This implements SOCK_DESTROY for UDP sockets similar to what was done
for TCP with commit c1e64e298b8ca ("net: diag: Support destroying TCP
sockets.") A process with a UDP socket targeted for destroy is awakened
and recvmsg fails with ECONNABORTED giving the process notice that
it should close the socket.
Signed-off-by: David Ahern <d...@cumulusnetworks.com>
---
include/net/udp.h | 8 ++++++++
net/ipv4/udp.c | 58 +++++++++++++++++++++++++++++++++++++++++++++++++++++
net/ipv4/udp_diag.c | 55 ++++++++++++++++++++++++++++++++++++++++++++++++++
net/ipv6/udp.c | 45 +++++++++++++++++++++++++++++++++++++++++
4 files changed, 166 insertions(+)
diff --git a/include/net/udp.h b/include/net/udp.h
index 8894d7144189..5c3443634b4d 100644
--- a/include/net/udp.h
+++ b/include/net/udp.h
@@ -251,6 +251,7 @@ int udp_get_port(struct sock *sk, unsigned short snum,
int (*saddr_cmp)(const struct sock *,
const struct sock *));
void udp_err(struct sk_buff *, u32);
+int udp_abort(struct sock *sk, int err);
int udp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len);
int udp_push_pending_frames(struct sock *sk);
void udp_flush_pending_frames(struct sock *sk);
@@ -274,6 +275,9 @@ struct sock *__udp4_lib_lookup(struct net *net, __be32
saddr, __be16 sport,
struct udp_table *tbl, struct sk_buff *skb);
struct sock *udp4_lib_lookup_skb(struct sk_buff *skb,
__be16 sport, __be16 dport);
+struct sock *udp4_lib_lookup_full(struct net *net, __be32 saddr,
+ __be16 sport, __be32 daddr, __be16 dport,
+ int dif, struct udp_table *table);
struct sock *udp6_lib_lookup(struct net *net,
const struct in6_addr *saddr, __be16 sport,
const struct in6_addr *daddr, __be16 dport,
@@ -286,6 +290,10 @@ struct sock *__udp6_lib_lookup(struct net *net,
struct sock *udp6_lib_lookup_skb(struct sk_buff *skb,
__be16 sport, __be16 dport);
+struct sock *udp6_lib_lookup_full(struct net *net,
+ const struct in6_addr *saddr, __be16 sport,
+ const struct in6_addr *daddr, __be16 dport,
+ int dif, struct udp_table *table);
/*
* SNMP statistics for UDP and UDP-Lite
*/
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index e61f7cd65d08..e5b72a7165e1 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -594,6 +594,47 @@ struct sock *udp4_lib_lookup(struct net *net, __be32
saddr, __be16 sport,
EXPORT_SYMBOL_GPL(udp4_lib_lookup);
#endif
+/* caller should hold rcu lock */
+struct sock *udp4_lib_lookup_full(struct net *net, __be32 saddr,
+ __be16 sport, __be32 daddr, __be16 dport,
+ int dif, struct udp_table *table)
+{
+ struct sock *sk;
+ int i;
+
+ for (i = 0; i <= table->mask; i++) {
+ struct udp_hslot *hslot = &table->hash[i];
+
+ sk_for_each_rcu(sk, &hslot->head) {
+ struct inet_sock *inet;
+
+ if (!net_eq(sock_net(sk), net) ||
+ ipv6_only_sock(sk))
+ continue;
+
+ if (dif && sk->sk_bound_dev_if != dif)
+ continue;
+
+ if (sk->sk_family != PF_INET)
+ continue;
+
+ if (udp_sk(sk)->udp_port_hash != ntohs(sport))
+ continue;
+
+ inet = inet_sk(sk);
+ if (inet->inet_rcv_saddr != saddr ||
+ inet->inet_daddr != daddr ||
+ inet->inet_dport != dport)
+ continue;
+
+ return sk;
+ }
+ }
+
+ return NULL;
+}
+EXPORT_SYMBOL(udp4_lib_lookup_full);
+
static inline bool __udp_is_mcast_sock(struct net *net, struct sock *sk,
__be16 loc_port, __be32 loc_addr,
__be16 rmt_port, __be32 rmt_addr,
@@ -2192,6 +2233,22 @@ unsigned int udp_poll(struct file *file, struct socket
*sock, poll_table *wait)
}
EXPORT_SYMBOL(udp_poll);
+int udp_abort(struct sock *sk, int err)
+{
+ lock_sock(sk);
+
+ sk->sk_err = err;
+ sk->sk_error_report(sk);
+ udp_disconnect(sk, 0);
+
+ release_sock(sk);
+
+ sock_put(sk);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(udp_abort);
+
struct proto udp_prot = {
.name = "UDP",
.owner = THIS_MODULE,
@@ -2223,6 +2280,7 @@ struct proto udp_prot = {
