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path: root/drivers/firmware/efi
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-rw-r--r--drivers/firmware/efi/efi.c1
-rw-r--r--drivers/firmware/efi/vars.c733
2 files changed, 1 insertions, 733 deletions
diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
index 7f06065d3eb0..e4080ad96089 100644
--- a/drivers/firmware/efi/efi.c
+++ b/drivers/firmware/efi/efi.c
@@ -899,6 +899,7 @@ int efi_status_to_err(efi_status_t status)
return err;
}
+EXPORT_SYMBOL_GPL(efi_status_to_err);
static DEFINE_SPINLOCK(efi_mem_reserve_persistent_lock);
static struct linux_efi_memreserve *efi_memreserve_root __ro_after_init;
diff --git a/drivers/firmware/efi/vars.c b/drivers/firmware/efi/vars.c
index cafc128a5774..dd74d2ad3184 100644
--- a/drivers/firmware/efi/vars.c
+++ b/drivers/firmware/efi/vars.c
@@ -6,298 +6,20 @@
* Copyright (C) 2004 Intel Corporation <matthew.e.tolentino@intel.com>
*/
-#include <linux/capability.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/init.h>
-#include <linux/mm.h>
#include <linux/module.h>
#include <linux/string.h>
#include <linux/smp.h>
#include <linux/efi.h>
-#include <linux/sysfs.h>
-#include <linux/device.h>
-#include <linux/slab.h>
-#include <linux/ctype.h>
#include <linux/ucs2_string.h>
/* Private pointer to registered efivars */
static struct efivars *__efivars;
-/*
- * efivars_lock protects three things:
- * 1) efivarfs_list and efivars_sysfs_list
- * 2) ->ops calls
- * 3) (un)registration of __efivars
- */
static DEFINE_SEMAPHORE(efivars_lock);
-static bool
-validate_device_path(efi_char16_t *var_name, 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(efi_char16_t *var_name, int match, u8 *buffer,
- unsigned long len)
-{
- /* An array of 16-bit integers */
- if ((len % 2) != 0)
- return false;
-
- return true;
-}
-
-static bool
-validate_load_option(efi_char16_t *var_name, int match, u8 *buffer,
- unsigned long len)
-{
- u16 filepathlength;
- int i, desclength = 0, namelen;
-
- namelen = ucs2_strnlen(var_name, EFI_VAR_NAME_LEN);
-
- /* Either "Boot" or "Driver" followed by four digits of hex */
- for (i = match; i < match+4; i++) {
- if (var_name[i] > 127 ||
- hex_to_bin(var_name[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 = ucs2_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_name, match, buffer + desclength + 6,
- filepathlength);
-}
-
-static bool
-validate_uint16(efi_char16_t *var_name, int match, u8 *buffer,
- unsigned long len)
-{
- /* A single 16-bit integer */
- if (len != 2)
- return false;
-
- return true;
-}
-
-static bool
-validate_ascii_string(efi_char16_t *var_name, 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 {
- efi_guid_t vendor;
- char *name;
- bool (*validate)(efi_char16_t *var_name, int match, u8 *data,
- unsigned long len);
-};
-
-/*
- * This is the list of variables we need to validate, as well as the
- * whitelist for what we think is safe not to default to immutable.
- *
- * If it has a validate() method that's not NULL, it'll go into the
- * validation routine. If not, it is assumed valid, but still used for
- * whitelisting.
- *
- * Note that it's sorted by {vendor,name}, but globbed names must come after
- * any other name with the same prefix.
- */
-static const struct variable_validate variable_validate[] = {
- { EFI_GLOBAL_VARIABLE_GUID, "BootNext", validate_uint16 },
- { EFI_GLOBAL_VARIABLE_GUID, "BootOrder", validate_boot_order },
- { EFI_GLOBAL_VARIABLE_GUID, "Boot*", validate_load_option },
- { EFI_GLOBAL_VARIABLE_GUID, "DriverOrder", validate_boot_order },
- { EFI_GLOBAL_VARIABLE_GUID, "Driver*", validate_load_option },
- { EFI_GLOBAL_VARIABLE_GUID, "ConIn", validate_device_path },
- { EFI_GLOBAL_VARIABLE_GUID, "ConInDev", validate_device_path },
- { EFI_GLOBAL_VARIABLE_GUID, "ConOut", validate_device_path },
- { EFI_GLOBAL_VARIABLE_GUID, "ConOutDev", validate_device_path },
- { EFI_GLOBAL_VARIABLE_GUID, "ErrOut", validate_device_path },
- { EFI_GLOBAL_VARIABLE_GUID, "ErrOutDev", validate_device_path },
- { EFI_GLOBAL_VARIABLE_GUID, "Lang", validate_ascii_string },
- { EFI_GLOBAL_VARIABLE_GUID, "OsIndications", NULL },
- { EFI_GLOBAL_VARIABLE_GUID, "PlatformLang", validate_ascii_string },
- { EFI_GLOBAL_VARIABLE_GUID, "Timeout", validate_uint16 },
- { LINUX_EFI_CRASH_GUID, "*", NULL },
- { NULL_GUID, "", NULL },
-};
-
-/*
- * Check if @var_name matches the pattern given in @match_name.
