linux/net/sched
Roman Mashak 37f1c63e3e net sched actions: do not overwrite status of action creation.
nla_memdup_cookie was overwriting err value, declared at function
scope and earlier initialized with result of ->init(). At success
nla_memdup_cookie() returns 0, and thus module refcnt decremented,
although the action was installed.

$ sudo tc actions add action pass index 1 cookie 1234
$ sudo tc actions ls action gact

        action order 0: gact action pass
         random type none pass val 0
         index 1 ref 1 bind 0
$
$ lsmod
Module                  Size  Used by
act_gact               16384  0
...
$
$ sudo rmmod act_gact
[   52.310283] ------------[ cut here ]------------
[   52.312551] WARNING: CPU: 1 PID: 455 at kernel/module.c:1113
module_put+0x99/0xa0
[   52.316278] Modules linked in: act_gact(-) crct10dif_pclmul crc32_pclmul
ghash_clmulni_intel psmouse pcbc evbug aesni_intel aes_x86_64 crypto_simd
serio_raw glue_helper pcspkr cryptd
[   52.322285] CPU: 1 PID: 455 Comm: rmmod Not tainted 4.10.0+ #11
[   52.324261] Call Trace:
[   52.325132]  dump_stack+0x63/0x87
[   52.326236]  __warn+0xd1/0xf0
[   52.326260]  warn_slowpath_null+0x1d/0x20
[   52.326260]  module_put+0x99/0xa0
[   52.326260]  tcf_hashinfo_destroy+0x7f/0x90
[   52.326260]  gact_exit_net+0x27/0x40 [act_gact]
[   52.326260]  ops_exit_list.isra.6+0x38/0x60
[   52.326260]  unregister_pernet_operations+0x90/0xe0
[   52.326260]  unregister_pernet_subsys+0x21/0x30
[   52.326260]  tcf_unregister_action+0x68/0xa0
[   52.326260]  gact_cleanup_module+0x17/0xa0f [act_gact]
[   52.326260]  SyS_delete_module+0x1ba/0x220
[   52.326260]  entry_SYSCALL_64_fastpath+0x1e/0xad
[   52.326260] RIP: 0033:0x7f527ffae367
[   52.326260] RSP: 002b:00007ffeb402a598 EFLAGS: 00000202 ORIG_RAX:
00000000000000b0
[   52.326260] RAX: ffffffffffffffda RBX: 0000559b069912a0 RCX: 00007f527ffae367
[   52.326260] RDX: 000000000000000a RSI: 0000000000000800 RDI: 0000559b06991308
[   52.326260] RBP: 0000000000000003 R08: 00007f5280264420 R09: 00007ffeb4029511
[   52.326260] R10: 000000000000087b R11: 0000000000000202 R12: 00007ffeb4029580
[   52.326260] R13: 0000000000000000 R14: 0000000000000000 R15: 0000559b069912a0
[   52.354856] ---[ end trace 90d89401542b0db6 ]---
$

With the fix:

$ sudo modprobe act_gact
$ lsmod
Module                  Size  Used by
act_gact               16384  0
...
$ sudo tc actions add action pass index 1 cookie 1234
$ sudo tc actions ls action gact

        action order 0: gact action pass
         random type none pass val 0
         index 1 ref 1 bind 0
$
$ lsmod
Module                  Size  Used by
act_gact               16384  1
...
$ sudo rmmod act_gact
rmmod: ERROR: Module act_gact is in use
$
$ sudo /home/mrv/bin/tc actions del action gact index 1
$ sudo rmmod act_gact
$ lsmod
Module                  Size  Used by
$

