[ Upstream commit 0db6f8befc32c68bb13d7ffbb2e563c79e913e13 ] It returned always NULL, thus it was never possible to get the filter. Example: $ ip link add foo type dummy $ ip link add bar type dummy $ tc qdisc add dev foo clsact $ tc filter add dev foo protocol all pref 1 ingress handle 1234 \ matchall action mirred ingress mirror dev bar Before the patch: $ tc filter get dev foo protocol all pref 1 ingress handle 1234 matchall Error: Specified filter handle not found. We have an error talking to the kernel After: $ tc filter get dev foo protocol all pref 1 ingress handle 1234 matchall filter ingress protocol all pref 1 matchall chain 0 handle 0x4d2 not_in_hw action order 1: mirred (Ingress Mirror to device bar) pipe index 1 ref 1 bind 1 CC: Yotam Gigi <yotamg@xxxxxxxxxxxx> CC: Jiri Pirko <jiri@xxxxxxxxxxxx> Fixes: fd62d9f5c575 ("net/sched: matchall: Fix configuration race") Signed-off-by: Nicolas Dichtel <nicolas.dichtel@xxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- net/sched/cls_matchall.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/net/sched/cls_matchall.c b/net/sched/cls_matchall.c index 0e408ee9dcec..5ba07cd11e31 100644 --- a/net/sched/cls_matchall.c +++ b/net/sched/cls_matchall.c @@ -125,6 +125,11 @@ static void mall_destroy(struct tcf_proto *tp, struct netlink_ext_ack *extack) static void *mall_get(struct tcf_proto *tp, u32 handle) { + struct cls_mall_head *head = rtnl_dereference(tp->root); + + if (head && head->handle == handle) + return head; + return NULL; } -- 2.19.1