULL;
}

2234 2235 2236 2237 2238 2239
struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
						    struct ctl_table *table)
{
	return NULL;
}

2240 2241 2242 2243
void unregister_sysctl_table(struct ctl_table_header * table)
{
}

2244 2245 2246 2247 2248 2249
void setup_sysctl_set(struct ctl_table_set *p,
	struct ctl_table_set *parent,
	int (*is_seen)(struct ctl_table_set *))
{
}

2250 2251 2252 2253
void sysctl_head_put(struct ctl_table_header *head)
{
}

2254 2255
#endif /* CONFIG_SYSCTL */

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/*
 * /proc/sys support
 */

2260
#ifdef CONFIG_PROC_SYSCTL
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2262
static int _proc_do_string(void* data, int maxlen, int write,
2263
			   void __user *buffer,
2264
			   size_t *lenp, loff_t *ppos)
L
Linus Torvalds 已提交
2265 2266 2267 2268
{
	size_t len;
	char __user *p;
	char c;
2269 2270

	if (!data || !maxlen || !*lenp) {
L
Linus Torvalds 已提交
2271 2272 2273
		*lenp = 0;
		return 0;
	}
2274

L
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2275 2276 2277 2278 2279 2280 2281 2282 2283 2284
	if (write) {
		len = 0;
		p = buffer;
		while (len < *lenp) {
			if (get_user(c, p++))
				return -EFAULT;
			if (c == 0 || c == '\n')
				break;
			len++;
		}
2285 2286 2287
		if (len >= maxlen)
			len = maxlen-1;
		if(copy_from_user(data, buffer, len))
L
Linus Torvalds 已提交
2288
			return -EFAULT;
2289
		((char *) data)[len] = 0;
L
Linus Torvalds 已提交
2290 2291
		*ppos += *lenp;
	} else {
2292 2293 2294
		len = strlen(data);
		if (len > maxlen)
			len = maxlen;
2295 2296 2297 2298 2299 2300 2301 2302 2303

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

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

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2304 2305 2306
		if (len > *lenp)
			len = *lenp;
		if (len)
2307
			if(copy_to_user(buffer, data, len))
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Linus Torvalds 已提交
2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 2319
				return -EFAULT;
		if (len < *lenp) {
			if(put_user('\n', ((char __user *) buffer) + len))
				return -EFAULT;
			len++;
		}
		*lenp = len;
		*ppos += len;
	}
	return 0;
}

2320 2321 2322 2323 2324 2325 2326 2327 2328 2329 2330 2331 2332 2333 2334 2335 2336
/**
 * proc_dostring - read a string sysctl
 * @table: the sysctl table
 * @write: %TRUE if this is a write to the sysctl file
 * @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.
 */
2337
int proc_dostring(struct ctl_table *table, int write,
2338 2339
		  void __user *buffer, size_t *lenp, loff_t *ppos)
{
2340
	return _proc_do_string(table->data, table->maxlen, write,
2341 2342 2343
			       buffer, lenp, ppos);
}

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2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363

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;
}

2364
static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
2365
		  int write, void __user *buffer,
K
Kirill Korotaev 已提交
2366
		  size_t *lenp, loff_t *ppos,
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2367 2368 2369 2370 2371
		  int (*conv)(int *negp, unsigned long *lvalp, int *valp,
			      int write, void *data),
		  void *data)
{
#define TMPBUFLEN 21
S
Sukanto Ghosh 已提交
2372
	int *i, vleft, first = 1, neg;
L
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2373 2374 2375 2376 2377 2378
	unsigned long lval;
	size_t left, len;
	
	char buf[TMPBUFLEN], *p;
	char __user *s = buffer;
	
K
Kirill Korotaev 已提交
2379
	if (!tbl_data || !table->maxlen || !*lenp ||
L
Linus Torvalds 已提交
2380 2381 2382 2383 2384
	    (*ppos && !write)) {
		*lenp = 0;
		return 0;
	}
	
K
Kirill Korotaev 已提交
2385
	i = (int *) tbl_data;
L
Linus Torvalds 已提交
2386 2387 2388 2389 2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400 2401 2402 2403 2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414
	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;
2415
				p++;
L
Linus Torvalds 已提交
2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436 2437 2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465 2466 2467 2468 2469 2470 2471
			}
			if (*p < '0' || *p > '9')
				break;

			lval = simple_strtoul(p, &p, 0);

			len = p-buf;
			if ((len < left) && *p && !isspace(*p))
				break;
			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
}

