Wrong mroute entry with IGMP report

[anlancs]

The configuration: (eth0's ip is 100.1.1.217, and must be with RP configuration.)

ip pim rp 143.143.143.143 239.0.0.0/8
interface eth0                                                                                                                                                           
 ip igmp                                   
 ip igmp join 239.2.1.1 200.1.1.1  <- "ip igmp join 239.2.1.1" also have this issue.
 ip igmp version 2                 <- "igmp version" doesn't affect this issue.       
 ip pim                                    
exit                                       
  

Then, an unexpected mroute ouccurs:

# do show ip mroute                                                              
IP Multicast Routing Table                                                            
Flags: S - Sparse, C - Connected, P - Pruned                                          
       R - SGRpt Pruned, F - Register flag, T - SPT-bit set                           
 Source       Group      Flags  Proto  Input    Output  TTL  Uptime    
 100.1.1.217  239.2.1.1  SFT    PIM    eth0  pimreg  1    00:59:51  

It means the IGMP report packets were wrongly regarded as data traffic, so the unexpected <S,G> entry is created.

In pim_mroute_msg(), there are packets (src is 100.1.1.217, dst is 239.2.1.1) which ip_hdr->ip_p is 0, not IGMPv2 protocol!

Please help check it, thanks!

[riw777]

what version is this? can you make certain you're on master?

[anlancs]

On stable 8.5.3.

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