diff options
Diffstat (limited to 'kernel/sysctl.c')
| -rw-r--r-- | kernel/sysctl.c | 2873 |
1 files changed, 697 insertions, 2176 deletions
diff --git a/kernel/sysctl.c b/kernel/sysctl.c index ac09d98490aa..2cd767b9680e 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -1,1676 +1,70 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * 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/bitmap.h> -#include <linux/signal.h> -#include <linux/printk.h> #include <linux/proc_fs.h> -#include <linux/security.h> #include <linux/ctype.h> -#include <linux/kmemcheck.h> -#include <linux/kmemleak.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/ratelimit.h> -#include <linux/compaction.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/dnotify.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 <linux/perf_event.h> -#include <linux/kprobes.h> -#include <linux/pipe_fs_i.h> -#include <linux/oom.h> -#include <linux/kmod.h> #include <linux/capability.h> -#include <linux/binfmts.h> -#include <linux/sched/sysctl.h> -#include <asm/uaccess.h> -#include <asm/processor.h> +#include "../lib/kstrtox.h" -#ifdef CONFIG_X86 -#include <asm/nmi.h> -#include <asm/stacktrace.h> -#include <asm/io.h> -#endif -#ifdef CONFIG_SPARC -#include <asm/setup.h> -#endif -#ifdef CONFIG_BSD_PROCESS_ACCT -#include <linux/acct.h> -#endif -#ifdef CONFIG_RT_MUTEXES -#include <linux/rtmutex.h> -#endif -#if defined(CONFIG_PROVE_LOCKING) || defined(CONFIG_LOCK_STAT) -#include <linux/lockdep.h> -#endif -#ifdef CONFIG_CHR_DEV_SG -#include <scsi/sg.h> -#endif +#include <linux/uaccess.h> +#include <asm/processor.h> -#ifdef CONFIG_LOCKUP_DETECTOR -#include <linux/nmi.h> -#endif +/* shared constants to be used in various sysctls */ +const int sysctl_vals[] = { 0, 1, 2, 3, 4, 100, 200, 1000, 3000, INT_MAX, 65535, -1 }; +EXPORT_SYMBOL(sysctl_vals); +const unsigned long sysctl_long_vals[] = { 0, 1, LONG_MAX }; +EXPORT_SYMBOL_GPL(sysctl_long_vals); #if defined(CONFIG_SYSCTL) -/* External variables not in a header file. */ -extern int sysctl_overcommit_memory; -extern int sysctl_overcommit_ratio; -extern int max_threads; -extern int suid_dumpable; -#ifdef CONFIG_COREDUMP -extern int core_uses_pid; -extern char core_pattern[]; -extern unsigned int core_pipe_limit; -#endif -extern int pid_max; -extern int pid_max_min, pid_max_max; -extern int percpu_pagelist_fraction; -extern int compat_log; -extern int latencytop_enabled; -extern int sysctl_nr_open_min, sysctl_nr_open_max; -#ifndef CONFIG_MMU -extern int sysctl_nr_trim_pages; -#endif -#ifdef CONFIG_BLOCK -extern int blk_iopoll_enabled; -#endif - -/* Constants used for minimum and maximum */ -#ifdef CONFIG_LOCKUP_DETECTOR -static int sixty = 60; -#endif - -static int zero; -static int __maybe_unused one = 1; -static int __maybe_unused two = 2; -static int __maybe_unused three = 3; -static unsigned long one_ul = 1; -static int one_hundred = 100; -#ifdef CONFIG_PRINTK -static int ten_thousand = 10000; -#endif - -/* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */ -static unsigned long dirty_bytes_min = 2 * PAGE_SIZE; - -/* 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; +/* Constants used for minimum and maximum */ +static const int ngroups_max = NGROUPS_MAX; static const int cap_last_cap = CAP_LAST_CAP; -#ifdef CONFIG_INOTIFY_USER -#include <linux/inotify.h> -#endif -#ifdef CONFIG_SPARC -#endif - -#ifdef CONFIG_SPARC64 -extern int sysctl_tsb_ratio; -#endif - -#ifdef __hppa__ -extern int pwrsw_enabled; -#endif - -#ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW -extern int unaligned_enabled; -#endif - -#ifdef CONFIG_IA64 -extern int unaligned_dump_stack; -#endif - -#ifdef CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN -extern int no_unaligned_warning; -#endif - #ifdef CONFIG_PROC_SYSCTL -static int proc_do_cad_pid(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos); -static int proc_taint(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos); -#endif - -#ifdef CONFIG_PRINTK -static int proc_dointvec_minmax_sysadmin(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos); -#endif - -static int proc_dointvec_minmax_coredump(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos); -#ifdef CONFIG_COREDUMP -static int proc_dostring_coredump(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos); -#endif - -#ifdef CONFIG_MAGIC_SYSRQ -/* Note: sysrq code uses it's own private copy */ -static int __sysrq_enabled = SYSRQ_DEFAULT_ENABLE; - -static int sysrq_sysctl_handler(ctl_table *table, int write, - void __user *buffer, size_t *lenp, - loff_t *ppos) -{ - int error; - - error = proc_dointvec(table, write, buffer, lenp, ppos); - if (error) - return error; - - if (write) - sysrq_toggle_support(__sysrq_enabled); - - return 0; -} - -#endif - -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_EPOLL -extern struct ctl_table epoll_table[]; -#endif - -#ifdef HAVE_ARCH_PICK_MMAP_LAYOUT -int sysctl_legacy_va_layout; -#endif - -/* The default sysctl tables: */ - -static struct ctl_table sysctl_base_table[] = { - { - .procname = "kernel", - .mode = 0555, - .child = kern_table, - }, - { - .procname = "vm", - .mode = 0555, - .child = vm_table, - }, - { - .procname = "fs", - .mode = 0555, - .child = fs_table, - }, - { - .procname = "debug", - .mode = 0555, - .child = debug_table, - }, - { - .procname = "dev", - .mode = 0555, - .child = dev_table, - }, - { } -}; - -#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 */ -#ifdef CONFIG_SMP -static int min_sched_tunable_scaling = SCHED_TUNABLESCALING_NONE; -static int max_sched_tunable_scaling = SCHED_TUNABLESCALING_END-1; -#endif /* CONFIG_SMP */ -#endif /* CONFIG_SCHED_DEBUG */ - -#ifdef CONFIG_COMPACTION -static int min_extfrag_threshold; -static int max_extfrag_threshold = 1000; -#endif - -static struct ctl_table kern_table[] = { - { - .procname = "sched_child_runs_first", - .data = &sysctl_sched_child_runs_first, - .maxlen = sizeof(unsigned int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, -#ifdef CONFIG_SCHED_DEBUG - { - .procname = "sched_min_granularity_ns", - .data = &sysctl_sched_min_granularity, - .maxlen = sizeof(unsigned int), - .mode = 0644, - .proc_handler = sched_proc_update_handler, - .extra1 = &min_sched_granularity_ns, - .extra2 = &max_sched_granularity_ns, - }, - { - .procname = "sched_latency_ns", - .data = &sysctl_sched_latency, - .maxlen = sizeof(unsigned int), - .mode = 0644, - .proc_handler = sched_proc_update_handler, - .extra1 = &min_sched_granularity_ns, - .extra2 = &max_sched_granularity_ns, - }, - { - .procname = "sched_wakeup_granularity_ns", - .data = &sysctl_sched_wakeup_granularity, - .maxlen = sizeof(unsigned int), - .mode = 0644, - .proc_handler = sched_proc_update_handler, - .extra1 = &min_wakeup_granularity_ns, - .extra2 = &max_wakeup_granularity_ns, - }, -#ifdef CONFIG_SMP - { - .procname = "sched_tunable_scaling", - .data = &sysctl_sched_tunable_scaling, - .maxlen = sizeof(enum sched_tunable_scaling), - .mode = 0644, - .proc_handler = sched_proc_update_handler, - .extra1 = &min_sched_tunable_scaling, - .extra2 = &max_sched_tunable_scaling, - }, - { - .procname = "sched_migration_cost_ns", - .data = &sysctl_sched_migration_cost, - .maxlen = sizeof(unsigned int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, - { - .procname = "sched_nr_migrate", - .data = &sysctl_sched_nr_migrate, - .maxlen = sizeof(unsigned int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, - { - .procname = "sched_time_avg_ms", - .data = &sysctl_sched_time_avg, - .maxlen = sizeof(unsigned int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, - { - .procname = "sched_shares_window_ns", - .data = &sysctl_sched_shares_window, - .maxlen = sizeof(unsigned int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, - { - .procname = "timer_migration", - .data = &sysctl_timer_migration, - .maxlen = sizeof(unsigned int), - .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = &zero, - .extra2 = &one, - }, -#endif /* CONFIG_SMP */ -#ifdef CONFIG_NUMA_BALANCING - { - .procname = "numa_balancing_scan_delay_ms", - .data = &sysctl_numa_balancing_scan_delay, - .maxlen = sizeof(unsigned int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, - { - .procname = "numa_balancing_scan_period_min_ms", - .data = &sysctl_numa_balancing_scan_period_min, - .maxlen = sizeof(unsigned int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, - { - .procname = "numa_balancing_scan_period_reset", - .data = &sysctl_numa_balancing_scan_period_reset, - .maxlen = sizeof(unsigned int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, - { - .procname = "numa_balancing_scan_period_max_ms", - .data = &sysctl_numa_balancing_scan_period_max, - .maxlen = sizeof(unsigned int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, - { - .procname = "numa_balancing_scan_size_mb", - .data = &sysctl_numa_balancing_scan_size, - .maxlen = sizeof(unsigned int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, -#endif /* CONFIG_NUMA_BALANCING */ -#endif /* CONFIG_SCHED_DEBUG */ - { - .procname = "sched_rt_period_us", - .data = &sysctl_sched_rt_period, - .maxlen = sizeof(unsigned int), - .mode = 0644, - .proc_handler = sched_rt_handler, - }, - { - .procname = "sched_rt_runtime_us", - .data = &sysctl_sched_rt_runtime, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = sched_rt_handler, - }, - { - .procname = "sched_rr_timeslice_ms", - .data = &sched_rr_timeslice, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = sched_rr_handler, - }, -#ifdef CONFIG_SCHED_AUTOGROUP - { - .procname = "sched_autogroup_enabled", - .data = &sysctl_sched_autogroup_enabled, - .maxlen = sizeof(unsigned int), - .