From: Xin Long <lucien....@gmail.com>
Date: Tue, 7 Feb 2017 20:56:08 +0800
> Commit 6f29a1306131 ("sctp: sctp_addr_id2transport should verify the
> addr before looking up assoc") invoked sctp_verify_addr to verify the
> addr.
>
> But it didn't check af variable beforehand, once users pass an address
> with family = 0 through sockopt, sctp_get_af_specific will return NULL
> and NULL pointer dereference will be caused by af->sockaddr_len.
>
> This patch is to fix it by returning NULL if af variable is NULL.
>
> Fixes: 6f29a1306131 ("sctp: sctp_addr_id2transport should verify the addr
> before looking up assoc")
> Signed-off-by: Xin Long <lucien....@gmail.com>
Applied, thank you.
