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linux/kernel/sysctl.c
Andi Kleen 25ddbb18aa Make the taint flags reliable 
It's somewhat unlikely that it happens, but right now a race window
between interrupts or machine checks or oopses could corrupt the tainted
bitmap because it is modified in a non atomic fashion.

Convert the taint variable to an unsigned long and use only atomic bit
operations on it.

Unfortunately this means the intvec sysctl functions cannot be used on it
anymore.

It turned out the taint sysctl handler could actually be simplified a bit
(since it only increases capabilities) so this patch actually removes
code.

[akpm@linux-foundation.org: remove unneeded include]
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16 11:21:31 -07:00

3002 lines
71 KiB
C
Raw Blame History

/*
* sysctl.c: General linux system control interface
*
* Begun 24 March 1995, Stephen Tweedie
* Added /proc support, Dec 1995
* Added bdflush entry and intvec min/max checking, 2/23/96, Tom Dyas.
* Added hooks for /proc/sys/net (minor, minor patch), 96/4/1, Mike Shaver.
* Added kernel/java-{interpreter,appletviewer}, 96/5/10, Mike Shaver.
* Dynamic registration fixes, Stephen Tweedie.
* Added kswapd-interval, ctrl-alt-del, printk stuff, 1/8/97, Chris Horn.
* Made sysctl support optional via CONFIG_SYSCTL, 1/10/97, Chris
* Horn.
* Added proc_doulongvec_ms_jiffies_minmax, 09/08/99, Carlos H. Bauer.
* Added proc_doulongvec_minmax, 09/08/99, Carlos H. Bauer.
* Changed linked lists to use list.h instead of lists.h, 02/24/00, Bill
* Wendling.
* The list_for_each() macro wasn't appropriate for the sysctl loop.
* Removed it and replaced it with older style, 03/23/00, Bill Wendling
*/
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/swap.h>
#include <linux/slab.h>
#include <linux/sysctl.h>
#include <linux/proc_fs.h>
#include <linux/security.h>
#include <linux/ctype.h>
#include <linux/utsname.h>
#include <linux/smp_lock.h>
#include <linux/fs.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/kobject.h>
#include <linux/net.h>
#include <linux/sysrq.h>
#include <linux/highuid.h>
#include <linux/writeback.h>
#include <linux/hugetlb.h>
#include <linux/initrd.h>
#include <linux/key.h>
#include <linux/times.h>
#include <linux/limits.h>
#include <linux/dcache.h>
#include <linux/syscalls.h>
#include <linux/vmstat.h>
#include <linux/nfs_fs.h>
#include <linux/acpi.h>
#include <linux/reboot.h>
#include <linux/ftrace.h>
#include <asm/uaccess.h>
#include <asm/processor.h>
#ifdef CONFIG_X86
#include <asm/nmi.h>
#include <asm/stacktrace.h>
#include <asm/io.h>
#endif
static int deprecated_sysctl_warning(struct __sysctl_args *args);
#if defined(CONFIG_SYSCTL)
/* External variables not in a header file. */
extern int C_A_D;
extern int print_fatal_signals;
extern int sysctl_overcommit_memory;
extern int sysctl_overcommit_ratio;
extern int sysctl_panic_on_oom;
extern int sysctl_oom_kill_allocating_task;
extern int sysctl_oom_dump_tasks;
extern int max_threads;
extern int core_uses_pid;
extern int suid_dumpable;
extern char core_pattern[];
extern int pid_max;
extern int min_free_kbytes;
extern int pid_max_min, pid_max_max;
extern int sysctl_drop_caches;
extern int percpu_pagelist_fraction;
extern int compat_log;
extern int latencytop_enabled;
extern int sysctl_nr_open_min, sysctl_nr_open_max;
#ifdef CONFIG_RCU_TORTURE_TEST
extern int rcutorture_runnable;
#endif /* #ifdef CONFIG_RCU_TORTURE_TEST */
/* Constants used for minimum and maximum */
#if defined(CONFIG_HIGHMEM) || defined(CONFIG_DETECT_SOFTLOCKUP)
static int one = 1;
#endif
#ifdef CONFIG_DETECT_SOFTLOCKUP
static int sixty = 60;
static int neg_one = -1;
#endif
#if defined(CONFIG_MMU) && defined(CONFIG_FILE_LOCKING)
static int two = 2;
#endif
static int zero;
static int one_hundred = 100;
/* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
static int maxolduid = 65535;
static int minolduid;
static int min_percpu_pagelist_fract = 8;
static int ngroups_max = NGROUPS_MAX;
#ifdef CONFIG_MODULES
extern char modprobe_path[];
#endif
#ifdef CONFIG_CHR_DEV_SG
extern int sg_big_buff;
#endif
#ifdef CONFIG_SPARC
#include <asm/system.h>
#endif
#ifdef __hppa__
extern int pwrsw_enabled;
extern int unaligned_enabled;
#endif
#ifdef CONFIG_S390
#ifdef CONFIG_MATHEMU
extern int sysctl_ieee_emulation_warnings;
#endif
extern int sysctl_userprocess_debug;
extern int spin_retry;
#endif
#ifdef CONFIG_BSD_PROCESS_ACCT
extern int acct_parm[];
#endif
#ifdef CONFIG_IA64
extern int no_unaligned_warning;
#endif
#ifdef CONFIG_RT_MUTEXES
extern int max_lock_depth;
#endif
#ifdef CONFIG_PROC_SYSCTL
static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos);
static int proc_taint(struct ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos);
#endif
static struct ctl_table root_table[];
static struct ctl_table_root sysctl_table_root;
static struct ctl_table_header root_table_header = {
.count = 1,
.ctl_table = root_table,
.ctl_entry = LIST_HEAD_INIT(sysctl_table_root.default_set.list),
.root = &sysctl_table_root,
.set = &sysctl_table_root.default_set,
};
static struct ctl_table_root sysctl_table_root = {
.root_list = LIST_HEAD_INIT(sysctl_table_root.root_list),
.default_set.list = LIST_HEAD_INIT(root_table_header.ctl_entry),
};
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[];
#ifdef CONFIG_INOTIFY_USER
extern struct ctl_table inotify_table[];
#endif
#ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
int sysctl_legacy_va_layout;
#endif
extern int prove_locking;
extern int lock_stat;
/* The default sysctl tables: */
static struct ctl_table root_table[] = {
{
.ctl_name = CTL_KERN,
.procname = "kernel",
.mode = 0555,
.child = kern_table,
},
{
.ctl_name = CTL_VM,
.procname = "vm",
.mode = 0555,
.child = vm_table,
},
{
.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,
},
/*
* NOTE: do not add new entries to this table unless you have read
* Documentation/sysctl/ctl_unnumbered.txt
*/
{ .ctl_name = 0 }
};
#ifdef CONFIG_SCHED_DEBUG
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 */
#endif
static struct ctl_table kern_table[] = {
#ifdef CONFIG_SCHED_DEBUG
{
.ctl_name = CTL_UNNUMBERED,
.procname = "sched_min_granularity_ns",
.data = &sysctl_sched_min_granularity,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = &sched_nr_latency_handler,
.strategy = &sysctl_intvec,
.extra1 = &min_sched_granularity_ns,
.extra2 = &max_sched_granularity_ns,
},
{
.ctl_name = CTL_UNNUMBERED,
.procname = "sched_latency_ns",
.data = &sysctl_sched_latency,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = &sched_nr_latency_handler,
