| Message ID | 20150203141059.GA25454@zenon.in.qult.net |
|---|---|
| State | RFC, archived |
| Delegated to: | David Miller |
| Headers | show |
Hi again, After some playing around, I found that my quick-and-dirty fix didn't actually do the job. I eventually traced the problem to come from the fact that tcf_exts_dump_stats() just assumed that the list of actions in exts->actions contains at least one element and accessed it using tcf_exts_first_act(). This is clearly not true in the case of filters with no associated action in particular, as in the case of my "basic" filter. Simply ensuring that the list is not empty beforehand is enough to fix the problem, just as is also done above in tcf_exts_dump(). Ignacy Gawędzki (1): cls_api.c: Fix dumping of non-existing actions' stats. net/sched/cls_api.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/net/sched/act_api.c b/net/sched/act_api.c index 3d43e49..6dd46be 100644 --- a/net/sched/act_api.c +++ b/net/sched/act_api.c @@ -602,7 +602,7 @@ int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *a, struct tcf_common *p = a->priv; if (p == NULL) - goto errout; + return 0; /* compat_mode being true specifies a call that is supposed
Hi everyone, I have a problem with tc filter and very simple "basic" filters with no associated action. The thing is I have an HTB qdisc with handle 1: with a single class 1:1 attached to it. When I add a basic filter that does nothing, tc filter add dev eth0 prio 1 handle 1 parent 1: basic classid 1:1 it doesn't completely appear when I type tc filter show dev eth0 When debugging basic_dump() in net/sched/cls_basic.c, I noticed that tcf_exts_dump_stats() returns -1, which triggers a jump to nla_put_failure which ends up removing all the added attributes so far. When looking at tcf_action_copy_stats() in net/sched/act_api.c, which is ultimately called by tcf_exts_dump_stats(), I see that the returned error is triggered by a->priv being NULL. Although I confess I didn't make the effort of understanding all the workings of a->priv in this context, it seems to me that if that is NULL, this is probably not a good reason to return an error. I made the change below and so far it works for me. Can anyone take a critical look at this? Thanks. Ignacy * to add additional backward compatibility statistic TLVs.