diff options
| author | Yousef Alhouseen <alhouseenyousef@gmail.com> | 2026-06-28 02:28:04 +0200 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2026-06-29 18:47:23 -0700 |
| commit | 2e996ca81f9512c2d39d826a5146e5fe4ab28277 (patch) | |
| tree | 67a5a43842ec7c95dc60514665e5b5b6a725d44a /drivers/net/netdevsim | |
| parent | 9facb861dc6b9b9ea9793ef5032a9a826f7a4229 (diff) | |
netdevsim: remove ethtool debugfs files before freeing netdev
The ethtool debugfs files point directly into struct netdevsim, which is
allocated as net_device private data. Their containing port directory is
removed only after nsim_destroy() calls free_netdev().
An open simple-attribute file can consequently dereference the freed
private data before the directory is removed. KASAN observed this in
debugfs_u32_get() during network namespace teardown.
Track and remove the ethtool subtree before free_netdev() on both the
normal and registration-failure paths. debugfs removal drains active
file users before returning.
Fixes: ff1f7c17fb20 ("netdevsim: add pause frame stats")
Reported-by: syzbot+6c25f4750230faf70be9@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=6c25f4750230faf70be9
Cc: <stable+noautosel@kernel.org> # netdevsim is a test harness, it's never loaded on production systems
Signed-off-by: Yousef Alhouseen <alhouseenyousef@gmail.com>
Link: https://patch.msgid.link/20260628002804.24214-1-alhouseenyousef@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'drivers/net/netdevsim')
| -rw-r--r-- | drivers/net/netdevsim/ethtool.c | 6 | ||||
| -rw-r--r-- | drivers/net/netdevsim/netdev.c | 2 | ||||
| -rw-r--r-- | drivers/net/netdevsim/netdevsim.h | 2 |
3 files changed, 10 insertions, 0 deletions
diff --git a/drivers/net/netdevsim/ethtool.c b/drivers/net/netdevsim/ethtool.c index 9350ba48eb81..025ea79879f3 100644 --- a/drivers/net/netdevsim/ethtool.c +++ b/drivers/net/netdevsim/ethtool.c @@ -252,6 +252,7 @@ void nsim_ethtool_init(struct netdevsim *ns) ns->ethtool.channels = ns->nsim_bus_dev->num_queues; ethtool = debugfs_create_dir("ethtool", ns->nsim_dev_port->ddir); + ns->ethtool_ddir = ethtool; debugfs_create_u32("get_err", 0600, ethtool, &ns->ethtool.get_err); debugfs_create_u32("set_err", 0600, ethtool, &ns->ethtool.set_err); @@ -272,3 +273,8 @@ void nsim_ethtool_init(struct netdevsim *ns) debugfs_create_u32("tx_max_pending", 0600, dir, &ns->ethtool.ring.tx_max_pending); } + +void nsim_ethtool_fini(struct netdevsim *ns) +{ + debugfs_remove(ns->ethtool_ddir); +} diff --git a/drivers/net/netdevsim/netdev.c b/drivers/net/netdevsim/netdev.c index 27e5f109f933..4e9d7e10b527 100644 --- a/drivers/net/netdevsim/netdev.c +++ b/drivers/net/netdevsim/netdev.c @@ -1165,6 +1165,7 @@ struct netdevsim *nsim_create(struct nsim_dev *nsim_dev, return ns; err_free_netdev: + nsim_ethtool_fini(ns); free_netdev(dev); return ERR_PTR(err); } @@ -1178,6 +1179,7 @@ void nsim_destroy(struct netdevsim *ns) debugfs_remove(ns->vlan_dfs); debugfs_remove(ns->qr_dfs); debugfs_remove(ns->pp_dfs); + nsim_ethtool_fini(ns); if (ns->nb.notifier_call) unregister_netdevice_notifier_dev_net(ns->netdev, &ns->nb, diff --git a/drivers/net/netdevsim/netdevsim.h b/drivers/net/netdevsim/netdevsim.h index 4c9cc96dcec3..64f77f93d937 100644 --- a/drivers/net/netdevsim/netdevsim.h +++ b/drivers/net/netdevsim/netdevsim.h @@ -154,6 +154,7 @@ struct netdevsim { struct dentry *pp_dfs; struct dentry *qr_dfs; struct dentry *vlan_dfs; + struct dentry *ethtool_ddir; struct nsim_ethtool ethtool; struct netdevsim __rcu *peer; @@ -169,6 +170,7 @@ void nsim_destroy(struct netdevsim *ns); bool netdev_is_nsim(struct net_device *dev); void nsim_ethtool_init(struct netdevsim *ns); +void nsim_ethtool_fini(struct netdevsim *ns); void nsim_udp_tunnels_debugfs_create(struct nsim_dev *nsim_dev); int nsim_udp_tunnels_info_create(struct nsim_dev *nsim_dev, |