Patch "ksmbd: validate session id and tree id in compound request" has been added to the 6.4-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    ksmbd: validate session id and tree id in compound request

to the 6.4-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-validate-session-id-and-tree-id-in-compound-re.patch
and it can be found in the queue-6.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit d565655bbbb8310e4eed2f2c78a27bf1d9352f6e
Author: Namjae Jeon <linkinjeon@xxxxxxxxxx>
Date:   Sun Jul 23 15:21:11 2023 +0900

    ksmbd: validate session id and tree id in compound request
    
    [ Upstream commit 3df0411e132ee74a87aa13142dfd2b190275332e ]
    
    `smb2_get_msg()` in smb2_get_ksmbd_tcon() and smb2_check_user_session()
    will always return the first request smb2 header in a compound request.
    if `SMB2_TREE_CONNECT_HE` is the first command in compound request, will
    return 0, i.e. The tree id check is skipped.
    This patch use ksmbd_req_buf_next() to get current command in compound.
    
    Reported-by: zdi-disclosures@xxxxxxxxxxxxxx # ZDI-CAN-21506
    Signed-off-by: Namjae Jeon <linkinjeon@xxxxxxxxxx>
    Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/fs/smb/server/smb2pdu.c b/fs/smb/server/smb2pdu.c
index dab4c7d710914..ca5af2d9e28bb 100644
--- a/fs/smb/server/smb2pdu.c
+++ b/fs/smb/server/smb2pdu.c
@@ -87,9 +87,9 @@ struct channel *lookup_chann_list(struct ksmbd_session *sess, struct ksmbd_conn
  */
 int smb2_get_ksmbd_tcon(struct ksmbd_work *work)
 {
-	struct smb2_hdr *req_hdr = smb2_get_msg(work->request_buf);
+	struct smb2_hdr *req_hdr = ksmbd_req_buf_next(work);
 	unsigned int cmd = le16_to_cpu(req_hdr->Command);
-	int tree_id;
+	unsigned int tree_id;
 
 	if (cmd == SMB2_TREE_CONNECT_HE ||
 	    cmd ==  SMB2_CANCEL_HE ||
@@ -114,7 +114,7 @@ int smb2_get_ksmbd_tcon(struct ksmbd_work *work)
 			pr_err("The first operation in the compound does not have tcon\n");
 			return -EINVAL;
 		}
-		if (work->tcon->id != tree_id) {
+		if (tree_id != UINT_MAX && work->tcon->id != tree_id) {
 			pr_err("tree id(%u) is different with id(%u) in first operation\n",
 					tree_id, work->tcon->id);
 			return -EINVAL;
@@ -559,9 +559,9 @@ int smb2_allocate_rsp_buf(struct ksmbd_work *work)
  */
 int smb2_check_user_session(struct ksmbd_work *work)
 {
-	struct smb2_hdr *req_hdr = smb2_get_msg(work->request_buf);
+	struct smb2_hdr *req_hdr = ksmbd_req_buf_next(work);
 	struct ksmbd_conn *conn = work->conn;
-	unsigned int cmd = conn->ops->get_cmd_val(work);
+	unsigned int cmd = le16_to_cpu(req_hdr->Command);
 	unsigned long long sess_id;
 
 	/*
@@ -587,7 +587,7 @@ int smb2_check_user_session(struct ksmbd_work *work)
 			pr_err("The first operation in the compound does not have sess\n");
 			return -EINVAL;
 		}
-		if (work->sess->id != sess_id) {
+		if (sess_id != ULLONG_MAX && work->sess->id != sess_id) {
 			pr_err("session id(%llu) is different with the first operation(%lld)\n",
 					sess_id, work->sess->id);
 			return -EINVAL;