blob: a3e6df69120b8f591ab04cfad8250c964312793a [file] [log] [blame]
/*
* Copyright (c) 2017 Intel Corporation
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <zephyr/kernel.h>
#include <string.h>
#include <zephyr/sys/math_extras.h>
#include <zephyr/sys/rb.h>
#include <zephyr/kernel_structs.h>
#include <zephyr/sys/sys_io.h>
#include <ksched.h>
#include <zephyr/syscall.h>
#include <zephyr/internal/syscall_handler.h>
#include <zephyr/device.h>
#include <zephyr/init.h>
#include <stdbool.h>
#include <zephyr/app_memory/app_memdomain.h>
#include <zephyr/sys/libc-hooks.h>
#include <zephyr/sys/mutex.h>
#include <inttypes.h>
#include <zephyr/linker/linker-defs.h>
#ifdef Z_LIBC_PARTITION_EXISTS
K_APPMEM_PARTITION_DEFINE(z_libc_partition);
#endif
/* TODO: Find a better place to put this. Since we pull the entire
* lib..__modules__crypto__mbedtls.a globals into app shared memory
* section, we can't put this in zephyr_init.c of the mbedtls module.
*/
#ifdef CONFIG_MBEDTLS
K_APPMEM_PARTITION_DEFINE(k_mbedtls_partition);
#endif
#include <zephyr/logging/log.h>
LOG_MODULE_DECLARE(os, CONFIG_KERNEL_LOG_LEVEL);
/* The originally synchronization strategy made heavy use of recursive
* irq_locking, which ports poorly to spinlocks which are
* non-recursive. Rather than try to redesign as part of
* spinlockification, this uses multiple locks to preserve the
* original semantics exactly. The locks are named for the data they
* protect where possible, or just for the code that uses them where
* not.
*/
#ifdef CONFIG_DYNAMIC_OBJECTS
static struct k_spinlock lists_lock; /* kobj dlist */
static struct k_spinlock objfree_lock; /* k_object_free */
#ifdef CONFIG_GEN_PRIV_STACKS
/* On ARM & ARC MPU we may have two different alignment requirement
* when dynamically allocating thread stacks, one for the privileged
* stack and other for the user stack, so we need to account the
* worst alignment scenario and reserve space for that.
*/
#if defined(CONFIG_ARM_MPU) || defined(CONFIG_ARC_MPU)
#define STACK_ELEMENT_DATA_SIZE(size) \
(sizeof(struct z_stack_data) + CONFIG_PRIVILEGED_STACK_SIZE + \
Z_THREAD_STACK_OBJ_ALIGN(size) + Z_THREAD_STACK_SIZE_ADJUST(size))
#else
#define STACK_ELEMENT_DATA_SIZE(size) (sizeof(struct z_stack_data) + \
Z_THREAD_STACK_SIZE_ADJUST(size))
#endif /* CONFIG_ARM_MPU || CONFIG_ARC_MPU */
#else
#define STACK_ELEMENT_DATA_SIZE(size) Z_THREAD_STACK_SIZE_ADJUST(size)
#endif /* CONFIG_GEN_PRIV_STACKS */
#endif
static struct k_spinlock obj_lock; /* kobj struct data */
#define MAX_THREAD_BITS (CONFIG_MAX_THREAD_BYTES * 8)
#ifdef CONFIG_DYNAMIC_OBJECTS
extern uint8_t _thread_idx_map[CONFIG_MAX_THREAD_BYTES];
#endif
static void clear_perms_cb(struct k_object *ko, void *ctx_ptr);
const char *otype_to_str(enum k_objects otype)
{
const char *ret;
/* -fdata-sections doesn't work right except in very very recent
* GCC and these literal strings would appear in the binary even if
* otype_to_str was omitted by the linker
*/
#ifdef CONFIG_LOG
switch (otype) {
/* otype-to-str.h is generated automatically during build by
* gen_kobject_list.py
*/
case K_OBJ_ANY:
ret = "generic";
break;
#include <otype-to-str.h>
default:
ret = "?";
break;
}
#else
ARG_UNUSED(otype);
ret = NULL;
#endif
return ret;
}
struct perm_ctx {
int parent_id;
int child_id;
struct k_thread *parent;
};
#ifdef CONFIG_GEN_PRIV_STACKS
/* See write_gperf_table() in scripts/build/gen_kobject_list.py. The privilege
* mode stacks are allocated as an array. The base of the array is
* aligned to Z_PRIVILEGE_STACK_ALIGN, and all members must be as well.
