Commit 2a2b9ef3 authored Mar 19, 2018 by Dan Carpenter Committed by Greg Kroah-Hartman Mar 28, 2018

staging: ncpfs: memory corruption in ncp_read_kernel()



commit 4c41aa24baa4ed338241d05494f2c595c885af8f upstream.

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 &lt;Silvio Cesare <silvio.cesare@gmail.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 3f3a6707

fs/ncpfs/ncplib_kernel.c

+4 −0

Original line number	Diff line number	Diff line
		@@ -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);