diff options
Diffstat (limited to 'init/main.c')
| -rw-r--r-- | init/main.c | 1356 |
1 files changed, 1082 insertions, 274 deletions
diff --git a/init/main.c b/init/main.c index d03d2ec2eacf..b84818ad9685 100644 --- a/init/main.c +++ b/init/main.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * linux/init/main.c * @@ -6,14 +7,17 @@ * GK 2/5/95 - Changed to support mounting root fs via NFS * Added initrd & change_root: Werner Almesberger & Hans Lermen, Feb '96 * Moan early if gcc is old, avoiding bogus kernels - Paul Gortmaker, May '96 - * Simplified starting of init: Michael A. Griffith <grif@acm.org> + * Simplified starting of init: Michael A. Griffith <grif@acm.org> */ #define DEBUG /* Enable initcall_debug */ #include <linux/types.h> +#include <linux/export.h> +#include <linux/extable.h> #include <linux/module.h> #include <linux/proc_fs.h> +#include <linux/binfmts.h> #include <linux/kernel.h> #include <linux/syscalls.h> #include <linux/stackprotector.h> @@ -23,83 +27,96 @@ #include <linux/ioport.h> #include <linux/init.h> #include <linux/initrd.h> -#include <linux/bootmem.h> +#include <linux/memblock.h> #include <linux/acpi.h> -#include <linux/tty.h> +#include <linux/bootconfig.h> +#include <linux/console.h> +#include <linux/nmi.h> #include <linux/percpu.h> #include <linux/kmod.h> +#include <linux/kprobes.h> +#include <linux/kmsan.h> #include <linux/vmalloc.h> #include <linux/kernel_stat.h> #include <linux/start_kernel.h> #include <linux/security.h> #include <linux/smp.h> #include <linux/profile.h> +#include <linux/kfence.h> #include <linux/rcupdate.h> +#include <linux/srcu.h> #include <linux/moduleparam.h> #include <linux/kallsyms.h> +#include <linux/buildid.h> #include <linux/writeback.h> #include <linux/cpu.h> #include <linux/cpuset.h> +#include <linux/memcontrol.h> #include <linux/cgroup.h> -#include <linux/efi.h> #include <linux/tick.h> +#include <linux/sched/isolation.h> #include <linux/interrupt.h> #include <linux/taskstats_kern.h> #include <linux/delayacct.h> #include <linux/unistd.h> +#include <linux/utsname.h> #include <linux/rmap.h> #include <linux/mempolicy.h> #include <linux/key.h> -#include <linux/buffer_head.h> -#include <linux/page_cgroup.h> #include <linux/debug_locks.h> #include <linux/debugobjects.h> #include <linux/lockdep.h> #include <linux/kmemleak.h> +#include <linux/padata.h> #include <linux/pid_namespace.h> -#include <linux/device.h> +#include <linux/device/driver.h> #include <linux/kthread.h> #include <linux/sched.h> +#include <linux/sched/init.h> #include <linux/signal.h> #include <linux/idr.h> #include <linux/kgdb.h> #include <linux/ftrace.h> #include <linux/async.h> -#include <linux/kmemcheck.h> -#include <linux/sfi.h> #include <linux/shmem_fs.h> #include <linux/slab.h> #include <linux/perf_event.h> -#include <linux/file.h> #include <linux/ptrace.h> +#include <linux/pti.h> #include <linux/blkdev.h> -#include <linux/elevator.h> -#include <linux/sched_clock.h> +#include <linux/sched/clock.h> +#include <linux/sched/task.h> +#include <linux/sched/task_stack.h> +#include <linux/context_tracking.h> +#include <linux/random.h> +#include <linux/moduleloader.h> +#include <linux/list.h> +#include <linux/integrity.h> +#include <linux/proc_ns.h> +#include <linux/io.h> +#include <linux/cache.h> +#include <linux/rodata_test.h> +#include <linux/jump_label.h> +#include <linux/kcsan.h> +#include <linux/init_syscalls.h> +#include <linux/stackdepot.h> +#include <linux/randomize_kstack.h> +#include <linux/pidfs.h> +#include <linux/ptdump.h> +#include <linux/time_namespace.h> +#include <net/net_namespace.h> #include <asm/io.h> -#include <asm/bugs.h> #include <asm/setup.h> #include <asm/sections.h> #include <asm/cacheflush.h> -#ifdef CONFIG_X86_LOCAL_APIC -#include <asm/smp.h> -#endif - -static int kernel_init(void *); +#define CREATE_TRACE_POINTS +#include <trace/events/initcall.h> -extern void init_IRQ(void); -extern void fork_init(unsigned long); -extern void mca_init(void); -extern void sbus_init(void); -extern void radix_tree_init(void); -#ifndef CONFIG_DEBUG_RODATA -static inline void mark_rodata_ro(void) { } -#endif +#include <kunit/test.h> -#ifdef CONFIG_TC -extern void tc_init(void); -#endif +static int kernel_init(void *); /* * Debug helper: via this flag we know that we are in 'early bootup code' @@ -119,20 +136,39 @@ EXPORT_SYMBOL(system_state); #define MAX_INIT_ARGS CONFIG_INIT_ENV_ARG_LIMIT #define MAX_INIT_ENVS CONFIG_INIT_ENV_ARG_LIMIT -extern void time_init(void); /* Default late time init is NULL. archs can override this later. */ void (*__initdata late_time_init)(void); -extern void softirq_init(void); /* Untouched command line saved by arch-specific code. */ char __initdata boot_command_line[COMMAND_LINE_SIZE]; /* Untouched saved command line (eg. for /proc) */ -char *saved_command_line; +char *saved_command_line __ro_after_init; +unsigned int saved_command_line_len __ro_after_init; /* Command line for parameter parsing */ static char *static_command_line; +/* Untouched extra command line */ +static char *extra_command_line; +/* Extra init arguments */ +static char *extra_init_args; + +#ifdef CONFIG_BOOT_CONFIG +/* Is bootconfig on command line? */ +static bool bootconfig_found; +static size_t initargs_offs; +#else +# define bootconfig_found false +# define initargs_offs 0 +#endif static char *execute_command; -static char *ramdisk_execute_command; +static char *ramdisk_execute_command = "/init"; + +/* + * Used to generate warnings if static_key manipulation functions are used + * before jump_label_init is called. + */ +bool static_key_initialized __read_mostly; +EXPORT_SYMBOL_GPL(static_key_initialized); /* * If set, this is an indication to the drivers that reset the underlying @@ -140,7 +176,7 @@ static char *ramdisk_execute_command; * rely on the BIOS and skip the reset operation. * * This is useful if kernel is booting in an unreliable environment. - * For ex. kdump situaiton where previous kernel has crashed, BIOS has been + * For ex. kdump situation where previous kernel has crashed, BIOS has been * skipped and devices will be in unknown state. */ unsigned int reset_devices; @@ -154,16 +190,14 @@ static int __init set_reset_devices(char *str) __setup("reset_devices", set_reset_devices); -static const char * argv_init[MAX_INIT_ARGS+2] = { "init", NULL, }; -const char * envp_init[MAX_INIT_ENVS+2] = { "HOME=/", "TERM=linux", NULL, }; +static const char *argv_init[MAX_INIT_ARGS+2] = { "init", NULL, }; +const char *envp_init[MAX_INIT_ENVS+2] = { "HOME=/", "TERM=linux", NULL, }; static const char *panic_later, *panic_param; -extern const struct obs_kernel_param __setup_start[], __setup_end[]; - -static int __init obsolete_checksetup(char *line) +static bool __init obsolete_checksetup(char *line) { const struct obs_kernel_param *p; - int had_early_param = 0; + bool had_early_param = false; p = __setup_start; do { @@ -175,13 +209,13 @@ static int __init obsolete_checksetup(char *line) * Keep iterating, as we can have early * params and __setups of same names 8( */ if (line[n] == '\0' || line[n] == '=') - had_early_param = 1; + had_early_param = true; } else if (!p->setup_func) { pr_warn("Parameter %s is obsolete, ignored\n", p->str); - return 1; + return true; } else if (p->setup_func(line + n)) - return 1; + return true; } p++; } while (p < __setup_end); @@ -194,18 +228,17 @@ static int __init obsolete_checksetup(char *line) * still work even if initially too large, it will just take slightly longer */ unsigned long loops_per_jiffy = (1<<12); - EXPORT_SYMBOL(loops_per_jiffy); static int __init debug_kernel(char *str) { - console_loglevel = 10; + console_loglevel = CONSOLE_LOGLEVEL_DEBUG; return 0; } static int __init quiet_kernel(char *str) { - console_loglevel = 4; + console_loglevel = CONSOLE_LOGLEVEL_QUIET; return 0; } @@ -231,8 +264,244 @@ static int __init loglevel(char *str) early_param("loglevel", loglevel); +#ifdef CONFIG_BLK_DEV_INITRD +static void * __init get_boot_config_from_initrd(size_t *_size) +{ + u32 size, csum; + char *data; + u32 *hdr; + int i; + + if (!initrd_end) + return NULL; + + data = (char *)initrd_end - BOOTCONFIG_MAGIC_LEN; + /* + * Since Grub may align the size of initrd to 4, we must + * check the preceding 3 bytes as well. + */ + for (i = 0; i < 4; i++) { + if (!memcmp(data, BOOTCONFIG_MAGIC, BOOTCONFIG_MAGIC_LEN)) + goto found; + data--; + } + return NULL; + +found: + hdr = (u32 *)(data - 8); + size = le32_to_cpu(hdr[0]); + csum = le32_to_cpu(hdr[1]); + + data = ((void *)hdr) - size; + if ((unsigned long)data < initrd_start) { + pr_err("bootconfig size %d is greater than initrd size %ld\n", + size, initrd_end - initrd_start); + return NULL; + } + + if (xbc_calc_checksum(data, size) != csum) { + pr_err("bootconfig checksum failed\n"); + return NULL; + } + + /* Remove bootconfig from initramfs/initrd */ + initrd_end = (unsigned long)data; + if (_size) + *_size = size; + + return data; +} +#else +static void * __init get_boot_config_from_initrd(size_t *_size) +{ + return NULL; +} +#endif + +#ifdef CONFIG_BOOT_CONFIG + +static char xbc_namebuf[XBC_KEYLEN_MAX] __initdata; + +#define rest(dst, end) ((end) > (dst) ? (end) - (dst) : 0) + +static int __init xbc_snprint_cmdline(char *buf, size_t size, + struct xbc_node *root) +{ + struct xbc_node *knode, *vnode; + char *end = buf + size; + const char *val, *q; + int ret; + + xbc_node_for_each_key_value(root, knode, val) { + ret = xbc_node_compose_key_after(root, knode, + xbc_namebuf, XBC_KEYLEN_MAX); + if (ret < 0) + return ret; + + vnode = xbc_node_get_child(knode); + if (!vnode) { + ret = snprintf(buf, rest(buf, end), "%s ", xbc_namebuf); + if (ret < 0) + return ret; + buf += ret; + continue; + } + xbc_array_for_each_value(vnode, val) { + /* + * For prettier and more readable /proc/cmdline, only + * quote the value when necessary, i.e. when it contains + * whitespace. + */ + q = strpbrk(val, " \t\r\n") ? "\"" : ""; + ret = snprintf(buf, rest(buf, end), "%s=%s%s%s ", + xbc_namebuf, q, val, q); + if (ret < 0) + return ret; + buf += ret; + } + } + + return buf - (end - size); +} +#undef rest + +/* Make an extra command line under given key word */ +static char * __init xbc_make_cmdline(const char *key) +{ + struct xbc_node *root; + char *new_cmdline; + int ret, len = 0; + + root = xbc_find_node(key); + if (!root) + return NULL; + + /* Count required buffer size */ + len = xbc_snprint_cmdline(NULL, 0, root); + if (len <= 0) + return NULL; + + new_cmdline = memblock_alloc(len + 1, SMP_CACHE_BYTES); + if (!new_cmdline) { + pr_err("Failed to allocate memory for extra kernel cmdline.\n"); + return NULL; + } + + ret = xbc_snprint_cmdline(new_cmdline, len + 1, root); + if (ret < 0 || ret > len) { + pr_err("Failed to print extra kernel cmdline.\n"); + memblock_free(new_cmdline, len + 1); + return NULL; + } + + return new_cmdline; +} + +static int __init bootconfig_params(char *param, char *val, + const char *unused, void *arg) +{ + if (strcmp(param, "bootconfig") == 0) { + bootconfig_found = true; + } + return 0; +} + +static int __init warn_bootconfig(char *str) +{ + /* The 'bootconfig' has been handled by bootconfig_params(). */ + return 0; +} + +static void __init setup_boot_config(void) +{ + static char tmp_cmdline[COMMAND_LINE_SIZE] __initdata; + const char *msg, *data; + int pos, ret; + size_t size; + char *err; + + /* Cut out the bootconfig data even if we have no bootconfig option */ + data = get_boot_config_from_initrd(&size); + /* If there is no bootconfig in initrd, try embedded one. */ + if (!data) + data = xbc_get_embedded_bootconfig(&size); + + strscpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE); + err = parse_args("bootconfig", tmp_cmdline, NULL, 0, 0, 0, NULL, + bootconfig_params); + + if (IS_ERR(err) || !(bootconfig_found || IS_ENABLED(CONFIG_BOOT_CONFIG_FORCE))) + return; + + /* parse_args() stops at the next param of '--' and returns an address */ + if (err) + initargs_offs = err - tmp_cmdline; + + if (!data) { + /* If user intended to use bootconfig, show an error level message */ + if (bootconfig_found) + pr_err("'bootconfig' found on command line, but no bootconfig found\n"); + else + pr_info("No bootconfig data provided, so skipping bootconfig"); + return; + } + + if (size >= XBC_DATA_MAX) { + pr_err("bootconfig size %ld greater than max size %d\n", + (long)size, XBC_DATA_MAX); + return; + } + + ret = xbc_init(data, size, &msg, &pos); + if (ret < 0) { + if (pos < 0) + pr_err("Failed to init bootconfig: %s.\n", msg); + else + pr_err("Failed to parse bootconfig: %s at %d.