*/
uint8_t *z_priv_stack_find(k_thread_stack_t *stack)
{
struct k_object *obj = k_object_find(stack);
__ASSERT(obj != NULL, "stack object not found");
__ASSERT(obj->type == K_OBJ_THREAD_STACK_ELEMENT,
"bad stack object");
return obj->data.stack_data->priv;
}
#endif /* CONFIG_GEN_PRIV_STACKS */
#ifdef CONFIG_DYNAMIC_OBJECTS
/*
* Note that dyn_obj->data is where the kernel object resides
* so it is the one that actually needs to be aligned.
* Due to the need to get the the fields inside struct dyn_obj
* from kernel object pointers (i.e. from data[]), the offset
* from data[] needs to be fixed at build time. Therefore,
* data[] is declared with __aligned(), such that when dyn_obj
* is allocated with alignment, data[] is also aligned.
* Due to this requirement, data[] needs to be aligned with
* the maximum alignment needed for all kernel objects
* (hence the following DYN_OBJ_DATA_ALIGN).
*/
#ifdef ARCH_DYNAMIC_OBJ_K_THREAD_ALIGNMENT
#define DYN_OBJ_DATA_ALIGN_K_THREAD (ARCH_DYNAMIC_OBJ_K_THREAD_ALIGNMENT)
#else
#define DYN_OBJ_DATA_ALIGN_K_THREAD (sizeof(void *))
#endif
#ifdef CONFIG_DYNAMIC_THREAD_STACK_SIZE
#ifndef CONFIG_MPU_STACK_GUARD
#define DYN_OBJ_DATA_ALIGN_K_THREAD_STACK \
Z_THREAD_STACK_OBJ_ALIGN(CONFIG_PRIVILEGED_STACK_SIZE)
#else
#define DYN_OBJ_DATA_ALIGN_K_THREAD_STACK \
Z_THREAD_STACK_OBJ_ALIGN(CONFIG_DYNAMIC_THREAD_STACK_SIZE)
#endif /* !CONFIG_MPU_STACK_GUARD */
#else
#define DYN_OBJ_DATA_ALIGN_K_THREAD_STACK \
Z_THREAD_STACK_OBJ_ALIGN(ARCH_STACK_PTR_ALIGN)
#endif /* CONFIG_DYNAMIC_THREAD_STACK_SIZE */
#define DYN_OBJ_DATA_ALIGN \
MAX(DYN_OBJ_DATA_ALIGN_K_THREAD, (sizeof(void *)))
struct dyn_obj {
struct k_object kobj;
sys_dnode_t dobj_list;
/* The object itself */
void *data;
};
extern struct k_object *z_object_gperf_find(const void *obj);
extern void z_object_gperf_wordlist_foreach(_wordlist_cb_func_t func,
void *context);
/*
* Linked list of allocated kernel objects, for iteration over all allocated
* objects (and potentially deleting them during iteration).
*/
static sys_dlist_t obj_list = SYS_DLIST_STATIC_INIT(&obj_list);
/*
* TODO: Write some hash table code that will replace obj_list.
*/
static size_t obj_size_get(enum k_objects otype)
{
size_t ret;
switch (otype) {
#include <otype-to-size.h>
default:
ret = sizeof(const struct device);
break;
}
return ret;
}
static size_t obj_align_get(enum k_objects otype)
{
size_t ret;
switch (otype) {
case K_OBJ_THREAD:
#ifdef ARCH_DYNAMIC_OBJ_K_THREAD_ALIGNMENT
ret = ARCH_DYNAMIC_OBJ_K_THREAD_ALIGNMENT;
#else
ret = __alignof(struct dyn_obj);
#endif
break;
default:
ret = __alignof(struct dyn_obj);
break;
}
return ret;
}
static struct dyn_obj *dyn_object_find(void *obj)
{
struct dyn_obj *node;
k_spinlock_key_t key;
/* For any dynamically allocated kernel object, the object
* pointer is just a member of the containing struct dyn_obj,
* so just a little arithmetic is necessary to locate the
* corresponding struct rbnode
*/
key = k_spin_lock(&lists_lock);
SYS_DLIST_FOR_EACH_CONTAINER(&obj_list, node, dobj_list) {
if (node->kobj.name == obj) {
goto end;
}
}
/* No object found */
node = NULL;
end:
k_spin_unlock(&lists_lock, key);
return node;
}
/**
* @internal
*
* @brief Allocate a new thread index for a new thread.