- *
- * @var_name: an array of @len non-NUL characters.
- * @match_name: a NUL-terminated pattern string, optionally ending in "*". A
- * final "*" character matches any trailing characters @var_name,
- * including the case when there are none left in @var_name.
- * @match: on output, the number of non-wildcard characters in @match_name
- * that @var_name matches, regardless of the return value.
- * @return: whether @var_name fully matches @match_name.
- */
-static bool
-variable_matches(const char *var_name, size_t len, const char *match_name,
- int *match)
-{
- for (*match = 0; ; (*match)++) {
- char c = match_name[*match];
-
- switch (c) {
- case '*':
- /* Wildcard in @match_name means we've matched. */
- return true;
-
- case '\0':
- /* @match_name has ended. Has @var_name too? */
- return (*match == len);
-
- default:
- /*
- * We've reached a non-wildcard char in @match_name.
- * Continue only if there's an identical character in
- * @var_name.
- */
- if (*match < len && c == var_name[*match])
- continue;
- return false;
- }
- }
-}
-
-bool
-efivar_validate(efi_guid_t vendor, efi_char16_t *var_name, u8 *data,
- unsigned long data_size)
-{
- int i;
- unsigned long utf8_size;
- u8 *utf8_name;
-
- utf8_size = ucs2_utf8size(var_name);
- utf8_name = kmalloc(utf8_size + 1, GFP_KERNEL);
- if (!utf8_name)
- return false;
-
- ucs2_as_utf8(utf8_name, var_name, utf8_size);
- utf8_name[utf8_size] = '\0';
-
- for (i = 0; variable_validate[i].name[0] != '\0'; i++) {
- const char *name = variable_validate[i].name;
- int match = 0;
-
- if (efi_guidcmp(vendor, variable_validate[i].vendor))
- continue;
-
- if (variable_matches(utf8_name, utf8_size+1, name, &match)) {
- if (variable_validate[i].validate == NULL)
- break;
- kfree(utf8_name);
- return variable_validate[i].validate(var_name, match,
- data, data_size);
- }
- }
- kfree(utf8_name);
- return true;
-}
-EXPORT_SYMBOL_GPL(efivar_validate);
-
-bool
-efivar_variable_is_removable(efi_guid_t vendor, const char *var_name,
- size_t len)
-{
- int i;
- bool found = false;
- int match = 0;
-
- /*
- * Check if our variable is in the validated variables list
- */
- for (i = 0; variable_validate[i].name[0] != '\0'; i++) {
- if (efi_guidcmp(variable_validate[i].vendor, vendor))
- continue;
-
- if (variable_matches(var_name, len,
- variable_validate[i].name, &match)) {
- found = true;
- break;
- }
- }
-
- /*
- * If it's in our list, it is removable.
- */
- return found;
-}
-EXPORT_SYMBOL_GPL(efivar_variable_is_removable);
-
efi_status_t check_var_size(u32 attributes, unsigned long size)
{
const struct efivar_operations *fops;
@@ -324,461 +46,6 @@ efi_status_t check_var_size_nonblocking(u32 attributes, unsigned long size)
}
EXPORT_SYMBOL_NS_GPL(check_var_size_nonblocking, EFIVAR);
-static bool variable_is_present(efi_char16_t *variable_name, efi_guid_t *vendor,
- struct list_head *head)
-{
- struct efivar_entry *entry, *n;
- unsigned long strsize1, strsize2;
- bool found = false;
-
- strsize1 = ucs2_strsize(variable_name, 1024);
- list_for_each_entry_safe(entry, n, head, list) {
- strsize2 = ucs2_strsize(entry->var.VariableName, 1024);
- if (strsize1 == strsize2 &&
- !memcmp(variable_name, &(entry->var.VariableName),
- strsize2) &&
- !efi_guidcmp(entry->var.VendorGuid,
- *vendor)) {
- found = true;
- break;
- }
- }
- return found;
-}
-
-/*
- * Returns the size of variable_name, in bytes, including the
- * terminating NULL character, or variable_name_size if no NULL
- * character is found among the first variable_name_size bytes.
