On 01/22/2017 04:51 AM, Jamal Hadi Salim wrote: > From: Jamal Hadi Salim <j...@mojatatu.com> > > Introduce optional 128-bit action cookie. > Like all other cookie schemes in the networking world (eg in protocols > like http or existing kernel fib protocol field, etc) the idea is to save > user state that when retrieved serves as a correlator. The kernel > _should not_ intepret it. The user can store whatever they wish in the > 128 bits. > > Sample exercise(showing variable length use of cookie) > > .. create an accept action with cookie a1b2c3d4 > sudo $TC actions add action ok index 1 cookie a1b2c3d4 > > .. dump all gact actions.. > sudo $TC -s actions ls action gact > > action order 0: gact action pass > random type none pass val 0 > index 1 ref 1 bind 0 installed 5 sec used 5 sec > Action statistics: > Sent 0 bytes 0 pkt (dropped 0, overlimits 0 requeues 0) > backlog 0b 0p requeues 0 > cookie a1b2c3d4 > > .. bind the accept action to a filter.. > 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 1 > > ... send some traffic.. > $ ping 127.0.0.1 -c 3 > PING 127.0.0.1 (127.0.0.1) 56(84) bytes of data. > 64 bytes from 127.0.0.1: icmp_seq=1 ttl=64 time=0.020 ms > 64 bytes from 127.0.0.1: icmp_seq=2 ttl=64 time=0.027 ms > 64 bytes from 127.0.0.1: icmp_seq=3 ttl=64 time=0.038 ms > > --- 127.0.0.1 ping statistics --- > 3 packets transmitted, 3 received, 0% packet loss, time 2109ms > rtt min/avg/max/mdev = 0.020/0.028/0.038/0.008 ms 1 > > ... show some stats > $ sudo $TC -s actions get action gact index 1 > > action order 1: gact action pass > random type none pass val 0 > index 1 ref 2 bind 1 installed 204 sec used 5 sec > Action statistics: > Sent 12168 bytes 164 pkt (dropped 0, overlimits 0 requeues 0) > backlog 0b 0p requeues 0 > cookie a1b2c3d4 > > .. try longer cookie... > $ sudo $TC actions replace action ok index 1 cookie 1234567890abcdef > .. dump.. > $ sudo $TC -s actions ls action gact > > action order 1: gact action pass > random type none pass val 0 > index 1 ref 2 bind 1 installed 204 sec used 5 sec > Action statistics: > Sent 12168 bytes 164 pkt (dropped 0, overlimits 0 requeues 0) > backlog 0b 0p requeues 0 > cookie 1234567890abcdef > > Signed-off-by: Jamal Hadi Salim <j...@mojatatu.com>
> + a->act_cookie->data = nla_memdup(tb[TCA_ACT_COOKIE], > + GFP_KERNEL); > + if (!a->act_cookie->data) { > + err = -ENOMEM; > + tcf_hash_release(a, bind); > + goto err_mod; > + } Are not you leaking a->act_cookie here in case nla_memdup() fails here? -- Florian