[PATCH] ksmbd: send proper error response in smb2_tree_connect()

From: Marios Makassikis <mmakassikis@freebox.fr>
To: linux-cifs@vger.kernel.org
Cc: Marios Makassikis <mmakassikis@freebox.fr>
Subject: [PATCH] ksmbd: send proper error response in smb2_tree_connect()
Date: Thu, 22 Dec 2022 11:47:02 +0100	[thread overview]
Message-ID: <20221222104701.717586-1-mmakassikis@freebox.fr> (raw)

Currently, smb2_tree_connect doesn't send an error response packet on
error.

This causes libsmb2 to skip the specific error code and fail with the
following:
 smb2_service failed with : Failed to parse fixed part of command
 payload. Unexpected size of Error reply. Expected 9, got 8

Signed-off-by: Marios Makassikis <mmakassikis@freebox.fr>
---
 fs/ksmbd/smb2pdu.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c
index 14d7f3599c63..bd2ff9ffa965 100644
--- a/fs/ksmbd/smb2pdu.c
+++ b/fs/ksmbd/smb2pdu.c
@@ -1882,12 +1882,14 @@ int smb2_tree_connect(struct ksmbd_work *work)
 	if (IS_ERR(treename)) {
 		pr_err("treename is NULL\n");
 		status.ret = KSMBD_TREE_CONN_STATUS_ERROR;
+		smb2_set_err_rsp(work);
 		goto out_err1;
 	}
 
 	name = ksmbd_extract_sharename(conn->um, treename);
 	if (IS_ERR(name)) {
 		status.ret = KSMBD_TREE_CONN_STATUS_ERROR;
+		smb2_set_err_rsp(work);
 		goto out_err1;
 	}
 
@@ -1895,10 +1897,12 @@ int smb2_tree_connect(struct ksmbd_work *work)
 		    name, treename);
 
 	status = ksmbd_tree_conn_connect(conn, sess, name);
-	if (status.ret == KSMBD_TREE_CONN_STATUS_OK)
+	if (status.ret == KSMBD_TREE_CONN_STATUS_OK) {
 		rsp->hdr.Id.SyncId.TreeId = cpu_to_le32(status.tree_conn->id);
-	else
+	} else {
+		smb2_set_err_rsp(work);
 		goto out_err1;
+	}
 
 	share = status.tree_conn->share_conf;
 	if (test_share_config_flag(share, KSMBD_SHARE_FLAG_PIPE)) {
@@ -1928,13 +1932,13 @@ int smb2_tree_connect(struct ksmbd_work *work)
 	if (conn->posix_ext_supported)
 		status.tree_conn->posix_extensions = true;
 
-out_err1:
 	rsp->StructureSize = cpu_to_le16(16);
+	inc_rfc1001_len(work->response_buf, 16);
+out_err1:
 	rsp->Capabilities = 0;
 	rsp->Reserved = 0;
 	/* default manual caching */
 	rsp->ShareFlags = SMB2_SHAREFLAG_MANUAL_CACHING;
-	inc_rfc1001_len(work->response_buf, 16);
 
 	if (!IS_ERR(treename))
 		kfree(treename);
-- 
2.25.1

