v2 correctly checks the guid for validation *as well as* attribute whitelisting. v3 moves the sorting of variable_validate here and adds a comment about it. Signed-off-by: Peter Jones <pjones@xxxxxxxxxx> Tested-by: Lee, Chun-Yi <jlee@xxxxxxxx> Acked-by: Matthew Garrett <mjg59@xxxxxxxxxx> --- drivers/firmware/efi/efivars.c | 5 ++-- drivers/firmware/efi/vars.c | 52 +++++++++++++++++++++++++++--------------- include/linux/efi.h | 3 ++- 3 files changed, 38 insertions(+), 22 deletions(-) diff --git a/drivers/firmware/efi/efivars.c b/drivers/firmware/efi/efivars.c index cd53c4d..e0b1e37 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 36c5a6e..0fc9194 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 len) +efivar_validate(efi_guid_t vendor, efi_char16_t *var_name, u8 *data, + unsigned long len) { int i; unsigned long utf8_size; @@ -202,9 +213,12 @@ efivar_validate(efi_char16_t *var_name, u8 *data, unsigned long len) ucs2_as_utf8(utf8_name, var_name, len); - 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]; @@ -861,7 +875,7 @@ 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 569b5a8..52444fd 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 len); extern struct work_struct efivar_work; void efivar_run_worker(void); -- 2.5.0 -- To unsubscribe from this list: send the line "unsubscribe linux-efi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html