From 12a6680ce59bcd431730c9f049caddb017964c64 Mon Sep 17 00:00:00 2001 From: Namjae Jeon Date: Thu, 13 Aug 2026 17:05:49 +0900 Subject: [PATCH] ksmbd: disconnect on SMB3 decryption failure MS-SMB2 requires the server to disconnect a connection when an encrypted transform cannot be associated with a session or fails authenticated decryption. This includes an encrypted request that still carries a SessionId invalidated through PreviousSessionId. Move the connection to EXITING and shut down its transport when decrypt_req() fails. Add the missing TCP shutdown callback so a receive blocked in kernel_recvmsg() is released; SMB Direct already provides the corresponding callback. Plaintext requests using an invalidated SessionId do not take this path and continue to receive STATUS_USER_SESSION_DELETED. Fixes: e2f34481b24d ("cifsd: add server-side procedures for SMB3") Signed-off-by: Namjae Jeon --- fs/smb/server/connection.c | 16 ++++++++++++++++ fs/smb/server/connection.h | 1 + fs/smb/server/server.c | 4 +++- fs/smb/server/transport_tcp.c | 6 ++++++ 4 files changed, 26 insertions(+), 1 deletion(-) diff --git a/fs/smb/server/connection.c b/fs/smb/server/connection.c index 71d55d903f6f..5d729473dd18 100644 --- a/fs/smb/server/connection.c +++ b/fs/smb/server/connection.c @@ -439,6 +439,22 @@ void ksmbd_all_conn_set_status(struct ksmbd_session *sess, u32 status) up_read(&conn_list_lock); } +void ksmbd_conn_abort(struct ksmbd_conn *conn) +{ + bool shutdown = false; + + spin_lock(&conn->request_lock); + if (!ksmbd_conn_exiting(conn) && !ksmbd_conn_releasing(conn)) { + ksmbd_conn_set_exiting(conn); + shutdown = true; + } + spin_unlock(&conn->request_lock); + wake_up_all(&conn->req_running_q); + + if (shutdown && conn->transport->ops->shutdown) + conn->transport->ops->shutdown(conn->transport); +} + void ksmbd_conn_wait_idle(struct ksmbd_conn *conn) { wait_event(conn->req_running_q, atomic_read(&conn->req_running) < 2); diff --git a/fs/smb/server/connection.h b/fs/smb/server/connection.h index c01ccbe8b97c..421907aed473 100644 --- a/fs/smb/server/connection.h +++ b/fs/smb/server/connection.h @@ -203,6 +203,7 @@ struct ksmbd_conn *ksmbd_conn_alloc(void); void ksmbd_conn_free(struct ksmbd_conn *conn); struct ksmbd_conn *ksmbd_conn_get(struct ksmbd_conn *conn); void ksmbd_conn_put(struct ksmbd_conn *conn); +void ksmbd_conn_abort(struct ksmbd_conn *conn); int ksmbd_conn_wq_init(void); void ksmbd_conn_wq_destroy(void); bool ksmbd_conn_lookup_dialect(struct ksmbd_conn *c); diff --git a/fs/smb/server/server.c b/fs/smb/server/server.c index 7881fc7bb8cd..ba44bea9ddc3 100644 --- a/fs/smb/server/server.c +++ b/fs/smb/server/server.c @@ -188,8 +188,10 @@ static void __handle_ksmbd_work(struct ksmbd_work *work, if (conn->ops->is_transform_hdr && conn->ops->is_transform_hdr(work->request_buf)) { rc = conn->ops->decrypt_req(work); - if (rc < 0) + if (rc < 0) { + ksmbd_conn_abort(conn); return; + } work->encrypted = true; } diff --git a/fs/smb/server/transport_tcp.c b/fs/smb/server/transport_tcp.c index 1045eca581c3..0ae5f145a332 100644 --- a/fs/smb/server/transport_tcp.c +++ b/fs/smb/server/transport_tcp.c @@ -435,6 +435,11 @@ static void ksmbd_tcp_disconnect(struct ksmbd_transport *t) atomic_dec(&active_num_conn); } +static void ksmbd_tcp_shutdown(struct ksmbd_transport *t) +{ + kernel_sock_shutdown(TCP_TRANS(t)->sock, SHUT_RDWR); +} + static void tcp_destroy_socket(struct socket *ksmbd_socket) { int ret; @@ -681,5 +686,6 @@ static const struct ksmbd_transport_ops ksmbd_tcp_transport_ops = { .read = ksmbd_tcp_read, .writev = ksmbd_tcp_writev, .disconnect = ksmbd_tcp_disconnect, + .shutdown = ksmbd_tcp_shutdown, .free_transport = ksmbd_tcp_free_transport, };