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = &zero, - .extra2 = &one, - }, -#endif -#ifdef CONFIG_CFS_BANDWIDTH - { - .procname = "sched_cfs_bandwidth_slice_us", - .data = &sysctl_sched_cfs_bandwidth_slice, - .maxlen = sizeof(unsigned int), - .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = &one, - }, -#endif -#ifdef CONFIG_PROVE_LOCKING - { - .procname = "prove_locking", - .data = &prove_locking, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, -#endif -#ifdef CONFIG_LOCK_STAT - { - .procname = "lock_stat", - .data = &lock_stat, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, -#endif - { - .procname = "panic", - .data = &panic_timeout, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, -#ifdef CONFIG_COREDUMP - { - .procname = "core_uses_pid", - .data = &core_uses_pid, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, - { - .procname = "core_pattern", - .data = core_pattern, - .maxlen = CORENAME_MAX_SIZE, - .mode = 0644, - .proc_handler = proc_dostring_coredump, - }, - { - .procname = "core_pipe_limit", - .data = &core_pipe_limit, - .maxlen = sizeof(unsigned int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, -#endif -#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 - { - .procname = "real-root-dev", - .data = &real_root_dev, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, -#endif - { - .procname = "print-fatal-signals", - .data = &print_fatal_signals, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, -#ifdef CONFIG_SPARC - { - .procname = "reboot-cmd", - .data = reboot_command, - .maxlen = 256, - .mode = 0644, - .proc_handler = proc_dostring, - }, - { - .procname = "stop-a", - .data = &stop_a_enabled, - .maxlen = sizeof (int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, - { - .procname = "scons-poweroff", - .data = &scons_pwroff, - .maxlen = sizeof (int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, -#endif -#ifdef CONFIG_SPARC64 - { - .procname = "tsb-ratio", - .data = &sysctl_tsb_ratio, - .maxlen = sizeof (int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, -#endif -#ifdef __hppa__ - { - .procname = "soft-power", - .data = &pwrsw_enabled, - .maxlen = sizeof (int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, -#endif -#ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW - { - .procname = "unaligned-trap", - .data = &unaligned_enabled, - .maxlen = sizeof (int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, -#endif - { - .procname = "ctrl-alt-del", - .data = &C_A_D, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, -#ifdef CONFIG_FUNCTION_TRACER - { - .procname = "ftrace_enabled", - .data = &ftrace_enabled, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = ftrace_enable_sysctl, - }, -#endif -#ifdef CONFIG_STACK_TRACER - { - .procname = "stack_tracer_enabled", - .data = &stack_tracer_enabled, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = stack_trace_sysctl, - }, -#endif -#ifdef CONFIG_TRACING - { - .procname = "ftrace_dump_on_oops", - .data = &ftrace_dump_on_oops, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, - { - .procname = "traceoff_on_warning", - .data = &__disable_trace_on_warning, - .maxlen = sizeof(__disable_trace_on_warning), - .mode = 0644, - .proc_handler = proc_dointvec, - }, -#endif -#ifdef CONFIG_MODULES - { - .procname = "modprobe", - .data = &modprobe_path, - .maxlen = KMOD_PATH_LEN, - .mode = 0644, - .proc_handler = proc_dostring, - }, - { - .procname = "modules_disabled", - .data = &modules_disabled, - .maxlen = sizeof(int), - .mode = 0644, - /* only handle a transition from default "0" to "1" */ - .proc_handler = proc_dointvec_minmax, - .extra1 = &one, - .extra2 = &one, - }, -#endif - - { - .procname = "hotplug", - .data = &uevent_helper, - .maxlen = UEVENT_HELPER_PATH_LEN, - .mode = 0644, - .proc_handler = proc_dostring, - }, - -#ifdef CONFIG_CHR_DEV_SG - { - .procname = "sg-big-buff", - .data = &sg_big_buff, - .maxlen = sizeof (int), - .mode = 0444, - .proc_handler = proc_dointvec, - }, -#endif -#ifdef CONFIG_BSD_PROCESS_ACCT - { - .procname = "acct", - .data = &acct_parm, - .maxlen = 3*sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, -#endif -#ifdef CONFIG_MAGIC_SYSRQ - { - .procname = "sysrq", - .data = &__sysrq_enabled, - .maxlen = sizeof (int), - .mode = 0644, - .proc_handler = sysrq_sysctl_handler, - }, -#endif -#ifdef CONFIG_PROC_SYSCTL - { - .procname = "cad_pid", - .data = NULL, - .maxlen = sizeof (int), - .mode = 0600, - .proc_handler = proc_do_cad_pid, - }, -#endif - { - .procname = "threads-max", - .data = &max_threads, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, - { - .procname = "random", - .mode = 0555, - .child = random_table, - }, - { - .procname = "usermodehelper", - .mode = 0555, - .child = usermodehelper_table, - }, - { - .procname = "overflowuid", - .data = &overflowuid, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = &minolduid, - .extra2 = &maxolduid, - }, - { - .procname = "overflowgid", - .data = &overflowgid, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = &minolduid, - .extra2 = &maxolduid, - }, -#ifdef CONFIG_S390 -#ifdef CONFIG_MATHEMU - { - .procname = "ieee_emulation_warnings", - .data = &sysctl_ieee_emulation_warnings, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, -#endif - { - .procname = "userprocess_debug", - .data = &show_unhandled_signals, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, -#endif - { - .procname = "pid_max", - .data = &pid_max, - .maxlen = sizeof (int), - .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = &pid_max_min, - .extra2 = &pid_max_max, - }, - { - .procname = "panic_on_oops", - .data = &panic_on_oops, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, -#if defined CONFIG_PRINTK - { - .procname = "printk", - .data = &console_loglevel, - .maxlen = 4*sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, - { - .procname = "printk_ratelimit", - .data = &printk_ratelimit_state.interval, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec_jiffies, - }, - { - .procname = "printk_ratelimit_burst", - .data = &printk_ratelimit_state.burst, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, - { - .procname = "printk_delay", - .data = &printk_delay_msec, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = &zero, - .extra2 = &ten_thousand, - }, - { - .procname = "dmesg_restrict", - .data = &dmesg_restrict, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec_minmax_sysadmin, - .extra1 = &zero, - .extra2 = &one, - }, - { - .procname = "kptr_restrict", - .data = &kptr_restrict, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec_minmax_sysadmin, - .extra1 = &zero, - .extra2 = &two, - }, -#endif - { - .procname = "ngroups_max", - .data = &ngroups_max, - .maxlen = sizeof (int), - .mode = 0444, - .proc_handler = proc_dointvec, - }, - { - .procname = "cap_last_cap", - .data = (void *)&cap_last_cap, - .maxlen = sizeof(int), - .mode = 0444, - .proc_handler = proc_dointvec, - }, -#if defined(CONFIG_LOCKUP_DETECTOR) - { - .procname = "watchdog", - .data = &watchdog_user_enabled, - .maxlen = sizeof (int), - .mode = 0644, - .proc_handler = proc_dowatchdog, - .extra1 = &zero, - .extra2 = &one, - }, - { - .procname = "watchdog_thresh", - .data = &watchdog_thresh, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dowatchdog, - .extra1 = &zero, - .extra2 = &sixty, - }, - { - .procname = "softlockup_panic", - .data = &softlockup_panic, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = &zero, - .extra2 = &one, - }, - { - .procname = "nmi_watchdog", - .data = &watchdog_user_enabled, - .maxlen = sizeof (int), - .mode = 0644, - .proc_handler = proc_dowatchdog, - .extra1 = &zero, - .extra2 = &one, - }, -#endif -#if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86) - { - .procname = "unknown_nmi_panic", - .data = &unknown_nmi_panic, - .maxlen = sizeof (int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, -#endif -#if defined(CONFIG_X86) - { - .procname = "panic_on_unrecovered_nmi", - .data = &panic_on_unrecovered_nmi, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, - { - .procname = "panic_on_io_nmi", - .data = &panic_on_io_nmi, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, -#ifdef CONFIG_DEBUG_STACKOVERFLOW - { - .procname = "panic_on_stackoverflow", - .data = &sysctl_panic_on_stackoverflow, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, -#endif - { - .procname = "bootloader_type", - .data = &bootloader_type, - .maxlen = sizeof (int), - .mode = 0444, - .proc_handler = proc_dointvec, - }, - { - .procname = "bootloader_version", - .data = &bootloader_version, - .maxlen = sizeof (int), - .mode = 0444, - .proc_handler = proc_dointvec, - }, - { - .procname = "kstack_depth_to_print", - .data = &kstack_depth_to_print, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, - { - .procname = "io_delay_type", - .data = &io_delay_type, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, -#endif -#if defined(CONFIG_MMU) - { - .