\n", + msg, pos); + } else { + xbc_get_info(&ret, NULL); + pr_info("Load bootconfig: %ld bytes %d nodes\n", (long)size, ret); + /* keys starting with "kernel." are passed via cmdline */ + extra_command_line = xbc_make_cmdline("kernel"); + /* Also, "init." keys are init arguments */ + extra_init_args = xbc_make_cmdline("init"); + } + return; +} + +static void __init exit_boot_config(void) +{ + xbc_exit(); +} + +#else /* !CONFIG_BOOT_CONFIG */ + +static void __init setup_boot_config(void) +{ + /* Remove bootconfig data from initrd */ + get_boot_config_from_initrd(NULL); +} + +static int __init warn_bootconfig(char *str) +{ + pr_warn("WARNING: 'bootconfig' found on the kernel command line but CONFIG_BOOT_CONFIG is not set.\n"); + return 0; +} + +#define exit_boot_config() do {} while (0) + +#endif /* CONFIG_BOOT_CONFIG */ + +early_param("bootconfig", warn_bootconfig); + +bool __init cmdline_has_extra_options(void) +{ + return extra_command_line || extra_init_args; +} + /* Change NUL term back to "=", to make "param" the whole string. */ -static int __init repair_env_string(char *param, char *val, const char *unused) +static void __init repair_env_string(char *param, char *val) { if (val) { /* param=val or param="val"? */ @@ -241,10 +510,30 @@ static int __init repair_env_string(char *param, char *val, const char *unused) else if (val == param+strlen(param)+2) { val[-2] = '='; memmove(val-1, val, strlen(val)+1); - val--; } else BUG(); } +} + +/* Anything after -- gets handed straight to init. */ +static int __init set_init_arg(char *param, char *val, + const char *unused, void *arg) +{ + unsigned int i; + + if (panic_later) + return 0; + + repair_env_string(param, val); + + for (i = 0; argv_init[i]; i++) { + if (i == MAX_INIT_ARGS) { + panic_later = "init"; + panic_param = param; + return 0; + } + } + argv_init[i] = param; return 0; } @@ -252,16 +541,35 @@ static int __init repair_env_string(char *param, char *val, const char *unused) * Unknown boot options get handed to init, unless they look like * unused parameters (modprobe will find them in /proc/cmdline). */ -static int __init unknown_bootoption(char *param, char *val, const char *unused) +static int __init unknown_bootoption(char *param, char *val, + const char *unused, void *arg) { - repair_env_string(param, val, unused); + size_t len = strlen(param); + /* + * Well-known bootloader identifiers: + * 1. LILO/Grub pass "BOOT_IMAGE=..."; + * 2. kexec/kdump (kexec-tools) pass "kexec". + */ + const char *bootloader[] = { "BOOT_IMAGE=", "kexec", NULL }; + + /* Handle params aliased to sysctls */ + if (sysctl_is_alias(param)) + return 0; + + repair_env_string(param, val); + + /* Handle bootloader identifier */ + for (int i = 0; bootloader[i]; i++) { + if (strstarts(param, bootloader[i])) + return 0; + } /* Handle obsolete-style parameters */ if (obsolete_checksetup(param)) return 0; /* Unused module parameter. */ - if (strchr(param, '.') && (!val || strchr(param, '.') < val)) + if (strnchr(param, len, '.')) return 0; if (panic_later) @@ -272,10 +580,10 @@ static int __init unknown_bootoption(char *param, char *val, const char *unused) unsigned int i; for (i = 0; envp_init[i]; i++) { if (i == MAX_INIT_ENVS) { - panic_later = "Too many boot env vars at `%s'"; + panic_later = "env"; panic_param = param; } - if (!strncmp(param, envp_init[i], val - param)) + if (!strncmp(param, envp_init[i], len+1)) break; } envp_init[i] = param; @@ -284,7 +592,7 @@ static int __init unknown_bootoption(char *param, char *val, const char *unused) unsigned int i; for (i = 0; argv_init[i]; i++) { if (i == MAX_INIT_ARGS) { - panic_later = "Too many boot init vars at `%s'"; + panic_later = "init"; panic_param = param; } } @@ -323,16 +631,6 @@ static int __init rdinit_setup(char *str) __setup("rdinit=", rdinit_setup); #ifndef CONFIG_SMP -static const unsigned int setup_max_cpus = NR_CPUS; -#ifdef CONFIG_X86_LOCAL_APIC -static void __init smp_init(void) -{ - APIC_init_uniprocessor(); -} -#else -#define smp_init() do { } while (0) -#endif - static inline void setup_nr_cpu_ids(void) { } static inline void smp_prepare_cpus(unsigned int maxcpus) { } #endif @@ -345,10 +643,58 @@ static inline void smp_prepare_cpus(unsigned int maxcpus) { } */ static void __init setup_command_line(char *command_line) { - saved_command_line = alloc_bootmem(strlen (boot_command_line)+1); - static_command_line = alloc_bootmem(strlen (command_line)+1); - strcpy (saved_command_line, boot_command_line); - strcpy (static_command_line, command_line); + size_t len, xlen = 0, ilen = 0; + + if (extra_command_line) + xlen = strlen(extra_command_line); + if (extra_init_args) { + extra_init_args = strim(extra_init_args); /* remove trailing space */ + ilen = strlen(extra_init_args) + 4; /* for " -- " */ + } + + len = xlen + strlen(boot_command_line) + ilen + 1; + + saved_command_line = memblock_alloc_or_panic(len, SMP_CACHE_BYTES); + + len = xlen + strlen(command_line) + 1; + + static_command_line = memblock_alloc_or_panic(len, SMP_CACHE_BYTES); + + if (xlen) { + /* + * We have to put extra_command_line before boot command + * lines because there could be dashes (separator of init + * command line) in the command lines. + */ + strcpy(saved_command_line, extra_command_line); + strcpy(static_command_line, extra_command_line); + } + strcpy(saved_command_line + xlen, boot_command_line); + strcpy(static_command_line + xlen, command_line); + + if (ilen) { + /* + * Append supplemental init boot args to saved_command_line + * so that user can check what command line options passed + * to init. + * The order should always be + * " -- "[bootconfig init-param][cmdline init-param] + */ + if (initargs_offs) { + len = xlen + initargs_offs; + strcpy(saved_command_line + len, extra_init_args); + len += ilen - 4; /* strlen(extra_init_args) */ + strcpy(saved_command_line + len, + boot_command_line + initargs_offs - 1); + } else { + len = strlen(saved_command_line); + strcpy(saved_command_line + len, " -- "); + len += 4; + strcpy(saved_command_line + len, extra_init_args); + } + } + + saved_command_line_len = strlen(saved_command_line); } /* @@ -362,8 +708,9 @@ static void __init setup_command_line(char *command_line) static __initdata DECLARE_COMPLETION(kthreadd_done); -static noinline void __init_refok rest_init(void) +static