*
* This finds an unused thread index that can be assigned to a new
* thread. If too many threads have been allocated, the kernel will
* run out of indexes and this function will fail.
*
* Note that if an unused index is found, that index will be marked as
* used after return of this function.
*
* @param tidx The new thread index if successful
*
* @return true if successful, false if failed
**/
static bool thread_idx_alloc(uintptr_t *tidx)
{
int i;
int idx;
int base;
base = 0;
for (i = 0; i < CONFIG_MAX_THREAD_BYTES; i++) {
idx = find_lsb_set(_thread_idx_map[i]);
if (idx != 0) {
*tidx = base + (idx - 1);
sys_bitfield_clear_bit((mem_addr_t)_thread_idx_map,
*tidx);
/* Clear permission from all objects */
k_object_wordlist_foreach(clear_perms_cb,
(void *)*tidx);
return true;
}
base += 8;
}
return false;
}
/**
* @internal
*
* @brief Free a thread index.
*
* This frees a thread index so it can be used by another
* thread.
*
* @param tidx The thread index to be freed
**/
static void thread_idx_free(uintptr_t tidx)
{
/* To prevent leaked permission when index is recycled */
k_object_wordlist_foreach(clear_perms_cb, (void *)tidx);
sys_bitfield_set_bit((mem_addr_t)_thread_idx_map, tidx);
}
static struct k_object *dynamic_object_create(enum k_objects otype, size_t align,
size_t size)
{
struct dyn_obj *dyn;
dyn = z_thread_aligned_alloc(align, sizeof(struct dyn_obj));
if (dyn == NULL) {
return NULL;
}
if (otype == K_OBJ_THREAD_STACK_ELEMENT) {
size_t adjusted_size;
if (size == 0) {
k_free(dyn);
return NULL;
}
adjusted_size = STACK_ELEMENT_DATA_SIZE(size);
dyn->data = z_thread_aligned_alloc(DYN_OBJ_DATA_ALIGN_K_THREAD_STACK,
adjusted_size);
if (dyn->data == NULL) {
k_free(dyn);
return NULL;
}
#ifdef CONFIG_GEN_PRIV_STACKS
struct z_stack_data *stack_data = (struct z_stack_data *)
((uint8_t *)dyn->data + adjusted_size - sizeof(*stack_data));
stack_data->priv = (uint8_t *)dyn->data;
dyn->kobj.data.stack_data = stack_data;
#if defined(CONFIG_ARM_MPU) || defined(CONFIG_ARC_MPU)
dyn->kobj.name = (void *)ROUND_UP(
((uint8_t *)dyn->data + CONFIG_PRIVILEGED_STACK_SIZE),
Z_THREAD_STACK_OBJ_ALIGN(size));
#else
dyn->kobj.name = dyn->data;
#endif
#else
dyn->kobj.name = dyn->data;
#endif
} else {
dyn->data = z_thread_aligned_alloc(align, obj_size_get(otype) + size);
if (dyn->data == NULL) {
k_free(dyn->data);
return NULL;
}
dyn->kobj.name = dyn->data;
}
dyn->kobj.type = otype;
dyn->kobj.flags = 0;
(void)memset(dyn->kobj.perms, 0, CONFIG_MAX_THREAD_BYTES);
k_spinlock_key_t key = k_spin_lock(&lists_lock);
sys_dlist_append(&obj_list, &dyn->dobj_list);
k_spin_unlock(&lists_lock, key);
return &dyn->kobj;
}
struct k_object *k_object_create_dynamic_aligned(size_t align, size_t size)
{
struct k_object *obj = dynamic_object_create(K_OBJ_ANY, align, size);
if (obj == NULL) {
LOG_ERR("could not allocate kernel object, out of memory");
}
return obj;
}
static void *z_object_alloc(enum k_objects otype, size_t size)
{
struct k_object *zo;
uintptr_t tidx = 0;
if (otype <= K_OBJ_ANY || otype >= K_OBJ_LAST) {
LOG_ERR("bad object type %d requested", otype);
return NULL;
}
switch (otype) {
case K_OBJ_THREAD:
if (!thread_idx_alloc(&tidx)) {
LOG_ERR("out of free thread indexes");
return NULL;
}
break;