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) - { - .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_SYSCTL_ARCH_UNALIGN_NO_WARN - { - .procname = "ignore-unaligned-usertrap", - .data = &no_unaligned_warning, - .maxlen = sizeof (int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, -#endif -#ifdef CONFIG_IA64 - { - .procname = "unaligned-dump-stack", - .data = &unaligned_dump_stack, - .maxlen = sizeof (int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, -#endif -#ifdef CONFIG_DETECT_HUNG_TASK - { - .procname = "hung_task_panic", - .data = &sysctl_hung_task_panic, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = &zero, - .extra2 = &one, - }, - { - .procname = "hung_task_check_count", - .data = &sysctl_hung_task_check_count, - .maxlen = sizeof(unsigned long), - .mode = 0644, - .proc_handler = proc_doulongvec_minmax, - }, - { - .procname = "hung_task_timeout_secs", - .data = &sysctl_hung_task_timeout_secs, - .maxlen = sizeof(unsigned long), - .mode = 0644, - .proc_handler = proc_dohung_task_timeout_secs, - }, - { - .procname = "hung_task_warnings", - .data = &sysctl_hung_task_warnings, - .maxlen = sizeof(unsigned long), - .mode = 0644, - .proc_handler = proc_doulongvec_minmax, - }, -#endif -#ifdef CONFIG_COMPAT - { - .procname = "compat-log", - .data = &compat_log, - .maxlen = sizeof (int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, -#endif -#ifdef CONFIG_RT_MUTEXES - { - .procname = "max_lock_depth", - .data = &max_lock_depth, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, -#endif - { - .procname = "poweroff_cmd", - .data = &poweroff_cmd, - .maxlen = POWEROFF_CMD_PATH_LEN, - .mode = 0644, - .proc_handler = proc_dostring, - }, -#ifdef CONFIG_KEYS - { - .procname = "keys", - .mode = 0555, - .child = key_sysctls, - }, -#endif -#ifdef CONFIG_RCU_TORTURE_TEST - { - .procname = "rcutorture_runnable", - .data = &rcutorture_runnable, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, -#endif -#ifdef CONFIG_PERF_EVENTS - /* - * User-space scripts rely on the existence of this file - * as a feature check for perf_events being enabled. - * - * So it's an ABI, do not remove! - */ - { - .procname = "perf_event_paranoid", - .data = &sysctl_perf_event_paranoid, - .maxlen = sizeof(sysctl_perf_event_paranoid), - .mode = 0644, - .proc_handler = proc_dointvec, - }, - { - .procname = "perf_event_mlock_kb", - .data = &sysctl_perf_event_mlock, - .maxlen = sizeof(sysctl_perf_event_mlock), - .mode = 0644, - .proc_handler = proc_dointvec, - }, - { - .procname = "perf_event_max_sample_rate", - .data = &sysctl_perf_event_sample_rate, - .maxlen = sizeof(sysctl_perf_event_sample_rate), - .mode = 0644, - .proc_handler = perf_proc_update_handler, - }, - { - .procname = "perf_cpu_time_max_percent", - .data = &sysctl_perf_cpu_time_max_percent, - .maxlen = sizeof(sysctl_perf_cpu_time_max_percent), - .mode = 0644, - .proc_handler = perf_cpu_time_max_percent_handler, - .extra1 = &zero, - .extra2 = &one_hundred, - }, -#endif -#ifdef CONFIG_KMEMCHECK - { - .procname = "kmemcheck", - .data = &kmemcheck_enabled, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, -#endif -#ifdef CONFIG_BLOCK - { - .procname = "blk_iopoll", - .data = &blk_iopoll_enabled, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, -#endif - { } -}; -static struct ctl_table vm_table[] = { - { - .procname = "overcommit_memory", - .data = &sysctl_overcommit_memory, - .maxlen = sizeof(sysctl_overcommit_memory), - .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = &zero, - .extra2 = &two, - }, - { - .procname = "panic_on_oom", - .data = &sysctl_panic_on_oom, - .maxlen = sizeof(sysctl_panic_on_oom), - .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = &zero, - .extra2 = &two, - }, - { - .procname = "oom_kill_allocating_task", - .data = &sysctl_oom_kill_allocating_task, - .maxlen = sizeof(sysctl_oom_kill_allocating_task), - .mode = 0644, - .proc_handler = proc_dointvec, - }, - { - .procname = "oom_dump_tasks", - .data = &sysctl_oom_dump_tasks, - .maxlen = sizeof(sysctl_oom_dump_tasks), - .mode = 0644, - .proc_handler = proc_dointvec, - }, - { - .procname = "overcommit_ratio", - .data = &sysctl_overcommit_ratio, - .maxlen = sizeof(sysctl_overcommit_ratio), - .mode = 0644, - .proc_handler = proc_dointvec, - }, - { - .procname = "page-cluster", - .data = &page_cluster, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = &zero, - }, - { - .procname = "dirty_background_ratio", - .data = &dirty_background_ratio, - .maxlen = sizeof(dirty_background_ratio), - .mode = 0644, - .proc_handler = dirty_background_ratio_handler, - .extra1 = &zero, - .extra2 = &one_hundred, - }, - { - .procname = "dirty_background_bytes", - .data = &dirty_background_bytes, - .maxlen = sizeof(dirty_background_bytes), - .mode = 0644, - .proc_handler = dirty_background_bytes_handler, - .extra1 = &one_ul, - }, - { - .procname = "dirty_ratio", - .data = &vm_dirty_ratio, - .maxlen = sizeof(vm_dirty_ratio), - .mode = 0644, - .proc_handler = dirty_ratio_handler, - .extra1 = &zero, - .extra2 = &one_hundred, - }, - { - .procname = "dirty_bytes", - .data = &vm_dirty_bytes, - .maxlen = sizeof(vm_dirty_bytes), - .mode = 0644, - .proc_handler = dirty_bytes_handler, - .extra1 = &dirty_bytes_min, - }, - { - .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_minmax, - .extra1 = &zero, - }, - { - .procname = "nr_pdflush_threads", - .mode = 0444 /* read-only */, - .proc_handler = pdflush_proc_obsolete, - }, - { - .procname = "swappiness", - .data = &vm_swappiness, - .maxlen = sizeof(vm_swappiness), - .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .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, - }, -#ifdef CONFIG_NUMA - { - .procname = "nr_hugepages_mempolicy", - .data = NULL, - .maxlen = sizeof(unsigned long), - .mode = 0644, - .proc_handler = &hugetlb_mempolicy_sysctl_handler, - .extra1 = (void *)&hugetlb_zero, - .extra2 = (void *)&hugetlb_infinity, - }, -#endif - { - .procname = "hugetlb_shm_group", - .data = &sysctl_hugetlb_shm_group, - .maxlen = sizeof(gid_t), - .mode = 0644, - .proc_handler = proc_dointvec, - }, - { - .procname = "hugepages_treat_as_movable", - .data = &hugepages_treat_as_movable, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = hugetlb_treat_movable_handler, - }, - { - .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 - { - .procname = "lowmem_reserve_ratio", - .data = &sysctl_lowmem_reserve_ratio, - .maxlen = sizeof(sysctl_lowmem_reserve_ratio), - .mode = 0644, - .proc_handler = lowmem_reserve_ratio_sysctl_handler, - }, - { - .procname = "drop_caches", - .data = &sysctl_drop_caches, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = drop_caches_sysctl_handler, - .extra1 = &one, - .extra2 = &three, - }, -#ifdef CONFIG_COMPACTION - { - .procname = "compact_memory", - .data = &sysctl_compact_memory, - .maxlen = sizeof(int), - .mode = 0200, - .proc_handler = sysctl_compaction_handler, - }, - { - .procname = "extfrag_threshold", - .data = &sysctl_extfrag_threshold, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = sysctl_extfrag_handler, - .extra1 = &min_extfrag_threshold, - .extra2 = &max_extfrag_threshold, - }, - -#endif /* CONFIG_COMPACTION */ - { - .procname = "min_free_kbytes", - .data = &min_free_kbytes, - .maxlen = sizeof(min_free_kbytes), - .mode = 0644, - .proc_handler = min_free_kbytes_sysctl_handler, - .extra1 = &zero, - }, - { - .procname = "percpu_pagelist_fraction", - .data = &percpu_pagelist_fraction, - .maxlen = sizeof(percpu_pagelist_fraction), - .mode = 0644, - .proc_handler = percpu_pagelist_fraction_sysctl_handler, - .extra1 = &min_percpu_pagelist_fract, - }, -#ifdef CONFIG_MMU - { - .procname = "max_map_count", - .data = &sysctl_max_map_count, - .maxlen = sizeof(sysctl_max_map_count), - .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = &zero, - }, -#else - { - .procname = "nr_trim_pages", - .data = &sysctl_nr_trim_pages, - .maxlen = sizeof(sysctl_nr_trim_pages), - .