Fixes: 1045ba77a ("net sched actions: Add support for user cookies")
Signed-off-by: Roman Mashak <mrv@mojatatu.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-26 21:31:32 -05:00
..
act_api.c net sched actions: do not overwrite status of action creation. 2017-02-26 21:31:32 -05:00
act_bpf.c bpf: rework prog_digest into prog_tag 2017-01-16 14:03:31 -05:00
act_connmark.c netns: make struct pernet_operations::id unsigned int 2016-11-18 10:59:15 -05:00
act_csum.c net/sched: act_csum: compute crc32c on SCTP packets 2017-01-09 14:36:57 -05:00
act_gact.c netns: make struct pernet_operations::id unsigned int 2016-11-18 10:59:15 -05:00
act_ife.c net/sched: act_ife: Change to use ife module 2017-02-03 15:16:46 -05:00
act_ipt.c netns: make struct pernet_operations::id unsigned int 2016-11-18 10:59:15 -05:00
act_meta_mark.c
act_meta_skbprio.c
act_meta_skbtcindex.c net sched ife action: Introduce skb tcindex metadata encap decap 2016-09-19 21:55:28 -04:00
act_mirred.c net/sched: act_mirred: remove duplicated include from act_mirred.c 2017-02-07 11:42:34 -05:00
act_nat.c netns: make struct pernet_operations::id unsigned int 2016-11-18 10:59:15 -05:00
act_pedit.c net/act_pedit: Introduce 'add' operation 2017-02-10 13:18:33 -05:00
act_police.c net_sched: gen_estimator: complete rewrite of rate estimators 2016-12-05 15:21:59 -05:00
act_sample.c net/sched: act_psample: Remove unnecessary ASSERT_RTNL 2017-02-01 14:10:03 -05:00
act_simple.c netns: make struct pernet_operations::id unsigned int 2016-11-18 10:59:15 -05:00
act_skbedit.c netns: make struct pernet_operations::id unsigned int 2016-11-18 10:59:15 -05:00
act_skbmod.c netns: make struct pernet_operations::id unsigned int 2016-11-18 10:59:15 -05:00
act_tunnel_key.c net/sched: act_tunnel_key: Fix setting UDP dst port in metadata under IPv6 2016-12-23 11:59:56 -05:00
act_vlan.c netns: make struct pernet_operations::id unsigned int 2016-11-18 10:59:15 -05:00
cls_api.c sched: Fix accidental removal of errout goto 2017-02-14 11:44:14 -05:00
cls_basic.c net, sched: respect rcu grace period on cls destruction 2016-11-28 10:47:35 -05:00
cls_bpf.c net/sched: cls_bpf: Reflect HW offload status 2017-02-17 12:08:06 -05:00
cls_cgroup.c net, sched: respect rcu grace period on cls destruction 2016-11-28 10:47:35 -05:00
cls_flow.c skbuff: add and use skb_nfct helper 2017-02-02 14:31:53 +01:00
cls_flower.c net/sched: cls_flower: Reflect HW offload status 2017-02-17 12:08:05 -05:00
cls_fw.c net sched: stylistic cleanups 2016-09-19 22:04:14 -04:00
cls_matchall.c net/sched: cls_matchall: Reflect HW offloading status 2017-02-17 12:08:06 -05:00
cls_route.c net_sched: check NULL on error path in route4_change() 2016-09-23 06:51:49 -04:00
cls_rsvp6.c
cls_rsvp.c
cls_rsvp.h net, sched: respect rcu grace period on cls destruction 2016-11-28 10:47:35 -05:00
cls_tcindex.c net, sched: respect rcu grace period on cls destruction 2016-11-28 10:47:35 -05:00
cls_u32.c net/sched: cls_u32: Reflect HW offload status 2017-02-17 12:08:06 -05:00
em_canid.c
em_cmp.c
em_ipset.c netfilter: x_tables: move hook state into xt_action_param structure 2016-11-03 10:56:21 +01:00