.strategy = &sysctl_intvec,
.extra1 = &min_sched_granularity_ns,
.extra2 = &max_sched_granularity_ns,
},
{
.ctl_name = CTL_UNNUMBERED,
.procname = "sched_wakeup_granularity_ns",
.data = &sysctl_sched_wakeup_granularity,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = &proc_dointvec_minmax,
.strategy = &sysctl_intvec,
.extra1 = &min_wakeup_granularity_ns,
.extra2 = &max_wakeup_granularity_ns,
},
{
.ctl_name = CTL_UNNUMBERED,
.procname = "sched_shares_ratelimit",
.data = &sysctl_sched_shares_ratelimit,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = CTL_UNNUMBERED,
.procname = "sched_child_runs_first",
.data = &sysctl_sched_child_runs_first,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = CTL_UNNUMBERED,
.procname = "sched_features",
.data = &sysctl_sched_features,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = CTL_UNNUMBERED,
.procname = "sched_migration_cost",
.data = &sysctl_sched_migration_cost,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = CTL_UNNUMBERED,
.procname = "sched_nr_migrate",
.data = &sysctl_sched_nr_migrate,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#endif
{
.ctl_name = CTL_UNNUMBERED,
.procname = "sched_rt_period_us",
.data = &sysctl_sched_rt_period,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = &sched_rt_handler,
},
{
.ctl_name = CTL_UNNUMBERED,
.procname = "sched_rt_runtime_us",
.data = &sysctl_sched_rt_runtime,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &sched_rt_handler,
},
{
.ctl_name = CTL_UNNUMBERED,
.procname = "sched_compat_yield",
.data = &sysctl_sched_compat_yield,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#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,
},
#endif
{
.ctl_name = KERN_PANIC,
.procname = "panic",
.data = &panic_timeout,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = KERN_CORE_USES_PID,
.procname = "core_uses_pid",
.data = &core_uses_pid,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = KERN_CORE_PATTERN,
.procname = "core_pattern",
.data = core_pattern,
.maxlen = CORENAME_MAX_SIZE,
.mode = 0644,
.proc_handler = &proc_dostring,
.strategy = &sysctl_string,
},
#ifdef CONFIG_PROC_SYSCTL
{
.procname = "tainted",
.maxlen = sizeof(long),
.mode = 0644,
.proc_handler = &proc_taint,
},
#endif
#ifdef CONFIG_LATENCYTOP
{
.procname = "latencytop",
.data = &latencytop_enabled,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#endif
#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
{
.ctl_name = CTL_UNNUMBERED,
.procname = "print-fatal-signals",
.data = &print_fatal_signals,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#ifdef CONFIG_SPARC
{
.ctl_name = KERN_SPARC_REBOOT,
.procname = "reboot-cmd",
.data = reboot_command,
.maxlen = 256,
.mode = 0644,
.proc_handler = &proc_dostring,
.strategy = &sysctl_string,
},
{
.ctl_name = KERN_SPARC_STOP_A,
.procname = "stop-a",
.data = &stop_a_enabled,
.maxlen = sizeof (int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = KERN_SPARC_SCONS_PWROFF,
.procname = "scons-poweroff",
.data = &scons_pwroff,
.maxlen = sizeof (int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#endif
#ifdef __hppa__
{
.ctl_name = KERN_HPPA_PWRSW,
.procname = "soft-power",
.data = &pwrsw_enabled,
.maxlen = sizeof (int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = KERN_HPPA_UNALIGNED,
.procname = "unaligned-trap",
.data = &unaligned_enabled,
.maxlen = sizeof (int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#endif
{
.ctl_name = KERN_CTLALTDEL,
.procname = "ctrl-alt-del",
.data = &C_A_D,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#ifdef CONFIG_FTRACE
{
.ctl_name = CTL_UNNUMBERED,
.procname = "ftrace_enabled",
.data = &ftrace_enabled,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &ftrace_enable_sysctl,
},
#endif
#ifdef CONFIG_MODULES
{
.ctl_name = KERN_MODPROBE,
.procname = "modprobe",
.data = &modprobe_path,
.maxlen = KMOD_PATH_LEN,
.mode = 0644,
.proc_handler = &proc_dostring,
.strategy = &sysctl_string,
},
#endif
#if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
{
.ctl_name = KERN_HOTPLUG,
.procname = "hotplug",
.data = &uevent_helper,
.maxlen = UEVENT_HELPER_PATH_LEN,
.mode = 0644,
.proc_handler = &proc_dostring,
.strategy = &sysctl_string,
},
#endif
#ifdef CONFIG_CHR_DEV_SG
{
.ctl_name = KERN_SG_BIG_BUFF,
.procname = "sg-big-buff",
.data = &sg_big_buff,
.maxlen = sizeof (int),
.mode = 0444,
.proc_handler = &proc_dointvec,
},
#endif
#ifdef CONFIG_BSD_PROCESS_ACCT
{
.ctl_name = KERN_ACCT,
.procname = "acct",
.data = &acct_parm,
.maxlen = 3*sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#endif
#ifdef CONFIG_MAGIC_SYSRQ
{
.ctl_name = KERN_SYSRQ,
.procname = "sysrq",
.data = &__sysrq_enabled,
.maxlen = sizeof (int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#endif
#ifdef CONFIG_PROC_SYSCTL
{
.procname = "cad_pid",
.data = NULL,
.maxlen = sizeof (int),
.mode = 0600,
.proc_handler = &proc_do_cad_pid,
},
#endif
{
.ctl_name = KERN_MAX_THREADS,
.procname = "threads-max",
.data = &max_threads,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = KERN_RANDOM,
.procname = "random",
.mode = 0555,
.child = random_table,
},
{
.ctl_name = KERN_OVERFLOWUID,
.procname = "overflowuid",
.data = &overflowuid,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec_minmax,
.strategy = &sysctl_intvec,
.extra1 = &minolduid,
.extra2 = &maxolduid,
},
{
.ctl_name = KERN_OVERFLOWGID,
.procname = "overflowgid",
.data = &overflowgid,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec_minmax,
.strategy = &sysctl_intvec,
.extra1 = &minolduid,
.extra2 = &maxolduid,
},
#ifdef CONFIG_S390
#ifdef CONFIG_MATHEMU
{
.ctl_name = KERN_IEEE_EMULATION_WARNINGS,
.procname = "ieee_emulation_warnings",
.data = &sysctl_ieee_emulation_warnings,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#endif
{
.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,
},
#if defined CONFIG_PRINTK
{
.ctl_name = KERN_PRINTK,
.procname = "printk",
.data = &console_loglevel,
.maxlen = 4*sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = KERN_PRINTK_RATELIMIT,
.procname = "printk_ratelimit",
.data = &printk_ratelimit_state.interval,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec_jiffies,
.strategy = &sysctl_jiffies,
},
{
.ctl_name = KERN_PRINTK_RATELIMIT_BURST,
.procname = "printk_ratelimit_burst",
.data = &printk_ratelimit_state.burst,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#endif
{
.ctl_name = KERN_NGROUPS_MAX,
.procname = "ngroups_max",
.data = &ngroups_max,
.maxlen = sizeof (int),
.mode = 0444,
