#include <linux/kobject.h>
#include <linux/device.h>
#include <linux/slab.h>
+#include <linux/pstore.h>
#include <asm/uaccess.h>
MODULE_LICENSE("GPL");
MODULE_VERSION(EFIVARS_VERSION);
+#define DUMP_NAME_LEN 52
+
/*
* The maximum size of VariableName + Data = 1024
* Therefore, it's reasonable to save that much
ssize_t (*store)(struct efivar_entry *entry, const char *buf, size_t count);
};
+#define PSTORE_EFI_ATTRIBUTES \
+ (EFI_VARIABLE_NON_VOLATILE | \
+ EFI_VARIABLE_BOOTSERVICE_ACCESS | \
+ EFI_VARIABLE_RUNTIME_ACCESS)
#define EFIVAR_ATTR(_name, _mode, _show, _store) \
struct efivar_attribute efivar_attr_##_name = { \
/* Return the number of unicode characters in data */
static unsigned long
-utf8_strlen(efi_char16_t *data, unsigned long maxlength)
+utf16_strnlen(efi_char16_t *s, size_t maxlength)
{
unsigned long length = 0;
- while (*data++ != 0 && length < maxlength)
+ while (*s++ != 0 && length < maxlength)
length++;
return length;
}
+static inline unsigned long
+utf16_strlen(efi_char16_t *s)
+{
+ return utf16_strnlen(s, ~0UL);
+}
+
/*
* Return the number of bytes is the length of this string
* Note: this is NOT the same as the number of unicode characters
*/
static inline unsigned long
-utf8_strsize(efi_char16_t *data, unsigned long maxlength)
+utf16_strsize(efi_char16_t *data, unsigned long maxlength)
+{
+ return utf16_strnlen(data, maxlength/sizeof(efi_char16_t)) * sizeof(efi_char16_t);
+}
+
+static inline int
+utf16_strncmp(const efi_char16_t *a, const efi_char16_t *b, size_t len)
+{
+ while (1) {
+ if (len == 0)
+ return 0;
+ if (*a < *b)
+ return -1;
+ if (*a > *b)
+ return 1;
+ if (*a == 0) /* implies *b == 0 */
+ return 0;
+ a++;
+ b++;
+ len--;
+ }
+}
+
+static bool
+validate_device_path(struct efi_variable *var, int match, u8 *buffer,
+ unsigned long len)
+{
+ struct efi_generic_dev_path *node;
+ int offset = 0;
+
+ node = (struct efi_generic_dev_path *)buffer;
+
+ if (len < sizeof(*node))
+ return false;
+
+ while (offset <= len - sizeof(*node) &&
+ node->length >= sizeof(*node) &&
+ node->length <= len - offset) {
+ offset += node->length;
+
+ if ((node->type == EFI_DEV_END_PATH ||
+ node->type == EFI_DEV_END_PATH2) &&
+ node->sub_type == EFI_DEV_END_ENTIRE)
+ return true;
+
+ node = (struct efi_generic_dev_path *)(buffer + offset);
+ }
+
+ /*
+ * If we're here then either node->length pointed past the end
+ * of the buffer or we reached the end of the buffer without
+ * finding a device path end node.
+ */
+ return false;
+}
+
+static bool
+validate_boot_order(struct efi_variable *var, int match, u8 *buffer,
+ unsigned long len)
{
- return utf8_strlen(data, maxlength/sizeof(efi_char16_t)) * sizeof(efi_char16_t);
+ /* An array of 16-bit integers */
+ if ((len % 2) != 0)
+ return false;
+
+ return true;
+}
+
+static bool
+validate_load_option(struct efi_variable *var, int match, u8 *buffer,
+ unsigned long len)
+{
+ u16 filepathlength;
+ int i, desclength = 0, namelen;
+
+ namelen = utf16_strnlen(var->VariableName, sizeof(var->VariableName));
+
+ /* Either "Boot" or "Driver" followed by four digits of hex */
+ for (i = match; i < match+4; i++) {
+ if (var->VariableName[i] > 127 ||
+ hex_to_bin(var->VariableName[i] & 0xff) < 0)
+ return true;
+ }
+
+ /* Reject it if there's 4 digits of hex and then further content */
+ if (namelen > match + 4)
+ return false;
+
+ /* A valid entry must be at least 8 bytes */
+ if (len < 8)
+ return false;
+
+ filepathlength = buffer[4] | buffer[5] << 8;
+
+ /*
+ * There's no stored length for the description, so it has to be
+ * found by hand
+ */
