If the server is malicious then *bytes_read could be larger than the
size of the "target" buffer. It would lead to memory corruption when we
do the memcpy().
Reported-by: Dr Silvio Cesare of InfoSect <Silvio Cesare
<silvio.ces...@gmail.com>
Signed-off-by: Dan Carpenter <dan.carpen...@oracle.com>
diff --git a/drivers/staging/ncpfs/ncplib_kernel.c
b/drivers/staging/ncpfs/ncplib_kernel.c
index 804adfebba2f..3e047eb4cc7c 100644
--- a/drivers/staging/ncpfs/ncplib_kernel.c
+++ b/drivers/staging/ncpfs/ncplib_kernel.c
@@ -981,6 +981,10 @@ ncp_read_kernel(struct ncp_server *server, const char
*file_id,
goto out;
}
*bytes_read = ncp_reply_be16(server, 0);
+ if (*bytes_read > to_read) {
+ result = -EINVAL;
+ goto out;
+ }
source = ncp_reply_data(server, 2 + (offset & 1));
memcpy(target, source, *bytes_read);