.proc_handler = &proc_dointvec,
},
#if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
{
.ctl_name = KERN_UNKNOWN_NMI_PANIC,
.procname = "unknown_nmi_panic",
.data = &unknown_nmi_panic,
.maxlen = sizeof (int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.procname = "nmi_watchdog",
.data = &nmi_watchdog_enabled,
.maxlen = sizeof (int),
.mode = 0644,
.proc_handler = &proc_nmi_enabled,
},
#endif
#if defined(CONFIG_X86)
{
.ctl_name = KERN_PANIC_ON_NMI,
.procname = "panic_on_unrecovered_nmi",
.data = &panic_on_unrecovered_nmi,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = KERN_BOOTLOADER_TYPE,
.procname = "bootloader_type",
.data = &bootloader_type,
.maxlen = sizeof (int),
.mode = 0444,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = CTL_UNNUMBERED,
.procname = "kstack_depth_to_print",
.data = &kstack_depth_to_print,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = CTL_UNNUMBERED,
.procname = "io_delay_type",
.data = &io_delay_type,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#endif
#if defined(CONFIG_MMU)
{
.ctl_name = KERN_RANDOMIZE,
.procname = "randomize_va_space",
.data = &randomize_va_space,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#endif
#if defined(CONFIG_S390) && defined(CONFIG_SMP)
{
.ctl_name = KERN_SPIN_RETRY,
.procname = "spin_retry",
.data = &spin_retry,
.maxlen = sizeof (int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#endif
#if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
{
.procname = "acpi_video_flags",
.data = &acpi_realmode_flags,
.maxlen = sizeof (unsigned long),
.mode = 0644,
.proc_handler = &proc_doulongvec_minmax,
},
#endif
#ifdef CONFIG_IA64
{
.ctl_name = KERN_IA64_UNALIGNED,
.procname = "ignore-unaligned-usertrap",
.data = &no_unaligned_warning,
.maxlen = sizeof (int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#endif
#ifdef CONFIG_DETECT_SOFTLOCKUP
{
.ctl_name = CTL_UNNUMBERED,
.procname = "softlockup_panic",
.data = &softlockup_panic,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec_minmax,
.strategy = &sysctl_intvec,
.extra1 = &zero,
.extra2 = &one,
},
{
.ctl_name = CTL_UNNUMBERED,
.procname = "softlockup_thresh",
.data = &softlockup_thresh,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec_minmax,
.strategy = &sysctl_intvec,
.extra1 = &neg_one,
.extra2 = &sixty,
},
{
.ctl_name = CTL_UNNUMBERED,
.procname = "hung_task_check_count",
.data = &sysctl_hung_task_check_count,
.maxlen = sizeof(unsigned long),
.mode = 0644,
.proc_handler = &proc_doulongvec_minmax,
.strategy = &sysctl_intvec,
},
{
.ctl_name = CTL_UNNUMBERED,
.procname = "hung_task_timeout_secs",
.data = &sysctl_hung_task_timeout_secs,
.maxlen = sizeof(unsigned long),
.mode = 0644,
.proc_handler = &proc_doulongvec_minmax,
.strategy = &sysctl_intvec,
},
{
.ctl_name = CTL_UNNUMBERED,
.procname = "hung_task_warnings",
.data = &sysctl_hung_task_warnings,
.maxlen = sizeof(unsigned long),
.mode = 0644,
.proc_handler = &proc_doulongvec_minmax,
.strategy = &sysctl_intvec,
},
#endif
#ifdef CONFIG_COMPAT
{
.ctl_name = KERN_COMPAT_LOG,
.procname = "compat-log",
.data = &compat_log,
.maxlen = sizeof (int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#endif
#ifdef CONFIG_RT_MUTEXES
{
.ctl_name = KERN_MAX_LOCK_DEPTH,
.procname = "max_lock_depth",
.data = &max_lock_depth,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#endif
{
.ctl_name = CTL_UNNUMBERED,
.procname = "poweroff_cmd",
.data = &poweroff_cmd,
.maxlen = POWEROFF_CMD_PATH_LEN,
.mode = 0644,
.proc_handler = &proc_dostring,
.strategy = &sysctl_string,
},
#ifdef CONFIG_KEYS
{
.ctl_name = CTL_UNNUMBERED,
.procname = "keys",
.mode = 0555,
.child = key_sysctls,
},
#endif
#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
/*
* NOTE: do not add new entries to this table unless you have read
* Documentation/sysctl/ctl_unnumbered.txt
*/
{ .ctl_name = 0 }
};
static struct ctl_table vm_table[] = {
{
.ctl_name = VM_OVERCOMMIT_MEMORY,
.procname = "overcommit_memory",
.data = &sysctl_overcommit_memory,
.maxlen = sizeof(sysctl_overcommit_memory),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = VM_PANIC_ON_OOM,
.procname = "panic_on_oom",
.data = &sysctl_panic_on_oom,
.maxlen = sizeof(sysctl_panic_on_oom),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = 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,
},
{
.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,
},
{
.ctl_name = VM_OVERCOMMIT_RATIO,
.procname = "overcommit_ratio",
.data = &sysctl_overcommit_ratio,
.maxlen = sizeof(sysctl_overcommit_ratio),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = VM_PAGE_CLUSTER,
.procname = "page-cluster",
.data = &page_cluster,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = VM_DIRTY_BACKGROUND,
.procname = "dirty_background_ratio",
.data = &dirty_background_ratio,
.maxlen = sizeof(dirty_background_ratio),
.mode = 0644,
.proc_handler = &proc_dointvec_minmax,
.strategy = &sysctl_intvec,
.extra1 = &zero,
.extra2 = &one_hundred,
},
{
.ctl_name = VM_DIRTY_RATIO,
.procname = "dirty_ratio",
.data = &vm_dirty_ratio,
.maxlen = sizeof(vm_dirty_ratio),
.mode = 0644,
.proc_handler = &dirty_ratio_handler,
.strategy = &sysctl_intvec,
.extra1 = &zero,
.extra2 = &one_hundred,
},
{
.procname = "dirty_writeback_centisecs",
.data = &dirty_writeback_interval,
.maxlen = sizeof(dirty_writeback_interval),
.mode = 0644,
.proc_handler = &dirty_writeback_centisecs_handler,
},
{
.procname = "dirty_expire_centisecs",
.data = &dirty_expire_interval,
.maxlen = sizeof(dirty_expire_interval),
.mode = 0644,
.proc_handler = &proc_dointvec_userhz_jiffies,
},
{
.ctl_name = VM_NR_PDFLUSH_THREADS,
.procname = "nr_pdflush_threads",
.data = &nr_pdflush_threads,
.maxlen = sizeof nr_pdflush_threads,
.mode = 0444 /* read-only*/,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = VM_SWAPPINESS,
.procname = "swappiness",
.data = &vm_swappiness,
.maxlen = sizeof(vm_swappiness),
.mode = 0644,
.proc_handler = &proc_dointvec_minmax,
.strategy = &sysctl_intvec,
.extra1 = &zero,
.extra2 = &one_hundred,
},
#ifdef CONFIG_HUGETLB_PAGE
{
.procname = "nr_hugepages",
.data = NULL,
.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,
},
{
.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,
},
{
.ctl_name = CTL_UNNUMBERED,
.procname = "nr_overcommit_hugepages",
.data = NULL,
.maxlen = sizeof(unsigned long),
.mode = 0644,
.proc_handler = &hugetlb_overcommit_handler,
.extra1 = (void *)&hugetlb_zero,
.extra2 = (void *)&hugetlb_infinity,
},
#endif
{
.ctl_name = VM_LOWMEM_RESERVE_RATIO,
.procname = "lowmem_reserve_ratio",
.data = &sysctl_lowmem_reserve_ratio,
