diff options
author | Jakub Kicinski <kuba@kernel.org> | 2022-10-13 03:50:40 +0300 |
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committer | Jakub Kicinski <kuba@kernel.org> | 2022-10-13 03:50:40 +0300 |
commit | 4f0f2121a63ca57845fac78beb313ae6d2b8e957 (patch) | |
tree | 4950aa7712d9acefbff34efec23105915293f8c8 | |
parent | 3a732b46736cd8a29092e4b0b1a9ba83e672bf89 (diff) | |
parent | f49cd2f4d6170d27a2c61f1fecb03d8a70c91f57 (diff) | |
download | linux-4f0f2121a63ca57845fac78beb313ae6d2b8e957.tar.xz |
Merge branch 'tcp-udp-fix-memory-leaks-and-data-races-around-ipv6_addrform'
Kuniyuki Iwashima says:
====================
tcp/udp: Fix memory leaks and data races around IPV6_ADDRFORM.
This series fixes some memory leaks and data races caused in the
same scenario where one thread converts an IPv6 socket into IPv4
with IPV6_ADDRFORM and another accesses the socket concurrently.
v4: https://lore.kernel.org/netdev/20221004171802.40968-1-kuniyu@amazon.com/
v3 (Resend): https://lore.kernel.org/netdev/20221003154425.49458-1-kuniyu@amazon.com/
v3: https://lore.kernel.org/netdev/20220929012542.55424-1-kuniyu@amazon.com/
v2: https://lore.kernel.org/netdev/20220928002741.64237-1-kuniyu@amazon.com/
v1: https://lore.kernel.org/netdev/20220927161209.32939-1-kuniyu@amazon.com/
====================
Link: https://lore.kernel.org/r/20221006185349.74777-1-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
-rw-r--r-- | include/net/ipv6.h | 2 | ||||
-rw-r--r-- | include/net/udp.h | 2 | ||||
-rw-r--r-- | include/net/udplite.h | 8 | ||||
-rw-r--r-- | net/core/sock.c | 6 | ||||
-rw-r--r-- | net/ipv4/af_inet.c | 23 | ||||
-rw-r--r-- | net/ipv4/tcp.c | 10 | ||||
-rw-r--r-- | net/ipv4/udp.c | 9 | ||||
-rw-r--r-- | net/ipv4/udplite.c | 8 | ||||
-rw-r--r-- | net/ipv6/af_inet6.c | 14 | ||||
-rw-r--r-- | net/ipv6/ipv6_sockglue.c | 34 | ||||
-rw-r--r-- | net/ipv6/tcp_ipv6.c | 6 | ||||
-rw-r--r-- | net/ipv6/udp.c | 15 | ||||
-rw-r--r-- | net/ipv6/udp_impl.h | 1 | ||||
-rw-r--r-- | net/ipv6/udplite.c | 9 |
14 files changed, 102 insertions, 45 deletions
diff --git a/include/net/ipv6.h b/include/net/ipv6.h index d664ba5812d8..37943ba3a73c 100644 --- a/include/net/ipv6.h +++ b/include/net/ipv6.h @@ -1182,6 +1182,8 @@ void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port, void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info); 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, diff --git a/include/net/udp.h b/include/net/udp.h index 5ee88ddf79c3..fee053bcd17c 100644 --- a/include/net/udp.h +++ b/include/net/udp.h @@ -247,7 +247,7 @@ static inline bool udp_sk_bound_dev_eq(struct net *net, int bound_dev_if, } /* 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); diff --git a/include/net/udplite.h b/include/net/udplite.h index 0143b373602e..299c14ce2bb9 100644 --- a/include/net/udplite.h +++ b/include/net/udplite.h @@ -25,14 +25,6 @@ static __inline__ int udplite_getfrag(void *from, char *to, int offset, 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 */ diff --git a/net/core/sock.c b/net/core/sock.c index eeb6cbac6f49..a3ba0358c77c 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -3610,7 +3610,8 @@ int sock_common_getsockopt(struct socket *sock, int level, int optname, { struct sock *sk = sock->sk; - return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); + /* IPV6_ADDRFORM can change sk->sk_prot under us. */ + return READ_ONCE(sk->sk_prot)->getsockopt(sk, level, optname, optval, optlen); } EXPORT_SYMBOL(sock_common_getsockopt); @@ -3636,7 +3637,8 @@ int sock_common_setsockopt(struct socket *sock, int level, int optname, { struct sock *sk = sock->sk; - return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); + /* IPV6_ADDRFORM can change sk->sk_prot under us. */ + return READ_ONCE(sk->sk_prot)->setsockopt(sk, level, optname, optval, optlen); } EXPORT_SYMBOL(sock_common_setsockopt); diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index e2c219382345..3dd02396517d 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -558,22 +558,27 @@ int inet_dgram_connect(struct socket *sock, struct sockaddr *uaddr, int addr_len, int flags) { struct sock *sk = sock->sk; + const