| Message ID | 20200805071911.64101-1-xiangxia.m.yue@gmail.com |
|---|---|
| State | Accepted |
| Delegated to: | David Miller |
| Headers | show |
| Series | net: openvswitch: silence suspicious RCU usage warning | expand |
On Wed, 2020-08-05 at 15:19 +0800, xiangxia.m.yue@gmail.com wrote: > From: Tonghao Zhang <xiangxia.m.yue@gmail.com> > > ovs_flow_tbl_destroy always is called from RCU callback > or error path. It is no need to check if rcu_read_lock > or lockdep_ovsl_is_held was held. > > ovs_dp_cmd_fill_info always is called with ovs_mutex, > So use the rcu_dereference_ovsl instead of rcu_dereference > in ovs_flow_tbl_masks_cache_size. > > Fixes: 9bf24f594c6a ("net: openvswitch: make masks cache size configurable") > Cc: Eelco Chaudron <echaudro@redhat.com> > Reported-by: syzbot+c0eb9e7cdde04e4eb4be@syzkaller.appspotmail.com > Reported-by: syzbot+f612c02823acb02ff9bc@syzkaller.appspotmail.com > Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com> Acked-by: Paolo Abeni <pabeni@redhat.com>
From: xiangxia.m.yue@gmail.com Date: Wed, 5 Aug 2020 15:19:11 +0800 > From: Tonghao Zhang <xiangxia.m.yue@gmail.com> > > ovs_flow_tbl_destroy always is called from RCU callback > or error path. It is no need to check if rcu_read_lock > or lockdep_ovsl_is_held was held. > > ovs_dp_cmd_fill_info always is called with ovs_mutex, > So use the rcu_dereference_ovsl instead of rcu_dereference > in ovs_flow_tbl_masks_cache_size. > > Fixes: 9bf24f594c6a ("net: openvswitch: make masks cache size configurable") > Cc: Eelco Chaudron <echaudro@redhat.com> > Reported-by: syzbot+c0eb9e7cdde04e4eb4be@syzkaller.appspotmail.com > Reported-by: syzbot+f612c02823acb02ff9bc@syzkaller.appspotmail.com > Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com> Applied, thank you.
On 5 Aug 2020, at 9:19, xiangxia.m.yue@gmail.com wrote: > From: Tonghao Zhang <xiangxia.m.yue@gmail.com> > > ovs_flow_tbl_destroy always is called from RCU callback > or error path. It is no need to check if rcu_read_lock > or lockdep_ovsl_is_held was held. > > ovs_dp_cmd_fill_info always is called with ovs_mutex, > So use the rcu_dereference_ovsl instead of rcu_dereference > in ovs_flow_tbl_masks_cache_size. > > Fixes: 9bf24f594c6a ("net: openvswitch: make masks cache size > configurable") > Cc: Eelco Chaudron <echaudro@redhat.com> > Reported-by: syzbot+c0eb9e7cdde04e4eb4be@syzkaller.appspotmail.com > Reported-by: syzbot+f612c02823acb02ff9bc@syzkaller.appspotmail.com > Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com> Thanks for fixing this, I was (am) on PTO so did not notice it earlier! Cheers, Eelco
diff --git a/net/openvswitch/flow_table.c b/net/openvswitch/flow_table.c index 6527d84c3ea6..8c12675cbb67 100644 --- a/net/openvswitch/flow_table.c +++ b/net/openvswitch/flow_table.c @@ -518,8 +518,8 @@ void ovs_flow_tbl_destroy(struct flow_table *table) { struct table_instance *ti = rcu_dereference_raw(table->ti); struct table_instance *ufid_ti = rcu_dereference_raw(table->ufid_ti); - struct mask_cache *mc = rcu_dereference(table->mask_cache); - struct mask_array *ma = rcu_dereference_ovsl(table->mask_array); + struct mask_cache *mc = rcu_dereference_raw(table->mask_cache); + struct mask_array *ma = rcu_dereference_raw(table->mask_array); call_rcu(&mc->rcu, mask_cache_rcu_cb); call_rcu(&ma->rcu, mask_array_rcu_cb); @@ -937,7 +937,7 @@ int ovs_flow_tbl_num_masks(const struct flow_table *table) u32 ovs_flow_tbl_masks_cache_size(const struct flow_table *table) { - struct mask_cache *mc = rcu_dereference(table->mask_cache); + struct mask_cache *mc = rcu_dereference_ovsl(table->mask_cache); return READ_ONCE(mc->cache_size); }