From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CC79AC54EAA for ; Mon, 30 Jan 2023 14:18:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237576AbjA3OSC (ORCPT ); Mon, 30 Jan 2023 09:18:02 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33030 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237366AbjA3ORf (ORCPT ); Mon, 30 Jan 2023 09:17:35 -0500 Received: from sin.source.kernel.org (sin.source.kernel.org [IPv6:2604:1380:40e1:4800::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2E13F3E617 for ; Mon, 30 Jan 2023 06:17:06 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sin.source.kernel.org (Postfix) with ESMTPS id 5D3ECCE16BA for ; Mon, 30 Jan 2023 14:17:04 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 224AAC4339C; Mon, 30 Jan 2023 14:17:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1675088222; bh=BLPU/h1OVwpyyXRbJPfv6bho7zCl8sAoPAbsZxcMUWo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=g4YEch/WFseDe8gqQNm5C/dJjIrzdzKfMqjSKeD7aJ846ugB2vByxtvxOlXXwvnsW 7KZsP+6KCorJbP8dPYuilrkOCii/dG0bYjr5Hux93Xm8ffwgl7oyF9GcTIKeJ47+xi 8iusNXUxn27tSkDdfetDTAfnA5cBginqLmo0/IWg= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Marios Makassikis , Namjae Jeon , Steve French Subject: [PATCH 5.15 156/204] ksmbd: do not sign response to session request for guest login Date: Mon, 30 Jan 2023 14:52:01 +0100 Message-Id: <20230130134323.400272950@linuxfoundation.org> X-Mailer: git-send-email 2.39.1 In-Reply-To: <20230130134316.327556078@linuxfoundation.org> References: <20230130134316.327556078@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Marios Makassikis commit 5fde3c21cf33830eda7bfd006dc7f4bf07ec9fe6 upstream. If ksmbd.mountd is configured to assign unknown users to the guest account ("map to guest = bad user" in the config), ksmbd signs the response. This is wrong according to MS-SMB2 3.3.5.5.3: 12. If the SMB2_SESSION_FLAG_IS_GUEST bit is not set in the SessionFlags field, and Session.IsAnonymous is FALSE, the server MUST sign the final session setup response before sending it to the client, as follows: [...] This fixes libsmb2 based applications failing to establish a session ("Wrong signature in received"). Fixes: e2f34481b24d ("cifsd: add server-side procedures for SMB3") Cc: stable@vger.kernel.org Signed-off-by: Marios Makassikis Acked-by: Namjae Jeon Signed-off-by: Steve French Signed-off-by: Greg Kroah-Hartman --- fs/ksmbd/smb2pdu.c | 2 ++ 1 file changed, 2 insertions(+) --- a/fs/ksmbd/smb2pdu.c +++ b/fs/ksmbd/smb2pdu.c @@ -8613,6 +8613,7 @@ int smb3_decrypt_req(struct ksmbd_work * bool smb3_11_final_sess_setup_resp(struct ksmbd_work *work) { struct ksmbd_conn *conn = work->conn; + struct ksmbd_session *sess = work->sess; struct smb2_hdr *rsp = work->response_buf; if (conn->dialect < SMB30_PROT_ID) @@ -8622,6 +8623,7 @@ bool smb3_11_final_sess_setup_resp(struc rsp = ksmbd_resp_buf_next(work); if (le16_to_cpu(rsp->Command) == SMB2_SESSION_SETUP_HE && + sess->user && !user_guest(sess->user) && rsp->Status == STATUS_SUCCESS) return true; return false;