2472
static int do_proc_dointvec(struct ctl_table *table, int write,
K
Kirill Korotaev 已提交
2473 2474 2475 2476 2477
		  void __user *buffer, size_t *lenp, loff_t *ppos,
		  int (*conv)(int *negp, unsigned long *lvalp, int *valp,
			      int write, void *data),
		  void *data)
{
2478
	return __do_proc_dointvec(table->data, table, write,
K
Kirill Korotaev 已提交
2479 2480 2481
			buffer, lenp, ppos, conv, data);
}

L
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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
 * @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.
 */
2495
int proc_dointvec(struct ctl_table *table, int write,
L
Linus Torvalds 已提交
2496 2497
		     void __user *buffer, size_t *lenp, loff_t *ppos)
{
2498
    return do_proc_dointvec(table,write,buffer,lenp,ppos,
L
Linus Torvalds 已提交
2499 2500 2501
		    	    NULL,NULL);
}

2502
/*
A
Andi Kleen 已提交
2503 2504
 * Taint values can only be increased
 * This means we can safely use a temporary.
2505
 */
2506
static int proc_taint(struct ctl_table *table, int write,
2507 2508
			       void __user *buffer, size_t *lenp, loff_t *ppos)
{
A
Andi Kleen 已提交
2509 2510 2511
	struct ctl_table t;
	unsigned long tmptaint = get_taint();
	int err;
2512

2513
	if (write && !capable(CAP_SYS_ADMIN))
2514 2515
		return -EPERM;

A
Andi Kleen 已提交
2516 2517
	t = *table;
	t.data = &tmptaint;
2518
	err = proc_doulongvec_minmax(&t, write, buffer, lenp, ppos);
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Andi Kleen 已提交
2519 2520 2521 2522 2523 2524 2525 2526 2527 2528 2529 2530 2531 2532 2533 2534
	if (err < 0)
		return err;

	if (write) {
		/*
		 * Poor man's atomic or. Not worth adding a primitive
		 * to everyone's atomic.h for this
		 */
		int i;
		for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) {
			if ((tmptaint >> i) & 1)
				add_taint(i);
		}
	}

	return err;
2535 2536
}

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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
 * @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.
 */
2582
int proc_dointvec_minmax(struct ctl_table *table, int write,
L
Linus Torvalds 已提交
2583 2584 2585 2586 2587 2588
		  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,
	};
2589
	return do_proc_dointvec(table, write, buffer, lenp, ppos,
L
Linus Torvalds 已提交
2590 2591 2592
				do_proc_dointvec_minmax_conv, &param);
}

2593
static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
L
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2594 2595 2596 2597 2598 2599 2600 2601 2602 2603 2604 2605
				     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;
	
K
Kirill Korotaev 已提交
2606
	if (!data || !table->maxlen || !*lenp ||
L
Linus Torvalds 已提交
2607 2608 2609 2610 2611
	    (*ppos && !write)) {
		*lenp = 0;
		return 0;
	}
	
K
Kirill Korotaev 已提交
2612
	i = (unsigned long *) data;
L
Linus Torvalds 已提交
2613 2614 2615 2616 2617 2618 2619 2620 2621 2622 2623 2624 2625 2626 2627 2628 2629 2630 2631 2632 2633 2634 2635 2636 2637 2638 2639 2640
	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;
2641
				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
}

2697
static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
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Kirill Korotaev 已提交
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				     void __user *buffer,
				     size_t *lenp, loff_t *ppos,
				     unsigned long convmul,
				     unsigned long convdiv)
{
	return __do_proc_doulongvec_minmax(table->data, table, write,
2704
			buffer, lenp, ppos, convmul, convdiv);
K
Kirill Korotaev 已提交
2705 2706
}

L
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2707 2708 2709 2710 2711 2712 2713 2714 2715 2716 2717 2718 2719 2720 2721 2722
/**
 * 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
 * @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.
 */
2723
int proc_doulongvec_minmax(struct ctl_table *table, int write,
L
Linus Torvalds 已提交
2724 2725
			   void __user *buffer, size_t *lenp, loff_t *ppos)
{
2726
    return do_proc_doulongvec_minmax(table, write, buffer, lenp, ppos, 1l, 1l);
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}