noinline void __ref __noreturn rest_init(void) { + struct task_struct *tsk; int pid; rcu_scheduler_starting(); @@ -372,34 +719,52 @@ static noinline void __init_refok rest_init(void) * the init task will end up wanting to create kthreads, which, if * we schedule it before we create kthreadd, will OOPS. */ - kernel_thread(kernel_init, NULL, CLONE_FS | CLONE_SIGHAND); + pid = user_mode_thread(kernel_init, NULL, CLONE_FS); + /* + * Pin init on the boot CPU. Task migration is not properly working + * until sched_init_smp() has been run. It will set the allowed + * CPUs for init to the non isolated CPUs. + */ + rcu_read_lock(); + tsk = find_task_by_pid_ns(pid, &init_pid_ns); + tsk->flags |= PF_NO_SETAFFINITY; + set_cpus_allowed_ptr(tsk, cpumask_of(smp_processor_id())); + rcu_read_unlock(); + numa_default_policy(); - pid = kernel_thread(kthreadd, NULL, CLONE_FS | CLONE_FILES); + pid = kernel_thread(kthreadd, NULL, NULL, CLONE_FS | CLONE_FILES); rcu_read_lock(); kthreadd_task = find_task_by_pid_ns(pid, &init_pid_ns); rcu_read_unlock(); + + /* + * Enable might_sleep() and smp_processor_id() checks. + * They cannot be enabled earlier because with CONFIG_PREEMPTION=y + * kernel_thread() would trigger might_sleep() splats. With + * CONFIG_PREEMPT_VOLUNTARY=y the init task might have scheduled + * already, but it's stuck on the kthreadd_done completion. + */ + system_state = SYSTEM_SCHEDULING; + complete(&kthreadd_done); /* * The boot idle thread must execute schedule() * at least once to get things moving: */ - init_idle_bootup_task(current); schedule_preempt_disabled(); /* Call into cpu_idle with preempt disabled */ cpu_startup_entry(CPUHP_ONLINE); } /* Check for early params. */ -static int __init do_early_param(char *param, char *val, const char *unused) +static int __init do_early_param(char *param, char *val, + const char *unused, void *arg) { const struct obs_kernel_param *p; for (p = __setup_start; p < __setup_end; p++) { - if ((p->early && parameq(param, p->str)) || - (strcmp(param, "console") == 0 && - strcmp(p->str, "earlycon") == 0) - ) { + if (p->early && parameq(param, p->str)) { if (p->setup_func(val) != 0) pr_warn("Malformed early option '%s'\n", param); } @@ -410,124 +775,301 @@ static int __init do_early_param(char *param, char *val, const char *unused) void __init parse_early_options(char *cmdline) { - parse_args("early options", cmdline, NULL, 0, 0, 0, do_early_param); + parse_args("early options", cmdline, NULL, 0, 0, 0, NULL, + do_early_param); } /* Arch code calls this early on, or if not, just before other parsing. */ void __init parse_early_param(void) { - static __initdata int done = 0; - static __initdata char tmp_cmdline[COMMAND_LINE_SIZE]; + static int done __initdata; + static char tmp_cmdline[COMMAND_LINE_SIZE] __initdata; if (done) return; /* All fall through to do_early_param. */ - strlcpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE); + strscpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE); parse_early_options(tmp_cmdline); done = 1; } -/* - * Activate the first processor. - */ +void __init __weak arch_post_acpi_subsys_init(void) { } -static void __init boot_cpu_init(void) +void __init __weak smp_setup_processor_id(void) { - int cpu = smp_processor_id(); - /* Mark the boot cpu "present", "online" etc for SMP and UP case */ - set_cpu_online(cpu, true); - set_cpu_active(cpu, true); - set_cpu_present(cpu, true); - set_cpu_possible(cpu, true); } -void __init __weak smp_setup_processor_id(void) +void __init __weak smp_prepare_boot_cpu(void) { } # if THREAD_SIZE >= PAGE_SIZE -void __init __weak thread_info_cache_init(void) +void __init __weak thread_stack_cache_init(void) { } #endif -/* - * Set up kernel memory allocators - */ -static void __init mm_init(void) +void __init __weak poking_init(void) { } + +void __init __weak pgtable_cache_init(void) { } + +void __init __weak trap_init(void) { } + +bool initcall_debug; +core_param(initcall_debug, initcall_debug, bool, 0644); + +#ifdef TRACEPOINTS_ENABLED +static void __init initcall_debug_enable(void); +#else +static inline void initcall_debug_enable(void) { - /* - * page_cgroup requires contiguous pages, - * bigger than MAX_ORDER unless SPARSEMEM. - */ - page_cgroup_init_flatmem(); - mem_init(); - kmem_cache_init(); - percpu_init_late(); - pgtable_cache_init(); - vmalloc_init(); } +#endif -asmlinkage void __init start_kernel(void) +#ifdef CONFIG_RANDOMIZE_KSTACK_OFFSET +DEFINE_STATIC_KEY_MAYBE_RO(CONFIG_RANDOMIZE_KSTACK_OFFSET_DEFAULT, + randomize_kstack_offset); +DEFINE_PER_CPU(u32, kstack_offset); + +static int __init early_randomize_kstack_offset(char *buf) { - char * command_line; - extern const struct kernel_param __start___param[], __stop___param[]; + int ret; + bool bool_result; + + ret = kstrtobool(buf, &bool_result); + if (ret) + return ret; + + if (bool_result) + static_branch_enable(&randomize_kstack_offset); + else + static_branch_disable(&randomize_kstack_offset); + return 0; +} +early_param("randomize_kstack_offset", early_randomize_kstack_offset); +#endif + +static void __init print_unknown_bootoptions(void) +{ + char *unknown_options; + char *end; + const char *const *p; + size_t len; + + if (panic_later || (!argv_init[1] && !envp_init[2])) + return; /* - * Need to run as early as possible, to initialize the - * lockdep hash: + * Determine how many options we have to print out, plus a space + * before each */ - lockdep_init(); + len = 1; /* null terminator */ + for (p = &argv_init[1]; *p; p++) { + len++; + len += strlen(*p); + } + for (p = &envp_init[2]; *p; p++) { + len++; + len += strlen(*p); + } + + unknown_options = memblock_alloc(len, SMP_CACHE_BYTES); + if (!unknown_options) { + pr_err("%s: Failed to allocate %zu bytes\n", + __func__, len); + return; + } + end = unknown_options; + + for (p = &argv_init[1]; *p; p++) + end += sprintf(end, " %s", *p); + for (p = &envp_init[2]; *p; p++) + end += sprintf(end, " %s", *p); + + /* Start at unknown_options[1] to skip the initial space */ + pr_notice("Unknown kernel command line parameters \"%s\", will be passed to user space.