.maxlen = sizeof(sysctl_lowmem_reserve_ratio),
.mode = 0644,
.proc_handler = &lowmem_reserve_ratio_sysctl_handler,
.strategy = &sysctl_intvec,
},
{
.ctl_name = VM_DROP_PAGECACHE,
.procname = "drop_caches",
.data = &sysctl_drop_caches,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = drop_caches_sysctl_handler,
.strategy = &sysctl_intvec,
},
{
.ctl_name = VM_MIN_FREE_KBYTES,
.procname = "min_free_kbytes",
.data = &min_free_kbytes,
.maxlen = sizeof(min_free_kbytes),
.mode = 0644,
.proc_handler = &min_free_kbytes_sysctl_handler,
.strategy = &sysctl_intvec,
.extra1 = &zero,
},
{
.ctl_name = VM_PERCPU_PAGELIST_FRACTION,
.procname = "percpu_pagelist_fraction",
.data = &percpu_pagelist_fraction,
.maxlen = sizeof(percpu_pagelist_fraction),
.mode = 0644,
.proc_handler = &percpu_pagelist_fraction_sysctl_handler,
.strategy = &sysctl_intvec,
.extra1 = &min_percpu_pagelist_fract,
},
#ifdef CONFIG_MMU
{
.ctl_name = VM_MAX_MAP_COUNT,
.procname = "max_map_count",
.data = &sysctl_max_map_count,
.maxlen = sizeof(sysctl_max_map_count),
.mode = 0644,
.proc_handler = &proc_dointvec
},
#endif
{
.ctl_name = VM_LAPTOP_MODE,
.procname = "laptop_mode",
.data = &laptop_mode,
.maxlen = sizeof(laptop_mode),
.mode = 0644,
.proc_handler = &proc_dointvec_jiffies,
.strategy = &sysctl_jiffies,
},
{
.ctl_name = VM_BLOCK_DUMP,
.procname = "block_dump",
.data = &block_dump,
.maxlen = sizeof(block_dump),
.mode = 0644,
.proc_handler = &proc_dointvec,
.strategy = &sysctl_intvec,
.extra1 = &zero,
},
{
.ctl_name = VM_VFS_CACHE_PRESSURE,
.procname = "vfs_cache_pressure",
.data = &sysctl_vfs_cache_pressure,
.maxlen = sizeof(sysctl_vfs_cache_pressure),
.mode = 0644,
.proc_handler = &proc_dointvec,
.strategy = &sysctl_intvec,
.extra1 = &zero,
},
#ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
{
.ctl_name = VM_LEGACY_VA_LAYOUT,
.procname = "legacy_va_layout",
.data = &sysctl_legacy_va_layout,
.maxlen = sizeof(sysctl_legacy_va_layout),
.mode = 0644,
.proc_handler = &proc_dointvec,
.strategy = &sysctl_intvec,
.extra1 = &zero,
},
#endif
#ifdef CONFIG_NUMA
{
.ctl_name = VM_ZONE_RECLAIM_MODE,
.procname = "zone_reclaim_mode",
.data = &zone_reclaim_mode,
.maxlen = sizeof(zone_reclaim_mode),
.mode = 0644,
.proc_handler = &proc_dointvec,
.strategy = &sysctl_intvec,
.extra1 = &zero,
},
{
.ctl_name = VM_MIN_UNMAPPED,
.procname = "min_unmapped_ratio",
.data = &sysctl_min_unmapped_ratio,
.maxlen = sizeof(sysctl_min_unmapped_ratio),
.mode = 0644,
.proc_handler = &sysctl_min_unmapped_ratio_sysctl_handler,
.strategy = &sysctl_intvec,
.extra1 = &zero,
.extra2 = &one_hundred,
},
{
.ctl_name = VM_MIN_SLAB,
.procname = "min_slab_ratio",
.data = &sysctl_min_slab_ratio,
.maxlen = sizeof(sysctl_min_slab_ratio),
.mode = 0644,
.proc_handler = &sysctl_min_slab_ratio_sysctl_handler,
.strategy = &sysctl_intvec,
.extra1 = &zero,
.extra2 = &one_hundred,
},
#endif
#ifdef CONFIG_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
#ifdef CONFIG_SECURITY
{
.ctl_name = CTL_UNNUMBERED,
.procname = "mmap_min_addr",
.data = &mmap_min_addr,
.maxlen = sizeof(unsigned long),
.mode = 0644,
.proc_handler = &proc_doulongvec_minmax,
},
#endif
#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
#if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
(defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
{
.ctl_name = VM_VDSO_ENABLED,
.procname = "vdso_enabled",
.data = &vdso_enabled,
.maxlen = sizeof(vdso_enabled),
.mode = 0644,
.proc_handler = &proc_dointvec,
.strategy = &sysctl_intvec,
.extra1 = &zero,
},
#endif
#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
/*
* NOTE: do not add new entries to this table unless you have read
* Documentation/sysctl/ctl_unnumbered.txt
*/
{ .ctl_name = 0 }
};
#if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
static struct ctl_table binfmt_misc_table[] = {
{ .ctl_name = 0 }
};
#endif
static struct ctl_table fs_table[] = {
{
.ctl_name = FS_NRINODE,
.procname = "inode-nr",
.data = &inodes_stat,
.maxlen = 2*sizeof(int),
.mode = 0444,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = FS_STATINODE,
.procname = "inode-state",
.data = &inodes_stat,
.maxlen = 7*sizeof(int),
.mode = 0444,
.proc_handler = &proc_dointvec,
},
{
.procname = "file-nr",
.data = &files_stat,
.maxlen = 3*sizeof(int),
.mode = 0444,
.proc_handler = &proc_nr_files,
},
{
.ctl_name = FS_MAXFILE,
.procname = "file-max",
.data = &files_stat.max_files,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = CTL_UNNUMBERED,
.procname = "nr_open",
.data = &sysctl_nr_open,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec_minmax,
.extra1 = &sysctl_nr_open_min,
.extra2 = &sysctl_nr_open_max,
},
{
.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,
},
#ifdef CONFIG_FILE_LOCKING
{
.ctl_name = FS_LEASES,
.procname = "leases-enable",
.data = &leases_enable,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#endif
#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
#ifdef CONFIG_FILE_LOCKING
{
.ctl_name = FS_LEASE_TIME,
.procname = "lease-break-time",
.data = &lease_break_time,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec_minmax,
.strategy = &sysctl_intvec,
.extra1 = &zero,
.extra2 = &two,
},
#endif
{
.procname = "aio-nr",
.data = &aio_nr,
.maxlen = sizeof(aio_nr),
.mode = 0444,
.proc_handler = &proc_doulongvec_minmax,
},
{
.procname = "aio-max-nr",
.data = &aio_max_nr,
.maxlen = sizeof(aio_max_nr),
.mode = 0644,
.proc_handler = &proc_doulongvec_minmax,
},
#ifdef CONFIG_INOTIFY_USER
{
.ctl_name = FS_INOTIFY,
.procname = "inotify",
.mode = 0555,
.child = inotify_table,
},
#endif
#endif
{
.ctl_name = KERN_SETUID_DUMPABLE,
.procname = "suid_dumpable",
.data = &suid_dumpable,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
{
.ctl_name = CTL_UNNUMBERED,
.procname = "binfmt_misc",
.mode = 0555,
.child = binfmt_misc_table,
},
#endif
/*
* NOTE: do not add new entries to this table unless you have read
* Documentation/sysctl/ctl_unnumbered.txt
*/
{ .ctl_name = 0 }
};
static struct ctl_table debug_table[] = {
#if defined(CONFIG_X86) || defined(CONFIG_PPC)
{
.ctl_name = CTL_UNNUMBERED,
.procname = "exception-trace",
.data = &show_unhandled_signals,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
#endif
{ .ctl_name = 0 }
};
static struct ctl_table dev_table[] = {
{ .ctl_name = 0 }
};
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);
} else {
/* anything non-NULL; we'll never dereference it */
p->unregistering = ERR_PTR(-EINVAL);
}
/*
* do not remove from the list until nobody holds it; walking the
* list in do_sysctl() relies on that.