- */
-static unsigned long var_name_strnsize(efi_char16_t *variable_name,
- unsigned long variable_name_size)
-{
- unsigned long len;
- efi_char16_t c;
-
- /*
- * The variable name is, by definition, a NULL-terminated
- * string, so make absolutely sure that variable_name_size is
- * the value we expect it to be. If not, return the real size.
- */
- for (len = 2; len <= variable_name_size; len += sizeof(c)) {
- c = variable_name[(len / sizeof(c)) - 1];
- if (!c)
- break;
- }
-
- return min(len, variable_name_size);
-}
-
-/*
- * Print a warning when duplicate EFI variables are encountered and
- * disable the sysfs workqueue since the firmware is buggy.
- */
-static void dup_variable_bug(efi_char16_t *str16, efi_guid_t *vendor_guid,
- unsigned long len16)
-{
- size_t i, len8 = len16 / sizeof(efi_char16_t);
- char *str8;
-
- str8 = kzalloc(len8, GFP_KERNEL);
- if (!str8)
- return;
-
- for (i = 0; i < len8; i++)
- str8[i] = str16[i];
-
- printk(KERN_WARNING "efivars: duplicate variable: %s-%pUl\n",
- str8, vendor_guid);
- kfree(str8);
-}
-
-/**
- * efivar_init - build the initial list of EFI variables
- * @func: callback function to invoke for every variable
- * @data: function-specific data to pass to @func
- * @duplicates: error if we encounter duplicates on @head?
- * @head: initialised head of variable list
- *
- * Get every EFI variable from the firmware and invoke @func. @func
- * should call efivar_entry_add() to build the list of variables.
- *
- * Returns 0 on success, or a kernel error code on failure.
- */
-int efivar_init(int (*func)(efi_char16_t *, efi_guid_t, unsigned long, void *),
- void *data, bool duplicates, struct list_head *head)
-{
- unsigned long variable_name_size = 1024;
- efi_char16_t *variable_name;
- efi_status_t status;
- efi_guid_t vendor_guid;
- int err = 0;
-
- variable_name = kzalloc(variable_name_size, GFP_KERNEL);
- if (!variable_name) {
- printk(KERN_ERR "efivars: Memory allocation failed.\n");
- return -ENOMEM;
- }
-
- err = efivar_lock();
- if (err)
- goto free;
-
- /*
- * Per EFI spec, the maximum storage allocated for both
- * the variable name and variable data is 1024 bytes.
- */
-
- do {
- variable_name_size = 1024;
-
- status = efivar_get_next_variable(&variable_name_size,
- variable_name,
- &vendor_guid);
- switch (status) {
- case EFI_SUCCESS:
- variable_name_size = var_name_strnsize(variable_name,
- variable_name_size);
-
- /*
- * Some firmware implementations return the
- * same variable name on multiple calls to
- * get_next_variable(). Terminate the loop
- * immediately as there is no guarantee that
- * we'll ever see a different variable name,
- * and may end up looping here forever.
- */
- if (duplicates &&
- variable_is_present(variable_name, &vendor_guid,
- head)) {
- dup_variable_bug(variable_name, &vendor_guid,
- variable_name_size);
- status = EFI_NOT_FOUND;
- } else {
- err = func(variable_name, vendor_guid,
- variable_name_size, data);
- if (err)
- status = EFI_NOT_FOUND;
- }
- break;
- case EFI_UNSUPPORTED:
- err = -EOPNOTSUPP;
- status = EFI_NOT_FOUND;
- break;
- case EFI_NOT_FOUND:
- break;
- default:
- printk(KERN_WARNING "efivars: get_next_variable: status=%lx\n",
- status);
- status = EFI_NOT_FOUND;
- break;
- }
-
- } while (status != EFI_NOT_FOUND);
-
- efivar_unlock();
-free:
- kfree(variable_name);
-
- return err;
-}
-EXPORT_SYMBOL_GPL(efivar_init);
-
-/**
- * efivar_entry_add - add entry to variable list
- * @entry: entry to add to list
- * @head: list head
- *
- * Returns 0 on success, or a kernel error code on failure.
