--- /dev/null
+From d38afeec26ed4739c640bf286c270559aab2ba5f Mon Sep 17 00:00:00 2001
+From: Kuniyuki Iwashima <kuniyu@amazon.com>
+Date: Thu, 6 Oct 2022 11:53:47 -0700
+Subject: tcp/udp: Call inet6_destroy_sock() in IPv6 sk->sk_destruct().
+
+From: Kuniyuki Iwashima <kuniyu@amazon.com>
+
+commit d38afeec26ed4739c640bf286c270559aab2ba5f upstream.
+
+Originally, inet6_sk(sk)->XXX were changed under lock_sock(), so we were
+able to clean them up by calling inet6_destroy_sock() during the IPv6 ->
+IPv4 conversion by IPV6_ADDRFORM. However, commit 03485f2adcde ("udpv6:
+Add lockless sendmsg() support") added a lockless memory allocation path,
+which could cause a memory leak:
+
+setsockopt(IPV6_ADDRFORM) sendmsg()
++-----------------------+ +-------+
+- do_ipv6_setsockopt(sk, ...) - udpv6_sendmsg(sk, ...)
+ - sockopt_lock_sock(sk) ^._ called via udpv6_prot
+ - lock_sock(sk) before WRITE_ONCE()
+ - WRITE_ONCE(sk->sk_prot, &tcp_prot)
+ - inet6_destroy_sock() - if (!corkreq)
+ - sockopt_release_sock(sk) - ip6_make_skb(sk, ...)
+ - release_sock(sk) ^._ lockless fast path for
+ the non-corking case
+
+ - __ip6_append_data(sk, ...)
+ - ipv6_local_rxpmtu(sk, ...)
+ - xchg(&np->rxpmtu, skb)
+ ^._ rxpmtu is never freed.
+
+ - goto out_no_dst;
+
+ - lock_sock(sk)
+
+For now, rxpmtu is only the case, but not to miss the future change
+and a similar bug fixed in commit e27326009a3d ("net: ping6: Fix
+memleak in ipv6_renew_options()."), let's set a new function to IPv6
+sk->sk_destruct() and call inet6_cleanup_sock() there. Since the
+conversion does not change sk->sk_destruct(), we can guarantee that
+we can clean up IPv6 resources finally.
+
+We can now remove all inet6_destroy_sock() calls from IPv6 protocol
+specific ->destroy() functions, but such changes are invasive to
+backport. So they can be posted as a follow-up later for net-next.
+
+Fixes: 03485f2adcde ("udpv6: Add lockless sendmsg() support")
+Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
+Signed-off-by: Jakub Kicinski <kuba@kernel.org>
+Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ include/net/ipv6.h | 1 +
+ include/net/udp.h | 2 +-
+ include/net/udplite.h | 8 --------
+ net/ipv4/udp.c | 9 ++++++---
+ net/ipv4/udplite.c | 8 ++++++++
+ net/ipv6/af_inet6.c | 8 +++++++-
+ net/ipv6/udp.c | 15 ++++++++++++++-
+ net/ipv6/udp_impl.h | 1 +
+ net/ipv6/udplite.c | 9 ++++++++-
+ 9 files changed, 46 insertions(+), 15 deletions(-)
+
+--- a/include/net/ipv6.h
++++ b/include/net/ipv6.h
+@@ -943,6 +943,7 @@ void ipv6_local_error(struct sock *sk, i
+ void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu);
+
+ void inet6_cleanup_sock(struct sock *sk);
++void inet6_sock_destruct(struct sock *sk);
+ int inet6_release(struct socket *sock);
+ int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len);
+ int inet6_getname(struct socket *sock, struct sockaddr *uaddr, int *uaddr_len,
+--- a/include/net/udp.h
++++ b/include/net/udp.h
+@@ -251,7 +251,7 @@ static inline int udp_rqueue_get(struct
+ }
+
+ /* net/ipv4/udp.c */
+-void udp_destruct_sock(struct sock *sk);
++void udp_destruct_common(struct sock *sk);
+ void skb_consume_udp(struct sock *sk, struct sk_buff *skb, int len);
+ int __udp_enqueue_schedule_skb(struct sock *sk, struct sk_buff *skb);
+ void udp_skb_destructor(struct sock *sk, struct sk_buff *skb);
+--- a/include/net/udplite.h
++++ b/include/net/udplite.h
+@@ -24,14 +24,6 @@ static __inline__ int udplite_getfrag(vo
+ return copy_from_iter_full(to, len, &msg->msg_iter) ? 0 : -EFAULT;
+ }
+
+-/* Designate sk as UDP-Lite socket */
+-static inline int udplite_sk_init(struct sock *sk)
+-{
+- udp_init_sock(sk);
+- udp_sk(sk)->pcflag = UDPLITE_BIT;
+- return 0;
+-}
+-
+ /*
+ * Checksumming routines
+ */
+--- a/net/ipv4/udp.c
