From: Joanne Koong <joannelkoong@xxxxxxxxx>
Commit d5a42de8bdbe ("net: Add a second bind table hashed by port and
address") added a second bind table, bhash2, that hashes by a socket's port
and rcv address.
However, there are two cases where the socket's rcv saddr can change
after it has been binded:
1) The case where there is a bind() call on "::" (IPADDR_ANY) and then
a connect() call. The kernel will assign the socket an address when it
handles the connect()
2) In inet_sk_reselect_saddr(), which is called when rerouting fails
when rebuilding the sk header (invoked by inet_sk_rebuild_header)
In these two cases, we need to update the bhash2 table by removing the
entry for the old address, and adding a new entry reflecting the updated
address.
Reported-by: syzbot+015d756bbd1f8b5c8f09@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: d5a42de8bdbe ("net: Add a second bind table hashed by port and address")
Signed-off-by: Joanne Koong <joannelkoong@xxxxxxxxx>
Reviewed-by: Eric Dumazet <edumzet@xxxxxxxxxx>
---
include/net/inet_hashtables.h | 6 ++-
include/net/ipv6.h | 2 +-
net/dccp/ipv4.c | 10 +++--
net/dccp/ipv6.c | 4 +-
net/ipv4/af_inet.c | 7 +++-
net/ipv4/inet_hashtables.c | 69 ++++++++++++++++++++++++++++++++---
net/ipv4/tcp_ipv4.c | 8 +++-
net/ipv6/inet6_hashtables.c | 4 +-
net/ipv6/tcp_ipv6.c | 4 +-
9 files changed, 96 insertions(+), 18 deletions(-)
diff --git a/include/net/inet_hashtables.h b/include/net/inet_hashtables.h
index a0887b70967b..2c331ce6ca73 100644
--- a/include/net/inet_hashtables.h
+++ b/include/net/inet_hashtables.h
@@ -448,11 +448,13 @@ static inline void sk_rcv_saddr_set(struct sock *sk, __be32 addr)
}
int __inet_hash_connect(struct inet_timewait_death_row *death_row,
- struct sock *sk, u64 port_offset,
+ struct sock *sk, u64 port_offset, bool prev_inaddr_any,
int (*check_established)(struct inet_timewait_death_row *,
struct sock *, __u16,
struct inet_timewait_sock **));
int inet_hash_connect(struct inet_timewait_death_row *death_row,
- struct sock *sk);
+ struct sock *sk, bool prev_inaddr_any);
+
+int inet_bhash2_update_saddr(struct sock *sk);
#endif /* _INET_HASHTABLES_H */
diff --git a/include/net/ipv6.h b/include/net/ipv6.h
index 5b38bf1a586b..6a50aca56d50 100644
--- a/include/net/ipv6.h
+++ b/include/net/ipv6.h
@@ -1187,7 +1187,7 @@ int inet6_compat_ioctl(struct socket *sock, unsigned int cmd,
unsigned long arg);
int inet6_hash_connect(struct inet_timewait_death_row *death_row,
- struct sock *sk);
+ struct sock *sk, bool prev_inaddr_any);
int inet6_sendmsg(struct socket *sock, struct msghdr *msg, size_t size);
int inet6_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
int flags);
diff --git a/net/dccp/ipv4.c b/net/dccp/ipv4.c
index da6e3b20cd75..37a8bc3ee49e 100644
--- a/net/dccp/ipv4.c
+++ b/net/dccp/ipv4.c
@@ -47,12 +47,13 @@ int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
const struct sockaddr_in *usin = (struct sockaddr_in *)uaddr;
struct inet_sock *inet = inet_sk(sk);
struct dccp_sock *dp = dccp_sk(sk);
+ struct ip_options_rcu *inet_opt;
__be16 orig_sport, orig_dport;
+ bool prev_inaddr_any = false;
__be32 daddr, nexthop;
struct flowi4 *fl4;
struct rtable *rt;
int err;
- struct ip_options_rcu *inet_opt;
dp->dccps_role = DCCP_ROLE_CLIENT;
@@ -89,8 +90,11 @@ int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
if (inet_opt == NULL || !inet_opt->opt.srr)
daddr = fl4->daddr;
- if (inet->inet_saddr == 0)
+ if (inet->inet_saddr == 0) {
inet->inet_saddr = fl4->saddr;
+ prev_inaddr_any = true;
+ }
+
sk_rcv_saddr_set(sk, inet->inet_saddr);
inet->inet_dport = usin->sin_port;
sk_daddr_set(sk, daddr);
@@ -105,7 +109,7 @@ int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
* complete initialization after this.
