capnp.lua: 111: Range is out of bounds

[koolkhel]

Frame 992: 146 bytes on wire (1168 bits), 146 bytes captured (1168 bits) on interface 0
Ethernet II, Src: Tp-LinkT_00:8d:26 (ec:08:6b:00:8d:26), Dst: Apple_7a:3a:bd (ac:bc:32:7a:3a:bd)
Internet Protocol Version 4, Src: xx.xx.xx.xx, Dst: xx.xx.xx.xx
Transmission Control Protocol, Src Port: xxxx, Dst Port: 58047, Seq: 185, Ack: 481, Len: 80
Cap'n Proto RPC Protocol
    Segments: 1
Lua Error: [string "~/.wireshark/plugins/capnp.lua..."]:110: Range is out of bounds
    [Expert Info (Error/Undecoded): Lua Error: [string "~/.wireshark/plugins/capnp.lua..."]:110: Range is out of bounds]
        [Lua Error: [string "~/.wireshark/plugins/capnp.lua..."]:110: Range is out of bounds]
        [Severity level: Error]
        [Group: Undecoded]

Hello! I'm trying to parse a custom Cap'N Proto protocol on the wire. I have compiled schemas with Makefile to lua scripts, they seem to be complete and valid. Yet, I get this message when I try to run Wireshark. Messages go on TCP stream with self-delimiting of Cap'N Proto. Any ideas on how to debug this?

[koolkhel]

It seems like 'size' around those lines sometimes gets to 524304 for my case:

 -- decode segments header
   for i = 1, count do
      local b_size = buf(4 * i, 4)
      local size = b_size:le_uint() * 8
      print(size, count, i)
      segs[i - 1] = data(0, size):tvb()
      seg_tree
         :add(b_size, "Segment:", i - 1, "(", size / 8, "words )")
         :add(data(0, size), "Data (", size, "bytes )")
      data = data(size):tvb()
   end

[MTRNord]

I am seeing similar bugs now around the seg_table_size variable. :/ Any ideas?

[MTRNord]

Ok this seems like its related to packed streams. Using the unpacked version makes it all work.