/* The following are currently not allowed at all */
case K_OBJ_FUTEX: /* Lives in user memory */
case K_OBJ_SYS_MUTEX: /* Lives in user memory */
case K_OBJ_NET_SOCKET: /* Indeterminate size */
LOG_ERR("forbidden object type '%s' requested",
otype_to_str(otype));
return NULL;
default:
/* Remainder within bounds are permitted */
break;
}
zo = dynamic_object_create(otype, obj_align_get(otype), size);
if (zo == NULL) {
if (otype == K_OBJ_THREAD) {
thread_idx_free(tidx);
}
return NULL;
}
if (otype == K_OBJ_THREAD) {
zo->data.thread_id = tidx;
}
/* The allocating thread implicitly gets permission on kernel objects
* that it allocates
*/
k_thread_perms_set(zo, _current);
/* Activates reference counting logic for automatic disposal when
* all permissions have been revoked
*/
zo->flags |= K_OBJ_FLAG_ALLOC;
return zo->name;
}
void *z_impl_k_object_alloc(enum k_objects otype)
{
return z_object_alloc(otype, 0);
}
void *z_impl_k_object_alloc_size(enum k_objects otype, size_t size)
{
return z_object_alloc(otype, size);
}
void k_object_free(void *obj)
{
struct dyn_obj *dyn;
/* This function is intentionally not exposed to user mode.
* There's currently no robust way to track that an object isn't
* being used by some other thread
*/
k_spinlock_key_t key = k_spin_lock(&objfree_lock);
dyn = dyn_object_find(obj);
if (dyn != NULL) {
sys_dlist_remove(&dyn->dobj_list);
if (dyn->kobj.type == K_OBJ_THREAD) {
thread_idx_free(dyn->kobj.data.thread_id);
}
}
k_spin_unlock(&objfree_lock, key);
if (dyn != NULL) {
k_free(dyn->data);
k_free(dyn);
}
}
struct k_object *k_object_find(const void *obj)
{
struct k_object *ret;
ret = z_object_gperf_find(obj);
if (ret == NULL) {
struct dyn_obj *dyn;
/* The cast to pointer-to-non-const violates MISRA
* 11.8 but is justified since we know dynamic objects
* were not declared with a const qualifier.
*/
dyn = dyn_object_find((void *)obj);
if (dyn != NULL) {
ret = &dyn->kobj;
}
}
return ret;
}
void k_object_wordlist_foreach(_wordlist_cb_func_t func, void *context)
{
struct dyn_obj *obj, *next;
z_object_gperf_wordlist_foreach(func, context);
k_spinlock_key_t key = k_spin_lock(&lists_lock);
SYS_DLIST_FOR_EACH_CONTAINER_SAFE(&obj_list, obj, next, dobj_list) {
func(&obj->kobj, context);
}
k_spin_unlock(&lists_lock, key);
}
#endif /* CONFIG_DYNAMIC_OBJECTS */
static unsigned int thread_index_get(struct k_thread *thread)
{
struct k_object *ko;
ko = k_object_find(thread);
if (ko == NULL) {
return -1;
}
return ko->data.thread_id;
}
static void unref_check(struct k_object *ko, uintptr_t index)
{
k_spinlock_key_t key = k_spin_lock(&obj_lock);
sys_bitfield_clear_bit((mem_addr_t)&ko->perms, index);
#ifdef CONFIG_DYNAMIC_OBJECTS
if ((ko->flags & K_OBJ_FLAG_ALLOC) == 0U) {
/* skip unref check for static kernel object */
goto out;
}
void *vko = ko;
struct dyn_obj *dyn = CONTAINER_OF(vko, struct dyn_obj, kobj);
__ASSERT(IS_PTR_ALIGNED(dyn, struct dyn_obj), "unaligned z_object");
for (int i = 0; i < CONFIG_MAX_THREAD_BYTES; i++) {
if (ko->perms[i] != 0U) {
goto out;
}
}
/* This object has no more references. Some objects may have
* dynamically allocated resources, require cleanup, or need to be
* marked as uninitailized when all references are gone. What
* specifically needs to happen depends on the object type.
