ksmbd: fix slab-out-of-bounds in smb2_allocate_rsp_buf

If ->ProtocolId is SMB2_TRANSFORM_PROTO_NUM, smb2 request size validation could be skipped. if request size is smaller than sizeof(struct smb2_query_info_req), slab-out-of-bounds read can happen in smb2_allocate_rsp_buf(). This patch allocate response buffer after decrypting transform request. smb3_decrypt_req() will validate transform request size and avoid slab-out-of-bound in smb2_allocate_rsp_buf(). Reported-by: Norbert Szetei <[email protected]> Signed-off-by: Namjae Jeon <[email protected]>
namjaejeon · Apr 16, 2024 · 2b15f0e · 2b15f0e
1 parent 10056ba
commit 2b15f0e
Showing 1 changed file with 5 additions and 8 deletions.
diff --git a/server.c b/server.c
@@ -167,20 +167,17 @@ static void __handle_ksmbd_work(struct ksmbd_work *work,
 	int rc;
 	bool is_chained = false;
 
-	if (conn->ops->allocate_rsp_buf(work))
-		return;
-
 	if (conn->ops->is_transform_hdr &&
 	    conn->ops->is_transform_hdr(work->request_buf)) {
 		rc = conn->ops->decrypt_req(work);
-		if (rc < 0) {
-			conn->ops->set_rsp_status(work, STATUS_DATA_ERROR);
-			goto send;
-		}
-
+		if (rc < 0)
+			return;
 		work->encrypted = true;
 	}
 
+	if (conn->ops->allocate_rsp_buf(work))
+		return;
+
 	rc = conn->ops->init_rsp_hdr(work);
 	if (rc) {
 		/* either uid or tid is not correct */