dccp: Call inet6_destroy_sock() via sk->sk_destruct().

stable inclusion
from stable-v4.19.282
commit b165119e6cc96ceaeea061ecca0750f0052aa2c8
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I7BZ5U


CVE: NA

--------------------------------

commit 1651951e upstream.

After commit d38afeec ("tcp/udp: Call inet6_destroy_sock()
in IPv6 sk->sk_destruct()."), we call inet6_destroy_sock() in
sk->sk_destruct() by setting inet6_sock_destruct() to it to make
sure we do not leak inet6-specific resources.

DCCP sets its own sk->sk_destruct() in the dccp_init_sock(), and
DCCPv6 socket shares it by calling the same init function via
dccp_v6_init_sock().

To call inet6_sock_destruct() from DCCPv6 sk->sk_destruct(), we
export it and set dccp_v6_sk_destruct() in the init function.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Yongqiang Liu <liuyongqiang13@huawei.com>