/**
 * 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
 * @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.
 */
2746
int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
L
Linus Torvalds 已提交
2747 2748 2749
				      void __user *buffer,
				      size_t *lenp, loff_t *ppos)
{
2750
    return do_proc_doulongvec_minmax(table, write, buffer,
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				     lenp, ppos, HZ, 1000l);
}


static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
					 int *valp,
					 int write, void *data)
{
	if (write) {
2760 2761
		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) {
2783 2784
		if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
			return 1;
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Linus Torvalds 已提交
2785 2786 2787 2788 2789 2790 2791 2792 2793 2794 2795 2796 2797 2798 2799 2800 2801 2802 2803 2804 2805 2806 2807 2808 2809 2810 2811 2812 2813 2814 2815 2816 2817 2818 2819 2820 2821 2822 2823 2824 2825 2826 2827 2828 2829 2830 2831 2832 2833 2834 2835 2836
		*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
 * @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.
 */
2837
int proc_dointvec_jiffies(struct ctl_table *table, int write,
L
Linus Torvalds 已提交
2838 2839
			  void __user *buffer, size_t *lenp, loff_t *ppos)
{
2840
    return do_proc_dointvec(table,write,buffer,lenp,ppos,
L
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2841 2842 2843 2844 2845 2846 2847 2848 2849
		    	    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
 * @buffer: the user buffer
 * @lenp: the size of the user buffer
2850
 * @ppos: pointer to the file position
L
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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.
 */
2859
int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
L
Linus Torvalds 已提交
2860 2861
				 void __user *buffer, size_t *lenp, loff_t *ppos)
{
2862
    return do_proc_dointvec(table,write,buffer,lenp,ppos,
L
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2863 2864 2865 2866 2867 2868 2869 2870 2871
		    	    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
 * @buffer: the user buffer
 * @lenp: the size of the user buffer
2872 2873
 * @ppos: file position
 * @ppos: the current position in the file
L
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2874 2875 2876 2877 2878 2879 2880 2881
 *
 * 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.
 */
2882
int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
L
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2883 2884
			     void __user *buffer, size_t *lenp, loff_t *ppos)
{
2885
	return do_proc_dointvec(table, write, buffer, lenp, ppos,
L
Linus Torvalds 已提交
2886 2887 2888
				do_proc_dointvec_ms_jiffies_conv, NULL);
}

2889
static int proc_do_cad_pid(struct ctl_table *table, int write,
2890 2891 2892 2893 2894 2895
			   void __user *buffer, size_t *lenp, loff_t *ppos)
{
	struct pid *new_pid;
	pid_t tmp;
	int r;

2896
	tmp = pid_vnr(cad_pid);
2897

2898
	r = __do_proc_dointvec(&tmp, table, write, buffer,
2899 2900 2901 2902 2903 2904 2905 2906 2907 2908 2909 2910
			       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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2911 2912
#else /* CONFIG_PROC_FS */

2913
int proc_dostring(struct ctl_table *table, int write,
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2914 2915 2916 2917 2918
		  void __user *buffer, size_t *lenp, loff_t *ppos)
{
	return -ENOSYS;
}

2919
int proc_dointvec(struct ctl_table *table, int write,
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2920 2921 2922 2923 2924
		  void __user *buffer, size_t *lenp, loff_t *ppos)
{
	return -ENOSYS;
}

2925
int proc_dointvec_minmax(struct ctl_table *table, int write,
L
Linus Torvalds 已提交
2926 2927 2928 2929 2930
		    void __user *buffer, size_t *lenp, loff_t *ppos)
{
	return -ENOSYS;
}

2931
int proc_dointvec_jiffies(struct ctl_table *table, int write,
L
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2932 2933 2934 2935 2936
		    void __user *buffer, size_t *lenp, loff_t *ppos)
{
	return -ENOSYS;
}

2937
int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
L
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2938 2939 2940 2941 2942
		    void __user *buffer, size_t *lenp, loff_t *ppos)
{
	return -ENOSYS;
}

2943
int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
L
Linus Torvalds 已提交
2944 2945 2946 2947 2948
			     void __user *buffer, size_t *lenp, loff_t *ppos)
{
	return -ENOSYS;
}

2949
int proc_doulongvec_minmax(struct ctl_table *table, int write,
L
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2950 2951 2952 2953 2954
		    void __user *buffer, size_t *lenp, loff_t *ppos)
{
	return -ENOSYS;
}