*/
switch (ko->type) {
#ifdef CONFIG_PIPES
case K_OBJ_PIPE:
k_pipe_cleanup((struct k_pipe *)ko->name);
break;
#endif
case K_OBJ_MSGQ:
k_msgq_cleanup((struct k_msgq *)ko->name);
break;
case K_OBJ_STACK:
k_stack_cleanup((struct k_stack *)ko->name);
break;
default:
/* Nothing to do */
break;
}
sys_dlist_remove(&dyn->dobj_list);
k_free(dyn->data);
k_free(dyn);
out:
#endif
k_spin_unlock(&obj_lock, key);
}
static void wordlist_cb(struct k_object *ko, void *ctx_ptr)
{
struct perm_ctx *ctx = (struct perm_ctx *)ctx_ptr;
if (sys_bitfield_test_bit((mem_addr_t)&ko->perms, ctx->parent_id) &&
(struct k_thread *)ko->name != ctx->parent) {
sys_bitfield_set_bit((mem_addr_t)&ko->perms, ctx->child_id);
}
}
void k_thread_perms_inherit(struct k_thread *parent, struct k_thread *child)
{
struct perm_ctx ctx = {
thread_index_get(parent),
thread_index_get(child),
parent
};
if ((ctx.parent_id != -1) && (ctx.child_id != -1)) {
k_object_wordlist_foreach(wordlist_cb, &ctx);
}
}
void k_thread_perms_set(struct k_object *ko, struct k_thread *thread)
{
int index = thread_index_get(thread);
if (index != -1) {
sys_bitfield_set_bit((mem_addr_t)&ko->perms, index);
}
}
void k_thread_perms_clear(struct k_object *ko, struct k_thread *thread)
{
int index = thread_index_get(thread);
if (index != -1) {
sys_bitfield_clear_bit((mem_addr_t)&ko->perms, index);
unref_check(ko, index);
}
}
static void clear_perms_cb(struct k_object *ko, void *ctx_ptr)
{
uintptr_t id = (uintptr_t)ctx_ptr;
unref_check(ko, id);
}
void k_thread_perms_all_clear(struct k_thread *thread)
{
uintptr_t index = thread_index_get(thread);
if ((int)index != -1) {
k_object_wordlist_foreach(clear_perms_cb, (void *)index);
}
}
static int thread_perms_test(struct k_object *ko)
{
int index;
if ((ko->flags & K_OBJ_FLAG_PUBLIC) != 0U) {
return 1;
}
index = thread_index_get(_current);
if (index != -1) {
return sys_bitfield_test_bit((mem_addr_t)&ko->perms, index);
}
return 0;
}
static void dump_permission_error(struct k_object *ko)
{
int index = thread_index_get(_current);
LOG_ERR("thread %p (%d) does not have permission on %s %p",
_current, index,
otype_to_str(ko->type), ko->name);
LOG_HEXDUMP_ERR(ko->perms, sizeof(ko->perms), "permission bitmap");
}
void k_object_dump_error(int retval, const void *obj, struct k_object *ko,
enum k_objects otype)
{
switch (retval) {
case -EBADF:
LOG_ERR("%p is not a valid %s", obj, otype_to_str(otype));
if (ko == NULL) {
LOG_ERR("address is not a known kernel object");
} else {
LOG_ERR("address is actually a %s",
otype_to_str(ko->type));
}
break;
case -EPERM:
dump_permission_error(ko);
break;
case -EINVAL:
LOG_ERR("%p used before initialization", obj);
break;
case -EADDRINUSE:
LOG_ERR("%p %s in use", obj, otype_to_str(otype));
break;
default:
/* Not handled error */
break;
}
}
void z_impl_k_object_access_grant(const void *object, struct k_thread *thread)
{
struct k_object *ko = k_object_find(object);
if (ko != NULL) {
k_thread_perms_set(ko, thread);
}
}
void k_object_access_revoke(const void *object, struct k_thread *thread)
{
struct k_object *ko = k_object_find(object);
if (ko != NULL) {
k_thread_perms_clear(ko, thread);
}
}
void z_impl_k_object_release(const void *object)
{
k_object_access_revoke(object, _current);
}
void k_object_access_all_grant(const void *object)
{
struct k_object *ko = k_object_find(object);
if (ko != NULL) {
ko->flags |= K_OBJ_FLAG_PUBLIC;
}
}
int k_object_validate(struct k_object *ko, enum k_objects otype,