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = &zero, - }, -#endif - { - .procname = "laptop_mode", - .data = &laptop_mode, - .maxlen = sizeof(laptop_mode), - .mode = 0644, - .proc_handler = proc_dointvec_jiffies, - }, - { - .procname = "block_dump", - .data = &block_dump, - .maxlen = sizeof(block_dump), - .mode = 0644, - .proc_handler = proc_dointvec, - .extra1 = &zero, - }, - { - .procname = "vfs_cache_pressure", - .data = &sysctl_vfs_cache_pressure, - .maxlen = sizeof(sysctl_vfs_cache_pressure), - .mode = 0644, - .proc_handler = proc_dointvec, - .extra1 = &zero, - }, -#ifdef HAVE_ARCH_PICK_MMAP_LAYOUT - { - .procname = "legacy_va_layout", - .data = &sysctl_legacy_va_layout, - .maxlen = sizeof(sysctl_legacy_va_layout), - .mode = 0644, - .proc_handler = proc_dointvec, - .extra1 = &zero, - }, -#endif -#ifdef CONFIG_NUMA - { - .procname = "zone_reclaim_mode", - .data = &zone_reclaim_mode, - .maxlen = sizeof(zone_reclaim_mode), - .mode = 0644, - .proc_handler = proc_dointvec, - .extra1 = &zero, - }, - { - .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, - .extra1 = &zero, - .extra2 = &one_hundred, - }, - { - .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, - .extra1 = &zero, - .extra2 = &one_hundred, - }, -#endif -#ifdef CONFIG_SMP - { - .procname = "stat_interval", - .data = &sysctl_stat_interval, - .maxlen = sizeof(sysctl_stat_interval), - .mode = 0644, - .proc_handler = proc_dointvec_jiffies, - }, -#endif -#ifdef CONFIG_MMU - { - .procname = "mmap_min_addr", - .data = &dac_mmap_min_addr, - .maxlen = sizeof(unsigned long), - .mode = 0644, - .proc_handler = mmap_min_addr_handler, - }, -#endif -#ifdef CONFIG_NUMA - { - .procname = "numa_zonelist_order", - .data = &numa_zonelist_order, - .maxlen = NUMA_ZONELIST_ORDER_LEN, - .mode = 0644, - .proc_handler = numa_zonelist_order_handler, - }, -#endif -#if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \ - (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL)) - { - .procname = "vdso_enabled", - .data = &vdso_enabled, - .maxlen = sizeof(vdso_enabled), - .mode = 0644, - .proc_handler = proc_dointvec, - .extra1 = &zero, - }, -#endif -#ifdef CONFIG_HIGHMEM - { - .procname = "highmem_is_dirtyable", - .data = &vm_highmem_is_dirtyable, - .maxlen = sizeof(vm_highmem_is_dirtyable), - .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = &zero, - .extra2 = &one, - }, -#endif - { - .procname = "scan_unevictable_pages", - .data = &scan_unevictable_pages, - .maxlen = sizeof(scan_unevictable_pages), - .mode = 0644, - .proc_handler = scan_unevictable_handler, - }, -#ifdef CONFIG_MEMORY_FAILURE - { - .procname = "memory_failure_early_kill", - .data = &sysctl_memory_failure_early_kill, - .maxlen = sizeof(sysctl_memory_failure_early_kill), - .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = &zero, - .extra2 = &one, - }, - { - .procname = "memory_failure_recovery", - .data = &sysctl_memory_failure_recovery, - .maxlen = sizeof(sysctl_memory_failure_recovery), - .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = &zero, - .extra2 = &one, - }, -#endif - { - .procname = "user_reserve_kbytes", - .data = &sysctl_user_reserve_kbytes, - .maxlen = sizeof(sysctl_user_reserve_kbytes), - .mode = 0644, - .proc_handler = proc_doulongvec_minmax, - }, - { - .procname = "admin_reserve_kbytes", - .data = &sysctl_admin_reserve_kbytes, - .maxlen = sizeof(sysctl_admin_reserve_kbytes), - .mode = 0644, - .proc_handler = proc_doulongvec_minmax, - }, - { } -}; - -#if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE) -static struct ctl_table binfmt_misc_table[] = { - { } -}; -#endif - -static struct ctl_table fs_table[] = { - { - .procname = "inode-nr", - .data = &inodes_stat, - .maxlen = 2*sizeof(int), - .mode = 0444, - .proc_handler = proc_nr_inodes, - }, - { - .procname = "inode-state", - .data = &inodes_stat, - .maxlen = 7*sizeof(int), - .mode = 0444, - .proc_handler = proc_nr_inodes, - }, - { - .procname = "file-nr", - .data = &files_stat, - .maxlen = sizeof(files_stat), - .mode = 0444, - .proc_handler = proc_nr_files, - }, - { - .procname = "file-max", - .data = &files_stat.max_files, - .maxlen = sizeof(files_stat.max_files), - .mode = 0644, - .proc_handler = proc_doulongvec_minmax, - }, - { - .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, - }, - { - .procname = "dentry-state", - .data = &dentry_stat, - .maxlen = 6*sizeof(int), - .mode = 0444, - .proc_handler = proc_nr_dentry, - }, - { - .procname = "overflowuid", - .data = &fs_overflowuid, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = &minolduid, - .extra2 = &maxolduid, - }, - { - .procname = "overflowgid", - .data = &fs_overflowgid, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = &minolduid, - .extra2 = &maxolduid, - }, -#ifdef CONFIG_FILE_LOCKING - { - .procname = "leases-enable", - .data = &leases_enable, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, -#endif -#ifdef CONFIG_DNOTIFY - { - .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 - { - .procname = "lease-break-time", - .data = &lease_break_time, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, -#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 - { - .procname = "inotify", - .mode = 0555, - .child = inotify_table, - }, -#endif -#ifdef CONFIG_EPOLL - { - .procname = "epoll", - .mode = 0555, - .child = epoll_table, - }, -#endif -#endif - { - .procname = "protected_symlinks", - .data = &sysctl_protected_symlinks, - .maxlen = sizeof(int), - .mode = 0600, - .proc_handler = proc_dointvec_minmax, - .extra1 = &zero, - .extra2 = &one, - }, - { - .procname = "protected_hardlinks", - .data = &sysctl_protected_hardlinks, - .maxlen = sizeof(int), - .mode = 0600, - .proc_handler = proc_dointvec_minmax, - .extra1 = &zero, - .extra2 = &one, - }, - { - .procname = "suid_dumpable", - .data = &suid_dumpable, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec_minmax_coredump, - .extra1 = &zero, - .extra2 = &two, - }, -#if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE) - { - .procname = "binfmt_misc", - .mode = 0555, - .child = binfmt_misc_table, - }, -#endif - { - .procname = "pipe-max-size", - .data = &pipe_max_size, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = &pipe_proc_fn, - .extra1 = &pipe_min_size, - }, - { } -}; - -static struct ctl_table debug_table[] = { -#ifdef CONFIG_SYSCTL_EXCEPTION_TRACE - { - .procname = "exception-trace", - .data = &show_unhandled_signals, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec - }, -#endif -#if defined(CONFIG_OPTPROBES) - { - .procname = "kprobes-optimization", - .data = &sysctl_kprobes_optimization, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_kprobes_optimization_handler, - .extra1 = &zero, - .extra2 = &one, - }, -#endif - { } -}; - -static struct ctl_table dev_table[] = { - { } +/** + * enum sysctl_writes_mode - supported sysctl write modes + * + * @SYSCTL_WRITES_LEGACY: each write syscall must fully contain the sysctl value + * to be written, and multiple writes on the same sysctl file descriptor + * will rewrite the sysctl value, regardless of file position. No warning + * is issued when the initial position is not 0. + * @SYSCTL_WRITES_WARN: same as above but warn when the initial file position is + * not 0. + * @SYSCTL_WRITES_STRICT: writes to numeric sysctl entries must always be at + * file position 0 and the value must be fully contained in the buffer + * sent to the write syscall. If dealing with strings respect the file + * position, but restrict this to the max length of the buffer, anything + * passed the max length will be ignored. Multiple writes will append + * to the buffer. + * + * These write modes control how current file position affects the behavior of + * updating internal kernel (SYSCTL_USER_TO_KERN) sysctl values through the proc + * interface on each write. + */ +enum sysctl_writes_mode { + SYSCTL_WRITES_LEGACY = -1, + SYSCTL_WRITES_WARN = 0, + SYSCTL_WRITES_STRICT = 1, }; -int __init sysctl_init(void) -{ - struct ctl_table_header *hdr; - - hdr = register_sysctl_table(sysctl_base_table); - kmemleak_not_leak(hdr); - return 0; -} - +static enum sysctl_writes_mode sysctl_writes_strict = SYSCTL_WRITES_STRICT; +#endif /* CONFIG_PROC_SYSCTL */ #endif /* CONFIG_SYSCTL */ /* @@ -1679,35 +73,41 @@ int __init sysctl_init(void) #ifdef CONFIG_PROC_SYSCTL -static int _proc_do_string(void* data, int maxlen, int write, - void __user *buffer, - size_t *lenp, loff_t *ppos) +static int _proc_do_string(char *data, int maxlen, int dir, + char *buffer, size_t *lenp, loff_t *ppos) { size_t len; - char __user *p; - char c; + char c, *p; if (!data || !maxlen || !