\n", + &unknown_options[1]); + memblock_free(unknown_options, len); +} + +static void __init early_numa_node_init(void) +{ +#ifdef CONFIG_USE_PERCPU_NUMA_NODE_ID +#ifndef cpu_to_node + int cpu; + + /* The early_cpu_to_node() should be ready here. */ + for_each_possible_cpu(cpu) + set_cpu_numa_node(cpu, early_cpu_to_node(cpu)); +#endif +#endif +} + +#define KERNEL_CMDLINE_PREFIX "Kernel command line: " +#define KERNEL_CMDLINE_PREFIX_LEN (sizeof(KERNEL_CMDLINE_PREFIX) - 1) +#define KERNEL_CMDLINE_CONTINUATION " \\" +#define KERNEL_CMDLINE_CONTINUATION_LEN (sizeof(KERNEL_CMDLINE_CONTINUATION) - 1) + +#define MIN_CMDLINE_LOG_WRAP_IDEAL_LEN (KERNEL_CMDLINE_PREFIX_LEN + \ + KERNEL_CMDLINE_CONTINUATION_LEN) +#define CMDLINE_LOG_WRAP_IDEAL_LEN (CONFIG_CMDLINE_LOG_WRAP_IDEAL_LEN > \ + MIN_CMDLINE_LOG_WRAP_IDEAL_LEN ? \ + CONFIG_CMDLINE_LOG_WRAP_IDEAL_LEN : \ + MIN_CMDLINE_LOG_WRAP_IDEAL_LEN) + +#define IDEAL_CMDLINE_LEN (CMDLINE_LOG_WRAP_IDEAL_LEN - KERNEL_CMDLINE_PREFIX_LEN) +#define IDEAL_CMDLINE_SPLIT_LEN (IDEAL_CMDLINE_LEN - KERNEL_CMDLINE_CONTINUATION_LEN) + +/** + * print_kernel_cmdline() - Print the kernel cmdline with wrapping. + * @cmdline: The cmdline to print. + * + * Print the kernel command line, trying to wrap based on the Kconfig knob + * CONFIG_CMDLINE_LOG_WRAP_IDEAL_LEN. + * + * Wrapping is based on spaces, ignoring quotes. All lines are prefixed + * with "Kernel command line: " and lines that are not the last line have + * a " \" suffix added to them. The prefix and suffix count towards the + * line length for wrapping purposes. The ideal length will be exceeded + * if no appropriate place to wrap is found. + * + * Example output if CONFIG_CMDLINE_LOG_WRAP_IDEAL_LEN is 40: + * Kernel command line: loglevel=7 \ + * Kernel command line: init=/sbin/init \ + * Kernel command line: root=PARTUUID=8c3efc1a-768b-6642-8d0c-89eb782f19f0/PARTNROFF=1 \ + * Kernel command line: rootwait ro \ + * Kernel command line: my_quoted_arg="The \ + * Kernel command line: quick brown fox \ + * Kernel command line: jumps over the \ + * Kernel command line: lazy dog." + */ +static void __init print_kernel_cmdline(const char *cmdline) +{ + size_t len; + + /* Config option of 0 or anything longer than the max disables wrapping */ + if (CONFIG_CMDLINE_LOG_WRAP_IDEAL_LEN == 0 || + IDEAL_CMDLINE_LEN >= COMMAND_LINE_SIZE - 1) { + pr_notice("%s%s\n", KERNEL_CMDLINE_PREFIX, cmdline); + return; + } + + len = strlen(cmdline); + while (len > IDEAL_CMDLINE_LEN) { + const char *first_space; + const char *prev_cutoff; + const char *cutoff; + int to_print; + size_t used; + + /* Find the last ' ' that wouldn't make the line too long */ + prev_cutoff = NULL; + cutoff = cmdline; + while (true) { + cutoff = strchr(cutoff + 1, ' '); + if (!cutoff || cutoff - cmdline > IDEAL_CMDLINE_SPLIT_LEN) + break; + prev_cutoff = cutoff; + } + if (prev_cutoff) + cutoff = prev_cutoff; + else if (!cutoff) + break; + + /* Find the beginning and end of the string of spaces */ + first_space = cutoff; + while (first_space > cmdline && first_space[-1] == ' ') + first_space--; + to_print = first_space - cmdline; + while (*cutoff == ' ') + cutoff++; + used = cutoff - cmdline; + + /* If the whole string is used, break and do the final printout */ + if (len == used) + break; + + if (to_print) + pr_notice("%s%.*s%s\n", KERNEL_CMDLINE_PREFIX, + to_print, cmdline, KERNEL_CMDLINE_CONTINUATION); + + len -= used; + cmdline += used; + } + if (len) + pr_notice("%s%s\n", KERNEL_CMDLINE_PREFIX, cmdline); +} + +asmlinkage __visible __init __no_sanitize_address __noreturn __no_stack_protector +void start_kernel(void) +{ + char *command_line; + char *after_dashes; + + set_task_stack_end_magic(&init_task); smp_setup_processor_id(); debug_objects_early_init(); - - /* - * Set up the the initial canary ASAP: - */ - boot_init_stack_canary(); + init_vmlinux_build_id(); cgroup_init_early(); local_irq_disable(); early_boot_irqs_disabled = true; -/* - * Interrupts are still disabled. Do necessary setups, then - * enable them - */ + /* + * Interrupts are still disabled. Do necessary setups, then + * enable them. + */ boot_cpu_init(); page_address_init(); pr_notice("%s", linux_banner); setup_arch(&command_line); - mm_init_owner(&init_mm, &init_task); - mm_init_cpumask(&init_mm); + /* Static keys and static calls are needed by LSMs */ + jump_label_init(); + static_call_init(); + early_security_init(); + setup_boot_config(); setup_command_line(command_line); setup_nr_cpu_ids(); setup_per_cpu_areas(); smp_prepare_boot_cpu(); /* arch-specific boot-cpu hooks */ + early_numa_node_init(); + boot_cpu_hotplug_init(); - build_all_zonelists(NULL, NULL); - page_alloc_init(); - - pr_notice("Kernel command line: %s\n", boot_command_line); + print_kernel_cmdline(saved_command_line); + /* parameters may set static keys */ parse_early_param(); - parse_args("Booting kernel", static_command_line, __start___param, - __stop___param - __start___param, - -1, -1, &unknown_bootoption); - - jump_label_init(); + after_dashes = parse_args("Booting kernel", + static_command_line, __start___param, + __stop___param - __start___param, + -1, -1, NULL, &unknown_bootoption); + print_unknown_bootoptions(); + if (!IS_ERR_OR_NULL(after_dashes)) + parse_args("Setting init args", after_dashes, NULL, 0, -1, -1, + NULL, set_init_arg); + if (extra_init_args) + parse_args("Setting extra init args", extra_init_args, + NULL, 0, -1, -1, NULL, set_init_arg); + + /* Architectural and non-timekeeping rng init, before allocator init */ + random_init_early(command_line); /* * These use large bootmem allocations and must precede - * kmem_cache_init() + * initalization of page allocator */ setup_log_buf(0); - pidhash_init(); vfs_caches_init_early(); sort_main_extable(); trap_init(); - mm_init(); + mm_core_init(); + maple_tree_init(); + poking_init(); + ftrace_init(); + + /* trace_printk can be enabled here */ + early_trace_init(); /* * Set up the scheduler prior starting any interrupts (such as the @@ -535,31 +1077,59 @@ asmlinkage void __init start_kernel(void) * time - but meanwhile we still have a functioning scheduler. */ sched_init(); + + if (WARN(!irqs_disabled(), + "Interrupts were enabled *very* early, fixing it\n")) + local_irq_disable(); + radix_tree_init(); + /* - * Disable preemption - early bootup scheduling is extremely - * fragile until we cpu_idle() for the first time. + * Set up housekeeping before setting up workqueues to allow the unbound + * workqueue to take