From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: Re: [PATCH v3 net-next] net: diag: support SOCK_DESTROY for UDP sockets Date: Tue, 23 Aug 2016 08:55:10 -0700 Message-ID: <1471967710.14381.23.camel@edumazet-glaptop3.roam.corp.google.com> References: <1471964547-18098-1-git-send-email-dsa@cumulusnetworks.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, Lorenzo Colitti To: David Ahern Return-path: Received: from mail-pa0-f66.google.com ([209.85.220.66]:33901 "EHLO mail-pa0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753830AbcHWPzM (ORCPT ); Tue, 23 Aug 2016 11:55:12 -0400 Received: by mail-pa0-f66.google.com with SMTP id hh10so10165624pac.1 for ; Tue, 23 Aug 2016 08:55:12 -0700 (PDT) In-Reply-To: <1471964547-18098-1-git-send-email-dsa@cumulusnetworks.com> Sender: netdev-owner@vger.kernel.org List-ID: On Tue, 2016-08-23 at 08:02 -0700, David Ahern wrote: > 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. > > Signed-off-by: David Ahern > --- > v3 > - add missing sock_diag_check_cookie check after socket lookup per > Eric'c comment > > v2 > - changed socket lookup to __udp{4,6}_lib_lookup > > include/net/udp.h | 1 + > net/ipv4/udp.c | 17 +++++++++++++++ > net/ipv4/udp_diag.c | 60 +++++++++++++++++++++++++++++++++++++++++++++++++++++ > net/ipv6/udp.c | 1 + > 4 files changed, 79 insertions(+) > > diff --git a/include/net/udp.h b/include/net/udp.h > index 8894d7144189..ea53a87d880f 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); > diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c > index 8f5f7f6026f7..044058835ea8 100644 > --- a/net/ipv4/udp.c > +++ b/net/ipv4/udp.c > @@ -2193,6 +2193,22 @@ 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, > @@ -2224,6 +2240,7 @@ 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..63896dd766f3 100644 > --- a/net/ipv4/udp_diag.c > +++ b/net/ipv4/udp_diag.c > @@ -165,12 +165,69 @@ 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(net, > + req->id.idiag_dst[0], req->id.idiag_dport, > + req->id.idiag_src[0], req->id.idiag_sport, > + req->id.idiag_if, tbl, NULL); > +#if IS_ENABLED(CONFIG_IPV6) > + else if (req->sdiag_family == AF_INET6) > + 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, NULL); > +#endif > + if (sk && !atomic_inc_not_zero(&sk->sk_refcnt)) > + sk = NULL; > + > + rcu_read_unlock(); > + > + if (!sk) > + return -ENOENT; > + > + if (sock_diag_check_cookie(sk, req->id.idiag_cookie)) { > + sock_put(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 +249,9 @@ 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..16512cf06e73 100644 > --- a/net/ipv6/udp.c > +++ b/net/ipv6/udp.c > @@ -1467,6 +1467,7 @@ 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 = {