diff --git a/libisofs/eltorito.c b/libisofs/eltorito.c
index 41a543a..0fe20ca 100644
--- a/libisofs/eltorito.c
+++ b/libisofs/eltorito.c
@@ -1178,10 +1178,10 @@ int iso_patch_eltoritos(Ecma119Image *t)
     continue;
         original = t->bootsrc[idx]->stream;
         size = (size_t) iso_stream_get_size(original);
-
-        /* >>> BOOT ts B00428 :
-               check whether size is not too large for buffering */;
-
+        if (size > Libisofs_elto_max_patchablE)
+            return ISO_PATCH_OVERSIZED_BOOT;
+        if (iso_stream_get_input_stream(original, 0) != NULL)
+            return ISO_PATCH_FILTERED_BOOT;
         buf = calloc(1, size);
         if (buf == NULL) {
             return ISO_OUT_OF_MEM;
diff --git a/libisofs/eltorito.h b/libisofs/eltorito.h
index 64ce050..7eb1bbb 100644
--- a/libisofs/eltorito.h
+++ b/libisofs/eltorito.h
@@ -168,4 +168,11 @@ int iso_patch_eltoritos(Ecma119Image *t);
 #define Libisofs_grub2_elto_patch_offsT  5
 
 
+/* Maximum size of a boot image which is marked by
+   el_torito_set_isolinux_options() for patching (boot info table,
+   GRUB2 boot info, maybe others).
+*/
+#define Libisofs_elto_max_patchablE      (32 * 1024 * 1024)
+
+
 #endif /* LIBISO_ELTORITO_H */
diff --git a/libisofs/libisofs.h b/libisofs/libisofs.h
index 60d8985..3220ba9 100644
--- a/libisofs/libisofs.h
+++ b/libisofs/libisofs.h
@@ -8312,6 +8312,14 @@ int iso_conv_name_chars(IsoWriteOpts *opts, char *name, size_t name_len,
                                                        (NOTE, HIGH, -409) */
 #define ISO_NOT_REPRODUCIBLE        0xB030FE67
 
+/** May not write boot info into filtered stream of boot image
+                                                       (FAILURE, HIGH, -410) */
+#define ISO_PATCH_FILTERED_BOOT     0xE830FE66
+
+/** Boot image to large to buffer for writing boot info
+                                                       (FAILURE, HIGH, -411) */
+#define ISO_PATCH_OVERSIZED_BOOT    0xE830FE65
+
 
 /* Internal developer note: 
    Place new error codes directly above this comment. 
diff --git a/libisofs/messages.c b/libisofs/messages.c
index 78921b1..18d0d40 100644
--- a/libisofs/messages.c
+++ b/libisofs/messages.c
@@ -531,6 +531,10 @@ const char *iso_error_to_msg(int errcode)
         return "Unreadable file, premature EOF, or failure to seek for interval reader";
     case ISO_NOT_REPRODUCIBLE:
         return "Cannot arrange content of data files in surely reproducible way";
+    case ISO_PATCH_FILTERED_BOOT:
+        return "May not write boot info into filtered stream of boot image";
+    case ISO_PATCH_OVERSIZED_BOOT:
+        return "Boot image to large to buffer for writing boot info";
     default:
         return "Unknown error";
     }