*/
list_del_init(&p->ctl_entry);
}
void 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;
}
void sysctl_head_finish(struct ctl_table_header *head)
{
if (!head)
return;
spin_lock(&sysctl_lock);
unuse_table(head);
spin_unlock(&sysctl_lock);
}
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;
}
static struct list_head *
lookup_header_list(struct ctl_table_root *root, struct nsproxy *namespaces)
{
struct ctl_table_set *set = lookup_header_set(root, namespaces);
return &set->list;
}
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;
struct ctl_table_header *head;
struct list_head *tmp;
spin_lock(&sysctl_lock);
if (prev) {
head = prev;
tmp = &prev->ctl_entry;
unuse_table(prev);
goto next;
}
tmp = &root_table_header.ctl_entry;
for (;;) {
head = list_entry(tmp, struct ctl_table_header, ctl_entry);
if (!use_table(head))
goto next;
spin_unlock(&sysctl_lock);
return head;
next:
root = head->root;
tmp = tmp->next;
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;
}
out:
spin_unlock(&sysctl_lock);
return NULL;
}
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);
}
#ifdef CONFIG_SYSCTL_SYSCALL
/* Perform the actual read/write of a sysctl table entry. */
static int do_sysctl_strategy(struct ctl_table_root *root,
struct ctl_table *table,
int __user *name, int nlen,
void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen)
{
int op = 0, rc;
if (oldval)
op |= MAY_READ;
if (newval)
op |= MAY_WRITE;
if (sysctl_perm(root, table, op))
return -EPERM;
if (table->strategy) {
rc = table->strategy(table, name, nlen, oldval, oldlenp,
newval, newlen);
if (rc < 0)
return rc;
if (rc > 0)
return 0;
}
/* If there is no strategy routine, or if the strategy returns
* zero, proceed with automatic r/w */
if (table->data && table->maxlen) {
rc = sysctl_data(table, name, nlen, oldval, oldlenp,
newval, newlen);
if (rc < 0)
return rc;
}
return 0;
}
static int parse_table(int __user *name, int nlen,
void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen,
struct ctl_table_root *root,
struct ctl_table *table)
{
int n;
repeat:
if (!nlen)
return -ENOTDIR;
if (get_user(n, name))
return -EFAULT;
for ( ; table->ctl_name || table->procname; table++) {
if (!table->ctl_name)
continue;
if (n == table->ctl_name) {
int error;
if (table->child) {
if (sysctl_perm(root, table, MAY_EXEC))
return -EPERM;
name++;
nlen--;
table = table->child;
goto repeat;
}
error = do_sysctl_strategy(root, table, name, nlen,
oldval, oldlenp,
newval, newlen);
return error;
}
}
return -ENOTDIR;
}
int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen)
{
struct ctl_table_header *head;
int error = -ENOTDIR;
if (nlen <= 0 || nlen >= CTL_MAXNAME)
return -ENOTDIR;
if (oldval) {
int old_len;
if (!oldlenp || get_user(old_len, oldlenp))
return -EFAULT;
}
for (head = sysctl_head_next(NULL); head;
head = sysctl_head_next(head)) {
error = parse_table(name, nlen, oldval, oldlenp,
newval, newlen,
head->root, head->ctl_table);
if (error != -ENOTDIR) {
sysctl_head_finish(head);
break;
}
}
return error;
}
asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
{
struct __sysctl_args tmp;
int error;
if (copy_from_user(&tmp, args, sizeof(tmp)))
return -EFAULT;
error = deprecated_sysctl_warning(&tmp);
if (error)
goto out;
lock_kernel();
error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
tmp.newval, tmp.newlen);
unlock_kernel();
out:
return error;
}
#endif /* CONFIG_SYSCTL_SYSCALL */
/*
* sysctl_perm does NOT grant the superuser all rights automatically, because
* some sysctl variables are readonly even to root.
*/
static int test_perm(int mode, int op)
{
if (!current->euid)
mode >>= 6;
else if (in_egroup_p(0))
mode >>= 3;
if ((op & ~mode & (MAY_READ|MAY_WRITE|MAY_EXEC)) == 0)
return 0;
return -EACCES;
}
int sysctl_perm(struct ctl_table_root *root, struct ctl_table *table, int op)
{
int error;
int mode;
error = security_sysctl(table, op & (MAY_READ | MAY_WRITE | MAY_EXEC));
if (error)
return error;
if (root->permissions)
mode = root->permissions(root, current->nsproxy, table);
else
mode = table->mode;
return test_perm(mode, op);
}
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);
#ifdef CONFIG_SYSCTL_SYSCALL_CHECK
{
int err;
err = sysctl_check_table(current->nsproxy, root_table);
}
#endif
return 0;
}
core_initcall(sysctl_init);
static struct ctl_table *is_branch_in(struct ctl_table *branch,
struct ctl_table *table)
{
struct ctl_table *p;
const char *s = branch->procname;
/* branch should have named subdirectory as its first element */
if (!s || !branch->child)
return NULL;
/* ... and nothing else */
if (branch[1].procname || branch[1].ctl_name)
return NULL;
/* 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)
return p;
}
return NULL;
}
/* 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;
struct ctl_table *next;
int is_better = 0;
int not_in_parent = !p->attached_by;
while ((next = is_branch_in(by, to)) != NULL) {
if (by == q->attached_by)
is_better = 1;
if (to == p->attached_by)
not_in_parent = 1;
by = by->child;
to = next->child;
}
if (is_better && not_in_parent) {
q->attached_by = by;
q->attached_to = to;
q->parent = p;
}
}
/**
* __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
* @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.
*
* The members of the &struct ctl_table structure are used as follows:
*
* ctl_name - This is the numeric sysctl value used by sysctl(2). The number
* must be unique within that level of sysctl
*
* procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
* enter a sysctl file
*
* data - a pointer to data for use by proc_handler
*
* maxlen - the maximum size in bytes of the data
*
* mode - the file permissions for the /proc/sys file, and for sysctl(2)
*
* child - a pointer to the child sysctl table if this entry is a directory, or
* %NULL.
*
* proc_handler - the text handler routine (described below)
*
* strategy - the strategy routine (described below)
*
* de - for internal use by the sysctl routines
*
* extra1, extra2 - extra pointers usable by the proc handler routines
*
* Leaf nodes in the sysctl tree will be represented by a single file
* under /proc; non-leaf nodes will be represented by directories.
*
* sysctl(2) can automatically manage read and write requests through
* the sysctl table. The data and maxlen fields of the ctl_table
* struct enable minimal validation of the values being written to be
* performed, and the mode field allows minimal authentication.
*
* More sophisticated management can be enabled by the provision of a
* strategy routine with the table entry. This will be called before
* any automatic read or write of the data is performed.
*
* The strategy routine may return
*
* < 0 - Error occurred (error is passed to user process)
*
* 0 - OK - proceed with automatic read or write.
*
* > 0 - OK - read or write has been done by the strategy routine, so
* return immediately.
