The 04/08/2021 14:16, Jakub Kicinski wrote:
> On Thu, 8 Apr 2021 07:47:18 +0000 Jianbo Liu wrote:
> > When device is removed, indirect block is unregisterd. As
> > bo->unlocked_driver_cb is not initialized, the following UBSAN is
> > triggered.
> >
> > UBSAN: invalid-load in net/sched/cls_api.c:1496:10
> > load of value 6 is not a valid value for type '_Bool'
> >
> > This patch fixes the warning by calling device's indr block bind
> > callback, and unlocked_driver_cb is assigned with correct value.
> >
> > Fixes: 0fdcf78d5973 ("net: use flow_indr_dev_setup_offload()")
> > Signed-off-by: Jianbo Liu <jian...@nvidia.com>
> > Reviewed-by: Roi Dayan <r...@nvidia.com>
>
> It's been a while since I looked at this code but I don't understand
> what you're doing here.
To fix the UBSAN warning in tcf_block_unbind. It's easily triggered when
netdev is removed before tunnel netdev.
>
> The init in tc_block_indr_cleanup() makes sense. What's the change to
> setup_cb achieving? Thanks.
But unlocked_driver_cb of flow_block_offload is not initialized in init.
Calling setup_cb is to get the correct value from driver.
>
> > diff --git a/include/net/flow_offload.h b/include/net/flow_offload.h
> > index dc5c1e69cd9f..8cdc60833890 100644
> > --- a/include/net/flow_offload.h
> > +++ b/include/net/flow_offload.h
> > @@ -459,6 +459,11 @@ typedef int flow_setup_cb_t(enum tc_setup_type type,
> > void *type_data,
> >
> > struct flow_block_cb;
> >
> > +typedef int flow_indr_block_bind_cb_t(struct net_device *dev, struct Qdisc
> > *sch, void *cb_priv,
> > + enum tc_setup_type type, void *type_data,
> > + void *data,
> > + void (*cleanup)(struct flow_block_cb
> > *block_cb));
> > +
> > struct flow_block_indr {
> > struct list_head list;
> > struct net_device *dev;
> > @@ -466,6 +471,7 @@ struct flow_block_indr {
> > enum flow_block_binder_type binder_type;
> > void *data;
> > void *cb_priv;
> > + flow_indr_block_bind_cb_t *setup_cb;
> > void (*cleanup)(struct flow_block_cb
> > *block_cb);
> > };
> >
> > @@ -562,11 +568,6 @@ static inline void flow_block_init(struct flow_block
> > *flow_block)
> > INIT_LIST_HEAD(&flow_block->cb_list);
> > }
> >
> > -typedef int flow_indr_block_bind_cb_t(struct net_device *dev, struct Qdisc
> > *sch, void *cb_priv,
> > - enum tc_setup_type type, void *type_data,
> > - void *data,
> > - void (*cleanup)(struct flow_block_cb
> > *block_cb));
> > -
> > int flow_indr_dev_register(flow_indr_block_bind_cb_t *cb, void *cb_priv);
> > void flow_indr_dev_unregister(flow_indr_block_bind_cb_t *cb, void *cb_priv,
> > void (*release)(void *cb_priv));
> > diff --git a/net/core/flow_offload.c b/net/core/flow_offload.c
> > index 715b67f6c62f..85a3d8530952 100644
> > --- a/net/core/flow_offload.c
> > +++ b/net/core/flow_offload.c
> > @@ -373,7 +373,8 @@ int flow_indr_dev_register(flow_indr_block_bind_cb_t
> > *cb, void *cb_priv)
> > }
> > EXPORT_SYMBOL(flow_indr_dev_register);
> >
> > -static void __flow_block_indr_cleanup(void (*release)(void *cb_priv),
> > +static void __flow_block_indr_cleanup(struct flow_indr_dev *indr_dev,
> > + void (*release)(void *cb_priv),
> > void *cb_priv,
> > struct list_head *cleanup_list)
> > {
> > @@ -381,8 +382,10 @@ static void __flow_block_indr_cleanup(void
> > (*release)(void *cb_priv),
> >
> > list_for_each_entry_safe(this, next, &flow_block_indr_list, indr.list) {
> > if (this->release == release &&
> > - this->indr.cb_priv == cb_priv)
> > + this->indr.cb_priv == cb_priv) {
> > + this->indr.setup_cb = indr_dev->cb;
> > list_move(&this->indr.list, cleanup_list);
> > + }
> > }
> > }
> >
> > @@ -390,10 +393,8 @@ static void flow_block_indr_notify(struct list_head
> > *cleanup_list)
> > {
> > struct flow_block_cb *this, *next;
> >
> > - list_for_each_entry_safe(this, next, cleanup_list, indr.list) {
> > - list_del(&this->indr.list);
> > + list_for_each_entry_safe(this, next, cleanup_list, indr.list)
> > this->indr.cleanup(this);
> > - }
> > }
> >
> > void flow_indr_dev_unregister(flow_indr_block_bind_cb_t *cb, void *cb_priv,
> > @@ -418,7 +419,7 @@ void flow_indr_dev_unregister(flow_indr_block_bind_cb_t
> > *cb, void *cb_priv,
> > return;
> > }
> >
> > - __flow_block_indr_cleanup(release, cb_priv, &cleanup_list);
> > + __flow_block_indr_cleanup(this, release, cb_priv, &cleanup_list);
> > mutex_unlock(&flow_indr_block_lock);
> >
> > flow_block_indr_notify(&cleanup_list);
> > diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
> > index d3db70865d66..b213206da728 100644
> > --- a/net/sched/cls_api.c
> > +++ b/net/sched/cls_api.c
> > @@ -646,7 +646,7 @@ static void tc_block_indr_cleanup(struct flow_block_cb
> > *block_cb)
> > struct net_device *dev = block_cb->indr.dev;
> > struct Qdisc *sch = block_cb->indr.sch;
> > struct netlink_ext_ack extack = {};
> > - struct flow_block_offload bo;
> > + struct flow_block_offload bo = {};
> >
> > tcf_block_offload_init(&bo, dev, sch, FLOW_BLOCK_UNBIND,
> > block_cb->indr.binder_type,
> > @@ -654,8 +654,13 @@ static void tc_block_indr_cleanup(struct flow_block_cb
> > *block_cb)
> > &extack);
> > rtnl_lock();
> > down_write(&block->cb_lock);
> > - list_del(&block_cb->driver_list);
> > - list_move(&block_cb->list, &bo.cb_list);
> > + if (!block_cb->indr.setup_cb ||
> > + block_cb->indr.setup_cb(dev, sch, block_cb->indr.cb_priv,
> > + TC_SETUP_BLOCK, &bo, block, NULL)) {
> > + list_del(&block_cb->indr.list);
> > + list_del(&block_cb->driver_list);
> > + list_move(&block_cb->list, &bo.cb_list);
> > + }
> > tcf_block_unbind(block, &bo);
> > up_write(&block->cb_lock);
> > rtnl_unlock();
>
--