*/
dccp_set_state(sk, DCCP_REQUESTING);
- err = inet_hash_connect(&dccp_death_row, sk);
+ err = inet_hash_connect(&dccp_death_row, sk, prev_inaddr_any);
if (err != 0)
goto failure;
diff --git a/net/dccp/ipv6.c b/net/dccp/ipv6.c
index fd44638ec16b..03013522acab 100644
--- a/net/dccp/ipv6.c
+++ b/net/dccp/ipv6.c
@@ -824,6 +824,7 @@ static int dccp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
struct ipv6_pinfo *np = inet6_sk(sk);
struct dccp_sock *dp = dccp_sk(sk);
struct in6_addr *saddr = NULL, *final_p, final;
+ bool prev_inaddr_any = false;
struct ipv6_txoptions *opt;
struct flowi6 fl6;
struct dst_entry *dst;
@@ -936,6 +937,7 @@ static int dccp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
if (saddr == NULL) {
saddr = &fl6.saddr;
sk->sk_v6_rcv_saddr = *saddr;
+ prev_inaddr_any = true;
}
/* set the source address */
@@ -951,7 +953,7 @@ static int dccp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
inet->inet_dport = usin->sin6_port;
dccp_set_state(sk, DCCP_REQUESTING);
- err = inet6_hash_connect(&dccp_death_row, sk);
+ err = inet6_hash_connect(&dccp_death_row, sk, prev_inaddr_any);
if (err)
goto late_failure;
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index 93da9f783bec..ad627a99ff9d 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -1221,10 +1221,11 @@ static int inet_sk_reselect_saddr(struct sock *sk)
struct inet_sock *inet = inet_sk(sk);
__be32 old_saddr = inet->inet_saddr;
__be32 daddr = inet->inet_daddr;
+ struct ip_options_rcu *inet_opt;
struct flowi4 *fl4;
struct rtable *rt;
__be32 new_saddr;
- struct ip_options_rcu *inet_opt;
+ int err;
inet_opt = rcu_dereference_protected(inet->inet_opt,
lockdep_sock_is_held(sk));
@@ -1253,6 +1254,10 @@ static int inet_sk_reselect_saddr(struct sock *sk)
inet->inet_saddr = inet->inet_rcv_saddr = new_saddr;
+ err = inet_bhash2_update_saddr(sk);
+ if (err)
+ return err;
+
/*
* XXX The only one ugly spot where we need to
* XXX really change the sockets identity after
diff --git a/net/ipv4/inet_hashtables.c b/net/ipv4/inet_hashtables.c
index e8de5e699b3f..0b43a30b6363 100644
--- a/net/ipv4/inet_hashtables.c
+++ b/net/ipv4/inet_hashtables.c
@@ -826,6 +826,54 @@ inet_bind2_bucket_find(struct inet_hashinfo *hinfo, struct net *net,
return bhash2;
}
+/* the lock for the socket's corresponding bhash entry must be held */
+int __inet_bhash2_update_saddr(struct sock *sk, struct inet_hashinfo *hinfo,
+ struct net *net, int port, int l3mdev)
+{
+ struct inet_bind2_hashbucket *head2;
+ struct inet_bind2_bucket *tb2;
+
+ tb2 = inet_bind2_bucket_find(hinfo, net, port, l3mdev, sk,
+ &head2);
+ if (!tb2) {
+ tb2 = inet_bind2_bucket_create(hinfo->bind2_bucket_cachep,
+ net, head2, port, l3mdev, sk);
+ if (!tb2)
+ return -ENOMEM;
+ }
+
+ /* Remove the socket's old entry from bhash2 */
+ __sk_del_bind2_node(sk);
+
+ sk_add_bind2_node(sk, &tb2->owners);
+ inet_csk(sk)->icsk_bind2_hash = tb2;
+
+ return 0;
+}
+
+/* This should be called if/when a socket's rcv saddr changes after it has
+ * been binded.
+ */
+int inet_bhash2_update_saddr(struct sock *sk)
+{
+ struct inet_hashinfo *hinfo = sk->sk_prot->h.hashinfo;
+ int l3mdev = inet_sk_bound_l3mdev(sk);
+ struct inet_bind_hashbucket *head;
+ int port = inet_sk(sk)->inet_num;
+ struct net *net = sock_net(sk);
+ int err;
+
+ head = &hinfo->bhash[inet_bhashfn(net, port, hinfo->bhash_size)];
+
+ spin_lock_bh(&head->lock);
+
+ err = __inet_bhash2_update_saddr(sk, hinfo, net, port, l3mdev);
+
+ spin_unlock_bh(&head->lock);
+
+ return err;
+}
+
/* RFC 6056 3.3.4. Algorithm 4: Double-Hash Port Selection Algorithm
* Note that we use 32bit integers (vs RFC 'short integers')
* because 2^16 is not a multiple of num_ephemeral and this
@@ -840,7 +888,7 @@ inet_bind2_bucket_find(struct inet_hashinfo *hinfo, struct net *net,
static u32 *table_perturb;
int __inet_hash_connect(struct inet_timewait_death_row *death_row,
- struct sock *sk, u64 port_offset,
+ struct sock *sk, u64 port_offset, bool prev_inaddr_any,
int (*check_established)(struct inet_timewait_death_row *,
struct sock *, __u16, struct inet_timewait_sock **))
{
@@ -858,11 +906,24 @@ int __inet_hash_connect(struct inet_timewait_death_row *death_row,
int l3mdev;
u32 index;
+ l3mdev = inet_sk_bound_l3mdev(sk);
+
if (port) {
head = &hinfo->bhash[inet_bhashfn(net, port,
hinfo->bhash_size)];
tb = inet_csk(sk)->icsk_bind_hash;
+
spin_lock_bh(&head->lock);
+
+ if (prev_inaddr_any) {
+ ret = __inet_bhash2_update_saddr(sk, hinfo, net, port,
+ l3mdev);
+ if (ret) {
+ spin_unlock_bh(&head->lock);
+ return ret;
+ }
+ }
+
if (sk_head(&tb->owners) == sk && !sk->sk_bind_node.next) {
inet_ehash_nolisten(sk, NULL, NULL);
spin_unlock_bh(&head->lock);
@@ -875,8 +936,6 @@ int __inet_hash_connect(struct inet_timewait_death_row *death_row,
return ret;
}
- l3mdev = inet_sk_bound_l3mdev(sk);
-
inet_get_local_port_range(net, &low, &high);
high++; /* [32768, 60999] -> [32768, 61000[ */
remaining = high - low;
@@ -987,13 +1046,13 @@ int __inet_hash_connect(struct inet_timewait_death_row *death_row,
* Bind a port for a connect operation and hash it.