*
* There must be a proc_handler routine for any terminal nodes
* mirrored under /proc/sys (non-terminals are handled by a built-in
* directory handler). Several default handlers are available to
* cover common cases -
*
* proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
* proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
* proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
*
* It is the handler's job to read the input buffer from user memory
* and process it. The handler should return 0 on success.
*
* This routine returns %NULL on a failure to register, and a pointer
* to the table header on success.
*/
struct ctl_table_header *__register_sysctl_paths(
struct ctl_table_root *root,
struct nsproxy *namespaces,
const struct ctl_path *path, struct ctl_table *table)
{
struct ctl_table_header *header;
struct ctl_table *new, **prevp;
unsigned int n, npath;
struct ctl_table_set *set;
/* 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)
return NULL;
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;
header->ctl_table_arg = table;
INIT_LIST_HEAD(&header->ctl_entry);
header->used = 0;
header->unregistering = NULL;
header->root = root;
sysctl_set_parent(NULL, header->ctl_table);
header->count = 1;
#ifdef CONFIG_SYSCTL_SYSCALL_CHECK
if (sysctl_check_table(namespaces, header->ctl_table)) {
kfree(header);
return NULL;
}
#endif
spin_lock(&sysctl_lock);
header->set = lookup_header_set(root, namespaces);
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++;
list_add_tail(&header->ctl_entry, &header->set->list);
spin_unlock(&sysctl_lock);
return header;
}
/**
* 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);
}
/**
* 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);
}
/**
* unregister_sysctl_table - unregister a sysctl table hierarchy
* @header: the header returned from register_sysctl_table
*
* Unregisters the sysctl table and all children. proc entries may not
* actually be removed until they are no longer used by anyone.
*/
void unregister_sysctl_table(struct ctl_table_header * header)
{
might_sleep();
if (header == NULL)
return;
spin_lock(&sysctl_lock);
start_unregistering(header);
if (!--header->parent->count) {
WARN_ON(1);
kfree(header->parent);
}
if (!--header->count)
kfree(header);
spin_unlock(&sysctl_lock);
}
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;
}
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;
}
#else /* !CONFIG_SYSCTL */
struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
{
return NULL;
}
struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
struct ctl_table *table)
{
return NULL;
}
void unregister_sysctl_table(struct ctl_table_header * table)
{
}
void setup_sysctl_set(struct ctl_table_set *p,
struct ctl_table_set *parent,
int (*is_seen)(struct ctl_table_set *))
{
}
void sysctl_head_put(struct ctl_table_header *head)
{
}
#endif /* CONFIG_SYSCTL */
/*
* /proc/sys support
*/
#ifdef CONFIG_PROC_SYSCTL
static int _proc_do_string(void* data, int maxlen, int write,
struct file *filp, void __user *buffer,
size_t *lenp, loff_t *ppos)
{
size_t len;
char __user *p;
char c;
if (!data || !maxlen || !*lenp) {
*lenp = 0;
return 0;
}
if (write) {
len = 0;
p = buffer;
while (len < *lenp) {
if (get_user(c, p++))
return -EFAULT;
if (c == 0 || c == '\n')
break;
len++;
}
if (len >= maxlen)
len = maxlen-1;
if(copy_from_user(data, buffer, len))
return -EFAULT;
((char *) data)[len] = 0;
*ppos += *lenp;
} else {
len = strlen(data);
if (len > maxlen)
len = maxlen;
if (*ppos > len) {
*lenp = 0;
return 0;
}
data += *ppos;
len -= *ppos;
if (len > *lenp)
len = *lenp;
if (len)
if(copy_to_user(buffer, data, len))
return -EFAULT;
if (len < *lenp) {
if(put_user('\n', ((char __user *) buffer) + len))
return -EFAULT;
len++;
}
*lenp = len;
*ppos += len;
}
return 0;
}
/**
* proc_dostring - read a string sysctl
* @table: the sysctl table
* @write: %TRUE if this is a write to the sysctl file
* @filp: the file structure
* @buffer: the user buffer
* @lenp: the size of the user buffer
* @ppos: file position
*
* Reads/writes a string from/to the user buffer. If the kernel
* buffer provided is not large enough to hold the string, the
* string is truncated. The copied string is %NULL-terminated.
* If the string is being read by the user process, it is copied
* and a newline '\n' is added. It is truncated if the buffer is
* not large enough.
*
* Returns 0 on success.
*/
int proc_dostring(struct ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return _proc_do_string(table->data, table->maxlen, write, filp,
buffer, lenp, ppos);
}
static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
int *valp,
int write, void *data)
{
if (write) {
*valp = *negp ? -*lvalp : *lvalp;
} else {
int val = *valp;
if (val < 0) {
*negp = -1;
*lvalp = (unsigned long)-val;
} else {
*negp = 0;
*lvalp = (unsigned long)val;
}
}
return 0;
}
static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
int write, struct file *filp, void __user *buffer,
size_t *lenp, loff_t *ppos,
int (*conv)(int *negp, unsigned long *lvalp, int *valp,
int write, void *data),
void *data)
{
#define TMPBUFLEN 21
int *i, vleft, first=1, neg, val;
unsigned long lval;
size_t left, len;
char buf[TMPBUFLEN], *p;
char __user *s = buffer;
if (!tbl_data || !table->maxlen || !*lenp ||
(*ppos && !write)) {
*lenp = 0;
return 0;
}
i = (int *) tbl_data;
vleft = table->maxlen / sizeof(*i);
left = *lenp;
if (!conv)
conv = do_proc_dointvec_conv;
for (; left && vleft--; i++, first=0) {
if (write) {
while (left) {
char c;
if (get_user(c, s))
return -EFAULT;
if (!isspace(c))
break;
left--;
s++;
}
if (!left)
break;
neg = 0;
len = left;
if (len > sizeof(buf) - 1)
len = sizeof(buf) - 1;
if (copy_from_user(buf, s, len))
return -EFAULT;
buf[len] = 0;
p = buf;
if (*p == '-' && left > 1) {
neg = 1;
p++;
}
if (*p < '0' || *p > '9')
break;
lval = simple_strtoul(p, &p, 0);
len = p-buf;
if ((len < left) && *p && !isspace(*p))
break;
if (neg)
val = -val;
s += len;
left -= len;
if (conv(&neg, &lval, i, 1, data))
break;
} else {
p = buf;
if (!first)
*p++ = '\t';
if (conv(&neg, &lval, i, 0, data))
break;
sprintf(p, "%s%lu", neg ? "-" : "", lval);
len = strlen(buf);
if (len > left)
len = left;
if(copy_to_user(s, buf, len))
return -EFAULT;
left -= len;
s += len;
}
}
if (!write && !first && left) {
if(put_user('\n', s))
return -EFAULT;
left--, s++;
}
if (write) {
while (left) {
char c;
if (get_user(c, s++))
return -EFAULT;
if (!isspace(c))
break;
left--;
}
}
if (write && first)
return -EINVAL;
*lenp -= left;
*ppos += *lenp;
return 0;
#undef TMPBUFLEN
}
static int do_proc_dointvec(struct ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos,
int (*conv)(int *negp, unsigned long *lvalp, int *valp,
int write, void *data),
void *data)
{
return __do_proc_dointvec(table->data, table, write, filp,
buffer, lenp, ppos, conv, data);
}
/**
* proc_dointvec - read a vector of integers
* @table: the sysctl table
* @write: %TRUE if this is a write to the sysctl file
* @filp: the file structure
* @buffer: the user buffer
* @lenp: the size of the user buffer
* @ppos: file position
*
* Reads/writes up to table->maxlen/sizeof(unsigned int) integer
* values from/to the user buffer, treated as an ASCII string.
