From ff6af6eede200503c58250821d1285f94039eef7 Mon Sep 17 00:00:00 2001 From: Ilias Apalodimas Date: Wed, 16 Mar 2022 17:13:37 +0200 Subject: [PATCH] efi_loader: Set variable attributes when EFI_BUFFER_TOO_SMALL is returned Starting UEFI Spec 2.8 we must fill in the variable attributes when GetVariable() returns EFI_BUFFER_TOO_SMALL and Attributes is non-NULL. This code was written with 2.7 in mind so let's move the code around a bit and fill in the attributes EFI_BUFFER_TOO_SMALL is returned Signed-off-by: Ilias Apalodimas Reviewed-by: Heinrich Schuchardt --- lib/efi_loader/efi_variable_tee.c | 31 ++++++++++++++++++++----------- 1 file changed, 20 insertions(+), 11 deletions(-) diff --git a/lib/efi_loader/efi_variable_tee.c b/lib/efi_loader/efi_variable_tee.c index 58931c4efd..dfef18435d 100644 --- a/lib/efi_loader/efi_variable_tee.c +++ b/lib/efi_loader/efi_variable_tee.c @@ -368,7 +368,7 @@ efi_status_t efi_get_variable_int(const u16 *variable_name, efi_uintn_t name_size; efi_uintn_t tmp_dsize; u8 *comm_buf = NULL; - efi_status_t ret; + efi_status_t ret, tmp; if (!variable_name || !vendor || !data_size) { ret = EFI_INVALID_PARAMETER; @@ -407,23 +407,32 @@ efi_status_t efi_get_variable_int(const u16 *variable_name, /* Communicate */ ret = mm_communicate(comm_buf, payload_size); - if (ret == EFI_SUCCESS || ret == EFI_BUFFER_TOO_SMALL) { - /* Update with reported data size for trimmed case */ - *data_size = var_acc->data_size; - } - if (ret != EFI_SUCCESS) - goto out; - - ret = get_property_int(variable_name, name_size, vendor, &var_property); - if (ret != EFI_SUCCESS) + if (ret != EFI_SUCCESS && ret != EFI_BUFFER_TOO_SMALL) goto out; + /* Update with reported data size for trimmed case */ + *data_size = var_acc->data_size; + /* + * UEFI > 2.7 needs the attributes set even if the buffer is + * smaller + */ if (attributes) { + tmp = get_property_int(variable_name, name_size, vendor, + &var_property); + if (tmp != EFI_SUCCESS) { + ret = tmp; + goto out; + } *attributes = var_acc->attr; - if (var_property.property & VAR_CHECK_VARIABLE_PROPERTY_READ_ONLY) + if (var_property.property & + VAR_CHECK_VARIABLE_PROPERTY_READ_ONLY) *attributes |= EFI_VARIABLE_READ_ONLY; } + /* return if ret is EFI_BUFFER_TOO_SMALL */ + if (ret != EFI_SUCCESS) + goto out; + if (data) memcpy(data, (u8 *)var_acc->name + var_acc->name_size, var_acc->data_size); -- 2.39.5