Remplacement des tests ofs + len > length par ofs > len - length, pour eviter le debordement lors de l'addition (PR#1229)

git-svn-id: http://caml.inria.fr/svn/ocaml/trunk@4993 f963ae5c-01c2-4b8c-9fe0-0dff7051ff02

1 files changed, 4 insertions, 4 deletions

diff --git a/stdlib/marshal.ml b/stdlib/marshal.ml
index e248c468d..ffe397dec 100644
--- a/stdlib/marshal.ml
+++ b/stdlib/marshal.ml
@@ -26,7 +26,7 @@ external to_buffer_unsafe:
     = "output_value_to_buffer"
 
 let to_buffer buff ofs len v flags =
-  if ofs < 0 || len < 0 || ofs + len > String.length buff
+  if ofs < 0 || len < 0 || ofs > String.length buff - len
   then invalid_arg "Marshal.to_buffer: substring out of bounds"
   else to_buffer_unsafe buff ofs len v flags
 
@@ -36,17 +36,17 @@ external data_size_unsafe: string -> int -> int = "marshal_data_size"
 
 let header_size = 20
 let data_size buff ofs =
-  if ofs < 0 || ofs + header_size > String.length buff
+  if ofs < 0 || ofs > String.length buff - header_size
   then invalid_arg "Marshal.data_size"
   else data_size_unsafe buff ofs
 let total_size buff ofs = header_size + data_size buff ofs
 
 let from_string buff ofs =
-  if ofs < 0 || ofs + header_size > String.length buff
+  if ofs < 0 || ofs > String.length buff - header_size
   then invalid_arg "Marshal.from_size"
   else begin
     let len = data_size_unsafe buff ofs in
-    if ofs + header_size + len > String.length buff
+    if ofs > String.length buff - (header_size + len)
     then invalid_arg "Marshal.from_string"
     else from_string_unsafe buff ofs
   end