*lenp) { *lenp = 0; return 0; } - if (write) { - len = 0; + if (SYSCTL_USER_TO_KERN(dir)) { + if (sysctl_writes_strict == SYSCTL_WRITES_STRICT) { + /* Only continue writes not past the end of buffer. */ + len = strlen(data); + if (len > maxlen - 1) + len = maxlen - 1; + + if (*ppos > len) + return 0; + len = *ppos; + } else { + /* Start writing from beginning of buffer. */ + len = 0; + } + + *ppos += *lenp; p = buffer; - while (len < *lenp) { - if (get_user(c, p++)) - return -EFAULT; + while ((p - buffer) < *lenp && len < maxlen - 1) { + c = *(p++); if (c == 0 || c == '\n') break; - len++; + data[len++] = c; } - if (len >= maxlen) - len = maxlen-1; - if(copy_from_user(data, buffer, len)) - return -EFAULT; - ((char *) data)[len] = 0; - *ppos += *lenp; + data[len] = 0; } else { len = strlen(data); if (len > maxlen) @@ -1724,11 +124,9 @@ static int _proc_do_string(void* data, int maxlen, int write, if (len > *lenp) len = *lenp; if (len) - if(copy_to_user(buffer, data, len)) - return -EFAULT; + memcpy(buffer, data, len); if (len < *lenp) { - if(put_user('\n', ((char __user *) buffer) + len)) - return -EFAULT; + buffer[len] = '\n'; len++; } *lenp = len; @@ -1737,10 +135,44 @@ static int _proc_do_string(void* data, int maxlen, int write, return 0; } +static void warn_sysctl_write(const struct ctl_table *table) +{ + pr_warn_once("%s wrote to %s when file position was not 0!\n" + "This will not be supported in the future. To silence this\n" + "warning, set kernel.sysctl_writes_strict = -1\n", + current->comm, table->procname); +} + +/** + * proc_first_pos_non_zero_ignore - check if first position is allowed + * @ppos: file position + * @table: the sysctl table + * + * Returns true if the first position is non-zero and the sysctl_writes_strict + * mode indicates this is not allowed for numeric input types. String proc + * handlers can ignore the return value. + */ +static bool proc_first_pos_non_zero_ignore(loff_t *ppos, + const struct ctl_table *table) +{ + if (!*ppos) + return false; + + switch (sysctl_writes_strict) { + case SYSCTL_WRITES_STRICT: + return true; + case SYSCTL_WRITES_WARN: + warn_sysctl_write(table); + return false; + default: + return false; + } +} + /** * proc_dostring - read a string sysctl * @table: the sysctl table - * @write: %TRUE if this is a write to the sysctl file + * @dir: %TRUE if this is a write to the sysctl file * @buffer: the user buffer * @lenp: the size of the user buffer * @ppos: file position @@ -1754,20 +186,24 @@ static int _proc_do_string(void* data, int maxlen, int write, * * Returns 0 on success. */ -int proc_dostring(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos) +int proc_dostring(const struct ctl_table *table, int dir, + void *buffer, size_t *lenp, loff_t *ppos) { - return _proc_do_string(table->data, table->maxlen, write, - buffer, lenp, ppos); + if (SYSCTL_USER_TO_KERN(dir)) + proc_first_pos_non_zero_ignore(ppos, table); + + return _proc_do_string(table->data, table->maxlen, dir, buffer, lenp, + ppos); } -static size_t proc_skip_spaces(char **buf) +static void proc_skip_spaces(char **buf, size_t *size) { - size_t ret; - char *tmp = skip_spaces(*buf); - ret = tmp - *buf; - *buf = tmp; - return ret; + while (*size) { + if (!isspace(**buf)) + break; + (*size)--; + (*buf)++; + } } static void proc_skip_char(char **buf, size_t *size, const char v) @@ -1780,6 +216,41 @@ static void proc_skip_char(char **buf, size_t *size, const char v) } } +/** + * strtoul_lenient - parse an ASCII formatted integer from a buffer and only + * fail on overflow + * + * @cp: kernel buffer containing the string to parse + * @endp: pointer to store the trailing characters + * @base: the base to use + * @res: where the parsed integer will be stored + * + * In case of success 0 is returned and @res will contain the parsed integer, + * @endp will hold any trailing characters. + * This function will fail the parse on overflow. If there wasn't an overflow + * the function will defer the decision what characters count as invalid to the + * caller. + */ +static int strtoul_lenient(const char *cp, char **endp, unsigned int base, + unsigned long *res) +{ + unsigned long long result; + unsigned int rv; + + cp = _parse_integer_fixup_radix(cp, &base); + rv = _parse_integer(cp, base, &result); + if ((rv & KSTRTOX_OVERFLOW) || (result != (unsigned long)result)) + return -ERANGE; + + cp += rv; + + if (endp) + *endp = (char *)cp; + + *res = (unsigned long)result; + return 0; +} + #define TMPBUFLEN 22 /** * proc_get_long - reads an ASCII formatted integer from a user buffer @@ -1801,13 +272,12 @@ static int proc_get_long(char **buf, size_t *size, unsigned long *val, bool *neg, const char *perm_tr, unsigned perm_tr_len, char *tr) { - int len; char *p, tmp[TMPBUFLEN]; + ssize_t len = *size; - if (!*size) + if (len <= 0) return -EINVAL; - len = *size; if (len > TMPBUFLEN - 1) len = TMPBUFLEN - 1; @@ -1823,7 +293,8 @@ static int proc_get_long(char **buf, size_t *size, if (!isdigit(*p)) return -EINVAL; - *val = simple_strtoul(p, &p, 0); + if (strtoul_lenient(p, &p, 0, val)) + return -EINVAL; len = p - tmp; @@ -1853,11 +324,10 @@ static int proc_get_long(char **buf, size_t *size, * @val: the integer to be converted * @neg: sign of the number, %TRUE for negative * - * In case of success %0 is returned and @buf and @size are updated with - * the amount of bytes written. + * In case of success @buf and @size are updated with the amount of bytes + * written. */ -static int proc_put_long(void __user **buf, size_t *size, unsigned long val, - bool neg) +static void proc_put_long(void **buf, size_t *size, unsigned long val, bool neg) { int len; char tmp[TMPBUFLEN], *p = tmp; @@ -1866,242 +336,330 @@ static int proc_put_long(void __user **buf, size_t *size, unsigned long val, len = strlen(tmp); if (len > *size) len = *size; - if (copy_to_user(*buf, tmp, len)) - return -EFAULT; + memcpy(*buf, tmp, len); *size -= len; *buf += len; - return 0; } #undef TMPBUFLEN -static int proc_put_char(void __user **buf, size_t *size, char c) +static void proc_put_char(void **buf, size_t *size, char c) { if (*size) { - char __user **buffer = (char __user **)buf; - if (put_user(c, *buffer)) - return -EFAULT; - (*size)--, (*buffer)++; + char **buffer = (char **)buf; + **buffer = c; + + (*size)--; + (*buffer)++; *buf = *buffer; } - return 0; } -static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp, - int *valp, - int write, void *data) +static SYSCTL_USER_TO_KERN_INT_CONV(, SYSCTL_CONV_IDENTITY) +static SYSCTL_KERN_TO_USER_INT_CONV(, SYSCTL_CONV_IDENTITY) + +static SYSCTL_INT_CONV_CUSTOM(, sysctl_user_to_kern_int_conv, + sysctl_kern_to_user_int_conv, false) +static SYSCTL_INT_CONV_CUSTOM(_minmax, sysctl_user_to_kern_int_conv, + sysctl_kern_to_user_int_conv, true) + + +static SYSCTL_USER_TO_KERN_UINT_CONV(, SYSCTL_CONV_IDENTITY) + +int sysctl_kern_to_user_uint_conv(unsigned long *u_ptr, + const unsigned int *k_ptr) { - if (write) { - *valp = *negp ? -*lvalp : *lvalp; - } else { - int val = *valp; - if (val < 0) { - *negp = true; - *lvalp = (unsigned long)-val; - } else { - *negp = false; - *lvalp = (unsigned long)val; - } - } + unsigned int val = READ_ONCE(*k_ptr); + *u_ptr = (unsigned long)val; return 0; } +static SYSCTL_UINT_CONV_CUSTOM(, sysctl_user_to_kern_uint_conv, + sysctl_kern_to_user_uint_conv, false) +static SYSCTL_UINT_CONV_CUSTOM(_minmax, sysctl_user_to_kern_uint_conv, + sysctl_kern_to_user_uint_conv, true) + static const char proc_wspace_sep[] = { ' ', '\t', '\n' }; -static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table, - int write, void __user *buffer, - size_t *lenp, loff_t *ppos, - int (*conv)(bool *negp, unsigned long *lvalp, int *valp, - int write, void *data), - void *data) +static int do_proc_dointvec(const struct ctl_table *table, int dir, + void *buffer, size_t *lenp, loff_t *ppos, + int (*conv)(bool *negp, unsigned long *u_ptr, int *k_ptr, + int dir, const struct ctl_table *table)) { int *i, vleft, first = 1, err = 0; - unsigned long page = 0; size_t left; - char *kbuf; - - if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) { + char *p; + + if (!table->data || !table->maxlen || !*lenp || + (*ppos && SYSCTL_KERN_TO_USER(dir))) { *lenp = 0; return 0; } - - i = (int *) tbl_data; + + i = (int *) table->data; vleft = table->maxlen / sizeof(*i); left = *lenp; if (!conv) - conv = do_proc_dointvec_conv; + conv = do_proc_int_conv; + + if (SYSCTL_USER_TO_KERN(dir)) { + if (proc_first_pos_non_zero_ignore(ppos, table)) + goto out; - if (write) { if (left > PAGE_SIZE - 1) left = PAGE_SIZE - 1; - page = __get_free_page(GFP_TEMPORARY); - kbuf = (char *) page; - if (!kbuf) - return -ENOMEM; - if (copy_from_user(kbuf, buffer, left)) { - err = -EFAULT; - goto free; - } - kbuf[left] = 0; + p = buffer; } for (; left && vleft--; i++, first=0) { unsigned long lval; bool neg; - if (write) { - left -= proc_skip_spaces(&kbuf); + if (SYSCTL_USER_TO_KERN(dir)) { + proc_skip_spaces(&p, &left); if (!left) break; - err = proc_get_long(&kbuf, &left, &lval, &neg, + err = proc_get_long(&p, &left, &lval, &neg, proc_wspace_sep, sizeof(proc_wspace_sep), NULL); if (err) break; - if (conv(&neg, &lval, i, 1, data)) { + if (conv(&neg, &lval, i, 1, table)) { err = -EINVAL; break; } } else { - if (conv(&neg, &lval, i, 0, data)) { + if (conv(&neg, &lval, i, 0, table)) { err = -EINVAL; break; } if (!first) - err = proc_put_char(&buffer, &left, '\t'); - if (err) - break; - err = proc_put_long(&buffer, &left, lval, neg); - if (err) - break; + proc_put_char(&buffer, &left, '\t'); + proc_put_long(&buffer, &left, lval, neg); } } - if (!write && !first && left && !err) - err = proc_put_char(&buffer, &left, '\n'); - if (write && !err && left) - left -= proc_skip_spaces(&kbuf); -free: - if (write) { - free_page(page); - if (first) - return err ? : -EINVAL; + if (SYSCTL_KERN_TO_USER(dir) && !first && left && !err) + proc_put_char(&buffer, &left, '\n'); + if (SYSCTL_USER_TO_KERN(dir) && !err && left) + proc_skip_spaces(&p, &left); + if (SYSCTL_USER_TO_KERN(dir) && first) + return err ? : -EINVAL; + *lenp -= left; +out: + *ppos += *lenp; + return err; +} + +static int do_proc_douintvec_w(const struct ctl_table *table, void *buffer, + size_t *lenp, loff_t *ppos, + int (*conv)(unsigned long *u_ptr, + unsigned int *k_ptr, int dir, + const struct ctl_table *table)) +{ + unsigned long lval; + int err = 0; + size_t left; + bool neg; + char *p = buffer; + + left = *lenp; + + if (proc_first_pos_non_zero_ignore(ppos, table)) + goto bail_early; + + if (left > PAGE_SIZE - 1) + left = PAGE_SIZE - 1; + + proc_skip_spaces(&p, &left); + if (!left) { + err = -EINVAL; + goto out_free; + } + + err = proc_get_long(&p, &left, &lval, &neg, + proc_wspace_sep, + sizeof(proc_wspace_sep), NULL); + if (err || neg) { + err = -EINVAL; + goto out_free; } + + if (conv(&lval, (unsigned int *) table->data, 1, table)) { + err = -EINVAL; + goto out_free; + } + + if (!err && left) + proc_skip_spaces(&p, &left); + +out_free: + if (err) + return -EINVAL; + + return 0; + +bail_early: + *ppos += *lenp; + return err; +} + +static int do_proc_douintvec_r(const struct ctl_table *table, void *buffer, + size_t *lenp, loff_t *ppos, + int (*conv)(unsigned long *u_ptr, + unsigned int *k_ptr, int dir, + const struct ctl_table *table)) +{ + unsigned long lval; + int err = 0; + size_t left; + + left = *lenp; + + if (conv(&lval, (unsigned int *) table->data, 0, table)) { + err = -EINVAL; + goto out; + } + + proc_put_long(&buffer, &left, lval, false); + if (!left) + goto out; + + proc_put_char(&buffer, &left, '\n'); + +out: *lenp -= left; *ppos += *lenp; + return err; } -static int do_proc_dointvec(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos, - int (*conv)(bool *negp, unsigned long *lvalp, int *valp, - int write, void *data), - void *data) +static int do_proc_douintvec(const struct ctl_table *table, int dir, + void *buffer, size_t *lenp, loff_t *ppos, + int (*conv)(unsigned long *u_ptr, + unsigned int *k_ptr, int dir, + const struct ctl_table *table)) { - return __do_proc_dointvec(table->data, table, write, - buffer, lenp, ppos, conv, data); + unsigned int vleft; + + if (!table->data || !table->maxlen || !*lenp || + (*ppos && SYSCTL_KERN_TO_USER(dir))) { + *lenp = 0; + return 0; + } + + vleft = table->maxlen / sizeof(unsigned int); + + /* + * Arrays are not supported, keep this simple. *Do not* add + * support for them. + */ + if (vleft != 1) { + *lenp = 0; + return -EINVAL; + } + + if (!conv) + conv = do_proc_uint_conv; + + if (SYSCTL_USER_TO_KERN(dir)) + return do_proc_douintvec_w(table, buffer, lenp, ppos, conv); + return do_proc_douintvec_r(table, buffer, lenp, ppos, conv); } +int proc_douintvec_conv(const struct ctl_table *table, int dir, void *buffer, + size_t *lenp, loff_t *ppos, + int (*conv)(unsigned long *u_ptr, unsigned int *k_ptr, + int dir, const struct ctl_table *table)) +{ + return do_proc_douintvec(table, dir, buffer, lenp, ppos, conv); +} + + /** - * proc_dointvec - read a vector of integers + * proc_dobool - read/write a bool * @table: the sysctl table - * @write: %TRUE if this is a write to the sysctl file + * @dir: %TRUE if this is a write to the sysctl file * @buffer: the user buffer * @lenp: the size of the user buffer * @ppos: file position * - * Reads/writes up to table->maxlen/sizeof(unsigned int) integer - * values from/to the user buffer, treated as an ASCII string. + * Reads/writes one integer value from/to the user buffer, + * treated as an ASCII string. + * + * table->data must point to a bool variable and table->maxlen must + * be sizeof(bool). * * Returns 0 on success. */ -int proc_dointvec(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos) -{ - return do_proc_dointvec(table,write,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, - void __user *buffer, size_t *lenp, loff_t *ppos) +int proc_dobool(const struct ctl_table *table, int dir, void *buffer, + size_t *lenp, loff_t *ppos) { - struct ctl_table t; - unsigned long tmptaint = get_taint(); - int err; + struct ctl_table tmp; + bool *data = table->data; + int res, val; - if (write && !capable(CAP_SYS_ADMIN)) - return -EPERM; + /* Do not support arrays yet. */ + if (table->maxlen != sizeof(bool)) + return -EINVAL; - t = *table; - t.data = &tmptaint; - err = proc_doulongvec_minmax(&t, write, 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, LOCKDEP_STILL_OK); - } - } + tmp = *table; + tmp.maxlen = sizeof(val); + tmp.data = &val; - return err; + val = READ_ONCE(*data); + res = proc_dointvec(&tmp, dir, buffer, lenp, ppos); + if (res) + return res; + if (SYSCTL_USER_TO_KERN(dir)) + WRITE_ONCE(*data, val); + return 0; } -#ifdef CONFIG_PRINTK -static int proc_dointvec_minmax_sysadmin(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos) +/** + * proc_dointvec - read a vector of integers + * @table: the sysctl table + * @dir: %TRUE if this is a write to the sysctl file + * @buffer: the user buffer + * @lenp: the size of the user buffer + * @ppos: file position + * + * Reads/writes up to table->maxlen/sizeof(unsigned int) integer + * values from/to the user buffer, treated as an ASCII string. + * + * Returns 0 on success. + */ +int proc_dointvec(const struct ctl_table *table, int dir, void *buffer, + size_t *lenp, loff_t *ppos) { - if (write && !capable(CAP_SYS_ADMIN)) - return -EPERM; - - return proc_dointvec_minmax(table, write, buffer, lenp, ppos); + return do_proc_dointvec(table, dir, buffer, lenp, ppos, NULL); } -#endif -struct do_proc_dointvec_minmax_conv_param { - int *min; - int *max; -}; - -static int do_proc_dointvec_minmax_conv(bool *negp, unsigned long *lvalp, - int *valp, - int write, void *data) +/** + * proc_douintvec - read a vector of unsigned integers + * @table: the sysctl table + * @dir: %TRUE if this is a write to the sysctl file + * @buffer: the user buffer + * @lenp: the size of the user buffer + * @ppos: file position + * + * Reads/writes up to table->maxlen/sizeof(unsigned int) unsigned integer + * values from/to the user buffer, treated as an ASCII string. + * + * Returns 0 on success. + */ +int proc_douintvec(const struct ctl_table *table, int dir, void *buffer, + size_t *lenp, loff_t *ppos) { - 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 = true; - *lvalp = (unsigned long)-val; - } else { - *negp = false; - *lvalp = (unsigned long)val; - } - } - return 0; + return do_proc_douintvec(table, dir, buffer, lenp, ppos, + do_proc_uint_conv); } /** * 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 + * @dir: %TRUE if this is a write to the sysctl file * @buffer: the user buffer * @lenp: the size of the user buffer * @ppos: file position @@ -2112,145 +670,180 @@ static int do_proc_dointvec_minmax_conv(bool *negp, unsigned long *lvalp, * This routine will ensure the values are within the range specified by * table->extra1 (min) and table->extra2 (max). * - * Returns 0 on success. + * Returns 0 on success or -EINVAL when the range check fails and + * SYSCTL_USER_TO_KERN(dir) == true */ -int proc_dointvec_minmax(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos) +int proc_dointvec_minmax(const struct ctl_table *table, int dir, + void *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, buffer, lenp, ppos, - do_proc_dointvec_minmax_conv, ¶m); + return do_proc_dointvec(table, dir, buffer, lenp, ppos, + do_proc_int_conv_minmax); } -static void validate_coredump_safety(void) +/** + * proc_douintvec_minmax - read a vector of unsigned ints with min/max values + * @table: the sysctl table + * @dir: %TRUE if this is a write to the sysctl file + * @buffer: the user buffer + * @lenp: the size of the user buffer + * @ppos: file position + * + * Reads/writes up to table->maxlen/sizeof(unsigned int) unsigned integer + * values from/to the user buffer, treated as an ASCII string. Negative + * strings are not allowed. + * + * This routine will ensure the values are within the range specified by + * table->extra1 (min) and table->extra2 (max). There is a final sanity + * check for UINT_MAX to avoid having to support wrap around uses from + * userspace. + * + * Returns 0 on success or -ERANGE when range check failes and + * SYSCTL_USER_TO_KERN(dir) == true + */ +int proc_douintvec_minmax(const struct ctl_table *table, int dir, + void *buffer, size_t *lenp, loff_t *ppos) { -#ifdef CONFIG_COREDUMP - if (suid_dumpable == SUID_DUMP_ROOT && - core_pattern[0] != '/' && core_pattern[0] != '|') { - printk(KERN_WARNING "Unsafe core_pattern used with "\ - "suid_dumpable=2. Pipe handler or fully qualified "\ - "core dump path required.