non-housekeeping into account. */ - preempt_disable(); - if (WARN(!irqs_disabled(), "Interrupts were enabled *very* early, fixing it\n")) - local_irq_disable(); - idr_init_cache(); + housekeeping_init(); + + /* + * Allow workqueue creation and work item queueing/cancelling + * early. Work item execution depends on kthreads and starts after + * workqueue_init(). + */ + workqueue_init_early(); + rcu_init(); - tick_nohz_init(); - radix_tree_init(); + kvfree_rcu_init(); + + /* Trace events are available after this */ + trace_init(); + + if (initcall_debug) + initcall_debug_enable(); + + context_tracking_init(); /* init some links before init_ISA_irqs() */ early_irq_init(); init_IRQ(); tick_init(); - init_timers(); + rcu_init_nohz(); + timers_init(); + srcu_init(); hrtimers_init(); softirq_init(); timekeeping_init(); time_init(); - sched_clock_postinit(); + + /* This must be after timekeeping is initialized */ + random_init(); + + /* These make use of the fully initialized rng */ + kfence_init(); + boot_init_stack_canary(); + perf_event_init(); profile_init(); call_function_init(); WARN(!irqs_disabled(), "Interrupts were enabled early\n"); + early_boot_irqs_disabled = false; local_irq_enable(); @@ -572,9 +1142,10 @@ asmlinkage void __init start_kernel(void) */ console_init(); if (panic_later) - panic(panic_later, panic_param); + panic("Too many boot %s vars at `%s'", panic_later, + panic_param); - lockdep_info(); + lockdep_init(); /* * Need to run this when irqs are enabled, because it wants @@ -592,61 +1163,67 @@ asmlinkage void __init start_kernel(void) initrd_start = 0; } #endif - page_cgroup_init(); - debug_objects_mem_init(); - kmemleak_init(); setup_per_cpu_pageset(); numa_policy_init(); + acpi_early_init(); if (late_time_init) late_time_init(); sched_clock_init(); calibrate_delay(); - pidmap_init(); + + arch_cpu_finalize_init(); + + pid_idr_init(); anon_vma_init(); -#ifdef CONFIG_X86 - if (efi_enabled(EFI_RUNTIME_SERVICES)) - efi_enter_virtual_mode(); -#endif - thread_info_cache_init(); + thread_stack_cache_init(); cred_init(); - fork_init(totalram_pages); + fork_init(); proc_caches_init(); - buffer_init(); + uts_ns_init(); + time_ns_init(); key_init(); security_init(); dbg_late_init(); - vfs_caches_init(totalram_pages); + net_ns_init(); + vfs_caches_init(); + pagecache_init(); signals_init(); - /* rootfs populating might need page-writeback */ - page_writeback_init(); -#ifdef CONFIG_PROC_FS + seq_file_init(); proc_root_init(); -#endif - cgroup_init(); + nsfs_init(); + pidfs_init(); cpuset_init(); + mem_cgroup_init(); + cgroup_init(); taskstats_init_early(); delayacct_init(); - check_bugs(); - - acpi_early_init(); /* before LAPIC and SMP init */ - sfi_init_late(); - - if (efi_enabled(EFI_RUNTIME_SERVICES)) { - efi_late_init(); - efi_free_boot_services(); - } - - ftrace_init(); + acpi_subsystem_init(); + arch_post_acpi_subsys_init(); + kcsan_init(); /* Do the rest non-__init'ed, we're now alive */ rest_init(); + + /* + * Avoid stack canaries in callers of boot_init_stack_canary for gcc-10 + * and older. + */ +#if !__has_attribute(__no_stack_protector__) + prevent_tail_call_optimization(); +#endif } /* Call all constructor functions linked into the kernel. */ static void __init do_ctors(void) { -#ifdef CONFIG_CONSTRUCTORS +/* + * For UML, the constructors have already been called by the + * normal setup code as it's just a normal ELF binary, so we + * cannot do it again - but we do need CONFIG_CONSTRUCTORS + * even on UML for modules. + */ +#if defined(CONFIG_CONSTRUCTORS) && !defined(CONFIG_UML) ctor_fn_t *fn = (ctor_fn_t *) __ctors_start; for (; fn < (ctor_fn_t *) __ctors_end; fn++) @@ -654,66 +1231,171 @@ static void __init do_ctors(void) #endif } -bool initcall_debug; -core_param(initcall_debug, initcall_debug, bool, 0644); +#ifdef CONFIG_KALLSYMS +struct blacklist_entry { + struct list_head next; + char *buf; +}; + +static __initdata_or_module LIST_HEAD(blacklisted_initcalls); -static int __init_or_module do_one_initcall_debug(initcall_t fn) +static int __init initcall_blacklist(char *str) { - ktime_t calltime, delta, rettime; - unsigned long long duration; - int ret; + char *str_entry; + struct blacklist_entry *entry; + + /* str argument is a comma-separated list of functions */ + do { + str_entry = strsep(&str, ","); + if (str_entry) { + pr_debug("blacklisting initcall %s\n", str_entry); + entry = memblock_alloc_or_panic(sizeof(*entry), + SMP_CACHE_BYTES); + entry->buf = memblock_alloc_or_panic(strlen(str_entry) + 1, + SMP_CACHE_BYTES); + strcpy(entry->buf, str_entry); + list_add(&entry->next, &blacklisted_initcalls); + } + } while (str_entry); + + return 1; +} + +static bool __init_or_module initcall_blacklisted(initcall_t fn) +{ + struct blacklist_entry *entry; + char fn_name[KSYM_SYMBOL_LEN]; + unsigned long addr; + + if (list_empty(&blacklisted_initcalls)) + return false; + + addr = (unsigned long) dereference_function_descriptor(fn); + sprint_symbol_no_offset(fn_name, addr); + + /* + * fn will be "function_name [module_name]" where [module_name] is not + * displayed for built-in init functions. Strip off the [module_name]. + */ + strreplace(fn_name, ' ', '\0'); + + list_for_each_entry(entry, &blacklisted_initcalls, next) { + if (!strcmp(fn_name, entry->buf)) { + pr_debug("initcall %s blacklisted\n", fn_name); + return true; + } + } + + return false; +} +#else +static int __init initcall_blacklist(char *str) +{ + pr_warn("initcall_blacklist requires CONFIG_KALLSYMS\n"); + return 0; +} + +static bool __init_or_module initcall_blacklisted(initcall_t fn) +{ + return false; +} +#endif +__setup("initcall_blacklist=", initcall_blacklist); + +static __init_or_module void +trace_initcall_start_cb(void *data, initcall_t fn) +{ + ktime_t *calltime = data; + + printk(KERN_DEBUG "calling %pS @ %i\n", fn, task_pid_nr(current)); + *calltime = ktime_get(); +} + +static __init_or_module void +trace_initcall_finish_cb(void *data, initcall_t fn, int ret) +{ + ktime_t rettime, *calltime = data; - pr_debug("calling %pF @ %i\n", fn, task_pid_nr(current)); - calltime = ktime_get(); - ret = fn(); rettime = ktime_get(); - delta = ktime_sub(rettime, calltime); - duration = (unsigned long long) ktime_to_ns(delta) >> 10; - pr_debug("initcall %pF returned %d after %lld