tehuti: check register size

Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/net/tehuti.c b/drivers/net/tehuti.c
index 17585e5..d2e1b219 100644
--- a/drivers/net/tehuti.c
+++ b/drivers/net/tehuti.c
@@ -625,6 +625,12 @@
 		s_firmLoad[i] = CPU_CHIP_SWAP32(s_firmLoad[i]);
 }
 
+static int bdx_range_check(struct bdx_priv *priv, u32 offset)
+{
+	return (offset > (u32) (BDX_REGS_SIZE / priv->nic->port_num)) ?
+		-EINVAL : 0;
+}
+
 static int bdx_ioctl_priv(struct net_device *ndev, struct ifreq *ifr, int cmd)
 {
 	struct bdx_priv *priv = ndev->priv;
@@ -646,6 +652,9 @@
 	switch (data[0]) {
 
 	case BDX_OP_READ:
+		error = bdx_range_check(priv, data[1]);
+		if (error < 0)
+			return error;
 		data[2] = READ_REG(priv, data[1]);
 		DBG("read_reg(0x%x)=0x%x (dec %d)\n", data[1], data[2],
 		    data[2]);
@@ -655,6 +664,11 @@
 		break;
 
 	case BDX_OP_WRITE:
+		if (!capable(CAP_NET_ADMIN))
+			return -EPERM;
+		error = bdx_range_check(priv, data[1]);
+		if (error < 0)
+			return error;
 		WRITE_REG(priv, data[1], data[2]);
 		DBG("write_reg(0x%x, 0x%x)\n", data[1], data[2]);
 		break;