++++ b/net/ipv4/udp.c
+@@ -1380,7 +1380,7 @@ drop:
+ }
+ EXPORT_SYMBOL_GPL(__udp_enqueue_schedule_skb);
+
+-void udp_destruct_sock(struct sock *sk)
++void udp_destruct_common(struct sock *sk)
+ {
+ /* reclaim completely the forward allocated memory */
+ struct udp_sock *up = udp_sk(sk);
+@@ -1393,10 +1393,14 @@ void udp_destruct_sock(struct sock *sk)
+ kfree_skb(skb);
+ }
+ udp_rmem_release(sk, total, 0, true);
++}
++EXPORT_SYMBOL_GPL(udp_destruct_common);
+
++static void udp_destruct_sock(struct sock *sk)
++{
++ udp_destruct_common(sk);
+ inet_sock_destruct(sk);
+ }
+-EXPORT_SYMBOL_GPL(udp_destruct_sock);
+
+ int udp_init_sock(struct sock *sk)
+ {
+@@ -1404,7 +1408,6 @@ int udp_init_sock(struct sock *sk)
+ sk->sk_destruct = udp_destruct_sock;
+ return 0;
+ }
+-EXPORT_SYMBOL_GPL(udp_init_sock);
+
+ void skb_consume_udp(struct sock *sk, struct sk_buff *skb, int len)
+ {
+--- a/net/ipv4/udplite.c
++++ b/net/ipv4/udplite.c
+@@ -19,6 +19,14 @@
+ struct udp_table udplite_table __read_mostly;
+ EXPORT_SYMBOL(udplite_table);
+
++/* Designate sk as UDP-Lite socket */
++static int udplite_sk_init(struct sock *sk)
++{
++ udp_init_sock(sk);
++ udp_sk(sk)->pcflag = UDPLITE_BIT;
++ return 0;
++}
++
+ static int udplite_rcv(struct sk_buff *skb)
+ {
+ return __udp4_lib_rcv(skb, &udplite_table, IPPROTO_UDPLITE);
+--- a/net/ipv6/af_inet6.c
++++ b/net/ipv6/af_inet6.c
+@@ -107,6 +107,12 @@ static __inline__ struct ipv6_pinfo *ine
+ return (struct ipv6_pinfo *)(((u8 *)sk) + offset);
+ }
+
++void inet6_sock_destruct(struct sock *sk)
++{
++ inet6_cleanup_sock(sk);
++ inet_sock_destruct(sk);
++}
++
+ static int inet6_create(struct net *net, struct socket *sock, int protocol,
+ int kern)
+ {
+@@ -199,7 +205,7 @@ lookup_protocol:
+ inet->hdrincl = 1;
+ }
+
+- sk->sk_destruct = inet_sock_destruct;
++ sk->sk_destruct = inet6_sock_destruct;
+ sk->sk_family = PF_INET6;
+ sk->sk_protocol = protocol;
+
+--- a/net/ipv6/udp.c
++++ b/net/ipv6/udp.c
+@@ -66,6 +66,19 @@ static bool udp6_lib_exact_dif_match(str
+ return false;
+ }
+
++static void udpv6_destruct_sock(struct sock *sk)
++{
++ udp_destruct_common(sk);
++ inet6_sock_destruct(sk);
++}
++
++int udpv6_init_sock(struct sock *sk)
++{
++ skb_queue_head_init(&udp_sk(sk)->reader_queue);
++ sk->sk_destruct = udpv6_destruct_sock;
++ return 0;
++}
++
+ static u32 udp6_ehashfn(const struct net *net,
+ const struct in6_addr *laddr,
+ const u16 lport,
+@@ -1552,7 +1565,7 @@ struct proto udpv6_prot = {
+ .connect = ip6_datagram_connect,
+ .disconnect = udp_disconnect,
+ .ioctl = udp_ioctl,
+- .init = udp_init_sock,
++ .init = udpv6_init_sock,
+ .destroy = udpv6_destroy_sock,
+ .setsockopt = udpv6_setsockopt,
+ .getsockopt = udpv6_getsockopt,
+--- a/net/ipv6/udp_impl.h
++++ b/net/ipv6/udp_impl.h
+@@ -12,6 +12,7 @@ int __udp6_lib_rcv(struct sk_buff *, str
+ void __udp6_lib_err(struct sk_buff *, struct inet6_skb_parm *, u8, u8, int,
+ __be32, struct udp_table *);
+
++int udpv6_init_sock(struct sock *sk);
+ int udp_v6_get_port(struct sock *sk, unsigned short snum);
+
+ int udpv6_getsockopt(struct sock *sk, int level, int optname,
+--- a/net/ipv6/udplite.c
++++ b/net/ipv6/udplite.c
+@@ -14,6 +14,13 @@
+ #include <linux/export.h>
+ #include "udp_impl.h"
+
++static int udplitev6_sk_init(struct sock *sk)
++{
++ udpv6_init_sock(sk);
++ udp_sk(sk)->pcflag = UDPLITE_BIT;
++ return 0;
++}
++
+ static int udplitev6_rcv(struct sk_buff *skb)
+ {
+ return __udp6_lib_rcv(skb, &udplite_table, IPPROTO_UDPLITE);
+@@ -39,7 +46,7 @@ struct proto udplitev6_prot = {
+ .connect = ip6_datagram_connect,
+ .disconnect = udp_disconnect,
+ .ioctl = udp_ioctl,
+- .init = udplite_sk_init,
++ .init = udplitev6_sk_init,
+ .destroy = udpv6_destroy_sock,
+ .setsockopt = udpv6_setsockopt,
+ .getsockopt = udpv6_getsockopt,