From b096d97f47326b1e2dbdef1c91fab69ffda54d17 Mon Sep 17 00:00:00 2001 From: Namjae Jeon Date: Wed, 3 May 2023 08:43:30 +0900 Subject: [PATCH] ksmbd: block asynchronous requests when making a delay on session setup ksmbd make a delay of 5 seconds on session setup to avoid dictionary attacks. But the 5 seconds delay can be bypassed by using asynchronous requests. This patch block all requests on current connection when making a delay on sesstion setup failure. Cc: stable@vger.kernel.org Reported-by: zdi-disclosures@trendmicro.com # ZDI-CAN-20482 Signed-off-by: Namjae Jeon Signed-off-by: Steve French --- fs/ksmbd/smb2pdu.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c index 51cc1dfb92603..234ab5f4104f6 100644 --- a/fs/ksmbd/smb2pdu.c +++ b/fs/ksmbd/smb2pdu.c @@ -1840,8 +1840,11 @@ out_err: sess->last_active = jiffies; sess->state = SMB2_SESSION_EXPIRED; - if (try_delay) + if (try_delay) { + ksmbd_conn_set_need_reconnect(conn); ssleep(5); + ksmbd_conn_set_need_negotiate(conn); + } } } -- 2.30.2