diff --git a/fs/nfs/callback_xdr.c b/fs/nfs/callback_xdr.c
index 726e59a9e50f6ad20471895793efdb171aed7dd7..d50b2742f23baeb20d54c44d6919ed126faf74c8 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) {