net: add sock_set_reuseaddr

Add a helper to directly set the SO_REUSEADDR sockopt from kernel space
without going through a fake uaccess.

For this the iscsi target now has to formally depend on inet to avoid
a mostly theoretical compile failure.  For actual operation it already
did depend on having ipv4 or ipv6 support.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/infiniband/sw/siw/siw_cm.c b/drivers/infiniband/sw/siw/siw_cm.c
index 559e5fd..d1860f3 100644 (file)
--- a/drivers/infiniband/sw/siw/siw_cm.c
+++ b/drivers/infiniband/sw/siw/siw_cm.c
@@ -1312,17 +1312,14 @@ static void siw_cm_llp_state_change(struct sock *sk)
 static int kernel_bindconnect(struct socket *s, struct sockaddr *laddr,
                              struct sockaddr *raddr)
 {
-       int rv, flags = 0, s_val = 1;
+       int rv, flags = 0;
        size_t size = laddr->sa_family == AF_INET ?
                sizeof(struct sockaddr_in) : sizeof(struct sockaddr_in6);
 
        /*
         * Make address available again asap.
         */
-       rv = kernel_setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (char *)&s_val,
-                              sizeof(s_val));
-       if (rv < 0)
-               return rv;
+       sock_set_reuseaddr(s->sk);
 
        rv = s->ops->bind(s, laddr, size);
        if (rv < 0)
@@ -1781,7 +1778,7 @@ int siw_create_listen(struct iw_cm_id *id, int backlog)
        struct siw_cep *cep = NULL;
        struct siw_device *sdev = to_siw_dev(id->device);
        int addr_family = id->local_addr.ss_family;
-       int rv = 0, s_val;
+       int rv = 0;
 
        if (addr_family != AF_INET && addr_family != AF_INET6)
                return -EAFNOSUPPORT;
@@ -1793,13 +1790,8 @@ int siw_create_listen(struct iw_cm_id *id, int backlog)
        /*
         * Allow binding local port when still in TIME_WAIT from last close.
         */
-       s_val = 1;
-       rv = kernel_setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (char *)&s_val,
-                              sizeof(s_val));
-       if (rv) {
-               siw_dbg(id->device, "setsockopt error: %d\n", rv);
-               goto error;
-       }
+       sock_set_reuseaddr(s->sk);
+
        if (addr_family == AF_INET) {
                struct sockaddr_in *laddr = &to_sockaddr_in(id->local_addr);
 

diff --git a/drivers/nvme/target/tcp.c b/drivers/nvme/target/tcp.c
index f0da04e..40757a6 100644 (file)
--- a/drivers/nvme/target/tcp.c
+++ b/drivers/nvme/target/tcp.c
@@ -1632,6 +1632,7 @@ static int nvmet_tcp_add_port(struct nvmet_port *nport)
        port->sock->sk->sk_user_data = port;
        port->data_ready = port->sock->sk->sk_data_ready;
        port->sock->sk->sk_data_ready = nvmet_tcp_listen_data_ready;
+       sock_set_reuseaddr(port->sock->sk);
 
        opt = 1;
        ret = kernel_setsockopt(port->sock, IPPROTO_TCP,
@@ -1641,13 +1642,6 @@ static int nvmet_tcp_add_port(struct nvmet_port *nport)
                goto err_sock;
        }
 
-       ret = kernel_setsockopt(port->sock, SOL_SOCKET, SO_REUSEADDR,
-                       (char *)&opt, sizeof(opt));
-       if (ret) {
-               pr_err("failed to set SO_REUSEADDR sock opt %d\n", ret);
-               goto err_sock;
-       }
-
        if (so_priority > 0) {
                ret = kernel_setsockopt(port->sock, SOL_SOCKET, SO_PRIORITY,
                                (char *)&so_priority, sizeof(so_priority));

diff --git a/drivers/target/iscsi/Kconfig b/drivers/target/iscsi/Kconfig
index 1f93ea3..922484e 100644 (file)
--- a/drivers/target/iscsi/Kconfig
+++ b/drivers/target/iscsi/Kconfig
@@ -1,7 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0-only
 config ISCSI_TARGET
        tristate "Linux-iSCSI.org iSCSI Target Mode Stack"
-       depends on NET
+       depends on INET
        select CRYPTO
        select CRYPTO_CRC32C
        select CRYPTO_CRC32C_INTEL if X86

diff --git a/drivers/target/iscsi/iscsi_target_login.c b/drivers/target/iscsi/iscsi_target_login.c
index 731ee67..91acb3f 100644 (file)
--- a/drivers/target/iscsi/iscsi_target_login.c
+++ b/drivers/target/iscsi/iscsi_target_login.c
@@ -909,14 +909,7 @@ int iscsit_setup_np(
                }
        }
 
-       /* FIXME: Someone please explain why this is endian-safe */
-       ret = kernel_setsockopt(sock, SOL_SOCKET, SO_REUSEADDR,
-                       (char *)&opt, sizeof(opt));
-       if (ret < 0) {
-               pr_err("kernel_setsockopt() for SO_REUSEADDR"
-                       " failed\n");
-               goto fail;
-       }
+       sock_set_reuseaddr(sock->sk);
 
        ret = kernel_setsockopt(sock, IPPROTO_IP, IP_FREEBIND,
                        (char *)&opt, sizeof(opt));

diff --git a/fs/dlm/lowcomms.c b/fs/dlm/lowcomms.c
index f13dad0..88f2574 100644 (file)
--- a/fs/dlm/lowcomms.c
+++ b/fs/dlm/lowcomms.c
@@ -1127,12 +1127,8 @@ static struct socket *tcp_create_listen_sock(struct connection *con,
        kernel_setsockopt(sock, SOL_TCP, TCP_NODELAY, (char *)&one,
                          sizeof(one));
 
-       result = kernel_setsockopt(sock, SOL_SOCKET, SO_REUSEADDR,
-                                  (char *)&one, sizeof(one));
+       sock_set_reuseaddr(sock->sk);
 
-       if (result < 0) {
-               log_print("Failed to set SO_REUSEADDR on socket: %d", result);
-       }
        write_lock_bh(&sock->sk->sk_callback_lock);
        sock->sk->sk_user_data = con;
        save_listen_callbacks(sock);

diff --git a/include/net/sock.h b/include/net/sock.h
index 3e8c6d4..2ec0850 100644 (file)
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -2688,4 +2688,6 @@ static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif)
 
 void sock_def_readable(struct sock *sk);
 
+void sock_set_reuseaddr(struct sock *sk);
+
 #endif /* _SOCK_H */

diff --git a/net/core/sock.c b/net/core/sock.c
index fd85e65..18eb84f 100644 (file)
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -712,6 +712,14 @@ bool sk_mc_loop(struct sock *sk)
 }
 EXPORT_SYMBOL(sk_mc_loop);
 
+void sock_set_reuseaddr(struct sock *sk)
+{
+       lock_sock(sk);
+       sk->sk_reuse = SK_CAN_REUSE;
+       release_sock(sk);
+}
+EXPORT_SYMBOL(sock_set_reuseaddr);
+
 /*
  *     This is meant for all protocols to use and covers goings on
  *     at the socket level. Everything here is generic.