+ desclength = utf16_strsize((efi_char16_t *)(buffer + 6), len - 6) + 2;
+
+ /* Each boot entry must have a descriptor */
+ if (!desclength)
+ return false;
+
+ /*
+ * If the sum of the length of the description, the claimed filepath
+ * length and the original header are greater than the length of the
+ * variable, it's malformed
+ */
+ if ((desclength + filepathlength + 6) > len)
+ return false;
+
+ /*
+ * And, finally, check the filepath
+ */
+ return validate_device_path(var, match, buffer + desclength + 6,
+ filepathlength);
+}
+
+static bool
+validate_uint16(struct efi_variable *var, int match, u8 *buffer,
+ unsigned long len)
+{
+ /* A single 16-bit integer */
+ if (len != 2)
+ return false;
+
+ return true;
+}
+
+static bool
+validate_ascii_string(struct efi_variable *var, int match, u8 *buffer,
+ unsigned long len)
+{
+ int i;
+
+ for (i = 0; i < len; i++) {
+ if (buffer[i] > 127)
+ return false;
+
+ if (buffer[i] == 0)
+ return true;
+ }
+
+ return false;
+}
+
+struct variable_validate {
+ char *name;
+ bool (*validate)(struct efi_variable *var, int match, u8 *data,
+ unsigned long len);
+};
+
+static const struct variable_validate variable_validate[] = {
+ { "BootNext", validate_uint16 },
+ { "BootOrder", validate_boot_order },
+ { "DriverOrder", validate_boot_order },
+ { "Boot*", validate_load_option },
+ { "Driver*", validate_load_option },
+ { "ConIn", validate_device_path },
+ { "ConInDev", validate_device_path },
+ { "ConOut", validate_device_path },
+ { "ConOutDev", validate_device_path },
+ { "ErrOut", validate_device_path },
+ { "ErrOutDev", validate_device_path },
+ { "Timeout", validate_uint16 },
+ { "Lang", validate_ascii_string },
+ { "PlatformLang", validate_ascii_string },
+ { "", NULL },
+};
+
+static bool
+validate_var(struct efi_variable *var, u8 *data, unsigned long len)
+{
+ int i;
+ u16 *unicode_name = var->VariableName;
+
+ for (i = 0; variable_validate[i].validate != NULL; i++) {
+ const char *name = variable_validate[i].name;
+ int match;
+
+ for (match = 0; ; match++) {
+ char c = name[match];
+ u16 u = unicode_name[match];
+
+ /* All special variables are plain ascii */
+ if (u > 127)
+ return true;
+
+ /* Wildcard in the matching name means we've matched */
+ if (c == '*')
+ return variable_validate[i].validate(var,
+ match, data, len);
+
+ /* Case sensitive match */
+ if (c != u)
+ break;
+
+ /* Reached the end of the string while matching */
+ if (!c)
+ return variable_validate[i].validate(var,
+ match, data, len);
+ }
+ }
+
+ return true;
}
static efi_status_t
-get_var_data(struct efivars *efivars, struct efi_variable *var)
+get_var_data_locked(struct efivars *efivars, struct efi_variable *var)
{
efi_status_t status;
- spin_lock(&efivars->lock);
var->DataSize = 1024;
status = efivars->ops->get_variable(var->VariableName,
&var->VendorGuid,
&var->Attributes,
&var->DataSize,
var->Data);
+ return status;
+}
+
+static efi_status_t
+get_var_data(struct efivars *efivars, struct efi_variable *var)
+{
+ efi_status_t status;
+
+ spin_lock(&efivars->lock);
+ status = get_var_data_locked(efivars, var);
spin_unlock(&efivars->lock);
+
if (status != EFI_SUCCESS) {
printk(KERN_WARNING "efivars: get_variable() failed 0x%lx!\n",
status);
return -EINVAL;
}
+ if ((new_var->Attributes & ~EFI_VARIABLE_MASK) != 0 ||
+ validate_var(new_var, new_var->Data, new_var->DataSize) == false) {
+ printk(KERN_ERR "efivars: Malformed variable content\n");
+ return -EINVAL;
+ }
+
spin_lock(&efivars->lock);
status = efivars->ops->set_variable(new_var->VariableName,
&new_var->VendorGuid,
.default_attrs = def_attrs,
};
+static struct pstore_info efi_pstore_info;
