[PATCH 4.14 158/218] net: ethernet: mtk_eth_soc: out of bounds read in mtk_hwlro_get_fdir_entry()

Greg Kroah-Hartman
2022-06-13T11:05:17Z

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

[ Upstream commit e7e7104e2d5ddf3806a28695670f21bef471f1e1 ]

The "fsp->location" variable comes from user via ethtool_get_rxnfc().
Check that it is valid to prevent an out of bounds read.

Fixes: 7aab747e5563 ("net: ethernet: mediatek: add ethtool functions to configure RX flows of HW LRO")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/ethernet/mediatek/mtk_eth_soc.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
index dbd16dd5aa04..ade72b46e93c 100644
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
@@ -1579,6 +1579,9 @@ static int mtk_hwlro_get_fdir_entry(struct net_device *dev,
struct ethtool_rx_flow_spec *fsp =
(struct ethtool_rx_flow_spec *)&cmd->fs;

+ if (fsp->location >= ARRAY_SIZE(mac->hwlro_ip))
+ return -EINVAL;
+
/* only tcp dst ipv4 is meaningful, others are meaningless */
fsp->flow_type = TCP_V4_FLOW;
fsp->h_u.tcp_ip4_spec.ip4dst = ntohl(mac->hwlro_ip[fsp->location]);
--
2.35.1