*
* Returns 0 on success.
*/
int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
NULL,NULL);
}
/*
* Taint values can only be increased
* This means we can safely use a temporary.
*/
static int proc_taint(struct ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
struct ctl_table t;
unsigned long tmptaint = get_taint();
int err;
if (write && !capable(CAP_SYS_ADMIN))
return -EPERM;
t = *table;
t.data = &tmptaint;
err = proc_doulongvec_minmax(&t, write, filp, buffer, lenp, ppos);
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;
}
struct do_proc_dointvec_minmax_conv_param {
int *min;
int *max;
};
static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
int *valp,
int write, void *data)
{
struct do_proc_dointvec_minmax_conv_param *param = data;
if (write) {
int val = *negp ? -*lvalp : *lvalp;
if ((param->min && *param->min > val) ||
(param->max && *param->max < val))
return -EINVAL;
*valp = val;
} else {
int val = *valp;
if (val < 0) {
*negp = -1;
*lvalp = (unsigned long)-val;
} else {
*negp = 0;
*lvalp = (unsigned long)val;
}
}
return 0;
}
/**
* proc_dointvec_minmax - read a vector of integers with min/max values
* @table: the sysctl table
* @write: %TRUE if this is a write to the sysctl file
* @filp: the file structure
* @buffer: the user buffer
* @lenp: the size of the user buffer
* @ppos: file position
*
* Reads/writes up to table->maxlen/sizeof(unsigned int) integer
* values from/to the user buffer, treated as an ASCII string.
*
* This routine will ensure the values are within the range specified by
* table->extra1 (min) and table->extra2 (max).
*
* Returns 0 on success.
*/
int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
struct do_proc_dointvec_minmax_conv_param param = {
.min = (int *) table->extra1,
.max = (int *) table->extra2,
};
return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
do_proc_dointvec_minmax_conv, &param);
}
static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
struct file *filp,
void __user *buffer,
size_t *lenp, loff_t *ppos,
unsigned long convmul,
unsigned long convdiv)
{
#define TMPBUFLEN 21
unsigned long *i, *min, *max, val;
int vleft, first=1, neg;
size_t len, left;
char buf[TMPBUFLEN], *p;
char __user *s = buffer;
if (!data || !table->maxlen || !*lenp ||
(*ppos && !write)) {
*lenp = 0;
return 0;
}
i = (unsigned long *) data;
min = (unsigned long *) table->extra1;
max = (unsigned long *) table->extra2;
vleft = table->maxlen / sizeof(unsigned long);
left = *lenp;
for (; left && vleft--; i++, min++, max++, first=0) {
if (write) {
while (left) {
char c;
if (get_user(c, s))
return -EFAULT;
if (!isspace(c))
break;
left--;
s++;
}
if (!left)
break;
neg = 0;
len = left;
if (len > TMPBUFLEN-1)
len = TMPBUFLEN-1;
if (copy_from_user(buf, s, len))
return -EFAULT;
buf[len] = 0;
p = buf;
if (*p == '-' && left > 1) {
neg = 1;
p++;
}
if (*p < '0' || *p > '9')
break;
val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
len = p-buf;
if ((len < left) && *p && !isspace(*p))
break;
if (neg)
val = -val;
s += len;
left -= len;
if(neg)
continue;
if ((min && val < *min) || (max && val > *max))
continue;
*i = val;
} else {
p = buf;
if (!first)
*p++ = '\t';
sprintf(p, "%lu", convdiv * (*i) / convmul);
len = strlen(buf);
if (len > left)
len = left;
if(copy_to_user(s, buf, len))
return -EFAULT;
left -= len;
s += len;
}
}
if (!write && !first && left) {
if(put_user('\n', s))
return -EFAULT;
left--, s++;
}
if (write) {
while (left) {
char c;
if (get_user(c, s++))
return -EFAULT;
if (!isspace(c))
break;
left--;
}
}
if (write && first)
return -EINVAL;
*lenp -= left;
*ppos += *lenp;
return 0;
#undef TMPBUFLEN
}
static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
struct file *filp,
void __user *buffer,
size_t *lenp, loff_t *ppos,
unsigned long convmul,
unsigned long convdiv)
{
return __do_proc_doulongvec_minmax(table->data, table, write,
filp, buffer, lenp, ppos, convmul, convdiv);
}
/**
* proc_doulongvec_minmax - read a vector of long integers with min/max values
* @table: the sysctl table
* @write: %TRUE if this is a write to the sysctl file
* @filp: the file structure
* @buffer: the user buffer
* @lenp: the size of the user buffer
* @ppos: file position
*
* Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
* values from/to the user buffer, treated as an ASCII string.
*
* This routine will ensure the values are within the range specified by
* table->extra1 (min) and table->extra2 (max).
*
* Returns 0 on success.
*/
int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
}
/**
* proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
* @table: the sysctl table
* @write: %TRUE if this is a write to the sysctl file
* @filp: the file structure
* @buffer: the user buffer
* @lenp: the size of the user buffer
* @ppos: file position
*
* Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
* values from/to the user buffer, treated as an ASCII string. The values
* are treated as milliseconds, and converted to jiffies when they are stored.
*
* This routine will ensure the values are within the range specified by
* table->extra1 (min) and table->extra2 (max).
*
* Returns 0 on success.
*/
int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
struct file *filp,
void __user *buffer,
size_t *lenp, loff_t *ppos)
{
return do_proc_doulongvec_minmax(table, write, filp, buffer,
lenp, ppos, HZ, 1000l);
}
static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
int *valp,
int write, void *data)
{
if (write) {
if (*lvalp > LONG_MAX / HZ)
return 1;
*valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
} else {
int val = *valp;
unsigned long lval;
if (val < 0) {
*negp = -1;
lval = (unsigned long)-val;
} else {
*negp = 0;
lval = (unsigned long)val;
}
*lvalp = lval / HZ;
}
return 0;
}
static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
int *valp,
int write, void *data)
{
if (write) {
if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
return 1;
*valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
} else {
int val = *valp;
unsigned long lval;
if (val < 0) {
*negp = -1;
lval = (unsigned long)-val;
} else {
*negp = 0;
lval = (unsigned long)val;
}
*lvalp = jiffies_to_clock_t(lval);
}
return 0;
}
static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
int *valp,
int write, void *data)
{
if (write) {
*valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
} else {
int val = *valp;
unsigned long lval;
if (val < 0) {
*negp = -1;
lval = (unsigned long)-val;
} else {
*negp = 0;
lval = (unsigned long)val;
}
*lvalp = jiffies_to_msecs(lval);
}
return 0;
}
/**
* proc_dointvec_jiffies - read a vector of integers as seconds
* @table: the sysctl table
* @write: %TRUE if this is a write to the sysctl file
* @filp: the file structure
* @buffer: the user buffer
* @lenp: the size of the user buffer
* @ppos: file position
*
* Reads/writes up to table->maxlen/sizeof(unsigned int) integer
* values from/to the user buffer, treated as an ASCII string.
* The values read are assumed to be in seconds, and are converted into
* jiffies.
*
* Returns 0 on success.
*/
int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
do_proc_dointvec_jiffies_conv,NULL);
}
/**
* proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
* @table: the sysctl table
* @write: %TRUE if this is a write to the sysctl file
* @filp: the file structure
* @buffer: the user buffer
* @lenp: the size of the user buffer
* @ppos: pointer to the file position
*
* Reads/writes up to table->maxlen/sizeof(unsigned int) integer
* values from/to the user buffer, treated as an ASCII string.
