From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 780892FCC04 for ; Tue, 14 Oct 2025 14:46:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760453211; cv=none; b=Fd9B18r1XhWjxECOQzjccZXroXIjSeuH08vdzqVvf4GdpTDDz1UCoJzvwUdz5E/4Xlprs8JeOe1ARDtz+n++79DTiYZ2R/CrhCR1iugVGyUoELPUE4fRRe332wPvZgOAgblLTiaYdvIXmmQYcg9qXN8BHklGoXS8cbeUEKhs6Ig= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760453211; c=relaxed/simple; bh=akDqgra0hrPzVfHQ6gGZXcua7Q5snQ6ZwH8C2E+NzfM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=EbZHbaSPmY7rBEofc3/rNjNvPPVdttAo13TCZPD707DwVwibKOXa7UdoGonBDuk+8vpalOWpvND92Evo5Ea4LfR510GEBzBjrkcAK0n5fv4Stz/UcOJeablPn51djFbmAOvqC/UjU3/5pQbvKxDf7eyLCU+67qAFrZFVMVggmcQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=V2IY7gce; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="V2IY7gce" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7B080C4CEE7; Tue, 14 Oct 2025 14:46:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1760453209; bh=akDqgra0hrPzVfHQ6gGZXcua7Q5snQ6ZwH8C2E+NzfM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=V2IY7gcev9n/mocutfXxUcEuh+iNShtxaXALgruVT3FClt9dBB2xc9oE9zBWiCyiy hkLzjfgEza6OtOblHK4Q+8dUdrjCa5plvZXeT5H3Z2+w1Hnz1580J/AimYV9qMblC4 VkhHiw35gTx7h6Y7aQ3DkSR68TFJ8TYLtiPJdDE4IvNzy5JKTFgMueEO/FJ/0YlTft cCEIvkiqZbsSoAgNK6JKo36k24IG1XebFpwaznAKi7ky67vQ9X7638ZE+CsRW5XxKp eLHjG2KYY0jHeIZCdCQqTjLilxbYWoe5QFN5bXYLw8+/vs+JSVmJ/RoWMQujhgr5kq hM8fmCHzfj/2Q== From: Sasha Levin To: stable@vger.kernel.org Cc: Namjae Jeon , Steve French , Sasha Levin Subject: [PATCH 6.6.y] ksmbd: add max ip connections parameter Date: Tue, 14 Oct 2025 10:46:46 -0400 Message-ID: <20251014144646.91722-1-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <2025101339-refocus-negotiate-7718@gregkh> References: <2025101339-refocus-negotiate-7718@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Namjae Jeon [ Upstream commit d8b6dc9256762293048bf122fc11c4e612d0ef5d ] This parameter set the maximum number of connections per ip address. The default is 8. Cc: stable@vger.kernel.org Fixes: c0d41112f1a5 ("ksmbd: extend the connection limiting mechanism to support IPv6") Signed-off-by: Namjae Jeon Signed-off-by: Steve French [ Adjust reserved room ] Signed-off-by: Sasha Levin --- fs/smb/server/ksmbd_netlink.h | 5 +++-- fs/smb/server/server.h | 1 + fs/smb/server/transport_ipc.c | 3 +++ fs/smb/server/transport_tcp.c | 28 +++++++++++++++++----------- 4 files changed, 24 insertions(+), 13 deletions(-) diff --git a/fs/smb/server/ksmbd_netlink.h b/fs/smb/server/ksmbd_netlink.h index f4e55199938d5..c6c1844d44482 100644 --- a/fs/smb/server/ksmbd_netlink.h +++ b/fs/smb/server/ksmbd_netlink.h @@ -108,10 +108,11 @@ struct ksmbd_startup_request { __u32 smb2_max_credits; /* MAX credits */ __u32 smbd_max_io_size; /* smbd read write size */ __u32 max_connections; /* Number of maximum simultaneous connections */ - __u32 reserved[126]; /* Reserved room */ + __u32 max_ip_connections; /* Number of maximum connection per ip address */ + __u32 reserved[125]; /* Reserved room */ __u32 ifc_list_sz; /* interfaces list size */ __s8 ____payload[]; -}; +} __packed; #define KSMBD_STARTUP_CONFIG_INTERFACES(s) ((s)->____payload) diff --git a/fs/smb/server/server.h b/fs/smb/server/server.h index 4d06f2eb0d6ad..d0744498ceed6 100644 --- a/fs/smb/server/server.h +++ b/fs/smb/server/server.h @@ -43,6 +43,7 @@ struct ksmbd_server_config { unsigned int auth_mechs; unsigned int max_connections; unsigned int max_inflight_req; + unsigned int max_ip_connections; char *conf[SERVER_CONF_WORK_GROUP + 1]; }; diff --git a/fs/smb/server/transport_ipc.c b/fs/smb/server/transport_ipc.c index 281101fd1f76f..80581a7bc1bcc 100644 --- a/fs/smb/server/transport_ipc.c +++ b/fs/smb/server/transport_ipc.c @@ -321,6 +321,9 @@ static int ipc_server_config_on_startup(struct ksmbd_startup_request *req) if (req->max_connections) server_conf.max_connections = req->max_connections; + if (req->max_ip_connections) + server_conf.max_ip_connections = req->max_ip_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); diff --git a/fs/smb/server/transport_tcp.c b/fs/smb/server/transport_tcp.c index 53c536f2ce9f9..c43a465114289 100644 --- a/fs/smb/server/transport_tcp.c +++ b/fs/smb/server/transport_tcp.c @@ -240,6 +240,7 @@ static int ksmbd_kthread_fn(void *p) struct interface *iface = (struct interface *)p; struct ksmbd_conn *conn; int ret; + unsigned int max_ip_conns; while (!kthread_should_stop()) { mutex_lock(&iface->sock_release_lock); @@ -257,34 +258,39 @@ static int ksmbd_kthread_fn(void *p) continue; } + if (!server_conf.max_ip_connections) + goto skip_max_ip_conns_limit; + /* * Limits repeated connections from clients with the same IP. */ + max_ip_conns = 0; down_read(&conn_list_lock); - list_for_each_entry(conn, &conn_list, conns_list) + list_for_each_entry(conn, &conn_list, conns_list) { #if IS_ENABLED(CONFIG_IPV6) if (client_sk->sk->sk_family == AF_INET6) { if (memcmp(&client_sk->sk->sk_v6_daddr, - &conn->inet6_addr, 16) == 0) { - ret = -EAGAIN; - break; - } + &conn->inet6_addr, 16) == 0) + max_ip_conns++; } else if (inet_sk(client_sk->sk)->inet_daddr == - conn->inet_addr) { - ret = -EAGAIN; - break; - } + conn->inet_addr) + max_ip_conns++; #else if (inet_sk(client_sk->sk)->inet_daddr == - conn->inet_addr) { + conn->inet_addr) + max_ip_conns++; +#endif + if (server_conf.max_ip_connections <= max_ip_conns) { ret = -EAGAIN; break; } -#endif + } up_read(&conn_list_lock); if (ret == -EAGAIN) continue; +skip_max_ip_conns_limit: + 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", -- 2.51.0