nfs: check for integer overflow in decode_devicenotify_args()
authorDan Carpenter <dan.carpenter@oracle.com>
Thu, 12 Jan 2012 07:16:14 +0000 (10:16 +0300)
committerTrond Myklebust <Trond.Myklebust@netapp.com>
Thu, 12 Jan 2012 21:30:07 +0000 (16:30 -0500)
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>
fs/nfs/callback_xdr.c

index 726e59a..d50b274 100644 (file)
@@ -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) {