* The values read are assumed to be in 1/USER_HZ seconds, and
* are converted into jiffies.
*
* Returns 0 on success.
*/
int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
do_proc_dointvec_userhz_jiffies_conv,NULL);
}
/**
* proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
* @table: the sysctl table
* @write: %TRUE if this is a write to the sysctl file
* @filp: the file structure
* @buffer: the user buffer
* @lenp: the size of the user buffer
* @ppos: file position
* @ppos: the current position in the file
*
* Reads/writes up to table->maxlen/sizeof(unsigned int) integer
* values from/to the user buffer, treated as an ASCII string.
* The values read are assumed to be in 1/1000 seconds, and
* are converted into jiffies.
*
* Returns 0 on success.
*/
int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
do_proc_dointvec_ms_jiffies_conv, NULL);
}
static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
struct pid *new_pid;
pid_t tmp;
int r;
tmp = pid_vnr(cad_pid);
r = __do_proc_dointvec(&tmp, table, write, filp, buffer,
lenp, ppos, NULL, NULL);
if (r || !write)
return r;
new_pid = find_get_pid(tmp);
if (!new_pid)
return -ESRCH;
put_pid(xchg(&cad_pid, new_pid));
return 0;
}
#else /* CONFIG_PROC_FS */
int proc_dostring(struct ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return -ENOSYS;
}
int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return -ENOSYS;
}
int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return -ENOSYS;
}
int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return -ENOSYS;
}
int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return -ENOSYS;
}
int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return -ENOSYS;
}
int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return -ENOSYS;
}
int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
struct file *filp,
void __user *buffer,
size_t *lenp, loff_t *ppos)
{
return -ENOSYS;
}
#endif /* CONFIG_PROC_FS */
#ifdef CONFIG_SYSCTL_SYSCALL
/*
* General sysctl support routines
*/
/* The generic sysctl data routine (used if no strategy routine supplied) */
int sysctl_data(struct ctl_table *table, int __user *name, int nlen,
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;
}
/* The generic string strategy routine: */
int sysctl_string(struct ctl_table *table, int __user *name, int nlen,
void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen)
{
if (!table->data || !table->maxlen)
return -ENOTDIR;
if (oldval && oldlenp) {
size_t bufsize;
if (get_user(bufsize, oldlenp))
return -EFAULT;
if (bufsize) {
size_t len = strlen(table->data), copied;
/* This shouldn't trigger for a well-formed sysctl */
if (len > table->maxlen)
len = table->maxlen;
/* Copy up to a max of bufsize-1 bytes of the string */
copied = (len >= bufsize) ? bufsize - 1 : len;
if (copy_to_user(oldval, table->data, copied) ||
put_user(0, (char __user *)(oldval + copied)))
return -EFAULT;
if (put_user(len, oldlenp))
return -EFAULT;
}
}
if (newval && newlen) {
size_t len = newlen;
if (len > table->maxlen)
len = table->maxlen;
if(copy_from_user(table->data, newval, len))
return -EFAULT;
if (len == table->maxlen)
len--;
((char *) table->data)[len] = 0;
}
return 1;
}
/*
* This function makes sure that all of the integers in the vector
* are between the minimum and maximum values given in the arrays
* table->extra1 and table->extra2, respectively.
*/
int sysctl_intvec(struct ctl_table *table, int __user *name, int nlen,
void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen)
{
if (newval && newlen) {
int __user *vec = (int __user *) newval;
int *min = (int *) table->extra1;
int *max = (int *) table->extra2;
size_t length;
int i;
if (newlen % sizeof(int) != 0)
return -EINVAL;
if (!table->extra1 && !table->extra2)
return 0;
if (newlen > table->maxlen)
newlen = table->maxlen;
length = newlen / sizeof(int);
for (i = 0; i < length; i++) {
int value;
if (get_user(value, vec + i))
return -EFAULT;
if (min && value < min[i])
return -EINVAL;
if (max && value > max[i])
return -EINVAL;
}
}
return 0;
}
/* Strategy function to convert jiffies to seconds */
int sysctl_jiffies(struct ctl_table *table, int __user *name, int nlen,
void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen)
{
if (oldval && oldlenp) {
size_t olen;
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))
return -EFAULT;
}
}
if (newval && newlen) {
int new;
if (newlen != sizeof(int))
return -EINVAL;
if (get_user(new, (int __user *)newval))
return -EFAULT;
*(int *)(table->data) = new*HZ;
}
return 1;
}
/* Strategy function to convert jiffies to seconds */
int sysctl_ms_jiffies(struct ctl_table *table, int __user *name, int nlen,
void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen)
{
if (oldval && oldlenp) {
size_t olen;
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))
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;
}
#else /* CONFIG_SYSCTL_SYSCALL */
asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
{
struct __sysctl_args tmp;
int error;
if (copy_from_user(&tmp, args, sizeof(tmp)))
return -EFAULT;
error = deprecated_sysctl_warning(&tmp);
/* If no error reading the parameters then just -ENOSYS ... */
if (!error)
error = -ENOSYS;
return error;
}
int sysctl_data(struct ctl_table *table, int __user *name, int nlen,
void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen)
{
return -ENOSYS;
}
int sysctl_string(struct ctl_table *table, int __user *name, int nlen,
void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen)
{
return -ENOSYS;
}
int sysctl_intvec(struct ctl_table *table, int __user *name, int nlen,
void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen)
{
return -ENOSYS;
}
int sysctl_jiffies(struct ctl_table *table, int __user *name, int nlen,
void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen)
{
return -ENOSYS;
}
int sysctl_ms_jiffies(struct ctl_table *table, int __user *name, int nlen,
void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen)
{
return -ENOSYS;
}
#endif /* CONFIG_SYSCTL_SYSCALL */
static int deprecated_sysctl_warning(struct __sysctl_args *args)
{
static int msg_count;
int name[CTL_MAXNAME];
int i;
/* Check args->nlen. */
if (args->nlen < 0 || args->nlen > CTL_MAXNAME)
return -ENOTDIR;
/* Read in the sysctl name for better debug message logging */
for (i = 0; i < args->nlen; i++)
if (get_user(name[i], args->name + i))
return -EFAULT;
/* Ignore accesses to kernel.version */
if ((args->nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
return 0;
if (msg_count < 5) {
msg_count++;
printk(KERN_INFO
"warning: process `%s' used the deprecated sysctl "
"system call with ", current->comm);
for (i = 0; i < args->nlen; i++)
printk("%d.", name[i]);
printk("\n");
}
return 0;
}
/*
* No sense putting this after each symbol definition, twice,
* exception granted :-)
*/
EXPORT_SYMBOL(proc_dointvec);
EXPORT_SYMBOL(proc_dointvec_jiffies);
EXPORT_SYMBOL(proc_dointvec_minmax);
EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
EXPORT_SYMBOL(proc_dostring);
EXPORT_SYMBOL(proc_doulongvec_minmax);
EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
EXPORT_SYMBOL(register_sysctl_table);
EXPORT_SYMBOL(register_sysctl_paths);
EXPORT_SYMBOL(sysctl_intvec);
EXPORT_SYMBOL(sysctl_jiffies);
EXPORT_SYMBOL(sysctl_ms_jiffies);
EXPORT_SYMBOL(sysctl_string);
EXPORT_SYMBOL(sysctl_data);
EXPORT_SYMBOL(unregister_sysctl_table);
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