From: Dan Carpenter <dan.carpenter@oracle.com>
To: Petr Vandrovec <petr@vandrovec.name>
Cc: devel@driverdev.osuosl.org, security@kernel.org,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
netdev@vger.kernel.org,
Philippe Ombredanne <pombredanne@nexb.com>,
Thomas Gleixner <tglx@linutronix.de>,
"David S. Miller" <davem@davemloft.net>
Subject: [PATCH] ncpfs: memory corruption in ncp_read_kernel()
Date: Mon, 19 Mar 2018 14:07:45 +0300 [thread overview]
Message-ID: <20180319110745.GA12001@mwanda> (raw)
In-Reply-To: <CA+ygN1LiXW3uNuMS-eRv5Y_WJNyyr77+Rgycec4Y-Ju2VGrNWA@mail.gmail.com>
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>
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);
next parent reply other threads:[~2018-03-19 11:07 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CA+ygN1LiXW3uNuMS-eRv5Y_WJNyyr77+Rgycec4Y-Ju2VGrNWA@mail.gmail.com>
2018-03-19 11:07 ` Dan Carpenter [this message]
2018-03-19 13:56 ` [PATCH] ncpfs: memory corruption in ncp_read_kernel() Greg Kroah-Hartman
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