From 502cf9709036d9305495876fa8c33c8a52541b15 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 [ Upstream commit b096d97f47326b1e2dbdef1c91fab69ffda54d17 ] 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 Signed-off-by: Sasha Levin --- 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 d3f33194faf1..e7594a56cbfe 100644 --- a/fs/ksmbd/smb2pdu.c +++ b/fs/ksmbd/smb2pdu.c @@ -1862,8 +1862,11 @@ int smb2_sess_setup(struct ksmbd_work *work) 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); + } } }