From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Thu, 12 Jan 2012 07:16:14 +0000 (+0300)
Subject: nfs: check for integer overflow in decode_devicenotify_args()
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=363e0df057ea8da539645fe4c3c227e3d44054cc;p=linux-beck.git

nfs: check for integer overflow in decode_devicenotify_args()

On 32 bit, if n is too large then "n * sizeof(*args->devs)" could
overflow and args->devs would be smaller than expected.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
---

diff --git a/fs/nfs/callback_xdr.c b/fs/nfs/callback_xdr.c
index 726e59a9e50f..d50b2742f23b 100644
--- a/fs/nfs/callback_xdr.c
+++ b/fs/nfs/callback_xdr.c
@@ -305,6 +305,10 @@ __be32 decode_devicenotify_args(struct svc_rqst *rqstp,
 	n = ntohl(*p++);
 	if (n <= 0)
 		goto out;
+	if (n > ULONG_MAX / sizeof(*args->devs)) {
+		status = htonl(NFS4ERR_BADXDR);
+		goto out;
+	}
 
 	args->devs = kmalloc(n * sizeof(*args->devs), GFP_KERNEL);
 	if (!args->devs) {