diff options
| author | Jamal Hadi Salim <jhs@mojatatu.com> | 2017-01-15 10:14:06 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-02-04 09:47:09 +0100 |
| commit | b260a714a638cabb72f3d386ecb66ec04e06fcce (patch) | |
| tree | 0b5dcf53f2398f30cf9519f22ae163c65f2f93b7 /net/sched | |
| parent | 2d6b61ec9d3aed5091d6df4703a079d109bef3c1 (diff) | |
net sched actions: fix refcnt when GETing of action after bind
[ Upstream commit 0faa9cb5b3836a979864a6357e01d2046884ad52 ]
Demonstrating the issue:
.. add a drop action
$sudo $TC actions add action drop index 10
.. retrieve it
$ sudo $TC -s actions get action gact index 10
action order 1: gact action drop
random type none pass val 0
index 10 ref 2 bind 0 installed 29 sec used 29 sec
Action statistics:
Sent 0 bytes 0 pkt (dropped 0, overlimits 0 requeues 0)
backlog 0b 0p requeues 0
... bug 1 above: reference is two.
Reference is actually 1 but we forget to subtract 1.
... do a GET again and we see the same issue
try a few times and nothing changes
~$ sudo $TC -s actions get action gact index 10
action order 1: gact action drop
random type none pass val 0
index 10 ref 2 bind 0 installed 31 sec used 31 sec
Action statistics:
Sent 0 bytes 0 pkt (dropped 0, overlimits 0 requeues 0)
backlog 0b 0p requeues 0
... lets try to bind the action to a filter..
$ sudo $TC qdisc add dev lo ingress
$ sudo $TC filter add dev lo parent ffff: protocol ip prio 1 \
u32 match ip dst 127.0.0.1/32 flowid 1:1 action gact index 10
... and now a few GETs:
$ sudo $TC -s actions get action gact index 10
action order 1: gact action drop
random type none pass val 0
index 10 ref 3 bind 1 installed 204 sec used 204 sec
Action statistics:
Sent 0 bytes 0 pkt (dropped 0, overlimits 0 requeues 0)
backlog 0b 0p requeues 0
$ sudo $TC -s actions get action gact index 10
action order 1: gact action drop
random type none pass val 0
index 10 ref 4 bind 1 installed 206 sec used 206 sec
Action statistics:
Sent 0 bytes 0 pkt (dropped 0, overlimits 0 requeues 0)
backlog 0b 0p requeues 0
$ sudo $TC -s actions get action gact index 10
action order 1: gact action drop
random type none pass val 0
index 10 ref 5 bind 1 installed 235 sec used 235 sec
Action statistics:
Sent 0 bytes 0 pkt (dropped 0, overlimits 0 requeues 0)
backlog 0b 0p requeues 0
.... as can be observed the reference count keeps going up.
After the fix
$ sudo $TC actions add action drop index 10
$ sudo $TC -s actions get action gact index 10
action order 1: gact action drop
random type none pass val 0
index 10 ref 1 bind 0 installed 4 sec used 4 sec
Action statistics:
Sent 0 bytes 0 pkt (dropped 0, overlimits 0 requeues 0)
backlog 0b 0p requeues 0
$ sudo $TC -s actions get action gact index 10
action order 1: gact action drop
random type none pass val 0
index 10 ref 1 bind 0 installed 6 sec used 6 sec
Action statistics:
Sent 0 bytes 0 pkt (dropped 0, overlimits 0 requeues 0)
backlog 0b 0p requeues 0
$ sudo $TC qdisc add dev lo ingress
$ sudo $TC filter add dev lo parent ffff: protocol ip prio 1 \
u32 match ip dst 127.0.0.1/32 flowid 1:1 action gact index 10
$ sudo $TC -s actions get action gact index 10
action order 1: gact action drop
random type none pass val 0
index 10 ref 2 bind 1 installed 32 sec used 32 sec
Action statistics:
Sent 0 bytes 0 pkt (dropped 0, overlimits 0 requeues 0)
backlog 0b 0p requeues 0
$ sudo $TC -s actions get action gact index 10
action order 1: gact action drop
random type none pass val 0
index 10 ref 2 bind 1 installed 33 sec used 33 sec
Action statistics:
Sent 0 bytes 0 pkt (dropped 0, overlimits 0 requeues 0)
backlog 0b 0p requeues 0
Fixes: aecc5cefc389 ("net sched actions: fix GETing actions")
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net/sched')
| -rw-r--r-- | net/sched/act_api.c | 5 |
1 files changed, 2 insertions, 3 deletions
diff --git a/net/sched/act_api.c b/net/sched/act_api.c index f893d180da1c..c6c2a93cc2a2 100644 --- a/net/sched/act_api.c +++ b/net/sched/act_api.c @@ -903,8 +903,6 @@ tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n, goto err; } act->order = i; - if (event == RTM_GETACTION) - act->tcfa_refcnt++; list_add_tail(&act->list, &actions); } @@ -917,7 +915,8 @@ tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n, return ret; } err: - tcf_action_destroy(&actions, 0); + if (event != RTM_GETACTION) + tcf_action_destroy(&actions, 0); return ret; } |