+
static inline void
efivar_unregister(struct efivar_entry *var)
{
kobject_put(&var->kobj);
}
+#ifdef CONFIG_PSTORE
+
+static int efi_pstore_open(struct pstore_info *psi)
+{
+ struct efivars *efivars = psi->data;
+
+ spin_lock(&efivars->lock);
+ efivars->walk_entry = list_first_entry(&efivars->list,
+ struct efivar_entry, list);
+ return 0;
+}
+
+static int efi_pstore_close(struct pstore_info *psi)
+{
+ struct efivars *efivars = psi->data;
+
+ spin_unlock(&efivars->lock);
+ return 0;
+}
+
+static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type,
+ struct timespec *timespec,
+ char **buf, struct pstore_info *psi)
+{
+ efi_guid_t vendor = LINUX_EFI_CRASH_GUID;
+ struct efivars *efivars = psi->data;
+ char name[DUMP_NAME_LEN];
+ int i;
+ unsigned int part, size;
+ unsigned long time;
+
+ while (&efivars->walk_entry->list != &efivars->list) {
+ if (!efi_guidcmp(efivars->walk_entry->var.VendorGuid,
+ vendor)) {
+ for (i = 0; i < DUMP_NAME_LEN; i++) {
+ name[i] = efivars->walk_entry->var.VariableName[i];
+ }
+ if (sscanf(name, "dump-type%u-%u-%lu", type, &part, &time) == 3) {
+ *id = part;
+ timespec->tv_sec = time;
+ timespec->tv_nsec = 0;
+ get_var_data_locked(efivars, &efivars->walk_entry->var);
+ size = efivars->walk_entry->var.DataSize;
+ *buf = kmalloc(size, GFP_KERNEL);
+ if (*buf == NULL)
+ return -ENOMEM;
+ memcpy(*buf, efivars->walk_entry->var.Data,
+ size);
+ efivars->walk_entry = list_entry(efivars->walk_entry->list.next,
+ struct efivar_entry, list);
+ return size;
+ }
+ }
+ efivars->walk_entry = list_entry(efivars->walk_entry->list.next,
+ struct efivar_entry, list);
+ }
+ return 0;
+}
+
+static int efi_pstore_write(enum pstore_type_id type,
+ enum kmsg_dump_reason reason, u64 *id,
+ unsigned int part, size_t size, struct pstore_info *psi)
+{
+ char name[DUMP_NAME_LEN];
+ char stub_name[DUMP_NAME_LEN];
+ efi_char16_t efi_name[DUMP_NAME_LEN];
+ efi_guid_t vendor = LINUX_EFI_CRASH_GUID;
+ struct efivars *efivars = psi->data;
+ struct efivar_entry *entry, *found = NULL;
+ int i, ret = 0;
+
+ sprintf(stub_name, "dump-type%u-%u-", type, part);
+ sprintf(name, "%s%lu", stub_name, get_seconds());
+
+ spin_lock(&efivars->lock);
+
+ for (i = 0; i < DUMP_NAME_LEN; i++)
+ efi_name[i] = stub_name[i];
+
+ /*
+ * Clean up any entries with the same name
+ */
+
+ list_for_each_entry(entry, &efivars->list, list) {
+ get_var_data_locked(efivars, &entry->var);
+
+ if (efi_guidcmp(entry->var.VendorGuid, vendor))
+ continue;
+ if (utf16_strncmp(entry->var.VariableName, efi_name,
+ utf16_strlen(efi_name)))
+ continue;
+ /* Needs to be a prefix */
+ if (entry->var.VariableName[utf16_strlen(efi_name)] == 0)
+ continue;
+
+ /* found */
+ found = entry;
+ efivars->ops->set_variable(entry->var.VariableName,
+ &entry->var.VendorGuid,
+ PSTORE_EFI_ATTRIBUTES,
+ 0, NULL);
+ }
+
+ if (found)
+ list_del(&found->list);
+
+ for (i = 0; i < DUMP_NAME_LEN; i++)
+ efi_name[i] = name[i];
+
+ efivars->ops->set_variable(efi_name, &vendor, PSTORE_EFI_ATTRIBUTES,
+ size, psi->buf);
+
+ spin_unlock(&efivars->lock);
+
+ if (found)
+ efivar_unregister(found);
+
+ if (size)
+ ret = efivar_create_sysfs_entry(efivars,
+ utf16_strsize(efi_name,
+ DUMP_NAME_LEN * 2),
+ efi_name, &vendor);
+
+ *id = part;
+ return ret;
+};
+
+static int efi_pstore_erase(enum pstore_type_id type, u64 id,
+ struct pstore_info *psi)
+{
+ efi_pstore_write(type, 0, &id, (unsigned int)id, 0, psi);
+
+ return 0;
+}
+#else
+static int efi_pstore_open(struct pstore_info *psi)
+{
+ return 0;
+}
+
+static int efi_pstore_close(struct pstore_info *psi)
+{
+ return 0;
+}
+
