diff options
Diffstat (limited to 'lib/efi_loader/efi_variable.c')
| -rw-r--r-- | lib/efi_loader/efi_variable.c | 26 |
1 files changed, 20 insertions, 6 deletions
diff --git a/lib/efi_loader/efi_variable.c b/lib/efi_loader/efi_variable.c index 40f7a0fb10d..d1db7ade0a0 100644 --- a/lib/efi_loader/efi_variable.c +++ b/lib/efi_loader/efi_variable.c @@ -282,11 +282,21 @@ efi_status_t efi_set_variable_int(const u16 *variable_name, } time = var->time; } else { - if (delete || append) - /* - * Trying to delete or to update a non-existent - * variable. - */ + /* + * UEFI specification does not clearly describe the expected + * behavior of append write with data size 0, we follow + * the EDK II reference implementation. + */ + if (append && !data_size) + return EFI_SUCCESS; + + /* + * EFI_VARIABLE_APPEND_WRITE to non-existent variable is accepted + * and new variable is created in EDK II reference implementation. + * We follow it and only check the deletion here. + */ + if (delete) + /* Trying to delete a non-existent variable. */ return EFI_NOT_FOUND; } @@ -329,7 +339,11 @@ efi_status_t efi_set_variable_int(const u16 *variable_name, /* EFI_NOT_FOUND has been handled before */ attributes = var->attr; ret = EFI_SUCCESS; - } else if (append) { + } else if (append && var) { + /* + * data is appended if EFI_VARIABLE_APPEND_WRITE is set and + * variable exists. + */ u16 *old_data = var->name; for (; *old_data; ++old_data) |