struct proto *prot; int err; if (addr_len < sizeof(uaddr->sa_family)) return -EINVAL; + + /* IPV6_ADDRFORM can change sk->sk_prot under us. */ + prot = READ_ONCE(sk->sk_prot); + if (uaddr->sa_family == AF_UNSPEC) - return sk->sk_prot->disconnect(sk, flags); + return prot->disconnect(sk, flags); if (BPF_CGROUP_PRE_CONNECT_ENABLED(sk)) { - err = sk->sk_prot->pre_connect(sk, uaddr, addr_len); + err = prot->pre_connect(sk, uaddr, addr_len); if (err) return err; } if (data_race(!inet_sk(sk)->inet_num) && inet_autobind(sk)) return -EAGAIN; - return sk->sk_prot->connect(sk, uaddr, addr_len); + return prot->connect(sk, uaddr, addr_len); } EXPORT_SYMBOL(inet_dgram_connect); @@ -734,10 +739,11 @@ EXPORT_SYMBOL(inet_stream_connect); int inet_accept(struct socket *sock, struct socket *newsock, int flags, bool kern) { - struct sock *sk1 = sock->sk; + struct sock *sk1 = sock->sk, *sk2; int err = -EINVAL; - struct sock *sk2 = sk1->sk_prot->accept(sk1, flags, &err, kern); + /* IPV6_ADDRFORM can change sk->sk_prot under us. */ + sk2 = READ_ONCE(sk1->sk_prot)->accept(sk1, flags, &err, kern); if (!sk2) goto do_err; @@ -825,12 +831,15 @@ ssize_t inet_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags) { struct sock *sk = sock->sk; + const struct proto *prot; if (unlikely(inet_send_prepare(sk))) return -EAGAIN; - if (sk->sk_prot->sendpage) - return sk->sk_prot->sendpage(sk, page, offset, size, flags); + /* IPV6_ADDRFORM can change sk->sk_prot under us. */ + prot = READ_ONCE(sk->sk_prot); + if (prot->sendpage) + return prot->sendpage(sk, page, offset, size, flags); return sock_no_sendpage(sock, page, offset, size, flags); } EXPORT_SYMBOL(inet_sendpage); diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 0c51abeee172..f8232811a5be 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -3796,8 +3796,9 @@ int tcp_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval, const struct inet_connection_sock *icsk = inet_csk(sk); if (level != SOL_TCP) - return icsk->icsk_af_ops->setsockopt(sk, level, optname, - optval, optlen); + /* Paired with WRITE_ONCE() in do_ipv6_setsockopt() and tcp_v6_connect() */ + return READ_ONCE(icsk->icsk_af_ops)->setsockopt(sk, level, optname, + optval, optlen); return do_tcp_setsockopt(sk, level, optname, optval, optlen); } EXPORT_SYMBOL(tcp_setsockopt); @@ -4396,8 +4397,9 @@ int tcp_getsockopt(struct sock *sk, int level, int optname, char __user *optval, struct inet_connection_sock *icsk = inet_csk(sk); if (level != SOL_TCP) - return icsk->icsk_af_ops->getsockopt(sk, level, optname, - optval, optlen); + /* Paired with WRITE_ONCE() in do_ipv6_setsockopt() and tcp_v6_connect() */ + return READ_ONCE(icsk->icsk_af_ops)->getsockopt(sk, level, optname, + optval, optlen); return do_tcp_getsockopt(sk, level, optname, USER_SOCKPTR(optval), USER_SOCKPTR(optlen)); } diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index d63118ce5900..8126f67d18b3 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -1598,7 +1598,7 @@ 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); @@ -1611,10 +1611,14 @@ 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) { @@ -1622,7 +1626,6 @@ 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) { diff --git a/net/ipv4/udplite.c b/net/ipv4/udplite.c index 6e08a76ae1e7..e0c9cc39b81e 100644 --- a/net/ipv4/udplite.c +++ b/net/ipv4/udplite.c @@ -17,6 +17,14 @@ 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); diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c index d40b7d60e00e..024191004982 100644 --- a/net/ipv6/af_inet6.c +++ b/net/ipv6/af_inet6.c @@ -109,6 +109,12 @@ static __inline__ struct ipv6_pinfo *inet6_sk_generic(struct sock *sk) 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) { @@ -201,7 +207,7 @@ 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; @@ -510,6 +516,12 @@ void inet6_destroy_sock(struct sock *sk) } EXPORT_SYMBOL_GPL(inet6_destroy_sock); +void inet6_cleanup_sock(struct sock *sk) +{ + inet6_destroy_sock(sk); +} +EXPORT_SYMBOL_GPL(inet6_cleanup_sock); + /* * This does both peername and sockname. */ diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c index 2d2f4dd9e5df..532f4478c884 