linux/net/sched
Roman Mashak af5d01842f net sched actions: fix invalid pointer dereferencing if skbedit flags missing
When application fails to pass flags in netlink TLV for a new skbedit action,
the kernel results in the following oops:

[    8.307732] BUG: unable to handle kernel paging request at 0000000000021130
[    8.309167] PGD 80000000193d1067 P4D 80000000193d1067 PUD 180e0067 PMD 0
[    8.310595] Oops: 0000 [#1] SMP PTI
[    8.311334] Modules linked in: kvm_intel kvm irqbypass crct10dif_pclmul crc32_pclmul ghash_clmulni_intel pcbc aesni_intel aes_x86_64 crypto_simd cryptd glue_helper serio_raw
[    8.314190] CPU: 1 PID: 397 Comm: tc Not tainted 4.17.0-rc3+ #357
[    8.315252] RIP: 0010:__tcf_idr_release+0x33/0x140
[    8.316203] RSP: 0018:ffffa0718038f840 EFLAGS: 00010246
[    8.317123] RAX: 0000000000000001 RBX: 0000000000021100 RCX: 0000000000000000
[    8.319831] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000021100
[    8.321181] RBP: 0000000000000000 R08: 000000000004adf8 R09: 0000000000000122
[    8.322645] R10: 0000000000000000 R11: ffffffff9e5b01ed R12: 0000000000000000
[    8.324157] R13: ffffffff9e0d3cc0 R14: 0000000000000000 R15: 0000000000000000
[    8.325590] FS:  00007f591292e700(0000) GS:ffff8fcf5bc40000(0000) knlGS:0000000000000000
[    8.327001] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    8.327987] CR2: 0000000000021130 CR3: 00000000180e6004 CR4: 00000000001606a0
[    8.329289] Call Trace:
[    8.329735]  tcf_skbedit_init+0xa7/0xb0
[    8.330423]  tcf_action_init_1+0x362/0x410
[    8.331139]  ? try_to_wake_up+0x44/0x430
[    8.331817]  tcf_action_init+0x103/0x190
[    8.332511]  tc_ctl_action+0x11a/0x220
[    8.333174]  rtnetlink_rcv_msg+0x23d/0x2e0
[    8.333902]  ? _cond_resched+0x16/0x40
[    8.334569]  ? __kmalloc_node_track_caller+0x5b/0x2c0
[    8.335440]  ? rtnl_calcit.isra.31+0xf0/0xf0
[    8.336178]  netlink_rcv_skb+0xdb/0x110
[    8.336855]  netlink_unicast+0x167/0x220
[    8.337550]  netlink_sendmsg+0x2a7/0x390
[    8.338258]  sock_sendmsg+0x30/0x40
[    8.338865]  ___sys_sendmsg+0x2c5/0x2e0
[    8.339531]  ? pagecache_get_page+0x27/0x210
[    8.340271]  ? filemap_fault+0xa2/0x630
[    8.340943]  ? page_add_file_rmap+0x108/0x200
[    8.341732]  ? alloc_set_pte+0x2aa/0x530
[    8.342573]  ? finish_fault+0x4e/0x70
[    8.343332]  ? __handle_mm_fault+0xbc1/0x10d0
[    8.344337]  ? __sys_sendmsg+0x53/0x80
[    8.345040]  __sys_sendmsg+0x53/0x80
[    8.345678]  do_syscall_64+0x4f/0x100
[    8.346339]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[    8.347206] RIP: 0033:0x7f591191da67
[    8.347831] RSP: 002b:00007fff745abd48 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[    8.349179] RAX: ffffffffffffffda RBX: 00007fff745abe70 RCX: 00007f591191da67
[    8.350431] RDX: 0000000000000000 RSI: 00007fff745abdc0 RDI: 0000000000000003
[    8.351659] RBP: 000000005af35251 R08: 0000000000000001 R09: 0000000000000000
[    8.352922] R10: 00000000000005f1 R11: 0000000000000246 R12: 0000000000000000
[    8.354183] R13: 00007fff745afed0 R14: 0000000000000001 R15: 00000000006767c0
[    8.355400] Code: 41 89 d4 53 89 f5 48 89 fb e8 aa 20 fd ff 85 c0 0f 84 ed 00
00 00 48 85 db 0f 84 cf 00 00 00 40 84 ed 0f 85 cd 00 00 00 45 84 e4 <8b> 53 30
74 0d 85 d2 b8 ff ff ff ff 0f 8f b3 00 00 00 8b 43 2c
[    8.358699] RIP: __tcf_idr_release+0x33/0x140 RSP: ffffa0718038f840
[    8.359770] CR2: 0000000000021130
[    8.360438] ---[ end trace 60c66be45dfc14f0 ]---

