ksmbd: add max connections parameter

Add max connections parameter to limit number of maximum simultaneous
connections.

Fixes: 0626e6641f ("cifsd: add server handler for central processing and tranport layers")
Cc: stable@vger.kernel.org
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
This commit is contained in:
Namjae Jeon 2022-12-29 18:33:25 +09:00 committed by Steve French
parent 5dc4c995db
commit 0d0d4680db
4 changed files with 22 additions and 2 deletions

View File

@ -106,7 +106,8 @@ struct ksmbd_startup_request {
__u32 sub_auth[3]; /* Subauth value for Security ID */
__u32 smb2_max_credits; /* MAX credits */
__u32 smbd_max_io_size; /* smbd read write size */
__u32 reserved[127]; /* Reserved room */
__u32 max_connections; /* Number of maximum simultaneous connections */
__u32 reserved[126]; /* Reserved room */
__u32 ifc_list_sz; /* interfaces list size */
__s8 ____payload[];
};

View File

@ -41,6 +41,7 @@ struct ksmbd_server_config {
unsigned int share_fake_fscaps;
struct smb_sid domain_sid;
unsigned int auth_mechs;
unsigned int max_connections;
char *conf[SERVER_CONF_WORK_GROUP + 1];
};

View File

@ -308,6 +308,9 @@ static int ipc_server_config_on_startup(struct ksmbd_startup_request *req)
if (req->smbd_max_io_size)
init_smbd_max_io_size(req->smbd_max_io_size);
if (req->max_connections)
server_conf.max_connections = req->max_connections;
ret = ksmbd_set_netbios_name(req->netbios_name);
ret |= ksmbd_set_server_string(req->server_string);
ret |= ksmbd_set_work_group(req->work_group);

View File

@ -15,6 +15,8 @@
#define IFACE_STATE_DOWN BIT(0)
#define IFACE_STATE_CONFIGURED BIT(1)
static atomic_t active_num_conn;
struct interface {
struct task_struct *ksmbd_kthread;
struct socket *ksmbd_socket;
@ -185,8 +187,10 @@ static int ksmbd_tcp_new_connection(struct socket *client_sk)
struct tcp_transport *t;
t = alloc_transport(client_sk);
if (!t)
if (!t) {
sock_release(client_sk);
return -ENOMEM;
}
csin = KSMBD_TCP_PEER_SOCKADDR(KSMBD_TRANS(t)->conn);
if (kernel_getpeername(client_sk, csin) < 0) {
@ -239,6 +243,15 @@ static int ksmbd_kthread_fn(void *p)
continue;
}
if (server_conf.max_connections &&
atomic_inc_return(&active_num_conn) >= server_conf.max_connections) {
pr_info_ratelimited("Limit the maximum number of connections(%u)\n",
atomic_read(&active_num_conn));
atomic_dec(&active_num_conn);
sock_release(client_sk);
continue;
}
ksmbd_debug(CONN, "connect success: accepted new connection\n");
client_sk->sk->sk_rcvtimeo = KSMBD_TCP_RECV_TIMEOUT;
client_sk->sk->sk_sndtimeo = KSMBD_TCP_SEND_TIMEOUT;
@ -368,6 +381,8 @@ static int ksmbd_tcp_writev(struct ksmbd_transport *t, struct kvec *iov,
static void ksmbd_tcp_disconnect(struct ksmbd_transport *t)
{
free_transport(TCP_TRANS(t));
if (server_conf.max_connections)
atomic_dec(&active_num_conn);
}
static void tcp_destroy_socket(struct socket *ksmbd_socket)