5.4 LTS has backported commit ca43ccf41224 ("dccp/tcp: Avoid negative sk_forward_alloc by ipv6_pinfo.pktoptions.") and commit 62ec33b44e0f ("net: Remove WARN_ON_ONCE(sk->sk_forward_alloc) from sk_stream_kill_queues()."), but these are incomplete. There are some patches that have not been backported including key pre-patches commit d38afeec26ed ("tcp/udp: Call inet6_destroy_sock() in IPv6 sk->sk_destruct().") and commit b5fc29233d28 ("inet6: Remove inet6_destroy_sock() in sk->sk_prot->destroy()."). Without them, there are some memory leak bugs.
Backport complete patchset for inet6_destroy_sock() call modification.
Kuniyuki Iwashima (5): udp: Call inet6_destroy_sock() in setsockopt(IPV6_ADDRFORM). tcp/udp: Call inet6_destroy_sock() in IPv6 sk->sk_destruct(). inet6: Remove inet6_destroy_sock() in sk->sk_prot->destroy(). dccp: Call inet6_destroy_sock() via sk->sk_destruct(). sctp: Call inet6_destroy_sock() via sk->sk_destruct().
include/net/ipv6.h | 2 ++ include/net/udp.h | 2 +- include/net/udplite.h | 8 -------- net/dccp/dccp.h | 1 + net/dccp/ipv6.c | 15 ++++++++------- net/dccp/proto.c | 8 +++++++- net/ipv4/udp.c | 9 ++++++--- net/ipv4/udplite.c | 8 ++++++++ net/ipv6/af_inet6.c | 15 ++++++++++++++- net/ipv6/ipv6_sockglue.c | 20 ++++++++------------ net/ipv6/ping.c | 6 ------ net/ipv6/raw.c | 2 -- net/ipv6/tcp_ipv6.c | 8 +------- net/ipv6/udp.c | 17 ++++++++++++++--- net/ipv6/udp_impl.h | 1 + net/ipv6/udplite.c | 9 ++++++++- net/l2tp/l2tp_ip6.c | 2 -- net/sctp/socket.c | 29 +++++++++++++++++++++-------- 18 files changed, 100 insertions(+), 62 deletions(-)