This is a note to let you know that I've just added the patch titled net: ethernet: mtk_eth_soc: fix possible NULL pointer dereference in mtk_hwlro_get_fdir_all() to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: net-ethernet-mtk_eth_soc-fix-possible-null-pointer-d.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit b4c142dc0e8af7442ac10d69159be8ce763019be Author: Hangyu Hua <hbh25y@xxxxxxxxx> Date: Fri Sep 8 14:19:50 2023 +0800 net: ethernet: mtk_eth_soc: fix possible NULL pointer dereference in mtk_hwlro_get_fdir_all() [ Upstream commit e4c79810755f66c9a933ca810da2724133b1165a ] rule_locs is allocated in ethtool_get_rxnfc and the size is determined by rule_cnt from user space. So rule_cnt needs to be check before using rule_locs to avoid NULL pointer dereference. Fixes: 7aab747e5563 ("net: ethernet: mediatek: add ethtool functions to configure RX flows of HW LRO") Signed-off-by: Hangyu Hua <hbh25y@xxxxxxxxx> Reviewed-by: Simon Horman <horms@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c index f9139150a8a26..7b9f5eba78dcc 100644 --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c @@ -2008,6 +2008,9 @@ static int mtk_hwlro_get_fdir_all(struct net_device *dev, int i; for (i = 0; i < MTK_MAX_LRO_IP_CNT; i++) { + if (cnt == cmd->rule_cnt) + return -EMSGSIZE; + if (mac->hwlro_ip[i]) { rule_locs[cnt] = i; cnt++;