From 7ae15a607bb106627859da621bd7543d44a6b61d Mon Sep 17 00:00:00 2001 From: Lorenzo Colitti Date: Wed, 16 Dec 2015 12:30:03 +0900 Subject: [PATCH] net: diag: Add the ability to destroy a socket. This patch adds a SOCK_DESTROY operation, a destroy function pointer to sock_diag_handler, and a diag_destroy function pointer. It does not include any implementation code. [backport of net-next 64be0aed59ad519d6f2160868734f7e278290ac1] Change-Id: Ic5327ff14b39dd268083ee4c1dc2c934b2820df5 Signed-off-by: Lorenzo Colitti Acked-by: Eric Dumazet Signed-off-by: David S. Miller --- include/linux/sock_diag.h | 2 ++ include/net/sock.h | 1 + include/uapi/linux/sock_diag.h | 1 + net/core/sock_diag.c | 23 ++++++++++++++++++++--- 4 files changed, 24 insertions(+), 3 deletions(-) diff --git a/include/linux/sock_diag.h b/include/linux/sock_diag.h index fddebc617469..4018b48f2b3b 100644 --- a/include/linux/sock_diag.h +++ b/include/linux/sock_diag.h @@ -15,6 +15,7 @@ struct sock_diag_handler { __u8 family; int (*dump)(struct sk_buff *skb, struct nlmsghdr *nlh); int (*get_info)(struct sk_buff *skb, struct sock *sk); + int (*destroy)(struct sk_buff *skb, struct nlmsghdr *nlh); }; int sock_diag_register(const struct sock_diag_handler *h); @@ -68,4 +69,5 @@ bool sock_diag_has_destroy_listeners(const struct sock *sk) } void sock_diag_broadcast_destroy(struct sock *sk); +int sock_diag_destroy(struct sock *sk, int err); #endif diff --git a/include/net/sock.h b/include/net/sock.h index 14d3c0734007..2d663ee8494d 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -1067,6 +1067,7 @@ struct proto { void (*destroy_cgroup)(struct mem_cgroup *memcg); struct cg_proto *(*proto_cgroup)(struct mem_cgroup *memcg); #endif + int (*diag_destroy)(struct sock *sk, int err); }; int proto_register(struct proto *prot, int alloc_slab); diff --git a/include/uapi/linux/sock_diag.h b/include/uapi/linux/sock_diag.h index 49230d36f9ce..84e66ed670be 100644 --- a/include/uapi/linux/sock_diag.h +++ b/include/uapi/linux/sock_diag.h @@ -4,6 +4,7 @@ #include #define SOCK_DIAG_BY_FAMILY 20 +#define SOCK_DESTROY_BACKPORT 21 struct sock_diag_req { __u8 sdiag_family; diff --git a/net/core/sock_diag.c b/net/core/sock_diag.c index 0c1d58d43f67..3963c3872c69 100644 --- a/net/core/sock_diag.c +++ b/net/core/sock_diag.c @@ -214,7 +214,7 @@ void sock_diag_unregister(const struct sock_diag_handler *hnld) } EXPORT_SYMBOL_GPL(sock_diag_unregister); -static int __sock_diag_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh) +static int __sock_diag_cmd(struct sk_buff *skb, struct nlmsghdr *nlh) { int err; struct sock_diag_req *req = nlmsg_data(nlh); @@ -234,8 +234,12 @@ static int __sock_diag_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh) hndl = sock_diag_handlers[req->sdiag_family]; if (hndl == NULL) err = -ENOENT; - else + else if (nlh->nlmsg_type == SOCK_DIAG_BY_FAMILY) err = hndl->dump(skb, nlh); + else if (nlh->nlmsg_type == SOCK_DESTROY_BACKPORT && hndl->destroy) + err = hndl->destroy(skb, nlh); + else + err = -EOPNOTSUPP; mutex_unlock(&sock_diag_table_mutex); return err; @@ -261,7 +265,8 @@ static int sock_diag_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh) return ret; case SOCK_DIAG_BY_FAMILY: - return __sock_diag_rcv_msg(skb, nlh); + case SOCK_DESTROY_BACKPORT: + return __sock_diag_cmd(skb, nlh); default: return -EINVAL; } @@ -295,6 +300,18 @@ static int sock_diag_bind(struct net *net, int group) return 0; } +int sock_diag_destroy(struct sock *sk, int err) +{ + if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) + return -EPERM; + + if (!sk->sk_prot->diag_destroy) + return -EOPNOTSUPP; + + return sk->sk_prot->diag_destroy(sk, err); +} +EXPORT_SYMBOL_GPL(sock_diag_destroy); + static int __net_init diag_net_init(struct net *net) { struct netlink_kernel_cfg cfg = { -- 2.34.1