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Wireshark-dev: Re: [Wireshark-dev] malformed packet

From: Hadriel Kaplan <HKaplan@xxxxxxxxxxxxxx>
Date: Thu, 28 Feb 2013 07:43:19 +0000
Wireshark's SIP dissector is throwing an error on the RAck header field method name.
It shouldn't, because the message's header is correctly formed, but there's a bug in packet-sip.c:
for case POS_RACK, when it goes to add the method name, it's using '(int)linelen-sub_value_offset' for the length argument to proto_tree_add_item(),
but should be using '(int)value_len-sub_value_offset'.

patch:
Index: epan/dissectors/packet-sip.c
===================================================================
--- epan/dissectors/packet-sip.c	(revision 47899)
+++ epan/dissectors/packet-sip.c	(working copy)
@@ -2734,7 +2734,7 @@
 						{
 							proto_tree_add_item(rack_tree, hf_sip_rack_cseq_method, tvb,
 							                    value_offset + sub_value_offset,
-							                    (int)linelen-sub_value_offset, ENC_ASCII|ENC_NA);
+							                    (int)value_len-sub_value_offset, ENC_ASCII|ENC_NA);
 						}
 
 						break;


-hadriel


On Feb 28, 2013, at 1:21 AM, Lohith HS <lohith.hs@xxxxxxxxxxxxxxxxxx> wrote:

> Hi ,
> 
>    I am getting malformed packet in SIP message(PRACK) in wireshark 1.6.7 version.
>    But if i see the same capture in 0.9 version ,  there is no malformed packet issue.
>    Pls can anyone tell me what is the issue.i have attached the capture file.
> 
> 
> Thanks,
> Lohith
> <sip_prack_malformed.pcap >___________________________________________________________________________
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