From b493f881aaa70ac63a448267bd447ad1eb2b16a1 Mon Sep 17 00:00:00 2001 From: Li RongQing Date: Thu, 9 Jan 2025 19:10:57 +0800 Subject: [PATCH] net: ethtool: Use hwprov under rcu_read_lock hwprov should be protected by rcu_read_lock to prevent possible UAF Fixes: 4c61d809cf60 ("net: ethtool: Fix suspicious rcu_dereference usage") Signed-off-by: Li RongQing Acked-by: Kory Maincent diff with v1: move and use err varialbe, instead of define a new variable net/ethtool/common.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) Link: https://patch.msgid.link/20250109111057.4746-1-lirongqing@baidu.com Signed-off-by: Jakub Kicinski --- net/ethtool/common.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/net/ethtool/common.c b/net/ethtool/common.c index 2607aea1fbfb..2bd77c94f9f1 100644 --- a/net/ethtool/common.c +++ b/net/ethtool/common.c @@ -869,6 +869,7 @@ int __ethtool_get_ts_info(struct net_device *dev, struct kernel_ethtool_ts_info *info) { struct hwtstamp_provider *hwprov; + int err = 0; rcu_read_lock(); hwprov = rcu_dereference(dev->hwprov); @@ -876,7 +877,6 @@ int __ethtool_get_ts_info(struct net_device *dev, if (!hwprov) { const struct ethtool_ops *ops = dev->ethtool_ops; struct phy_device *phydev = dev->phydev; - int err = 0; ethtool_init_tsinfo(info); if (phy_is_default_hwtstamp(phydev) && @@ -892,8 +892,9 @@ int __ethtool_get_ts_info(struct net_device *dev, return err; } + err = ethtool_get_ts_info_by_phc(dev, info, &hwprov->desc); rcu_read_unlock(); - return ethtool_get_ts_info_by_phc(dev, info, &hwprov->desc); + return err; } bool net_support_hwtstamp_qualifier(struct net_device *dev, -- 2.25.1