\n"); - } -#endif + return do_proc_douintvec(table, dir, buffer, lenp, ppos, + do_proc_uint_conv_minmax); } -static int proc_dointvec_minmax_coredump(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos) +/** + * proc_dou8vec_minmax - read a vector of unsigned chars with min/max values + * @table: the sysctl table + * @dir: %TRUE if this is a write to the sysctl file + * @buffer: the user buffer + * @lenp: the size of the user buffer + * @ppos: file position + * + * Reads/writes up to table->maxlen/sizeof(u8) unsigned chars + * values from/to the user buffer, treated as an ASCII string. Negative + * strings are not allowed. + * + * This routine will ensure the values are within the range specified by + * table->extra1 (min) and table->extra2 (max). + * + * Returns 0 on success or an error on SYSCTL_USER_TO_KERN(dir) == true + * and the range check fails. + */ +int proc_dou8vec_minmax(const struct ctl_table *table, int dir, + void *buffer, size_t *lenp, loff_t *ppos) { - int error = proc_dointvec_minmax(table, write, buffer, lenp, ppos); - if (!error) - validate_coredump_safety(); - return error; -} + struct ctl_table tmp; + unsigned int min = 0, max = 255U, val; + u8 *data = table->data; + int res; -#ifdef CONFIG_COREDUMP -static int proc_dostring_coredump(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos) -{ - int error = proc_dostring(table, write, buffer, lenp, ppos); - if (!error) - validate_coredump_safety(); - return error; + /* Do not support arrays yet. */ + if (table->maxlen != sizeof(u8)) + return -EINVAL; + + tmp = *table; + + tmp.maxlen = sizeof(val); + tmp.data = &val; + if (!tmp.extra1) + tmp.extra1 = (unsigned int *) &min; + if (!tmp.extra2) + tmp.extra2 = (unsigned int *) &max; + + val = READ_ONCE(*data); + res = do_proc_douintvec(&tmp, dir, buffer, lenp, ppos, + do_proc_uint_conv_minmax); + if (res) + return res; + if (SYSCTL_USER_TO_KERN(dir)) + WRITE_ONCE(*data, val); + return 0; } -#endif +EXPORT_SYMBOL_GPL(proc_dou8vec_minmax); -static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write, - void __user *buffer, - size_t *lenp, loff_t *ppos, +static int do_proc_doulongvec_minmax(const struct ctl_table *table, int dir, + void *buffer, size_t *lenp, loff_t *ppos, unsigned long convmul, unsigned long convdiv) { unsigned long *i, *min, *max; int vleft, first = 1, err = 0; - unsigned long page = 0; size_t left; - char *kbuf; + char *p; - if (!data || !table->maxlen || !*lenp || (*ppos && !write)) { + if (!table->data || !table->maxlen || !*lenp || + (*ppos && SYSCTL_KERN_TO_USER(dir))) { *lenp = 0; return 0; } - i = (unsigned long *) data; - min = (unsigned long *) table->extra1; - max = (unsigned long *) table->extra2; + i = table->data; + min = table->extra1; + max = table->extra2; vleft = table->maxlen / sizeof(unsigned long); left = *lenp; - if (write) { + if (SYSCTL_USER_TO_KERN(dir)) { + if (proc_first_pos_non_zero_ignore(ppos, table)) + goto out; + if (left > PAGE_SIZE - 1) left = PAGE_SIZE - 1; - page = __get_free_page(GFP_TEMPORARY); - kbuf = (char *) page; - if (!kbuf) - return -ENOMEM; - if (copy_from_user(kbuf, buffer, left)) { - err = -EFAULT; - goto free; - } - kbuf[left] = 0; + p = buffer; } for (; left && vleft--; i++, first = 0) { unsigned long val; - if (write) { + if (SYSCTL_USER_TO_KERN(dir)) { bool neg; - left -= proc_skip_spaces(&kbuf); + proc_skip_spaces(&p, &left); + if (!left) + break; - err = proc_get_long(&kbuf, &left, &val, &neg, + err = proc_get_long(&p, &left, &val, &neg, proc_wspace_sep, sizeof(proc_wspace_sep), NULL); - if (err) + if (err || neg) { + err = -EINVAL; + break; + } + + val = convmul * val / convdiv; + if ((min && val < *min) || (max && val > *max)) { + err = -EINVAL; break; - if (neg) - continue; - if ((min && val < *min) || (max && val > *max)) - continue; - *i = val; + } + WRITE_ONCE(*i, val); } else { - val = convdiv * (*i) / convmul; + val = convdiv * READ_ONCE(*i) / convmul; if (!first) - err = proc_put_char(&buffer, &left, '\t'); - err = proc_put_long(&buffer, &left, val, false); - if (err) - break; + proc_put_char(&buffer, &left, '\t'); + proc_put_long(&buffer, &left, val, false); } } - if (!write && !first && left && !err) - err = proc_put_char(&buffer, &left, '\n'); - if (write && !err) - left -= proc_skip_spaces(&kbuf); -free: - if (write) { - free_page(page); - if (first) - return err ? : -EINVAL; - } + if (SYSCTL_KERN_TO_USER(dir) && !first && left && !err) + proc_put_char(&buffer, &left, '\n'); + if (SYSCTL_USER_TO_KERN(dir) && !err) + proc_skip_spaces(&p, &left); + if (SYSCTL_USER_TO_KERN(dir) && first) + return err ? : -EINVAL; *lenp -= left; +out: *ppos += *lenp; return err; } -static int do_proc_doulongvec_minmax(struct ctl_table *table, int write, - void __user *buffer, - size_t *lenp, loff_t *ppos, - unsigned long convmul, - unsigned long convdiv) +int proc_doulongvec_minmax_conv(const struct ctl_table *table, int dir, + void *buffer, size_t *lenp, loff_t *ppos, + unsigned long convmul, unsigned long convdiv) { - return __do_proc_doulongvec_minmax(table->data, table, write, - buffer, lenp, ppos, convmul, convdiv); + return do_proc_doulongvec_minmax(table, dir, 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 + * @dir: %TRUE if this is a write to the sysctl file * @buffer: the user buffer * @lenp: the size of the user buffer * @ppos: file position @@ -2263,198 +856,24 @@ static int do_proc_doulongvec_minmax(struct ctl_table *table, int write, * * Returns 0 on success. */ -int proc_doulongvec_minmax(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos) -{ - return do_proc_doulongvec_minmax(table, write, 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 - * @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, - void __user *buffer, - size_t *lenp, loff_t *ppos) -{ - return do_proc_doulongvec_minmax(table, write, buffer, - lenp, ppos, HZ, 1000l); -} - - -static int do_proc_dointvec_jiffies_conv(bool *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 = true; - lval = (unsigned long)-val; - } else { - *negp = false; - lval = (unsigned long)val; - } - *lvalp = lval / HZ; - } - return 0; -} - -static int do_proc_dointvec_userhz_jiffies_conv(bool *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 = true; - lval = (unsigned long)-val; - } else { - *negp = false; - lval = (unsigned long)val; - } - *lvalp = jiffies_to_clock_t(lval); - } - return 0; -} - -static int do_proc_dointvec_ms_jiffies_conv(bool *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 = true; - lval = (unsigned long)-val; - } else { - *negp = false; - lval = (unsigned long)val; - } - *lvalp = jiffies_to_msecs(lval); - } - return 0; -} - -/** - * proc_dointvec_jiffies - read a vector of integers as seconds - * @table: the sysctl table - * @write: %TRUE if this is a write to the sysctl file - * @buffer: the user buffer - * @lenp: the size of the user buffer - * @ppos: file position - * - * Reads/writes up to table->maxlen/sizeof(unsigned int) integer - * values from/to the user buffer, treated as an ASCII string. - * The values read are assumed to be in seconds, and are converted into - * jiffies. - * - * Returns 0 on success. - */ -int proc_dointvec_jiffies(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos) -{ - return do_proc_dointvec(table,write,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 - * @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, - void __user *buffer, size_t *lenp, loff_t *ppos) +int proc_doulongvec_minmax(const struct ctl_table *table, int dir, + void *buffer, size_t *lenp, loff_t *ppos) { - return do_proc_dointvec(table,write,buffer,lenp,ppos, - do_proc_dointvec_userhz_jiffies_conv,NULL); + return proc_doulongvec_minmax_conv(table, dir, buffer, lenp, ppos, 1l, 1l); } -/** - * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds - * @table: the sysctl table - * @write: %TRUE if this is a write to the sysctl file - * @buffer: the user buffer - * @lenp: the size of the user buffer - * @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, - void __user *buffer, size_t *lenp, loff_t *ppos) +int proc_dointvec_conv(const struct ctl_table *table, int dir, void *buffer, + size_t *lenp, loff_t *ppos, + int (*conv)(bool *negp, unsigned long *u_ptr, int *k_ptr, + int dir, const struct ctl_table *table)) { - return do_proc_dointvec(table, write, buffer, lenp, ppos, - do_proc_dointvec_ms_jiffies_conv, NULL); -} - -static int proc_do_cad_pid(struct ctl_table *table, int write, - 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, 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; + return do_proc_dointvec(table, dir, buffer, lenp, ppos, conv); } /** * proc_do_large_bitmap - read/write from/to a large bitmap * @table: the sysctl table - * @write: %TRUE if this is a write to the sysctl file + * @dir: %TRUE if this is a write to the sysctl file * @buffer: the user buffer * @lenp: the size of the user buffer * @ppos: file