crypto: nx - off by one bug in nx_of_update_msc()

commit e514cc0a upstream.

The props->ap[] array is defined like this:

	struct alg_props ap[NX_MAX_FC][NX_MAX_MODE][3];

So we can see that if msc->fc and msc->mode are == to NX_MAX_FC or
NX_MAX_MODE then we're off by one.

Fixes: ae0222b7 ('powerpc/crypto: nx driver code supporting nx encryption')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

drivers/crypto/nx/nx.c

@@ -330,7 +330,7 @@ static void nx_of_update_msc(struct device   *dev,
 		     ((bytes_so_far + sizeof(struct msc_triplet)) <= lenp) &&
 		     i < msc->triplets;
 		     i++) {
-			if (msc->fc > NX_MAX_FC || msc->mode > NX_MAX_MODE) {
+			if (msc->fc >= NX_MAX_FC || msc->mode >= NX_MAX_MODE) {
 				dev_err(dev, "unknown function code/mode "
 					"combo: %d/%d (ignored)\n", msc->fc,
 					msc->mode);