Possible problem in sctp_getsockopt_peer_addrs (and similar functions)

[Sebastien Decugis <sdecugis@nict.go.jp>]

Hello list,

I think there is a problem in sctp_getsockopt_peer_addrs function in
net/sctp/socket.c.

I run into the problem when I call sctp_getpaddrs in userland, with a
buffer containing IPv4 address followed by IPv6. The address buffer I
receive cannot be parsed. After correctly reading the first address, I
am not aligned correctly when I move my pointer forward by sizeof(struct
sockaddr_in), to read the next address. I am not using mapped addresses.
I believe the source of the problem being the following code:

list_for_each_entry(from, &asoc->peer.transport_addr_list,
                              transports) {
    memcpy(&temp, &from->ipaddr, sizeof(temp));
    sctp_get_pf_specific(sk->sk_family)->addr_v4map(sp, &temp);
    addrlen = sctp_get_af_specific(sk->sk_family)->sockaddr_len;

In this last line, shouldn't the address be dependent on the address
family of &temp, rather than the socket ?

Sorry if the format of my mail is not good, it is my first post here...
I am also not subscribed to this list, so please CC me in any answer.

Best regards,
Sebastien.

-- 
Sebastien Decugis
Research fellow
Network Architecture Group
NICT (nict.go.jp)