From a7df4870d79b00742da6cc93ca2f336a71db77f7 Mon Sep 17 00:00:00 2001 From: Cong Wang Date: Thu, 30 Apr 2020 20:53:49 -0700 Subject: net_sched: fix tcm_parent in tc filter dump When we tell kernel to dump filters from root (ffff:ffff), those filters on ingress (ffff:0000) are matched, but their true parents must be dumped as they are. However, kernel dumps just whatever we tell it, that is either ffff:ffff or ffff:0000: $ nl-cls-list --dev=dummy0 --parent=root cls basic dev dummy0 id none parent root prio 49152 protocol ip match-all cls basic dev dummy0 id :1 parent root prio 49152 protocol ip match-all $ nl-cls-list --dev=dummy0 --parent=ffff: cls basic dev dummy0 id none parent ffff: prio 49152 protocol ip match-all cls basic dev dummy0 id :1 parent ffff: prio 49152 protocol ip match-all This is confusing and misleading, more importantly this is a regression since 4.15, so the old behavior must be restored. And, when tc filters are installed on a tc class, the parent should be the classid, rather than the qdisc handle. Commit edf6711c9840 ("net: sched: remove classid and q fields from tcf_proto") removed the classid we save for filters, we can just restore this classid in tcf_block. Steps to reproduce this: ip li set dev dummy0 up tc qd add dev dummy0 ingress tc filter add dev dummy0 parent ffff: protocol arp basic action pass tc filter show dev dummy0 root Before this patch: filter protocol arp pref 49152 basic filter protocol arp pref 49152 basic handle 0x1 action order 1: gact action pass random type none pass val 0 index 1 ref 1 bind 1 After this patch: filter parent ffff: protocol arp pref 49152 basic filter parent ffff: protocol arp pref 49152 basic handle 0x1 action order 1: gact action pass random type none pass val 0 index 1 ref 1 bind 1 Fixes: a10fa20101ae ("net: sched: propagate q and parent from caller down to tcf_fill_node") Fixes: edf6711c9840 ("net: sched: remove classid and q fields from tcf_proto") Cc: Jamal Hadi Salim Cc: Jiri Pirko Signed-off-by: Cong Wang Acked-by: Jamal Hadi Salim Signed-off-by: David S. Miller --- include/net/sch_generic.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/net/sch_generic.h') diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h index 25d2ec4c8f00..8428aa614265 100644 --- a/include/net/sch_generic.h +++ b/include/net/sch_generic.h @@ -407,6 +407,7 @@ struct tcf_block { struct mutex lock; struct list_head chain_list; u32 index; /* block index for shared blocks */ + u32 classid; /* which class this block belongs to */ refcount_t refcnt; struct net *net; struct Qdisc *q; -- cgit v1.2.3-59-g8ed1b