- */
-int efivar_entry_add(struct efivar_entry *entry, struct list_head *head)
-{
- int err;
-
- err = efivar_lock();
- if (err)
- return err;
- list_add(&entry->list, head);
- efivar_unlock();
-
- return 0;
-}
-EXPORT_SYMBOL_GPL(efivar_entry_add);
-
-/**
- * __efivar_entry_add - add entry to variable list
- * @entry: entry to add to list
- * @head: list head
- */
-void __efivar_entry_add(struct efivar_entry *entry, struct list_head *head)
-{
- list_add(&entry->list, head);
-}
-EXPORT_SYMBOL_GPL(__efivar_entry_add);
-
-/**
- * efivar_entry_remove - remove entry from variable list
- * @entry: entry to remove from list
- */
-void efivar_entry_remove(struct efivar_entry *entry)
-{
- list_del(&entry->list);
-}
-EXPORT_SYMBOL_GPL(efivar_entry_remove);
-
-/*
- * efivar_entry_list_del_unlock - remove entry from variable list
- * @entry: entry to remove
- *
- * Remove @entry from the variable list and release the list lock.
- *
- * NOTE: slightly weird locking semantics here - we expect to be
- * called with the efivars lock already held, and we release it before
- * returning. This is because this function is usually called after
- * set_variable() while the lock is still held.
- */
-static void efivar_entry_list_del_unlock(struct efivar_entry *entry)
-{
- list_del(&entry->list);
- efivar_unlock();
-}
-
-/**
- * efivar_entry_delete - delete variable and remove entry from list
- * @entry: entry containing variable to delete
- *
- * Delete the variable from the firmware and remove @entry from the
- * variable list. It is the caller's responsibility to free @entry
- * once we return.
- *
- * Returns 0 on success, -EINTR if we can't grab the semaphore,
- * converted EFI status code if set_variable() fails.
- */
-int efivar_entry_delete(struct efivar_entry *entry)
-{
- efi_status_t status;
- int err;
-
- err = efivar_lock();
- if (err)
- return err;
-
- status = efivar_set_variable_locked(entry->var.VariableName,
- &entry->var.VendorGuid,
- 0, 0, NULL, false);
- if (!(status == EFI_SUCCESS || status == EFI_NOT_FOUND)) {
- efivar_unlock();
- return efi_status_to_err(status);
- }
-
- efivar_entry_list_del_unlock(entry);
- return 0;
-}
-EXPORT_SYMBOL_GPL(efivar_entry_delete);
-
-/**
- * efivar_entry_size - obtain the size of a variable
- * @entry: entry for this variable
- * @size: location to store the variable's size
- */
-int efivar_entry_size(struct efivar_entry *entry, unsigned long *size)
-{
- efi_status_t status;
- int err;
-
- *size = 0;
-
- err = efivar_lock();
- if (err)
- return err;
-
- status = efivar_get_variable(entry->var.VariableName,
- &entry->var.VendorGuid, NULL, size, NULL);
- efivar_unlock();
-
- if (status != EFI_BUFFER_TOO_SMALL)
- return efi_status_to_err(status);
-
- return 0;
-}
-EXPORT_SYMBOL_GPL(efivar_entry_size);
-
-/**
- * __efivar_entry_get - call get_variable()
- * @entry: read data for this variable
- * @attributes: variable attributes
- * @size: size of @data buffer
- * @data: buffer to store variable data
- *
- * The caller MUST hold the efivar lock when calling this function.
