From cf3a4f1e86ecdd24f87b615051b49d8e1968c230 Mon Sep 17 00:00:00 2001 From: "liucheng (G)" Date: Thu, 29 Aug 2019 13:47:54 +0000 Subject: [PATCH] CVE-2019-14195: nfs: fix unbounded memcpy with unvalidated length at nfs_readlink_reply MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit This patch adds a check to rpc_pkt.u.reply.data at nfs_readlink_reply. Signed-off-by: Cheng Liu Reported-by: Fermín Serna Acked-by: Joe Hershberger --- net/nfs.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/nfs.c b/net/nfs.c index 11941fad1a..915acd95cf 100644 --- a/net/nfs.c +++ b/net/nfs.c @@ -634,6 +634,9 @@ static int nfs_readlink_reply(uchar *pkt, unsigned len) /* new path length */ rlen = ntohl(rpc_pkt.u.reply.data[1 + nfsv3_data_offset]); + if (((uchar *)&(rpc_pkt.u.reply.data[0]) - (uchar *)(&rpc_pkt) + rlen) > len) + return -NFS_RPC_DROP; + if (*((char *)&(rpc_pkt.u.reply.data[2 + nfsv3_data_offset])) != '/') { int pathlen; -- 2.25.1