diff options
author | Dan Carpenter <dan.carpenter@oracle.com> | 2018-03-19 14:07:45 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-03-28 18:23:01 +0200 |
commit | 9a6730ae707b16b038f3731f93f67aa0bd08017f (patch) | |
tree | 517355003dad310df1fe7aef4d3fd2787c9cd3a3 | |
parent | 7b6f657ad598b5dd561a7309290082a4b9f0dfb9 (diff) |
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 <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>
-rw-r--r-- | fs/ncpfs/ncplib_kernel.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/fs/ncpfs/ncplib_kernel.c b/fs/ncpfs/ncplib_kernel.c index 804adfebba2f..3e047eb4cc7c 100644 --- a/fs/ncpfs/ncplib_kernel.c +++ b/fs/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); |