[BUG] igmpv3 report bug ?

[BUG] igmpv3 report bug ?

[Jun Zhao]

Hi, David:

When Linux have a interface that is attached with SSM(Source-specific
multicast) and filter mode is EXCLUDE, if the multicast router send
group-and-source specific query to this interface for this group, Linux
respond this query with IS_EX record type.According to RFC 3376 $5.2
Page 24, need to respond this query with IS_IN record type.

+--------+              +--------+
|LINUX   |    < - >     |Router  |    
+--------+              +--------+

This is the step to reappear symptom.

1). LINUX join the SSM with EXCLUDE mode.Conceptually equivalent
IPMulticastListen ( interface, multicast-address,
                          EXCLUDE, source-list(A) )

2). Router send the group-and-source specific query to this interface
for this group. 
Query(multicast-address, source-list(B)).

3). Observe the igmpv3 report that send from LINUX, the respond is the
report with IS_EX record type.  
IS_EX(A)

Below is the action from RFC 3376 $ 5.2 Page 24:

                         set of sources in the
      interface state   pending response record   Current-State Record
      ---------------   -----------------------   --------------------
       EXCLUDE (A)               Query(B)          IS_IN (B-A)

This is linux action

                         set of sources in the
      interface state   pending response record   Current-State Record
      ---------------   -----------------------   --------------------
       EXCLUDE (A)               Query(B)          IS_EX (A)

I find MLDv2 have this symptom too.

Tks.