- */
-int __efivar_entry_get(struct efivar_entry *entry, u32 *attributes,
- unsigned long *size, void *data)
-{
- efi_status_t status;
-
- status = efivar_get_variable(entry->var.VariableName,
- &entry->var.VendorGuid,
- attributes, size, data);
-
- return efi_status_to_err(status);
-}
-EXPORT_SYMBOL_GPL(__efivar_entry_get);
-
-/**
- * efivar_entry_get - call get_variable()
- * @entry: read data for this variable
- * @attributes: variable attributes
- * @size: size of @data buffer
- * @data: buffer to store variable data
- */
-int efivar_entry_get(struct efivar_entry *entry, u32 *attributes,
- unsigned long *size, void *data)
-{
- int err;
-
- err = efivar_lock();
- if (err)
- return err;
- err = __efivar_entry_get(entry, attributes, size, data);
- efivar_unlock();
-
- return err;
-}
-EXPORT_SYMBOL_GPL(efivar_entry_get);
-
-/**
- * efivar_entry_set_get_size - call set_variable() and get new size (atomic)
- * @entry: entry containing variable to set and get
- * @attributes: attributes of variable to be written
- * @size: size of data buffer
- * @data: buffer containing data to write
- * @set: did the set_variable() call succeed?
- *
- * This is a pretty special (complex) function. See efivarfs_file_write().
- *
- * Atomically call set_variable() for @entry and if the call is
- * successful, return the new size of the variable from get_variable()
- * in @size. The success of set_variable() is indicated by @set.
- *
- * Returns 0 on success, -EINVAL if the variable data is invalid,
- * -ENOSPC if the firmware does not have enough available space, or a
- * converted EFI status code if either of set_variable() or
- * get_variable() fail.
- *
- * If the EFI variable does not exist when calling set_variable()
- * (EFI_NOT_FOUND), @entry is removed from the variable list.
- */
-int efivar_entry_set_get_size(struct efivar_entry *entry, u32 attributes,
- unsigned long *size, void *data, bool *set)
-{
- efi_char16_t *name = entry->var.VariableName;
- efi_guid_t *vendor = &entry->var.VendorGuid;
- efi_status_t status;
- int err;
-
- *set = false;
-
- if (efivar_validate(*vendor, name, data, *size) == false)
- return -EINVAL;
-
- /*
- * The lock here protects the get_variable call, the conditional
- * set_variable call, and removal of the variable from the efivars
- * list (in the case of an authenticated delete).
- */
- err = efivar_lock();
- if (err)
- return err;
-
- /*
- * Ensure that the available space hasn't shrunk below the safe level
- */
- status = check_var_size(attributes, *size + ucs2_strsize(name, 1024));
- if (status != EFI_SUCCESS) {
- if (status != EFI_UNSUPPORTED) {
- err = efi_status_to_err(status);
- goto out;
- }
-
- if (*size > 65536) {
- err = -ENOSPC;
- goto out;
- }
- }
-
- status = efivar_set_variable_locked(name, vendor, attributes, *size,
- data, false);
- if (status != EFI_SUCCESS) {
- err = efi_status_to_err(status);
- goto out;
- }
-
- *set = true;
-
- /*
- * Writing to the variable may have caused a change in size (which
- * could either be an append or an overwrite), or the variable to be
- * deleted. Perform a GetVariable() so we can tell what actually
- * happened.
- */
- *size = 0;
- status = efivar_get_variable(entry->var.VariableName,
- &entry->var.VendorGuid,
- NULL, size, NULL);
-
- if (status == EFI_NOT_FOUND)
- efivar_entry_list_del_unlock(entry);
- else
- efivar_unlock();
-
- if (status && status != EFI_BUFFER_TOO_SMALL)
- return efi_status_to_err(status);
-
- return 0;
-
-out:
- efivar_unlock();
- return err;
-
-}
-EXPORT_SYMBOL_GPL(efivar_entry_set_get_size);
-
-/**
- * efivar_entry_iter - iterate over variable list
- * @func: callback function
- * @head: head of variable list
- * @data: function-specific data to pass to callback
- *
- * Iterate over the list of EFI variables and call @func with every
- * entry on the list. It is safe for @func to remove entries in the
- * list via efivar_entry_delete() while iterating.
- *
- * Some notes for the callback function:
- * - a non-zero return value indicates an error and terminates the loop
- * - @func is called from atomic context
- */
-int efivar_entry_iter(int (*func)(struct efivar_entry *, void *),
- struct list_head *head, void *data)
-{
- struct efivar_entry *entry, *n;
- int err = 0;
-
- err = efivar_lock();
- if (err)
- return err;
-
- list_for_each_entry_safe(entry, n, head, list) {
- err = func(entry, data);
- if (err)
- break;
- }
- efivar_unlock();
-
- return err;
-}
-EXPORT_SYMBOL_GPL(efivar_entry_iter);
-
/**
* efivars_kobject - get the kobject for the registered efivars
*