diff options
-rw-r--r-- | tools/ocaml/libs/xb/partial.ml | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/tools/ocaml/libs/xb/partial.ml b/tools/ocaml/libs/xb/partial.ml index 3558889589..d4d1c7bdec 100644 --- a/tools/ocaml/libs/xb/partial.ml +++ b/tools/ocaml/libs/xb/partial.ml @@ -27,8 +27,15 @@ external header_size: unit -> int = "stub_header_size" external header_of_string_internal: string -> int * int * int * int = "stub_header_of_string" +let xenstore_payload_max = 4096 (* xen/include/public/io/xs_wire.h *) + let of_string s = let tid, rid, opint, dlen = header_of_string_internal s in + (* A packet which is bigger than xenstore_payload_max is illegal. + This will leave the guest connection is a bad state and will + be hard to recover from without restarting the connection + (ie rebooting the guest) *) + let dlen = min xenstore_payload_max dlen in { tid = tid; rid = rid; @@ -38,6 +45,7 @@ let of_string s = } let append pkt s sz = + if pkt.len > 4096 then failwith "Buffer.add: cannot grow buffer"; Buffer.add_string pkt.buf (String.sub s 0 sz) let to_complete pkt = |