2955
int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
L
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2956 2957 2958 2959 2960 2961 2962 2963 2964 2965
				      void __user *buffer,
				      size_t *lenp, loff_t *ppos)
{
    return -ENOSYS;
}


#endif /* CONFIG_PROC_FS */


2966
#ifdef CONFIG_SYSCTL_SYSCALL
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/*
 * General sysctl support routines 
 */

2971
/* The generic sysctl data routine (used if no strategy routine supplied) */
A
Alexey Dobriyan 已提交
2972
int sysctl_data(struct ctl_table *table,
2973 2974 2975 2976 2977 2978 2979 2980 2981 2982 2983 2984 2985 2986 2987 2988 2989 2990 2991 2992 2993 2994 2995 2996 2997 2998 2999 3000 3001 3002 3003 3004
		void __user *oldval, size_t __user *oldlenp,
		void __user *newval, size_t newlen)
{
	size_t len;

	/* Get out of I don't have a variable */
	if (!table->data || !table->maxlen)
		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, table->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(table->data, newval, newlen))
			return -EFAULT;
	}
	return 1;
}

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3005
/* The generic string strategy routine: */
A
Alexey Dobriyan 已提交
3006
int sysctl_string(struct ctl_table *table,
L
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3007
		  void __user *oldval, size_t __user *oldlenp,
3008
		  void __user *newval, size_t newlen)
L
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3009 3010 3011 3012 3013
{
	if (!table->data || !table->maxlen) 
		return -ENOTDIR;
	
	if (oldval && oldlenp) {
3014 3015
		size_t bufsize;
		if (get_user(bufsize, oldlenp))
L
Linus Torvalds 已提交
3016
			return -EFAULT;
3017 3018 3019 3020 3021
		if (bufsize) {
			size_t len = strlen(table->data), copied;

			/* This shouldn't trigger for a well-formed sysctl */
			if (len > table->maxlen)
L
Linus Torvalds 已提交
3022
				len = table->maxlen;
3023 3024 3025 3026 3027 3028

			/* 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)))
L
Linus Torvalds 已提交
3029
				return -EFAULT;
3030
			if (put_user(len, oldlenp))
L
Linus Torvalds 已提交
3031 3032 3033 3034
				return -EFAULT;
		}
	}
	if (newval && newlen) {
3035
		size_t len = newlen;
L
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3036 3037 3038 3039 3040 3041 3042 3043
		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;
	}
3044
	return 1;
L
Linus Torvalds 已提交
3045 3046 3047 3048 3049 3050 3051
}

/*
 * 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.
 */
A
Alexey Dobriyan 已提交
3052
int sysctl_intvec(struct ctl_table *table,
L
Linus Torvalds 已提交
3053
		void __user *oldval, size_t __user *oldlenp,
3054
		void __user *newval, size_t newlen)
L
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3055 3056 3057 3058 3059 3060 3061 3062 3063 3064 3065 3066 3067 3068 3069 3070 3071 3072 3073 3074 3075 3076 3077 3078 3079 3080 3081 3082 3083 3084 3085 3086 3087
{

	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 */ 
A
Alexey Dobriyan 已提交
3088
int sysctl_jiffies(struct ctl_table *table,
L
Linus Torvalds 已提交
3089
		void __user *oldval, size_t __user *oldlenp,
3090
		void __user *newval, size_t newlen)
L
Linus Torvalds 已提交
3091
{
3092
	if (oldval && oldlenp) {
L
Linus Torvalds 已提交
3093
		size_t olen;
3094 3095 3096 3097 3098 3099 3100 3101 3102 3103 3104 3105 3106

		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))
L
Linus Torvalds 已提交
3107 3108 3109 3110 3111 3112 3113 3114 3115 3116 3117 3118 3119 3120 3121
				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 */ 
A
Alexey Dobriyan 已提交
3122
int sysctl_ms_jiffies(struct ctl_table *table,
L
Linus Torvalds 已提交
3123
		void __user *oldval, size_t __user *oldlenp,
3124
		void __user *newval, size_t newlen)
L
Linus Torvalds 已提交
3125
{
3126
	if (oldval && oldlenp) {
L
Linus Torvalds 已提交
3127
		size_t olen;
3128 3129 3130 3131 3132 3133 3134 3135 3136 3137 3138 3139 3140

		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))
L
Linus Torvalds 已提交
3141 3142 3143 3144 3145 3146 3147 3148 3149 3150 3151 3152 3153 3154
				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;
}

