[PATCH 5.6 041/194] dpaa2-eth: prevent array underflow in update_cls_rule()

Greg Kroah-Hartman
2020-05-18T18:03:01Z

From: Dan Carpenter <dan.carpenter@oracle.com>

[ Upstream commit 6d32a5119811d2e9b5caa284181944c6f1f192ed ]

The "location" is controlled by the user via the ethtool_set_rxnfc()
function. This update_cls_rule() function checks for array overflows
but it doesn't check if the value is negative. I have changed the type
to unsigned to prevent array underflows.

Fixes: afb90dbb5f78 ("dpaa2-eth: Add ethtool support for flow classification")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/net/ethernet/freescale/dpaa2/dpaa2-ethtool.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-ethtool.c
+++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-ethtool.c
@@ -625,7 +625,7 @@ static int num_rules(struct dpaa2_eth_pr

static int update_cls_rule(struct net_device *net_dev,
struct ethtool_rx_flow_spec *new_fs,
- int location)
+ unsigned int location)
{
struct dpaa2_eth_priv *priv = netdev_priv(net_dev);
struct dpaa2_eth_cls_rule *rule;