diff options
| author | Kory Maincent <kory.maincent@bootlin.com> | 2024-12-20 11:37:40 +0300 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2024-12-23 21:38:46 +0300 |
| commit | 4c61d809cf608842112c77880f50810a564cd9cb (patch) | |
| tree | eb4b6caaaf125d8158cad6f46f9e58d5768a744c | |
| parent | 3f8f2e93cdfb96c77bf381590dd697867e89d9e7 (diff) | |
| download | linux-4c61d809cf608842112c77880f50810a564cd9cb.tar.xz | |
net: ethtool: Fix suspicious rcu_dereference usage
The __ethtool_get_ts_info function can be called with or without the
rtnl lock held. When the rtnl lock is not held, using rtnl_dereference()
triggers a warning due to the lack of lock context.
Add an rcu_read_lock() to ensure the lock is acquired and to maintain
synchronization.
Reported-by: syzbot+a344326c05c98ba19682@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/676147f8.050a0220.37aaf.0154.GAE@google.com/
Fixes: b9e3f7dc9ed9 ("net: ethtool: tsinfo: Enhance tsinfo to support several hwtstamp by net topology")
Signed-off-by: Kory Maincent <kory.maincent@bootlin.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20241220083741.175329-1-kory.maincent@bootlin.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| -rw-r--r-- | net/ethtool/common.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/net/ethtool/common.c b/net/ethtool/common.c index 02f941f667dd..2607aea1fbfb 100644 --- a/net/ethtool/common.c +++ b/net/ethtool/common.c @@ -870,7 +870,8 @@ int __ethtool_get_ts_info(struct net_device *dev, { struct hwtstamp_provider *hwprov; - hwprov = rtnl_dereference(dev->hwprov); + rcu_read_lock(); + hwprov = rcu_dereference(dev->hwprov); /* No provider specified, use default behavior */ if (!hwprov) { const struct ethtool_ops *ops = dev->ethtool_ops; @@ -887,9 +888,11 @@ int __ethtool_get_ts_info(struct net_device *dev, info->so_timestamping |= SOF_TIMESTAMPING_RX_SOFTWARE | SOF_TIMESTAMPING_SOFTWARE; + rcu_read_unlock(); return err; } + rcu_read_unlock(); return ethtool_get_ts_info_by_phc(dev, info, &hwprov->desc); } |