network-namespace and NETLINK_INET_DIAG - kernel v3.2.39-longterm

network-namespace and NETLINK_INET_DIAG - kernel v3.2.39-longterm

[Dilip Daya]

Hi Eric et al,

Re: Network-namespace and NETLINK_INET_DIAG

=> Kernel v3.2.39-longterm

Within a default/host namespace:
--------------------------------

# strace /bin/ss -pim 
execve("/bin/ss", ["/bin/ss", "-pim"], [/* 28 vars */]) = 0
...
...
socket(PF_NETLINK, SOCK_RAW, 4)         = 3  
sendmsg(3, {msg_name(12)={sa_family=AF_NETLINK, pid=0, groups=00000000},
            msg_iov(1)=[{"L\0\0\0\22\0\1\3@\342\1\0\0\0\0\0\2\0\0\17\0\0
                          \0\0\0\0\0\0\0\0\0\0"..., 76}],
            msg_controllen=0,
            msg_flags=0}, 0) = 76
recvmsg(3, {msg_name(12)={sa_family=AF_NETLINK, pid=0, groups=00000000},
            msg_iov(1)=[{"\344\0\0\0\22\0\2\0@\342\1\0\31|\0\0\2\1\2\0\0
                          \26\353;\300\250\2=088 "..., 8192}],
            msg_controllen=0, msg_flags=0}, 0) = 684
...


# /bin/ss -pim
State       Recv-Q Send-Q   Local Address:Port       Peer Address:Port 
ESTAB       0      0        192.168.2.61:ssh         192.168.2.62:60220
users:(("sshd",7491,3))
mem:(r0,w0,f0,t0) cubic wscale:5,5 rto:216 rtt:18.5/19 ato:40 cwnd:10
 send 6.3Mbps rcv_rtt:4 rcv_space:14480


Within a network-namespace:
---------------------------

# strace /bin/ss -pim 
execve("/bin/ss", ["/bin/ss", "-pim"], [/* 28 vars */]) = 0
...
...
socket(PF_NETLINK, SOCK_RAW, 4)         = 5  
sendmsg(5, {msg_name(12)={sa_family=AF_NETLINK, pid=0, groups=00000000},
            msg_iov(1)=[{"L\0\0\0\22\0\1\3@\342\1\0\0\0\0\0\2\0\0\17\0\0
                          \0\0\0\0\0\0\0\0\0\0"..., 76}],
            msg_controllen=0,
            msg_flags=0}, 0) = -1 ECONNREFUSED (Connection refused)
...


# /bin/ss -pim
State       Recv-Q Send-Q   Local Address:Port     Peer Address:Port   
ESTAB       0      0        192.168.2.61:ssh       192.168.2.62:60220
rto:0.21 ato:0.04 cwnd:10 bidir
users:(("sshd",7491,3))


=> Network namespace (kernel v3.2.39-longterm) not allowing /bin/ss
   missing information from structs tcp_info  and  inet_diag_meminfo.
   This is fixed in kernel v3.6-rc1. Are there identifiable patchsets
   from kernel v3.6-rc1 that can be easily backported to
   kernel v3.2.x-longterm ??


Thanks.
-- 
-DilipD.

Re: network-namespace and NETLINK_INET_DIAG - kernel v3.2.39-longterm

[Eric W. Biederman]

Dilip Daya <dilip.daya@hp.com> writes:

> Hi Eric et al,
>
> Re: Network-namespace and NETLINK_INET_DIAG
>
> => Network namespace (kernel v3.2.39-longterm) not allowing /bin/ss
>    missing information from structs tcp_info  and  inet_diag_meminfo.
>    This is fixed in kernel v3.6-rc1. Are there identifiable patchsets
>    from kernel v3.6-rc1 that can be easily backported to
>    kernel v3.2.x-longterm ??

Possibly.  Certainly the patches that changed this were INET_DIAG
specific.  Take a look in the git history.

Not having a feature implemented is not the same as a bug.  So I don't
expect anyone is in a rush to backport this.

Eric