enum _obj_init_check init)
{
if (unlikely((ko == NULL) ||
(otype != K_OBJ_ANY && ko->type != otype))) {
return -EBADF;
}
/* Manipulation of any kernel objects by a user thread requires that
* thread be granted access first, even for uninitialized objects
*/
if (unlikely(thread_perms_test(ko) == 0)) {
return -EPERM;
}
/* Initialization state checks. _OBJ_INIT_ANY, we don't care */
if (likely(init == _OBJ_INIT_TRUE)) {
/* Object MUST be initialized */
if (unlikely((ko->flags & K_OBJ_FLAG_INITIALIZED) == 0U)) {
return -EINVAL;
}
} else if (init == _OBJ_INIT_FALSE) { /* _OBJ_INIT_FALSE case */
/* Object MUST NOT be initialized */
if (unlikely((ko->flags & K_OBJ_FLAG_INITIALIZED) != 0U)) {
return -EADDRINUSE;
}
} else {
/* _OBJ_INIT_ANY */
}
return 0;
}
void k_object_init(const void *obj)
{
struct k_object *ko;
/* By the time we get here, if the caller was from userspace, all the
* necessary checks have been done in k_object_validate(), which takes
* place before the object is initialized.
*
* This function runs after the object has been initialized and
* finalizes it
*/
ko = k_object_find(obj);
if (ko == NULL) {
/* Supervisor threads can ignore rules about kernel objects
* and may declare them on stacks, etc. Such objects will never
* be usable from userspace, but we shouldn't explode.
*/
return;
}
/* Allows non-initialization system calls to be made on this object */
ko->flags |= K_OBJ_FLAG_INITIALIZED;
}
void k_object_recycle(const void *obj)
{
struct k_object *ko = k_object_find(obj);
if (ko != NULL) {
(void)memset(ko->perms, 0, sizeof(ko->perms));
k_thread_perms_set(ko, _current);
ko->flags |= K_OBJ_FLAG_INITIALIZED;
}
}
void k_object_uninit(const void *obj)
{
struct k_object *ko;
/* See comments in k_object_init() */
ko = k_object_find(obj);
if (ko == NULL) {
return;
}
ko->flags &= ~K_OBJ_FLAG_INITIALIZED;
}
/*
* Copy to/from helper functions used in syscall handlers
*/
void *k_usermode_alloc_from_copy(const void *src, size_t size)
{
void *dst = NULL;
/* Does the caller in user mode have access to read this memory? */
if (K_SYSCALL_MEMORY_READ(src, size)) {
goto out_err;
}
dst = z_thread_malloc(size);
if (dst == NULL) {
LOG_ERR("out of thread resource pool memory (%zu)", size);
goto out_err;
}
(void)memcpy(dst, src, size);
out_err:
return dst;
}
static int user_copy(void *dst, const void *src, size_t size, bool to_user)
{
int ret = EFAULT;
/* Does the caller in user mode have access to this memory? */
if (to_user ? K_SYSCALL_MEMORY_WRITE(dst, size) :
K_SYSCALL_MEMORY_READ(src, size)) {
goto out_err;
}
(void)memcpy(dst, src, size);
ret = 0;
out_err:
return ret;
}
int k_usermode_from_copy(void *dst, const void *src, size_t size)
{
return user_copy(dst, src, size, false);
}
int k_usermode_to_copy(void *dst, const void *src, size_t size)
{
return user_copy(dst, src, size, true);
}
char *k_usermode_string_alloc_copy(const char *src, size_t maxlen)
{
size_t actual_len;
int err;
char *ret = NULL;
actual_len = k_usermode_string_nlen(src, maxlen, &err);
if (err != 0) {
goto out;
}
if (actual_len == maxlen) {
/* Not NULL terminated */
LOG_ERR("string too long %p (%zu)", src, actual_len);
goto out;
}
if (size_add_overflow(actual_len, 1, &actual_len)) {
LOG_ERR("overflow");
goto out;
}
ret = k_usermode_alloc_from_copy(src, actual_len);
/* Someone may have modified the source string during the above
* checks. Ensure what we actually copied is still terminated
* properly.