usecs\n", - fn, ret, duration); + printk(KERN_DEBUG "initcall %pS returned %d after %lld usecs\n", + fn, ret, (unsigned long long)ktime_us_delta(rettime, *calltime)); +} - return ret; +static __init_or_module void +trace_initcall_level_cb(void *data, const char *level) +{ + printk(KERN_DEBUG "entering initcall level: %s\n", level); +} + +static ktime_t initcall_calltime; + +#ifdef TRACEPOINTS_ENABLED +static void __init initcall_debug_enable(void) +{ + int ret; + + ret = register_trace_initcall_start(trace_initcall_start_cb, + &initcall_calltime); + ret |= register_trace_initcall_finish(trace_initcall_finish_cb, + &initcall_calltime); + ret |= register_trace_initcall_level(trace_initcall_level_cb, NULL); + WARN(ret, "Failed to register initcall tracepoints\n"); +} +# define do_trace_initcall_start trace_initcall_start +# define do_trace_initcall_finish trace_initcall_finish +# define do_trace_initcall_level trace_initcall_level +#else +static inline void do_trace_initcall_start(initcall_t fn) +{ + if (!initcall_debug) + return; + trace_initcall_start_cb(&initcall_calltime, fn); +} +static inline void do_trace_initcall_finish(initcall_t fn, int ret) +{ + if (!initcall_debug) + return; + trace_initcall_finish_cb(&initcall_calltime, fn, ret); +} +static inline void do_trace_initcall_level(const char *level) +{ + if (!initcall_debug) + return; + trace_initcall_level_cb(NULL, level); } +#endif /* !TRACEPOINTS_ENABLED */ int __init_or_module do_one_initcall(initcall_t fn) { int count = preempt_count(); - int ret; char msgbuf[64]; + int ret; - if (initcall_debug) - ret = do_one_initcall_debug(fn); - else - ret = fn(); + if (initcall_blacklisted(fn)) + return -EPERM; + + do_trace_initcall_start(fn); + ret = fn(); + do_trace_initcall_finish(fn, ret); msgbuf[0] = 0; if (preempt_count() != count) { sprintf(msgbuf, "preemption imbalance "); - preempt_count() = count; + preempt_count_set(count); } if (irqs_disabled()) { strlcat(msgbuf, "disabled interrupts ", sizeof(msgbuf)); local_irq_enable(); } - WARN(msgbuf[0], "initcall %pF returned with %s\n", fn, msgbuf); + WARN(msgbuf[0], "initcall %pS returned with %s\n", fn, msgbuf); + add_latent_entropy(); return ret; } -extern initcall_t __initcall_start[]; -extern initcall_t __initcall0_start[]; -extern initcall_t __initcall1_start[]; -extern initcall_t __initcall2_start[]; -extern initcall_t __initcall3_start[]; -extern initcall_t __initcall4_start[]; -extern initcall_t __initcall5_start[]; -extern initcall_t __initcall6_start[]; -extern initcall_t __initcall7_start[]; -extern initcall_t __initcall_end[]; - -static initcall_t *initcall_levels[] __initdata = { +static initcall_entry_t *initcall_levels[] __initdata = { __initcall0_start, __initcall1_start, __initcall2_start, @@ -726,8 +1408,8 @@ static initcall_t *initcall_levels[] __initdata = { }; /* Keep these in sync with initcalls in include/linux/init.h */ -static char *initcall_level_names[] __initdata = { - "early", +static const char *initcall_level_names[] __initdata = { + "pure", "core", "postcore", "arch", @@ -737,28 +1419,44 @@ static char *initcall_level_names[] __initdata = { "late", }; -static void __init do_initcall_level(int level) +static int __init ignore_unknown_bootoption(char *param, char *val, + const char *unused, void *arg) +{ + return 0; +} + +static void __init do_initcall_level(int level, char *command_line) { - extern const struct kernel_param __start___param[], __stop___param[]; - initcall_t *fn; + initcall_entry_t *fn; - strcpy(static_command_line, saved_command_line); parse_args(initcall_level_names[level], - static_command_line, __start___param, + command_line, __start___param, __stop___param - __start___param, level, level, - &repair_env_string); + NULL, ignore_unknown_bootoption); + do_trace_initcall_level(initcall_level_names[level]); for (fn = initcall_levels[level]; fn < initcall_levels[level+1]; fn++) - do_one_initcall(*fn); + do_one_initcall(initcall_from_entry(fn)); } static void __init do_initcalls(void) { int level; + size_t len = saved_command_line_len + 1; + char *command_line; + + command_line = kzalloc(len, GFP_KERNEL); + if (!command_line) + panic("%s: Failed to allocate %zu bytes\n", __func__, len); - for (level = 0; level < ARRAY_SIZE(initcall_levels) - 1; level++) - do_initcall_level(level); + for (level = 0; level < ARRAY_SIZE(initcall_levels) - 1; level++) { + /* Parser modifies command_line, restore it each time */ + strcpy(command_line, saved_command_line); + do_initcall_level(level, command_line); + } + + kfree(command_line); } /* @@ -771,60 +1469,143 @@ static void __init do_initcalls(void) static void __init do_basic_setup(void) { cpuset_init_smp(); - usermodehelper_init(); - shmem_init(); driver_init(); init_irq_proc(); do_ctors(); - usermodehelper_enable(); do_initcalls(); } static void __init do_pre_smp_initcalls(void) { - initcall_t *fn; + initcall_entry_t *fn; + do_trace_initcall_level("early"); for (fn = __initcall_start; fn < __initcall0_start; fn++) - do_one_initcall(*fn); + do_one_initcall(initcall_from_entry(fn)); } -/* - * This function requests modules which should be loaded by default and is - * called twice right after initrd is mounted and right before init is - * exec'd. If such modules are on either initrd or rootfs, they will be - * loaded before control is passed to userland. - */ -void __init load_default_modules(void) +static int run_init_process(const char *init_filename) { - load_default_elevator_module(); + const char *const *p; + + argv_init[0] = init_filename; + pr_info("Run %s as init process\n", init_filename); + pr_debug(" with arguments:\n"); + for (p = argv_init; *p; p++) + pr_debug(" %s\n", *p); + pr_debug(" with environment:\n"); + for (p = envp_init; *p; p++) + pr_debug(" %s\n", *p); + return kernel_execve(init_filename, argv_init, envp_init); } -static int run_init_process(const char *init_filename) +static int try_to_run_init_process(const char *init_filename) { - argv_init[0] = init_filename; - return do_execve(init_filename, - (const char __user *const __user *)argv_init, - (const char __user *const __user *)envp_init); + int ret; + + ret = run_init_process(init_filename); + + if (ret && ret != -ENOENT) { + pr_err("Starting init: %s exists but couldn't execute it (error %d)\n", + init_filename, ret); + } + + return