From e0d64e6a880e64545ad7d55786aa84ab76bac475 Mon Sep 17 00:00:00 2001 From: Peter Jones Date: Mon, 8 Feb 2016 14:48:12 -0500 Subject: efi: Use ucs2_as_utf8 in efivarfs instead of open coding a bad version Translate EFI's UCS-2 variable names to UTF-8 instead of just assuming all variable names fit in ASCII. Signed-off-by: Peter Jones Acked-by: Matthew Garrett Tested-by: Lee, Chun-Yi Signed-off-by: Matt Fleming --- drivers/firmware/efi/efivars.c | 30 +++++++++++------------------- 1 file changed, 11 insertions(+), 19 deletions(-) (limited to 'drivers/firmware/efi/efivars.c') diff --git a/drivers/firmware/efi/efivars.c b/drivers/firmware/efi/efivars.c index 756eca8c4cf8..f4ff8abc5f3e 100644 --- a/drivers/firmware/efi/efivars.c +++ b/drivers/firmware/efi/efivars.c @@ -540,38 +540,30 @@ static ssize_t efivar_delete(struct file *filp, struct kobject *kobj, static int efivar_create_sysfs_entry(struct efivar_entry *new_var) { - int i, short_name_size; + int short_name_size; char *short_name; - unsigned long variable_name_size; - efi_char16_t *variable_name; + unsigned long utf8_name_size; + efi_char16_t *variable_name = new_var->var.VariableName; int ret; - variable_name = new_var->var.VariableName; - variable_name_size = ucs2_strlen(variable_name) * sizeof(efi_char16_t); - /* - * Length of the variable bytes in ASCII, plus the '-' separator, + * Length of the variable bytes in UTF8, plus the '-' separator, * plus the GUID, plus trailing NUL */ - short_name_size = variable_name_size / sizeof(efi_char16_t) - + 1 + EFI_VARIABLE_GUID_LEN + 1; - - short_name = kzalloc(short_name_size, GFP_KERNEL); + utf8_name_size = ucs2_utf8size(variable_name); + short_name_size = utf8_name_size + 1 + EFI_VARIABLE_GUID_LEN + 1; + short_name = kmalloc(short_name_size, GFP_KERNEL); if (!short_name) return -ENOMEM; - /* Convert Unicode to normal chars (assume top bits are 0), - ala UTF-8 */ - for (i=0; i < (int)(variable_name_size / sizeof(efi_char16_t)); i++) { - short_name[i] = variable_name[i] & 0xFF; - } + ucs2_as_utf8(short_name, variable_name, short_name_size); + /* This is ugly, but necessary to separate one vendor's private variables from another's. */ - - *(short_name + strlen(short_name)) = '-'; + short_name[utf8_name_size] = '-'; efi_guid_to_str(&new_var->var.VendorGuid, - short_name + strlen(short_name)); + short_name + utf8_name_size + 1); new_var->kobj.kset = efivars_kset; -- cgit v1.2.3 From 8282f5d9c17fe15a9e658c06e3f343efae1a2a2f Mon Sep 17 00:00:00 2001 From: Peter Jones Date: Mon, 8 Feb 2016 14:48:14 -0500 Subject: efi: Make our variable validation list include the guid All the variables in this list so far are defined to be in the global namespace in the UEFI spec, so this just further ensures we're validating the variables we think we are. Including the guid for entries will become more important in future patches when we decide whether or not to allow deletion of variables based on presence in this list. Signed-off-by: Peter Jones Tested-by: Lee, Chun-Yi Acked-by: Matthew Garrett Signed-off-by: Matt Fleming --- drivers/firmware/efi/efivars.c | 5 ++-- drivers/firmware/efi/vars.c | 52 +++++++++++++++++++++++++++--------------- include/linux/efi.h | 3 ++- 3 files changed, 38 insertions(+), 22 deletions(-) (limited to 'drivers/firmware/efi/efivars.c') diff --git a/drivers/firmware/efi/efivars.c b/drivers/firmware/efi/efivars.c index f4ff8abc5f3e..10e6774ab2a2 100644 --- a/drivers/firmware/efi/efivars.c +++ b/drivers/firmware/efi/efivars.c @@ -221,7 +221,7 @@ sanity_check(struct efi_variable *var, efi_char16_t *name, efi_guid_t vendor, } if ((attributes & ~EFI_VARIABLE_MASK) != 0 || - efivar_validate(name, data, size) == false) { + efivar_validate(vendor, name, data, size) == false) { printk(KERN_ERR "efivars: Malformed variable content\n"); return -EINVAL; } @@ -447,7 +447,8 @@ static ssize_t efivar_create(struct file *filp, struct kobject *kobj, } if ((attributes & ~EFI_VARIABLE_MASK) != 0 || - efivar_validate(name, data, size) == false) { + efivar_validate(new_var->VendorGuid, name, data, + size) == false) { printk(KERN_ERR "efivars: Malformed variable content\n"); return -EINVAL; } diff --git a/drivers/firmware/efi/vars.c b/drivers/firmware/efi/vars.c index 5c5fde3e6c37..9a53da21e7b6 100644 --- a/drivers/firmware/efi/vars.c +++ b/drivers/firmware/efi/vars.c @@ -165,31 +165,42 @@ validate_ascii_string(efi_char16_t *var_name, int match, u8 *buffer, } 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. + * + * If it has a validate() method that's not NULL, it'll go into the + * validation routine. If not, it is assumed valid. + * + * 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[] = { - { "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 }, + { 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, "PlatformLang", validate_ascii_string }, + { EFI_GLOBAL_VARIABLE_GUID, "Timeout", validate_uint16 }, + { NULL_GUID, "", NULL }, }; bool -efivar_validate(efi_char16_t *var_name, u8 *data, unsigned long data_size) +efivar_validate(efi_guid_t vendor, efi_char16_t *var_name, u8 *data, + unsigned long data_size) { int i; unsigned long utf8_size; @@ -203,9 +214,12 @@ efivar_validate(efi_char16_t *var_name, u8 *data, unsigned long data_size) ucs2_as_utf8(utf8_name, var_name, utf8_size); utf8_name[utf8_size] = '\0'; - for (i = 0; variable_validate[i].validate != NULL; i++) { + for (i = 0; variable_validate[i].name[0] != '\0'; i++) { const char *name = variable_validate[i].name; - int match; + int match = 0; + + if (efi_guidcmp(vendor, variable_validate[i].vendor)) + continue; for (match = 0; ; match++) { char c = name[match]; @@ -862,7 +876,7 @@ int efivar_entry_set_get_size(struct efivar_entry *entry, u32 attributes, *set = false; - if (efivar_validate(name, data, *size) == false) + if (efivar_validate(*vendor, name, data, *size) == false) return -EINVAL; /* diff --git a/include/linux/efi.h b/include/linux/efi.h index 569b5a866bb1..16ca611aabc8 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -1199,7 +1199,8 @@ int efivar_entry_iter(int (*func)(struct efivar_entry *, void *), struct efivar_entry *efivar_entry_find(efi_char16_t *name, efi_guid_t guid, struct list_head *head, bool remove); -bool efivar_validate(efi_char16_t *var_name, u8 *data, unsigned long len); +bool efivar_validate(efi_guid_t vendor, efi_char16_t *var_name, u8 *data, + unsigned long data_size); extern struct work_struct efivar_work; void efivar_run_worker(void); -- cgit v1.2.3