em_meta.c net/sched: em_meta: Fix 'meta vlan' to correctly recognize zero VID frames 2016-10-23 17:31:25 -04:00
em_nbyte.c
em_text.c
em_u32.c
ematch.c
Kconfig net/sched: act_ife: Change to use ife module 2017-02-03 15:16:46 -05:00
Makefile net/sched: Introduce sample tc action 2017-01-24 13:44:28 -05:00
sch_api.c pkt_sched: Remove useless qdisc_stab_lock 2017-02-17 15:10:18 -05:00
sch_atm.c sched: move tcf_proto_destroy and tcf_destroy_chain helpers into cls_api 2017-02-10 11:38:08 -05:00
sch_blackhole.c net_sched: drop packets after root qdisc lock is released 2016-06-25 12:19:35 -04:00
sch_cbq.c sched: move tcf_proto_destroy and tcf_destroy_chain helpers into cls_api 2017-02-10 11:38:08 -05:00
sch_choke.c sched: move tcf_proto_destroy and tcf_destroy_chain helpers into cls_api 2017-02-10 11:38:08 -05:00
sch_codel.c sched: replace __skb_dequeue with __qdisc_dequeue_head 2016-09-19 01:47:18 -04:00
sch_drr.c net_sched: gen_estimator: complete rewrite of rate estimators 2016-12-05 15:21:59 -05:00
sch_dsmark.c sched: move tcf_proto_destroy and tcf_destroy_chain helpers into cls_api 2017-02-10 11:38:08 -05:00
sch_fifo.c sched: don't use skb queue helpers 2016-09-19 01:47:18 -04:00
sch_fq_codel.c sched: move tcf_proto_destroy and tcf_destroy_chain helpers into cls_api 2017-02-10 11:38:08 -05:00
sch_fq.c net_sched: sch_fq: use rb_entry() 2016-12-20 14:22:48 -05:00
sch_generic.c net: dev_weight: TX/RX orthogonality 2016-12-29 15:38:35 -05:00
sch_gred.c net_sched: drop packets after root qdisc lock is released 2016-06-25 12:19:35 -04:00
sch_hfsc.c net_sched: gen_estimator: complete rewrite of rate estimators 2016-12-05 15:21:59 -05:00
sch_hhf.c net_sched: fix error recovery at qdisc creation 2017-02-11 21:38:58 -05:00
sch_htb.c sched: move tcf_proto_destroy and tcf_destroy_chain helpers into cls_api 2017-02-10 11:38:08 -05:00
sch_ingress.c sched: move tcf_proto_destroy and tcf_destroy_chain helpers into cls_api 2017-02-10 11:38:08 -05:00
sch_mq.c net_sched: fix error recovery at qdisc creation 2017-02-11 21:38:58 -05:00
sch_mqprio.c net_sched: fix error recovery at qdisc creation 2017-02-11 21:38:58 -05:00
sch_multiq.c sched: move tcf_proto_destroy and tcf_destroy_chain helpers into cls_api 2017-02-10 11:38:08 -05:00
sch_netem.c net-tc: convert tc_from to tc_from_ingress and tc_redirected 2017-01-08 20:58:52 -05:00
sch_pie.c sched: replace __skb_dequeue with __qdisc_dequeue_head 2016-09-19 01:47:18 -04:00
sch_plug.c net_sched: drop packets after root qdisc lock is released 2016-06-25 12:19:35 -04:00
sch_prio.c sched: move tcf_proto_destroy and tcf_destroy_chain helpers into cls_api 2017-02-10 11:38:08 -05:00
sch_qfq.c net_sched: gen_estimator: complete rewrite of rate estimators 2016-12-05 15:21:59 -05:00
sch_red.c net_sched: drop packets after root qdisc lock is released 2016-06-25 12:19:35 -04:00
sch_sfb.c sched: move tcf_proto_destroy and tcf_destroy_chain helpers into cls_api 2017-02-10 11:38:08 -05:00
sch_sfq.c net_sched: fix error recovery at qdisc creation 2017-02-11 21:38:58 -05:00
sch_tbf.c net_sched: drop packets after root qdisc lock is released 2016-06-25 12:19:35 -04:00
sch_teql.c net: make ndo_get_stats64 a void function 2017-01-08 17:51:44 -05:00