// SPDX-License-Identifier: GPL-2.0-only /* * sysctl.c: General linux system control interface */ #include <linux/sysctl.h> #include <linux/printk.h> #include <linux/capability.h> #include <linux/ratelimit.h> #include "internal.h" static const int ten_thousand = 10000; static int proc_dointvec_minmax_sysadmin(struct ctl_table *table, int write, 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); } static struct ctl_table printk_sysctls[] = { { .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 = SYSCTL_ZERO, .extra2 = (void *)&ten_thousand, }, { .procname = "printk_devkmsg", .data = devkmsg_log_str, .maxlen = DEVKMSG_STR_MAX_SIZE, .mode = 0644, .proc_handler = devkmsg_sysctl_set_loglvl, }, { .procname = "dmesg_restrict", .data = &dmesg_restrict, .maxlen = sizeof(int), .mode = 0644, .proc_handler = proc_dointvec_minmax_sysadmin, .extra1 = SYSCTL_ZERO, .extra2 = SYSCTL_ONE, }, { .procname = "kptr_restrict", .data = &kptr_restrict, .maxlen = sizeof(int), .mode = 0644, .proc_handler = proc_dointvec_minmax_sysadmin, .extra1 = SYSCTL_ZERO, .extra2 = SYSCTL_TWO, }, {} }; void __init printk_sysctl_init(void) { register_sysctl_init("kernel", printk_sysctls); }