+static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type,
+ struct timespec *timespec,
+ char **buf, struct pstore_info *psi)
+{
+ return -1;
+}
+
+static int efi_pstore_write(enum pstore_type_id type,
+ enum kmsg_dump_reason reason, u64 *id,
+ unsigned int part, size_t size, struct pstore_info *psi)
+{
+ return 0;
+}
+
+static int efi_pstore_erase(enum pstore_type_id type, u64 id,
+ struct pstore_info *psi)
+{
+ return 0;
+}
+#endif
+
+static struct pstore_info efi_pstore_info = {
+ .owner = THIS_MODULE,
+ .name = "efi",
+ .open = efi_pstore_open,
+ .close = efi_pstore_close,
+ .read = efi_pstore_read,
+ .write = efi_pstore_write,
+ .erase = efi_pstore_erase,
+};
static ssize_t efivar_create(struct file *filp, struct kobject *kobj,
struct bin_attribute *bin_attr,
if (!capable(CAP_SYS_ADMIN))
return -EACCES;
+ if ((new_var->Attributes & ~EFI_VARIABLE_MASK) != 0 ||
+ validate_var(new_var, new_var->Data, new_var->DataSize) == false) {
+ printk(KERN_ERR "efivars: Malformed variable content\n");
+ return -EINVAL;
+ }
+
spin_lock(&efivars->lock);
/*
* Does this variable already exist?
*/
list_for_each_entry_safe(search_efivar, n, &efivars->list, list) {
- strsize1 = utf8_strsize(search_efivar->var.VariableName, 1024);
- strsize2 = utf8_strsize(new_var->VariableName, 1024);
+ strsize1 = utf16_strsize(search_efivar->var.VariableName, 1024);
+ strsize2 = utf16_strsize(new_var->VariableName, 1024);
if (strsize1 == strsize2 &&
!memcmp(&(search_efivar->var.VariableName),
new_var->VariableName, strsize1) &&
/* Create the entry in sysfs. Locking is not required here */
status = efivar_create_sysfs_entry(efivars,
- utf8_strsize(new_var->VariableName,
- 1024),
+ utf16_strsize(new_var->VariableName,
+ 1024),
new_var->VariableName,
&new_var->VendorGuid);
if (status) {
* Does this variable already exist?
*/
list_for_each_entry_safe(search_efivar, n, &efivars->list, list) {
- strsize1 = utf8_strsize(search_efivar->var.VariableName, 1024);
- strsize2 = utf8_strsize(del_var->VariableName, 1024);
+ strsize1 = utf16_strsize(search_efivar->var.VariableName, 1024);
+ strsize2 = utf16_strsize(del_var->VariableName, 1024);
if (strsize1 == strsize2 &&
!memcmp(&(search_efivar->var.VariableName),
del_var->VariableName, strsize1) &&
return 0;
out_free:
- kfree(efivars->new_var);
- efivars->new_var = NULL;
+ kfree(efivars->del_var);
+ efivars->del_var = NULL;
kfree(efivars->new_var);
efivars->new_var = NULL;
return error;
if (error)
unregister_efivars(efivars);
+ efivars->efi_pstore_info = efi_pstore_info;
+
+ efivars->efi_pstore_info.buf = kmalloc(4096, GFP_KERNEL);
+ if (efivars->efi_pstore_info.buf) {
+ efivars->efi_pstore_info.bufsize = 1024;
+ efivars->efi_pstore_info.data = efivars;
+ spin_lock_init(&efivars->efi_pstore_info.buf_lock);
+ pstore_register(&efivars->efi_pstore_info);
+ }
+
out:
kfree(variable_name);
ops.set_variable = efi.set_variable;
ops.get_next_variable = efi.get_next_variable;
error = register_efivars(&__efivars, &ops, efi_kobj);
+ if (error)
+ goto err_put;
/* Don't forget the systab entry */
error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group);
printk(KERN_ERR
"efivars: Sysfs attribute export failed with error %d.\n",
error);
- unregister_efivars(&__efivars);
- kobject_put(efi_kobj);
+ goto err_unregister;
}
+ return 0;
+
+err_unregister:
+ unregister_efivars(&__efivars);
+err_put:
+ kobject_put(efi_kobj);
return error;
}
static void __exit
efivars_exit(void)
{
- unregister_efivars(&__efivars);
- kobject_put(efi_kobj);
+ if (efi_enabled) {
+ unregister_efivars(&__efivars);
+ kobject_put(efi_kobj);
+ }
}
module_init(efivars_init);