*/
if (ret != NULL) {
ret[actual_len - 1U] = '\0';
}
out:
return ret;
}
int k_usermode_string_copy(char *dst, const char *src, size_t maxlen)
{
size_t actual_len;
int ret, err;
actual_len = k_usermode_string_nlen(src, maxlen, &err);
if (err != 0) {
ret = EFAULT;
goto out;
}
if (actual_len == maxlen) {
/* Not NULL terminated */
LOG_ERR("string too long %p (%zu)", src, actual_len);
ret = EINVAL;
goto out;
}
if (size_add_overflow(actual_len, 1, &actual_len)) {
LOG_ERR("overflow");
ret = EINVAL;
goto out;
}
ret = k_usermode_from_copy(dst, src, actual_len);
/* See comment above in k_usermode_string_alloc_copy() */
dst[actual_len - 1] = '\0';
out:
return ret;
}
/*
* Application memory region initialization
*/
extern char __app_shmem_regions_start[];
extern char __app_shmem_regions_end[];
static int app_shmem_bss_zero(void)
{
struct z_app_region *region, *end;
end = (struct z_app_region *)&__app_shmem_regions_end;
region = (struct z_app_region *)&__app_shmem_regions_start;
for ( ; region < end; region++) {
#if defined(CONFIG_DEMAND_PAGING) && !defined(CONFIG_LINKER_GENERIC_SECTIONS_PRESENT_AT_BOOT)
/* When BSS sections are not present at boot, we need to wait for
* paging mechanism to be initialized before we can zero out BSS.
*/
extern bool z_sys_post_kernel;
bool do_clear = z_sys_post_kernel;
/* During pre-kernel init, z_sys_post_kernel == false, but
* with pinned rodata region, so clear. Otherwise skip.
* In post-kernel init, z_sys_post_kernel == true,
* skip those in pinned rodata region as they have already
* been cleared and possibly already in use. Otherwise clear.
*/
if (((uint8_t *)region->bss_start >= (uint8_t *)_app_smem_pinned_start) &&
((uint8_t *)region->bss_start < (uint8_t *)_app_smem_pinned_end)) {
do_clear = !do_clear;
}
if (do_clear)
#endif /* CONFIG_DEMAND_PAGING && !CONFIG_LINKER_GENERIC_SECTIONS_PRESENT_AT_BOOT */
{
(void)memset(region->bss_start, 0, region->bss_size);
}
}
return 0;
}
SYS_INIT_NAMED(app_shmem_bss_zero_pre, app_shmem_bss_zero,
PRE_KERNEL_1, CONFIG_KERNEL_INIT_PRIORITY_DEFAULT);
#if defined(CONFIG_DEMAND_PAGING) && !defined(CONFIG_LINKER_GENERIC_SECTIONS_PRESENT_AT_BOOT)
/* When BSS sections are not present at boot, we need to wait for
* paging mechanism to be initialized before we can zero out BSS.
*/
SYS_INIT_NAMED(app_shmem_bss_zero_post, app_shmem_bss_zero,
POST_KERNEL, CONFIG_KERNEL_INIT_PRIORITY_DEFAULT);
#endif /* CONFIG_DEMAND_PAGING && !CONFIG_LINKER_GENERIC_SECTIONS_PRESENT_AT_BOOT */
/*
* Default handlers if otherwise unimplemented
*/
static uintptr_t handler_bad_syscall(uintptr_t bad_id, uintptr_t arg2,
uintptr_t arg3, uintptr_t arg4,
uintptr_t arg5, uintptr_t arg6,
void *ssf)
{
LOG_ERR("Bad system call id %" PRIuPTR " invoked", bad_id);
arch_syscall_oops(ssf);
CODE_UNREACHABLE; /* LCOV_EXCL_LINE */
}
static uintptr_t handler_no_syscall(uintptr_t arg1, uintptr_t arg2,
uintptr_t arg3, uintptr_t arg4,
uintptr_t arg5, uintptr_t arg6, void *ssf)
{
LOG_ERR("Unimplemented system call");
arch_syscall_oops(ssf);
CODE_UNREACHABLE; /* LCOV_EXCL_LINE */
}
#include <syscall_dispatch.c>