100644 --- a/net/ipv6/ipv6_sockglue.c +++ b/net/ipv6/ipv6_sockglue.c @@ -419,15 +419,18 @@ int do_ipv6_setsockopt(struct sock *sk, int level, int optname, rtnl_lock(); sockopt_lock_sock(sk); + /* Another thread has converted the socket into IPv4 with + * IPV6_ADDRFORM concurrently. + */ + if (unlikely(sk->sk_family != AF_INET6)) + goto unlock; + switch (optname) { case IPV6_ADDRFORM: if (optlen < sizeof(int)) goto e_inval; if (val == PF_INET) { - struct ipv6_txoptions *opt; - struct sk_buff *pktopt; - if (sk->sk_type == SOCK_RAW) break; @@ -458,7 +461,6 @@ int do_ipv6_setsockopt(struct sock *sk, int level, int optname, break; } - fl6_free_socklist(sk); __ipv6_sock_mc_close(sk); __ipv6_sock_ac_close(sk); @@ -475,9 +477,10 @@ int do_ipv6_setsockopt(struct sock *sk, int level, int optname, sock_prot_inuse_add(net, sk->sk_prot, -1); sock_prot_inuse_add(net, &tcp_prot, 1); - /* Paired with READ_ONCE(sk->sk_prot) in net/ipv6/af_inet6.c */ + /* Paired with READ_ONCE(sk->sk_prot) in inet6_stream_ops */ WRITE_ONCE(sk->sk_prot, &tcp_prot); - icsk->icsk_af_ops = &ipv4_specific; + /* Paired with READ_ONCE() in tcp_(get|set)sockopt() */ + WRITE_ONCE(icsk->icsk_af_ops, &ipv4_specific); sk->sk_socket->ops = &inet_stream_ops; sk->sk_family = PF_INET; tcp_sync_mss(sk, icsk->icsk_pmtu_cookie); @@ -490,19 +493,19 @@ int do_ipv6_setsockopt(struct sock *sk, int level, int optname, sock_prot_inuse_add(net, sk->sk_prot, -1); sock_prot_inuse_add(net, prot, 1); - /* Paired with READ_ONCE(sk->sk_prot) in net/ipv6/af_inet6.c */ + /* Paired with READ_ONCE(sk->sk_prot) in inet6_dgram_ops */ WRITE_ONCE(sk->sk_prot, prot); sk->sk_socket->ops = &inet_dgram_ops; sk->sk_family = PF_INET; } - opt = xchg((__force struct ipv6_txoptions **)&np->opt, - NULL); - if (opt) { - atomic_sub(opt->tot_len, &sk->sk_omem_alloc); - txopt_put(opt); - } - pktopt = xchg(&np->pktoptions, NULL); - kfree_skb(pktopt); + + /* Disable all options not to allocate memory anymore, + * but there is still a race. See the lockless path + * in udpv6_sendmsg() and ipv6_local_rxpmtu(). + */ + np->rxopt.all = 0; + + inet6_cleanup_sock(sk); /* * ... and add it to the refcnt debug socks count @@ -994,6 +997,7 @@ done: break; } +unlock: sockopt_release_sock(sk); if (needs_rtnl) rtnl_unlock(); diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index a8adda623da1..2a3f9296df1e 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -238,7 +238,8 @@ static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr, sin.sin_port = usin->sin6_port; sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3]; - icsk->icsk_af_ops = &ipv6_mapped; + /* Paired with READ_ONCE() in tcp_(get|set)sockopt() */ + WRITE_ONCE(icsk->icsk_af_ops, &ipv6_mapped); if (sk_is_mptcp(sk)) mptcpv6_handle_mapped(sk, true); sk->sk_backlog_rcv = tcp_v4_do_rcv; @@ -250,7 +251,8 @@ static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr, if (err) { icsk->icsk_ext_hdr_len = exthdrlen; - icsk->icsk_af_ops = &ipv6_specific; + /* Paired with READ_ONCE() in tcp_(get|set)sockopt() */ + WRITE_ONCE(icsk->icsk_af_ops, &ipv6_specific); if (sk_is_mptcp(sk)) mptcpv6_handle_mapped(sk, false); sk->sk_backlog_rcv = tcp_v6_do_rcv; diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index 91e795bb9ade..8d09f0ea5b8c 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -56,6 +56,19 @@ #include <trace/events/skb.h> #include "udp_impl.h" +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, @@ -1733,7 +1746,7 @@ 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, diff --git a/net/ipv6/udp_impl.h b/net/ipv6/udp_impl.h index 4251e49d32a0..0590f566379d 100644 --- a/net/ipv6/udp_impl.h +++ b/net/ipv6/udp_impl.h @@ -12,6 +12,7 @@ int __udp6_lib_rcv(struct sk_buff *, struct udp_table *, int); int __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); void udp_v6_rehash(struct sock *sk); diff --git a/net/ipv6/udplite.c b/net/ipv6/udplite.c index b70725856259..67eaf3ca14ce 100644 --- a/net/ipv6/udplite.c +++ b/net/ipv6/udplite.c @@ -12,6 +12,13 @@ #include <linux/proc_fs.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); @@ -38,7 +45,7 @@ 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, |