*/
int inet_hash_connect(struct inet_timewait_death_row *death_row,
- struct sock *sk)
+ struct sock *sk, bool prev_inaddr_any)
{
u64 port_offset = 0;
if (!inet_sk(sk)->inet_num)
port_offset = inet_sk_port_offset(sk);
- return __inet_hash_connect(death_row, sk, port_offset,
+ return __inet_hash_connect(death_row, sk, port_offset, prev_inaddr_any,
__inet_check_established);
}
EXPORT_SYMBOL_GPL(inet_hash_connect);
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index dac2650f3863..adf8d750933d 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -203,6 +203,7 @@ int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
struct inet_sock *inet = inet_sk(sk);
struct tcp_sock *tp = tcp_sk(sk);
__be16 orig_sport, orig_dport;
+ bool prev_inaddr_any = false;
__be32 daddr, nexthop;
struct flowi4 *fl4;
struct rtable *rt;
@@ -246,8 +247,11 @@ int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
if (!inet_opt || !inet_opt->opt.srr)
daddr = fl4->daddr;
- if (!inet->inet_saddr)
+ if (!inet->inet_saddr) {
inet->inet_saddr = fl4->saddr;
+ prev_inaddr_any = true;
+ }
+
sk_rcv_saddr_set(sk, inet->inet_saddr);
if (tp->rx_opt.ts_recent_stamp && inet->inet_daddr != daddr) {
@@ -273,7 +277,7 @@ int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
* complete initialization after this.
*/
tcp_set_state(sk, TCP_SYN_SENT);
- err = inet_hash_connect(tcp_death_row, sk);
+ err = inet_hash_connect(tcp_death_row, sk, prev_inaddr_any);
if (err)
goto failure;
diff --git a/net/ipv6/inet6_hashtables.c b/net/ipv6/inet6_hashtables.c
index 7d53d62783b1..c87c5933f3be 100644
--- a/net/ipv6/inet6_hashtables.c
+++ b/net/ipv6/inet6_hashtables.c
@@ -317,13 +317,13 @@ static u64 inet6_sk_port_offset(const struct sock *sk)
}
int inet6_hash_connect(struct inet_timewait_death_row *death_row,
- struct sock *sk)
+ struct sock *sk, bool prev_inaddr_any)
{
u64 port_offset = 0;
if (!inet_sk(sk)->inet_num)
port_offset = inet6_sk_port_offset(sk);
- return __inet_hash_connect(death_row, sk, port_offset,
+ return __inet_hash_connect(death_row, sk, port_offset, prev_inaddr_any,
__inet6_check_established);
}
EXPORT_SYMBOL_GPL(inet6_hash_connect);
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index f37dd4aa91c6..81e3312c2a97 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -152,6 +152,7 @@ static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
struct ipv6_pinfo *np = tcp_inet6_sk(sk);
struct tcp_sock *tp = tcp_sk(sk);
struct in6_addr *saddr = NULL, *final_p, final;
+ bool prev_inaddr_any = false;
struct ipv6_txoptions *opt;
struct flowi6 fl6;
struct dst_entry *dst;
@@ -289,6 +290,7 @@ static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
if (!saddr) {
saddr = &fl6.saddr;
sk->sk_v6_rcv_saddr = *saddr;
+ prev_inaddr_any = true;
}
/* set the source address */
@@ -309,7 +311,7 @@ static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
tcp_set_state(sk, TCP_SYN_SENT);
tcp_death_row = sock_net(sk)->ipv4.tcp_death_row;
- err = inet6_hash_connect(tcp_death_row, sk);
+ err = inet6_hash_connect(tcp_death_row, sk, prev_inaddr_any);
if (err)
goto late_failure;
--
2.30.2