The caller calls action's ->init() and passes pointer to "struct tc_action *a",
which later may be initialized to point at the existing action, otherwise
"struct tc_action *a" is still invalid, and therefore dereferencing it is an
error as happens in tcf_idr_release, where refcnt is decremented.

So in case of missing flags tcf_idr_release must be called only for
existing actions.

v2:
    - prepare patch for net tree

Fixes: 5e1567aeb7 ("net sched: skbedit action fix late binding")
Signed-off-by: Roman Mashak <mrv@mojatatu.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-11 15:52:43 -04:00
..
act_api.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-04-01 19:49:34 -04:00
act_bpf.c net/sched: fix NULL dereference in the error path of tcf_bpf_init() 2018-04-05 22:26:06 -04:00
act_connmark.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
act_csum.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
act_gact.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
act_ife.c net: sched: ife: handle malformed tlv length 2018-04-22 21:12:00 -04:00
act_ipt.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
act_meta_mark.c net: remove duplicate includes 2017-12-13 13:18:46 -05:00
act_meta_skbprio.c net sched actions: change IFE modules alias names 2017-10-12 22:13:20 -07:00
act_meta_skbtcindex.c net: remove duplicate includes 2017-12-13 13:18:46 -05:00
act_mirred.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
act_nat.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
act_pedit.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
act_police.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
act_sample.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
act_simple.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
act_skbedit.c net sched actions: fix invalid pointer dereferencing if skbedit flags missing 2018-05-11 15:52:43 -04:00
act_skbmod.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
act_tunnel_key.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
act_vlan.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
cls_api.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
cls_basic.c cls_basic: Convert to use idr_alloc_u32 2018-02-06 16:41:26 -05:00
cls_bpf.c cls_bpf: Convert to use idr_alloc_u32 2018-02-06 16:41:26 -05:00
cls_cgroup.c net: sched: propagate extack to cls->destroy callbacks 2018-01-24 16:01:09 -05:00
cls_flow.c net: sched: propagate extack to cls->destroy callbacks 2018-01-24 16:01:09 -05:00
cls_flower.c net/sched: cls_flower: Add support to handle first frag as match field 2018-03-08 12:16:29 -05:00
cls_fw.c net: sched: propagate extack to cls->destroy callbacks 2018-01-24 16:01:09 -05:00
cls_matchall.c cls_matchall: propagate extack to delete callback 2018-01-24 16:01:10 -05:00
cls_route.c net: sched: propagate extack to cls->destroy callbacks 2018-01-24 16:01:09 -05:00
cls_rsvp6.c
cls_rsvp.c
cls_rsvp.h net: sched: propagate extack to cls->destroy callbacks 2018-01-24 16:01:09 -05:00
cls_tcindex.c net: sched: propagate extack to cls->destroy callbacks 2018-01-24 16:01:09 -05:00
cls_u32.c net_sched: fix a missing idr_remove() in u32_delete_key() 2018-04-07 12:36:45 -04:00
