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-rw-r--r--kernel/sysctl.c3031
1 files changed, 3031 insertions, 0 deletions
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
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index 0000000..68fd128
--- /dev/null
+++ b/kernel/sysctl.c
@@ -0,0 +1,3031 @@
+/*
+ * 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 CONFIG_EPOLL
+extern struct ctl_table epoll_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_shares_thresh",
+ .data = &sysctl_sched_shares_thresh,
+ .maxlen = sizeof(unsigned int),
+ .mode = 0644,
+ .proc_handler = &proc_dointvec_minmax,
+ .strategy = &sysctl_intvec,
+ .extra1 = &zero,
+ },
+ {
+ .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_FUNCTION_TRACER
+ {
+ .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
+#ifdef CONFIG_UNEVICTABLE_LRU
+ {
+ .ctl_name = CTL_UNNUMBERED,
+ .procname = "scan_unevictable_pages",
+ .data = &scan_unevictable_pages,
+ .maxlen = sizeof(scan_unevictable_pages),
+ .mode = 0644,
+ .proc_handler = &scan_unevictable_handler,
+ },
+#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
+#ifdef CONFIG_AIO
+ {
+ .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,
+ },
+#endif /* CONFIG_AIO */
+#ifdef CONFIG_INOTIFY_USER
+ {
+ .ctl_name = FS_INOTIFY,
+ .procname = "inotify",
+ .mode = 0555,
+ .child = inotify_table,
+ },
+#endif
+#ifdef CONFIG_EPOLL
+ {
+ .procname = "epoll",
+ .mode = 0555,
+ .child = epoll_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,
+ void __user *oldval, size_t __user *oldlenp,
+ void __user *newval, size_t newlen)
+{
+ int op = 0, rc;
+
+ if (oldval)
+ op |= MAY_READ;
+ if (newval)
+ op |= MAY_WRITE;
+ if (sysctl_perm(root, table, op))
+ return -EPERM;
+
+ if (table->strategy) {
+ rc = table->strategy(table, oldval, oldlenp, newval, newlen);
+ if (rc < 0)
+ return rc;
+ if (rc > 0)
+ return 0;
+ }
+
+ /* If there is no strategy routine, or if the strategy returns
+ * zero, proceed with automatic r/w */
+ if (table->data && table->maxlen) {
+ rc = sysctl_data(table, oldval, oldlenp, newval, newlen);
+ if (rc < 0)
+ return rc;
+ }
+ return 0;
+}
+
+static int parse_table(int __user *name, int nlen,
+ void __user *oldval, size_t __user *oldlenp,
+ void __user *newval, size_t newlen,
+ struct ctl_table_root *root,
+ struct ctl_table *table)
+{
+ int n;
+repeat:
+ if (!nlen)
+ return -ENOTDIR;
+ if (get_user(n, name))
+ return -EFAULT;
+ for ( ; table->ctl_name || table->procname; table++) {
+ if (!table->ctl_name)
+ continue;
+ if (n == table->ctl_name) {
+ int error;
+ if (table->child) {
+ if (sysctl_perm(root, table, MAY_EXEC))
+ return -EPERM;
+ name++;
+ nlen--;
+ table = table->child;
+ goto repeat;
+ }
+ error = do_sysctl_strategy(root, table,
+ oldval, oldlenp,
+ newval, newlen);
+ return error;
+ }
+ }
+ return -ENOTDIR;
+}
+
+int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
+ void __user *newval, size_t newlen)
+{
+ struct ctl_table_header *head;
+ int error = -ENOTDIR;
+
+ if (nlen <= 0 || nlen >= CTL_MAXNAME)
+ return -ENOTDIR;
+ if (oldval) {
+ int old_len;
+ if (!oldlenp || get_user(old_len, oldlenp))
+ return -EFAULT;
+ }
+
+ for (head = sysctl_head_next(NULL); head;
+ head = sysctl_head_next(head)) {
+ error = parse_table(name, nlen, oldval, oldlenp,
+ newval, newlen,
+ head->root, head->ctl_table);
+ if (error != -ENOTDIR) {
+ sysctl_head_finish(head);
+ break;
+ }
+ }
+ return error;
+}
+
+SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
+{
+ struct __sysctl_args tmp;
+ int error;
+
+ if (copy_from_user(&tmp, args, sizeof(tmp)))
+ return -EFAULT;
+
+ error = deprecated_sysctl_warning(&tmp);
+ if (error)
+ goto out;
+
+ lock_kernel();
+ error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
+ tmp.newval, tmp.newlen);
+ unlock_kernel();
+out:
+ return error;
+}
+#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,
+ 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,
+ 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,
+ 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,
+ 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,
+ 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 */
+
+
+SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
+{
+ struct __sysctl_args tmp;
+ int error;
+
+ if (copy_from_user(&tmp, args, sizeof(tmp)))
+ return -EFAULT;
+
+ error = deprecated_sysctl_warning(&tmp);
+
+ /* If no error reading the parameters then just -ENOSYS ... */
+ if (!error)
+ error = -ENOSYS;
+
+ return error;
+}
+
+int sysctl_data(struct ctl_table *table,
+ void __user *oldval, size_t __user *oldlenp,
+ void __user *newval, size_t newlen)
+{
+ return -ENOSYS;
+}
+
+int sysctl_string(struct ctl_table *table,
+ void __user *oldval, size_t __user *oldlenp,
+ void __user *newval, size_t newlen)
+{
+ return -ENOSYS;
+}
+
+int sysctl_intvec(struct ctl_table *table,
+ void __user *oldval, size_t __user *oldlenp,
+ void __user *newval, size_t newlen)
+{
+ return -ENOSYS;
+}
+
+int sysctl_jiffies(struct ctl_table *table,
+ void __user *oldval, size_t __user *oldlenp,
+ void __user *newval, size_t newlen)
+{
+ return -ENOSYS;
+}
+
+int sysctl_ms_jiffies(struct ctl_table *table,
+ 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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