ret; } static noinline void __init kernel_init_freeable(void); +#if defined(CONFIG_STRICT_KERNEL_RWX) || defined(CONFIG_STRICT_MODULE_RWX) +bool rodata_enabled __ro_after_init = true; + +#ifndef arch_parse_debug_rodata +static inline bool arch_parse_debug_rodata(char *str) { return false; } +#endif + +static int __init set_debug_rodata(char *str) +{ + if (arch_parse_debug_rodata(str)) + return 0; + + if (str && !strcmp(str, "on")) + rodata_enabled = true; + else if (str && !strcmp(str, "off")) + rodata_enabled = false; + else + pr_warn("Invalid option string for rodata: '%s'\n", str); + return 0; +} +early_param("rodata", set_debug_rodata); +#endif + +static void mark_readonly(void) +{ + if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX) && rodata_enabled) { + /* + * load_module() results in W+X mappings, which are cleaned + * up with init_free_wq. Let's make sure that queued work is + * flushed so that we don't hit false positives looking for + * insecure pages which are W+X. + */ + flush_module_init_free_work(); + jump_label_init_ro(); + mark_rodata_ro(); + debug_checkwx(); + rodata_test(); + } else if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)) { + pr_info("Kernel memory protection disabled.\n"); + } else if (IS_ENABLED(CONFIG_ARCH_HAS_STRICT_KERNEL_RWX)) { + pr_warn("Kernel memory protection not selected by kernel config.\n"); + } else { + pr_warn("This architecture does not have kernel memory protection.\n"); + } +} + +void __weak free_initmem(void) +{ + free_initmem_default(POISON_FREE_INITMEM); +} + static int __ref kernel_init(void *unused) { + int ret; + + /* + * Wait until kthreadd is all set-up. + */ + wait_for_completion(&kthreadd_done); + kernel_init_freeable(); /* need to finish all async __init code before freeing the memory */ async_synchronize_full(); + + system_state = SYSTEM_FREEING_INITMEM; + kprobe_free_init_mem(); + ftrace_free_init_mem(); + kgdb_free_init_mem(); + exit_boot_config(); free_initmem(); - mark_rodata_ro(); + mark_readonly(); + + /* + * Kernel mappings are now finalized - update the userspace page-table + * to finalize PTI. + */ + pti_finalize(); + system_state = SYSTEM_RUNNING; numa_default_policy(); - flush_delayed_fput(); + rcu_end_inkernel_boot(); + + do_sysctl_args(); if (ramdisk_execute_command) { - if (!run_init_process(ramdisk_execute_command)) + ret = run_init_process(ramdisk_execute_command); + if (!ret) return 0; - pr_err("Failed to execute %s\n", ramdisk_execute_command); + pr_err("Failed to execute %s (error %d)\n", + ramdisk_execute_command, ret); } /* @@ -834,28 +1615,49 @@ static int __ref kernel_init(void *unused) * trying to recover a really broken machine. */ if (execute_command) { - if (!run_init_process(execute_command)) + ret = run_init_process(execute_command); + if (!ret) return 0; - pr_err("Failed to execute %s. Attempting defaults...\n", - execute_command); + panic("Requested init %s failed (error %d).", + execute_command, ret); } - if (!run_init_process("/sbin/init") || - !run_init_process("/etc/init") || - !run_init_process("/bin/init") || - !run_init_process("/bin/sh")) + + if (CONFIG_DEFAULT_INIT[0] != '\0') { + ret = run_init_process(CONFIG_DEFAULT_INIT); + if (ret) + pr_err("Default init %s failed (error %d)\n", + CONFIG_DEFAULT_INIT, ret); + else + return 0; + } + + if (!try_to_run_init_process("/sbin/init") || + !try_to_run_init_process("/etc/init") || + !try_to_run_init_process("/bin/init") || + !try_to_run_init_process("/bin/sh")) return 0; - panic("No init found. Try passing init= option to kernel. " - "See Linux Documentation/init.txt for guidance."); + panic("No working init found. Try passing init= option to kernel. " + "See Linux Documentation/admin-guide/init.rst for guidance."); } -static noinline void __init kernel_init_freeable(void) +/* Open /dev/console, for stdin/stdout/stderr, this should never fail */ +void __init console_on_rootfs(void) { - /* - * Wait until kthreadd is all set-up. - */ - wait_for_completion(&kthreadd_done); + struct file *file = filp_open("/dev/console", O_RDWR, 0); + + if (IS_ERR(file)) { + pr_err("Warning: unable to open an initial console.\n"); + return; + } + init_dup(file); + init_dup(file); + init_dup(file); + fput(file); +} +static noinline void __init kernel_init_freeable(void) +{ /* Now the scheduler is fully set up and can do blocking allocations */ gfp_allowed_mask = __GFP_BITS_MASK; @@ -863,38 +1665,42 @@ static noinline void __init kernel_init_freeable(void) * init can allocate pages on any node */ set_mems_allowed(node_states[N_MEMORY]); - /* - * init can run on any cpu. - */ - set_cpus_allowed_ptr(current, cpu_all_mask); - cad_pid = task_pid(current); + cad_pid = get_pid(task_pid(current)); smp_prepare_cpus(setup_max_cpus); + workqueue_init(); + + init_mm_internals(); + do_pre_smp_initcalls(); lockup_detector_init(); smp_init(); sched_init_smp(); + workqueue_init_topology(); + async_init(); + padata_init(); + page_alloc_init_late(); + do_basic_setup(); - /* Open the /dev/console on the rootfs, this should never fail */ - if (sys_open((const char __user *) "/dev/console", O_RDWR, 0) < 0) - pr_err("Warning: unable to open an initial console.\n"); + kunit_run_all_tests(); + + wait_for_initramfs(); + console_on_rootfs(); - (void) sys_dup(0); - (void) sys_dup(0); /* * check if there is an early userspace init. If yes, let it do all * the work */ - - if (!ramdisk_execute_command) - ramdisk_execute_command = "/init"; - - if (sys_access((const char __user *) ramdisk_execute_command, 0) != 0) { + int ramdisk_command_access; + ramdisk_command_access = init_eaccess(ramdisk_execute_command); + if (ramdisk_command_access != 0) { + pr_warn("check access for rdinit=%s failed: %i, ignoring\n", + ramdisk_execute_command, ramdisk_command_access); ramdisk_execute_command = NULL; prepare_namespace(); } @@ -903,8 +1709,10 @@ static noinline void __init kernel_init_freeable(void) * Ok, we have completed the initial bootup, and * we're essentially up and running. Get rid of the * initmem segments and start the user-mode stuff.. + * + * rootfs is available now, try loading the public keys + * and default modules */ - /* rootfs is available now, try loading default modules */ - load_default_modules(); + integrity_load_keys(); } |
