On Tue 15 May 2018 at 11:57, Jiri Pirko <jiri@xxxxxxxxxxx> wrote: > Tue, May 15, 2018 at 01:41:45PM CEST, vladbu@xxxxxxxxxxxx wrote: >> >>On Tue 15 May 2018 at 11:39, Jiri Pirko <jiri@xxxxxxxxxxx> wrote: >>> Tue, May 15, 2018 at 01:32:51PM CEST, vladbu@xxxxxxxxxxxx wrote: >>>> >>>>On Tue 15 May 2018 at 11:24, Jiri Pirko <jiri@xxxxxxxxxxx> wrote: >>>>> Mon, May 14, 2018 at 04:27:08PM CEST, vladbu@xxxxxxxxxxxx wrote: >>>>>>Change action API to assume that action init function always takes >>>>>>reference to action, even when overwriting existing action. This is >>>>>>necessary because action API continues to use action pointer after init >>>>>>function is done. At this point action becomes accessible for concurrent >>>>>>modifications so user must always hold reference to it. >>>>>> >>>>>>Implement helper put list function to atomically release list of actions >>>>>>after action API init code is done using them. >>>>>> >>>>>>Signed-off-by: Vlad Buslov <vladbu@xxxxxxxxxxxx> >>>>>>--- >>>>>> net/sched/act_api.c | 38 +++++++++++++++++--------------------- >>>>>> 1 file changed, 17 insertions(+), 21 deletions(-) >>>>>> >>>>> >>>>> [...] >>>>> >>>>> >>>>>>@@ -1196,8 +1190,7 @@ tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n, >>>>>> return ret; >>>>>> } >>>>>> err: >>>>>>- if (event != RTM_GETACTION) >>>>> >>>>> Howcome you do this for RTM_GETACTION now too? Where is the related >>>>> "get"? >>>> >>>>In patch 5. There is always a possibility of concurrent delete without >>>>rtnl lock so all usages of action pointers were converted to hold >>>>reference to action. >>> >>> So that means that if you run kernel in between, with patch 5 but >>> without patch 7 and you do RTM_GETACTION, you leak a reference, right? >> >>Right. > > That is an issue. You need to make sure that the code is without bugs > like this after every applied patch. You need to make sure the code is > bisectable. Got it. Will fix in V2. > > Thanks. -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