3155 3156


3157
#else /* CONFIG_SYSCTL_SYSCALL */
L
Linus Torvalds 已提交
3158 3159


3160
SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
L
Linus Torvalds 已提交
3161
{
3162
	struct __sysctl_args tmp;
3163
	int error;
3164 3165 3166 3167

	if (copy_from_user(&tmp, args, sizeof(tmp)))
		return -EFAULT;

3168
	error = deprecated_sysctl_warning(&tmp);
3169

3170 3171 3172 3173 3174
	/* If no error reading the parameters then just -ENOSYS ... */
	if (!error)
		error = -ENOSYS;

	return error;
L
Linus Torvalds 已提交
3175 3176
}

A
Alexey Dobriyan 已提交
3177
int sysctl_data(struct ctl_table *table,
3178 3179 3180 3181 3182 3183
		  void __user *oldval, size_t __user *oldlenp,
		  void __user *newval, size_t newlen)
{
	return -ENOSYS;
}

A
Alexey Dobriyan 已提交
3184
int sysctl_string(struct ctl_table *table,
L
Linus Torvalds 已提交
3185
		  void __user *oldval, size_t __user *oldlenp,
3186
		  void __user *newval, size_t newlen)
L
Linus Torvalds 已提交
3187 3188 3189 3190
{
	return -ENOSYS;
}

A
Alexey Dobriyan 已提交
3191
int sysctl_intvec(struct ctl_table *table,
L
Linus Torvalds 已提交
3192
		void __user *oldval, size_t __user *oldlenp,
3193
		void __user *newval, size_t newlen)
L
Linus Torvalds 已提交
3194 3195 3196 3197
{
	return -ENOSYS;
}

A
Alexey Dobriyan 已提交
3198
int sysctl_jiffies(struct ctl_table *table,
L
Linus Torvalds 已提交
3199
		void __user *oldval, size_t __user *oldlenp,
3200
		void __user *newval, size_t newlen)
L
Linus Torvalds 已提交
3201 3202 3203 3204
{
	return -ENOSYS;
}

A
Alexey Dobriyan 已提交
3205
int sysctl_ms_jiffies(struct ctl_table *table,
L
Linus Torvalds 已提交
3206
		void __user *oldval, size_t __user *oldlenp,
3207
		void __user *newval, size_t newlen)
L
Linus Torvalds 已提交
3208 3209 3210 3211
{
	return -ENOSYS;
}

3212
#endif /* CONFIG_SYSCTL_SYSCALL */
L
Linus Torvalds 已提交
3213

3214 3215 3216 3217 3218 3219
static int deprecated_sysctl_warning(struct __sysctl_args *args)
{
	static int msg_count;
	int name[CTL_MAXNAME];
	int i;

3220 3221 3222 3223
	/* Check args->nlen. */
	if (args->nlen < 0 || args->nlen > CTL_MAXNAME)
		return -ENOTDIR;

3224 3225 3226 3227 3228 3229 3230 3231 3232 3233 3234 3235 3236 3237 3238 3239 3240 3241 3242 3243 3244
	/* Read in the sysctl name for better debug message logging */
	for (i = 0; i < args->nlen; i++)
		if (get_user(name[i], args->name + i))
			return -EFAULT;

	/* Ignore accesses to kernel.version */
	if ((args->nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
		return 0;

	if (msg_count < 5) {
		msg_count++;
		printk(KERN_INFO
			"warning: process `%s' used the deprecated sysctl "
			"system call with ", current->comm);
		for (i = 0; i < args->nlen; i++)
			printk("%d.", name[i]);
		printk("\n");
	}
	return 0;
}

L
Linus Torvalds 已提交
3245 3246 3247 3248 3249 3250 3251 3252 3253 3254 3255 3256 3257
/*
 * 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);
3258
EXPORT_SYMBOL(register_sysctl_paths);
L
Linus Torvalds 已提交
3259 3260 3261 3262
EXPORT_SYMBOL(sysctl_intvec);
EXPORT_SYMBOL(sysctl_jiffies);
EXPORT_SYMBOL(sysctl_ms_jiffies);
EXPORT_SYMBOL(sysctl_string);
3263
EXPORT_SYMBOL(sysctl_data);
L
Linus Torvalds 已提交
3264
EXPORT_SYMBOL(unregister_sysctl_table);