.compat_getsockopt = compat_udp_getsockopt,
#endif
.clear_sk = sk_prot_clear_portaddr_nulls,
+ .diag_destroy = udp_abort,
};
EXPORT_SYMBOL(udp_prot);
diff --git a/net/ipv4/udp_diag.c b/net/ipv4/udp_diag.c
index 3d5ccf4b1412..9ed7ae064e08 100644
--- a/net/ipv4/udp_diag.c
+++ b/net/ipv4/udp_diag.c
@@ -165,12 +165,64 @@ static void udp_diag_get_info(struct sock *sk, struct
inet_diag_msg *r,
r->idiag_wqueue = sk_wmem_alloc_get(sk);
}
+#ifdef CONFIG_INET_DIAG_DESTROY
+static int __udp_diag_destroy(struct sk_buff *in_skb,
+ const struct inet_diag_req_v2 *req,
+ struct udp_table *tbl)
+{
+ struct net *net = sock_net(in_skb->sk);
+ struct sock *sk;
+
+ rcu_read_lock();
+
+ if (req->sdiag_family == AF_INET)
+ sk = udp4_lib_lookup_full(net,
+ req->id.idiag_src[0], req->id.idiag_sport,
+ req->id.idiag_dst[0], req->id.idiag_dport,
+ req->id.idiag_if, tbl);
+#if IS_ENABLED(CONFIG_IPV6)
+ else if (req->sdiag_family == AF_INET6)
+ sk = udp6_lib_lookup_full(net,
+ (struct in6_addr *)req->id.idiag_src,
+ req->id.idiag_sport,
+ (struct in6_addr *)req->id.idiag_dst,
+ req->id.idiag_dport,
+ req->id.idiag_if, tbl);
+#endif
+ if (sk && !atomic_inc_not_zero(&sk->sk_refcnt))
+ sk = NULL;
+
+ rcu_read_unlock();
+
+ if (!sk)
+ return -ENOENT;
+
+ return sock_diag_destroy(sk, ECONNABORTED);
+}
+
+static int udp_diag_destroy(struct sk_buff *in_skb,
+ const struct inet_diag_req_v2 *req)
+{
+ return __udp_diag_destroy(in_skb, req, &udp_table);
+}
+
+static int udplite_diag_destroy(struct sk_buff *in_skb,
+ const struct inet_diag_req_v2 *req)
+{
+ return __udp_diag_destroy(in_skb, req, &udplite_table);
+}
+
+#endif
+
static const struct inet_diag_handler udp_diag_handler = {
.dump = udp_diag_dump,
.dump_one = udp_diag_dump_one,
.idiag_get_info = udp_diag_get_info,
.idiag_type = IPPROTO_UDP,
.idiag_info_size = 0,
+#ifdef CONFIG_INET_DIAG_DESTROY
+ .destroy = udp_diag_destroy,
+#endif
};
static void udplite_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
@@ -192,6 +244,9 @@ static const struct inet_diag_handler udplite_diag_handler
= {
.idiag_get_info = udp_diag_get_info,
.idiag_type = IPPROTO_UDPLITE,
.idiag_info_size = 0,
+#ifdef CONFIG_INET_DIAG_DESTROY
+ .destroy = udplite_diag_destroy,
+#endif
};
static int __init udp_diag_init(void)
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 81e2f98b958d..5b697cff88ca 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -317,6 +317,50 @@ struct sock *udp6_lib_lookup(struct net *net, const struct
in6_addr *saddr, __be
EXPORT_SYMBOL_GPL(udp6_lib_lookup);
#endif
+/* caller should hold rcu lock */
+struct sock *udp6_lib_lookup_full(struct net *net,
+ const struct in6_addr *saddr, __be16 sport,
+ const struct in6_addr *daddr, __be16 dport,
+ int dif, struct udp_table *table)
+{
+ struct sock *sk;
+ int i;
+
+ for (i = 0; i <= table->mask; i++) {
+ struct udp_hslot *hslot = &table->hash[i];
+
+ sk_for_each_rcu(sk, &hslot->head) {
+ struct inet_sock *inet;
+
+ if (!net_eq(sock_net(sk), net) ||
+ ipv6_only_sock(sk))
+ continue;
+
+ if (dif && sk->sk_bound_dev_if != dif)
+ continue;
+
+ if (sk->sk_family != PF_INET6)
+ continue;
+
+ if (udp_sk(sk)->udp_port_hash != ntohs(sport))
+ continue;
+
+ if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, saddr) ||
+ !ipv6_addr_equal(&sk->sk_v6_daddr, daddr))
+ continue;
+
+ inet = inet_sk(sk);
+ if (inet->inet_dport != dport)
+ continue;
+
+ return sk;
+ }
+ }
+
+ return NULL;
+}
+EXPORT_SYMBOL(udp6_lib_lookup_full);
+
/*
* This should be easy, if there is something there we
* return it, otherwise we block.
@@ -1467,6 +1511,7 @@ struct proto udpv6_prot = {
.compat_getsockopt = compat_udpv6_getsockopt,
#endif
.clear_sk = udp_v6_clear_sk,
+ .diag_destroy = udp_abort,
};
static struct inet_protosw udpv6_protosw = {
--
2.1.4
