efi_loader: loosen check of parameters of efi_file_open()

The UEFI spec requires that attributes are only set for when
EFI_FILE_MODE_CREATE is set in open_mode.

The SCT tries to read a directory with EFI_FILE_DIRECTORY.

As EDK2 allows this we should not be more strict.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Alexander Graf <agraf@suse.de>

diff --git a/lib/efi_loader/efi_file.c b/lib/efi_loader/efi_file.c
index 9ba7673fb68cc33e868e078b29668cf9ddda5a40..84be0d5818a632a6267503883197fe9d78a284f1 100644 (file)
--- a/lib/efi_loader/efi_file.c
+++ b/lib/efi_loader/efi_file.c
@@ -229,7 +229,16 @@ static efi_status_t EFIAPI efi_file_open(struct efi_file_handle *file,
                ret = EFI_INVALID_PARAMETER;
                goto out;
        }
-       if ((!(open_mode & EFI_FILE_MODE_CREATE) && attributes) ||
+       /*
+        * The UEFI spec requires that attributes are only set in create mode.
+        * The SCT does not care about this and sets EFI_FILE_DIRECTORY in
+        * read mode. EDK2 does not check that attributes are zero if not in
+        * create mode.
+        *
+        * So here we only check attributes in create mode and do not check
+        * that they are zero otherwise.
+        */
+       if ((open_mode & EFI_FILE_MODE_CREATE) &&
            (attributes & (EFI_FILE_READ_ONLY | ~EFI_FILE_VALID_ATTR))) {
                ret = EFI_INVALID_PARAMETER;
                goto out;