This is a note to let you know that I've just added the patch titled
ksmbd: block asynchronous requests when making a delay on session setup
to the 6.3-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
ksmbd-block-asynchronous-requests-when-making-a-delay-on-session-setup.patch
and it can be found in the queue-6.3 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From b096d97f47326b1e2dbdef1c91fab69ffda54d17 Mon Sep 17 00:00:00 2001
From: Namjae Jeon <linkinjeon@xxxxxxxxxx>
Date: Wed, 3 May 2023 08:43:30 +0900
Subject: ksmbd: block asynchronous requests when making a delay on session setup
From: Namjae Jeon <linkinjeon@xxxxxxxxxx>
commit b096d97f47326b1e2dbdef1c91fab69ffda54d17 upstream.
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@xxxxxxxxxxxxxxx
Reported-by: zdi-disclosures@xxxxxxxxxxxxxx # ZDI-CAN-20482
Signed-off-by: Namjae Jeon <linkinjeon@xxxxxxxxxx>
Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/ksmbd/smb2pdu.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
--- a/fs/ksmbd/smb2pdu.c
+++ b/fs/ksmbd/smb2pdu.c
@@ -1874,8 +1874,11 @@ out_err:
try_delay = true;
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);
+ }
}
}
Patches currently in stable-queue which might be from linkinjeon@xxxxxxxxxx are
queue-6.3/ksmbd-block-asynchronous-requests-when-making-a-delay-on-session-setup.patch
queue-6.3/ksmbd-not-allow-guest-user-on-multichannel.patch
queue-6.3/ksmbd-fix-racy-issue-from-smb2-close-and-logoff-with-multichannel.patch
queue-6.3/ksmbd-fix-memleak-in-session-setup.patch
queue-6.3/ksmbd-fix-null-pointer-dereference-in-smb2_get_info_filesystem.patch
queue-6.3/ksmbd-fix-racy-issue-from-session-setup-and-logoff.patch
queue-6.3/ksmbd-fix-racy-issue-under-cocurrent-smb2-tree-disconnect.patch
queue-6.3/ksmbd-fix-deadlock-in-ksmbd_find_crypto_ctx.patch
queue-6.3/ksmbd-destroy-expired-sessions.patch
queue-6.3/ksmbd-call-rcu_barrier-in-ksmbd_server_exit.patch
