From aa0ae7368979a89e99113a023a46486ece2df24c Mon Sep 17 00:00:00 2001
From: Zhang Wei <zhangwei519@huawei.com>
Date: Sat, 22 Apr 2017 19:19:24 +0800
Subject: [PATCH] net: diag: support SOCK_DESTROY for UDP sockets
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.
[backport of net-next 5d77dca82839ef016a93ad7acd7058b14d967752]
Change-Id: I84e71e774c859002f98dcdb5e0ca01f35227a44c
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
include/net/udp.h | 1 +
net/ipv4/udp.c | 15 +++++++++
net/ipv4/udp_diag.c | 80 +++++++++++++++++++++++++++++++++++++++++++++
net/ipv6/udp.c | 1 +
4 files changed, 97 insertions(+)
diff --git a/include/net/udp.h b/include/net/udp.h
index ad99eedc6168..7b5837f22a38 100644
--- a/include/net/udp.h
+++ b/include/net/udp.h
@@ -179,6 +179,7 @@ extern int udp_get_port(struct sock *sk, unsigned short snum,
int (*saddr_cmp)(const struct sock *,
const struct sock *));
extern void udp_err(struct sk_buff *, u32);
+int udp_abort(struct sock *sk, int err);
extern int udp_sendmsg(struct kiocb *iocb, struct sock *sk,
struct msghdr *msg, size_t len);
extern int udp_push_pending_frames(struct sock *sk);
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index f03dac162855..eb6ccdb6cda6 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -1977,6 +1977,20 @@ 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);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(udp_abort);
+
struct proto udp_prot = {
.name = "UDP",
.owner = THIS_MODULE,
@@ -2008,6 +2022,7 @@ 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 7927db0a9279..f4eb259f6318 100644
--- a/net/ipv4/udp_diag.c
+++ b/net/ipv4/udp_diag.c
@@ -16,6 +16,7 @@
#include <net/udp.h>
#include <net/udplite.h>
#include <linux/sock_diag.h>
+#include <net/ipv6.h>
static int sk_diag_dump(struct sock *sk, struct sk_buff *skb,
struct netlink_callback *cb, struct inet_diag_req_v2 *req,
@@ -160,11 +161,87 @@ 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;
+ int err;
+
+ rcu_read_lock();
+
+ if (req->sdiag_family == AF_INET)
+ sk = __udp4_lib_lookup(net,
+ req->id.idiag_dst[0], req->id.idiag_dport,
+ req->id.idiag_src[0], req->id.idiag_sport,
+ req->id.idiag_if, tbl);
+#if IS_ENABLED(CONFIG_IPV6)
+ else if (req->sdiag_family == AF_INET6) {
+ if (ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_dst) &&
+ ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_src))
+ sk = __udp4_lib_lookup(net,
+ req->id.idiag_dst[0], req->id.idiag_dport,
+ req->id.idiag_src[0], req->id.idiag_sport,
+ req->id.idiag_if, tbl);
+
+ else
+ sk = __udp6_lib_lookup(net,
+ (struct in6_addr *)req->id.idiag_dst,
+ req->id.idiag_dport,
+ (struct in6_addr *)req->id.idiag_src,
+ req->id.idiag_sport,
+ req->id.idiag_if, tbl);
+ }
+#endif
+ else {
+ rcu_read_unlock();
+ return -EINVAL;
+ }
+
+ if (sk && !atomic_inc_not_zero(&sk->sk_refcnt))
+ sk = NULL;
+
+ rcu_read_unlock();
+
+ if (!sk)
+ return -ENOENT;
+
+ if (sock_diag_check_cookie(sk, (__u32 *) req->id.idiag_cookie)) {
+ sock_put(sk);
+ return -ENOENT;
+ }
+
+ err = sock_diag_destroy(sk, ECONNABORTED);
+
+ sock_put(sk);
+
+ return err;
+}
+
+static int udp_diag_destroy(struct sk_buff *in_skb,
+ 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,
+ 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,
+#ifdef CONFIG_INET_DIAG_DESTROY
+ .destroy = udp_diag_destroy,
+#endif
};
static void udplite_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
@@ -184,6 +261,9 @@ static const struct inet_diag_handler udplite_diag_handler = {
.dump_one = udplite_diag_dump_one,
.idiag_get_info = udp_diag_get_info,
.idiag_type = IPPROTO_UDPLITE,
+#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 b5374d87debb..184a9d239622 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -1481,6 +1481,7 @@ 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 = {
--
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