diff --git a/src/add-ons/kernel/file_systems/udf/Icb.cpp b/src/add-ons/kernel/file_systems/udf/Icb.cpp
index fedf284a53..a4dda56040 100644
--- a/src/add-ons/kernel/file_systems/udf/Icb.cpp
+++ b/src/add-ons/kernel/file_systems/udf/Icb.cpp
@@ -57,9 +57,9 @@ Icb::Read(off_t pos, void *buffer, size_t *length, uint32 *block)
 	DEBUG_INIT_ETC(CF_PUBLIC | CF_HIGH_VOLUME, "Icb",
 	               ("pos: %lld, buffer: %p, length: (%p)->%ld", pos, buffer, length, (length ? *length : 0)));
 
-	if (!buffer || !length)
-		RETURN(B_BAD_VALUE);
-		
+	if (!buffer || !length || pos < 0)
+		RETURN(B_BAD_VALUE);		
+	
 	if (uint64(pos) >= Length()) {
 		*length = 0;
 		return B_OK;