| Message ID | 20250320165103.3926946-1-sdf@fomichev.me (mailing list archive) |
|---|---|
| State | New |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [net-next,v2] net: hold netdev reference during qdisc_create request_module | expand |
diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c index aef39f6dc6a8..85ddb811780c 100644 --- a/net/sched/sch_api.c +++ b/net/sched/sch_api.c @@ -1280,11 +1280,13 @@ static struct Qdisc *qdisc_create(struct net_device *dev, * We replay the request because the device may * go away in the mean time. */ + dev_hold(dev); netdev_unlock_ops(dev); rtnl_unlock(); request_module(NET_SCH_ALIAS_PREFIX "%s", name); rtnl_lock(); netdev_lock_ops(dev); + dev_put(dev); ops = qdisc_lookup_ops(kind); if (ops != NULL) { /* We will try again qdisc_lookup_ops,
Eric reports that by the time we call netdev_lock_ops after rtnl_unlock/rtnl_lock, the dev might point to an invalid device. Add extra dev_hold/dev_put to make sure the device pointer is still valid after rtnl_unlock. Fixes: a0527ee2df3f ("net: hold netdev instance lock during qdisc ndo_setup_tc") Reported-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/netdev/20250305163732.2766420-1-sdf@fomichev.me/T/#me8dfd778ea4c4463acab55644e3f9836bc608771 Signed-off-by: Stanislav Fomichev <sdf@fomichev.me> --- net/sched/sch_api.c | 2 ++ 1 file changed, 2 insertions(+)