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_ipt.c net: sched: add em_ipt ematch for calling xtables matches 2018-02-21 13:15:33 -05:00
em_meta.c net: convert sock.sk_refcnt from atomic_t to refcount_t 2017-07-01 07:39:08 -07:00
em_nbyte.c net: sched: em_nbyte: don't add the data offset twice 2018-01-24 14:52:40 -05:00
em_text.c
em_u32.c
ematch.c net: sched: ematch: obtain net pointer from blocks 2017-10-16 21:00:40 +01:00
Kconfig net: sched: add em_ipt ematch for calling xtables matches 2018-02-21 13:15:33 -05:00
Makefile net: sched: add em_ipt ematch for calling xtables matches 2018-02-21 13:15:33 -05:00
sch_api.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
sch_atm.c net: sch: api: add extack support in qdisc_create_dflt 2017-12-21 12:32:51 -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 net: sch: sch_cbq: add extack support 2017-12-21 12:32:51 -05:00
sch_cbs.c net: sch: sch_cbs: add extack support 2017-12-21 12:32:51 -05:00
sch_choke.c net: sched: sch: add extack for change qdisc ops 2017-12-21 12:32:50 -05:00
sch_codel.c net: sched: sch: add extack for change qdisc ops 2017-12-21 12:32:50 -05:00
sch_drr.c net: sch: sch_drr: add extack support 2017-12-21 12:32:51 -05:00
sch_dsmark.c net: sch: api: add extack support in qdisc_create_dflt 2017-12-21 12:32:51 -05:00
sch_fifo.c net: sch: api: add extack support in qdisc_create_dflt 2017-12-21 12:32:51 -05:00
sch_fq_codel.c net: sch: api: add extack support in tcf_block_get 2017-12-21 12:32:51 -05:00
sch_fq.c net_sched: fq: take care of throttled flows before reuse 2018-05-02 16:37:38 -04:00
sch_generic.c net: sched, fix OOO packets with pfifo_fast 2018-03-26 12:36:23 -04:00
sch_gred.c net: sched: sch: add extack for change qdisc ops 2017-12-21 12:32:50 -05:00
sch_hfsc.c net: sch: api: add extack support in qdisc_create_dflt 2017-12-21 12:32:51 -05:00
sch_hhf.c net: sched: sch: add extack for change qdisc ops 2017-12-21 12:32:50 -05:00
sch_htb.c net: sched: do not emit messages while holding spinlock 2018-04-01 20:53:50 -04:00
sch_ingress.c net: sched: allow ingress and clsact qdiscs to share filter blocks 2018-01-17 14:53:57 -05:00
sch_mq.c net: sch: api: add extack support in qdisc_create_dflt 2017-12-21 12:32:51 -05:00
sch_mqprio.c net: sch: api: add extack support in qdisc_create_dflt 2017-12-21 12:32:51 -05:00
sch_multiq.c net: sch: api: add extack support in qdisc_create_dflt 2017-12-21 12:32:51 -05:00
sch_netem.c sch_netem: fix skb leak in netem_enqueue() 2018-03-07 11:18:14 -05:00
sch_pie.c net: sched: sch: add extack for change qdisc ops 2017-12-21 12:32:50 -05:00
sch_plug.c net: sched: sch: add extack for change qdisc ops 2017-12-21 12:32:50 -05:00
sch_prio.c net: sch: prio: Add offload ability for grafting a child 2018-02-28 12:06:01 -05:00
sch_qfq.c net: sch: api: add extack support in qdisc_create_dflt 2017-12-21 12:32:51 -05:00
sch_red.c net: sched: red: don't reset the backlog on every stat dump 2018-01-17 14:29:32 -05:00
sch_sfb.c net: sch: api: add extack support in qdisc_create_dflt 2017-12-21 12:32:51 -05:00
sch_sfq.c net: sch: api: add extack support in tcf_block_get 2017-12-21 12:32:51 -05:00
sch_tbf.c net: sched: tbf: handle GSO_BY_FRAGS case in enqueue 2018-03-04 17:49:17 -05:00
sch_teql.c net: sched: sch: add extack for init callback 2017-12-21 12:32:50 -05:00