[PATCH net 1/3] dpaa2-eth: Fix potential spectre issue

[Ioana Radulescu]

Smatch reports a potential spectre vulnerability in the dpaa2-eth
driver, where the value of rxnfc->fs.location (which is provided
from user-space) is used as index in an array.

Add a call to array_index_nospec() to sanitize the access.

Signed-off-by: Ioana Radulescu <ruxandra.radule...@nxp.com>
---
 drivers/net/ethernet/freescale/dpaa2/dpaa2-ethtool.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/net/ethernet/freescale/dpaa2/dpaa2-ethtool.c 
b/drivers/net/ethernet/freescale/dpaa2/dpaa2-ethtool.c
index 76bd8d2..7b182f4 100644
--- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-ethtool.c
+++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-ethtool.c
@@ -4,6 +4,7 @@
  */
 
 #include <linux/net_tstamp.h>
+#include <linux/nospec.h>
 
 #include "dpni.h"      /* DPNI_LINK_OPT_* */
 #include "dpaa2-eth.h"
@@ -648,6 +649,8 @@ static int dpaa2_eth_get_rxnfc(struct net_device *net_dev,
        case ETHTOOL_GRXCLSRULE:
                if (rxnfc->fs.location >= max_rules)
                        return -EINVAL;
+               rxnfc->fs.location = array_index_nospec(rxnfc->fs.location,
+                                                       max_rules);
                if (!priv->cls_rules[rxnfc->fs.location].in_use)
                        return -EINVAL;
                rxnfc->fs = priv->cls_rules[rxnfc->fs.location].fs;
-- 
2.7.4