position @@ -2468,52 +887,54 @@ static int proc_do_cad_pid(struct ctl_table *table, int write, * * Returns 0 on success. */ -int proc_do_large_bitmap(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos) +int proc_do_large_bitmap(const struct ctl_table *table, int dir, + void *buffer, size_t *lenp, loff_t *ppos) { int err = 0; - bool first = 1; size_t left = *lenp; unsigned long bitmap_len = table->maxlen; - unsigned long *bitmap = (unsigned long *) table->data; + unsigned long *bitmap = *(unsigned long **) table->data; unsigned long *tmp_bitmap = NULL; char tr_a[] = { '-', ',', '\n' }, tr_b[] = { ',', '\n', 0 }, c; - if (!bitmap_len || !left || (*ppos && !write)) { + if (!bitmap || !bitmap_len || !left || (*ppos && SYSCTL_KERN_TO_USER(dir))) { *lenp = 0; return 0; } - if (write) { - unsigned long page = 0; - char *kbuf; + if (SYSCTL_USER_TO_KERN(dir)) { + char *p = buffer; + size_t skipped = 0; - if (left > PAGE_SIZE - 1) + if (left > PAGE_SIZE - 1) { left = PAGE_SIZE - 1; + /* How much of the buffer we'll skip this pass */ + skipped = *lenp - left; + } - page = __get_free_page(GFP_TEMPORARY); - kbuf = (char *) page; - if (!kbuf) + tmp_bitmap = bitmap_zalloc(bitmap_len, GFP_KERNEL); + if (!tmp_bitmap) return -ENOMEM; - if (copy_from_user(kbuf, buffer, left)) { - free_page(page); - return -EFAULT; - } - kbuf[left] = 0; - - tmp_bitmap = kzalloc(BITS_TO_LONGS(bitmap_len) * sizeof(unsigned long), - GFP_KERNEL); - if (!tmp_bitmap) { - free_page(page); - return -ENOMEM; - } - proc_skip_char(&kbuf, &left, '\n'); + proc_skip_char(&p, &left, '\n'); while (!err && left) { unsigned long val_a, val_b; bool neg; + size_t saved_left; - err = proc_get_long(&kbuf, &left, &val_a, &neg, tr_a, + /* In case we stop parsing mid-number, we can reset */ + saved_left = left; + err = proc_get_long(&p, &left, &val_a, &neg, tr_a, sizeof(tr_a), &c); + /* + * If we consumed the entirety of a truncated buffer or + * only one char is left (may be a "-"), then stop here, + * reset, & come back for more. + */ + if ((left <= 1) && skipped) { + left = saved_left; + break; + } + if (err) break; if (val_a >= bitmap_len || neg) { @@ -2523,14 +944,23 @@ int proc_do_large_bitmap(struct ctl_table *table, int write, val_b = val_a; if (left) { - kbuf++; + p++; left--; } if (c == '-') { - err = proc_get_long(&kbuf, &left, &val_b, + err = proc_get_long(&p, &left, &val_b, &neg, tr_b, sizeof(tr_b), &c); + /* + * If we consumed all of a truncated buffer or + * then stop here, reset, & come back for more. + */ + if (!left && skipped) { + left = saved_left; + break; + } + if (err) break; if (val_b >= bitmap_len || neg || @@ -2539,18 +969,18 @@ int proc_do_large_bitmap(struct ctl_table *table, int write, break; } if (left) { - kbuf++; + p++; left--; } } bitmap_set(tmp_bitmap, val_a, val_b - val_a + 1); - first = 0; - proc_skip_char(&kbuf, &left, '\n'); + proc_skip_char(&p, &left, '\n'); } - free_page(page); + left += skipped; } else { unsigned long bit_a, bit_b = 0; + bool first = 1; while (left) { bit_a = find_next_bit(bitmap, bitmap_len, bit_b); @@ -2559,109 +989,200 @@ int proc_do_large_bitmap(struct ctl_table *table, int write, bit_b = find_next_zero_bit(bitmap, bitmap_len, bit_a + 1) - 1; - if (!first) { - err = proc_put_char(&buffer, &left, ','); - if (err) - break; - } - err = proc_put_long(&buffer, &left, bit_a, false); - if (err) - break; + if (!first) + proc_put_char(&buffer, &left, ','); + proc_put_long(&buffer, &left, bit_a, false); if (bit_a != bit_b) { - err = proc_put_char(&buffer, &left, '-'); - if (err) - break; - err = proc_put_long(&buffer, &left, bit_b, false); - if (err) - break; + proc_put_char(&buffer, &left, '-'); + proc_put_long(&buffer, &left, bit_b, false); } first = 0; bit_b++; } - if (!err) - err = proc_put_char(&buffer, &left, '\n'); + proc_put_char(&buffer, &left, '\n'); } if (!err) { - if (write) { + if (SYSCTL_USER_TO_KERN(dir)) { if (*ppos) bitmap_or(bitmap, bitmap, tmp_bitmap, bitmap_len); else bitmap_copy(bitmap, tmp_bitmap, bitmap_len); } - kfree(tmp_bitmap); *lenp -= left; *ppos += *lenp; - return 0; - } else { - kfree(tmp_bitmap); - return err; } + + bitmap_free(tmp_bitmap); + return err; } #else /* CONFIG_PROC_SYSCTL */ -int proc_dostring(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos) +int proc_dostring(const struct ctl_table *table, int dir, + void *buffer, size_t *lenp, loff_t *ppos) { return -ENOSYS; } -int proc_dointvec(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos) +int proc_dobool(const struct ctl_table *table, int dir, + void *buffer, size_t *lenp, loff_t *ppos) { return -ENOSYS; } -int proc_dointvec_minmax(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos) +int proc_dointvec(const struct ctl_table *table, int dir, + void *buffer, size_t *lenp, loff_t *ppos) { return -ENOSYS; } -int proc_dointvec_jiffies(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos) +int proc_douintvec(const struct ctl_table *table, int dir, + void *buffer, size_t *lenp, loff_t *ppos) { return -ENOSYS; } -int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos) +int proc_dointvec_minmax(const struct ctl_table *table, int dir, + void *buffer, size_t *lenp, loff_t *ppos) { return -ENOSYS; } -int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos) +int proc_douintvec_minmax(const struct ctl_table *table, int dir, + void *buffer, size_t *lenp, loff_t *ppos) { return -ENOSYS; } -int proc_doulongvec_minmax(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos) +int proc_dou8vec_minmax(const struct ctl_table *table, int dir, + void *buffer, size_t *lenp, loff_t *ppos) { return -ENOSYS; } -int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write, - void __user *buffer, - size_t *lenp, loff_t *ppos) +int proc_doulongvec_minmax(const struct ctl_table *table, int dir, + void *buffer, size_t *lenp, loff_t *ppos) { - return -ENOSYS; + return -ENOSYS; } +int proc_doulongvec_minmax_conv(const struct ctl_table *table, int dir, + void *buffer, size_t *lenp, loff_t *ppos, + unsigned long convmul, unsigned long convdiv) +{ + return -ENOSYS; +} + +int proc_dointvec_conv(const struct ctl_table *table, int dir, void *buffer, + size_t *lenp, loff_t *ppos, + int (*conv)(bool *negp, unsigned long *u_ptr, int *k_ptr, + int dir, const struct ctl_table *table)) +{ + return -ENOSYS; +} + +int proc_do_large_bitmap(const struct ctl_table *table, int dir, + void *buffer, size_t *lenp, loff_t *ppos) +{ + return -ENOSYS; +} #endif /* CONFIG_PROC_SYSCTL */ +#if defined(CONFIG_SYSCTL) +int proc_do_static_key(const struct ctl_table *table, int dir, + void *buffer, size_t *lenp, loff_t *ppos) +{ + struct static_key *key = (struct static_key *)table->data; + static DEFINE_MUTEX(static_key_mutex); + int val, ret; + struct ctl_table tmp = { + .data = &val, + .maxlen = sizeof(val), + .mode = table->mode, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_ONE, + }; + + if (SYSCTL_USER_TO_KERN(dir) && !capable(CAP_SYS_ADMIN)) + return -EPERM; + + mutex_lock(&static_key_mutex); + val = static_key_enabled(key); + ret = proc_dointvec_minmax(&tmp, dir, buffer, lenp, ppos); + if (SYSCTL_USER_TO_KERN(dir) && !ret) { + if (val) + static_key_enable(key); + else + static_key_disable(key); + } + mutex_unlock(&static_key_mutex); + return ret; +} + +static const struct ctl_table sysctl_subsys_table[] = { +#ifdef CONFIG_PROC_SYSCTL + { + .procname = "sysctl_writes_strict", + .data = &sysctl_writes_strict, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = SYSCTL_NEG_ONE, + .extra2 = SYSCTL_ONE, + }, +#endif + { + .procname = "ngroups_max", + .data = (void *)&ngroups_max, + .maxlen = sizeof (int), + .mode = 0444, + .proc_handler = proc_dointvec, + }, + { + .procname = "cap_last_cap", + .data = (void *)&cap_last_cap, + .maxlen = sizeof(int), + .mode = 0444, + .proc_handler = proc_dointvec, + }, +#ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW + { + .procname = "unaligned-trap", + .data = &unaligned_enabled, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec, + }, +#endif +#ifdef CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN + { + .procname = "ignore-unaligned-usertrap", + .data = &no_unaligned_warning, + .maxlen = sizeof (int), + .mode = 0644, + .proc_handler = proc_dointvec, + }, +#endif +}; + +int __init sysctl_init_bases(void) +{ + register_sysctl_init("kernel", sysctl_subsys_table); + + return 0; +} +#endif /* CONFIG_SYSCTL */ /* * No sense putting this after each symbol definition, twice, * exception granted :-) */ +EXPORT_SYMBOL(proc_dobool); EXPORT_SYMBOL(proc_dointvec); -EXPORT_SYMBOL(proc_dointvec_jiffies); +EXPORT_SYMBOL(proc_douintvec); EXPORT_SYMBOL(proc_dointvec_minmax); -EXPORT_SYMBOL(proc_dointvec_userhz_jiffies); -EXPORT_SYMBOL(proc_dointvec_ms_jiffies); +EXPORT_SYMBOL_GPL(proc_douintvec_minmax); EXPORT_SYMBOL(proc_dostring); EXPORT_SYMBOL(proc_doulongvec_minmax); -EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax); +EXPORT_SYMBOL(proc_do_large_bitmap); |