From 235aa674d87944381e7b279cd1158b55b0f1bfa8 Mon Sep 17 00:00:00 2001 From: Namjae Jeon Date: Mon, 2 Oct 2023 09:39:21 +0900 Subject: [PATCH] ksmbd: fix race condition from parallel smb2 logoff requests If parallel smb2 logoff requests come in before closing door, running request count becomes more than 1 even though connection status is set to KSMBD_SESS_NEED_RECONNECT. It can't get condition true, and sleep forever. This patch fix race condition problem by returning error if connection status was already set to KSMBD_SESS_NEED_RECONNECT. Signed-off-by: Namjae Jeon --- smb2pdu.c | 24 ++++++++++++++++-------- 1 file changed, 16 insertions(+), 8 deletions(-) diff --git a/smb2pdu.c b/smb2pdu.c index de5de1062..868df32ed 100644 --- a/smb2pdu.c +++ b/smb2pdu.c @@ -2181,17 +2181,17 @@ int smb2_session_logoff(struct ksmbd_work *work) ksmbd_debug(SMB, "request\n"); - sess_id = le64_to_cpu(req->hdr.SessionId); - - rsp->StructureSize = cpu_to_le16(4); - err = ksmbd_iov_pin_rsp(work, rsp, sizeof(struct smb2_logoff_rsp)); - if (err) { - rsp->hdr.Status = STATUS_INSUFFICIENT_RESOURCES; + ksmbd_conn_lock(conn); + if (!ksmbd_conn_good(conn)) { + ksmbd_conn_unlock(conn); + rsp->hdr.Status = STATUS_NETWORK_NAME_DELETED; smb2_set_err_rsp(work); - return err; + return -ENOENT; } - + sess_id = le64_to_cpu(req->hdr.SessionId); ksmbd_all_conn_set_status(sess_id, KSMBD_SESS_NEED_RECONNECT); + ksmbd_conn_unlock(conn); + ksmbd_close_session_fds(work); ksmbd_conn_wait_idle(conn, sess_id); @@ -2213,6 +2213,14 @@ int smb2_session_logoff(struct ksmbd_work *work) ksmbd_free_user(sess->user); sess->user = NULL; ksmbd_all_conn_set_status(sess_id, KSMBD_SESS_NEED_NEGOTIATE); + + rsp->StructureSize = cpu_to_le16(4); + err = ksmbd_iov_pin_rsp(work, rsp, sizeof(struct smb2_logoff_rsp)); + if (err) { + rsp->hdr.Status = STATUS_INSUFFICIENT_RESOURCES; + smb2_set_err_rsp(work); + return err; + } return 0; }