linux/net/sched
Jamal Hadi Salim 0279957171 net_sched: cls_route: disallow handle of 0
Follows up on:
https://lore.kernel.org/all/20220809170518.164662-1-cascardo@canonical.com/

handle of 0 implies from/to of universe realm which is not very
sensible.

Lets see what this patch will do:
$sudo tc qdisc add dev $DEV root handle 1:0 prio

//lets manufacture a way to insert handle of 0
$sudo tc filter add dev $DEV parent 1:0 protocol ip prio 100 \
route to 0 from 0 classid 1:10 action ok

//gets rejected...
Error: handle of 0 is not valid.
We have an error talking to the kernel, -1

//lets create a legit entry..
sudo tc filter add dev $DEV parent 1:0 protocol ip prio 100 route from 10 \
classid 1:10 action ok

//what did the kernel insert?
$sudo tc filter ls dev $DEV parent 1:0
filter protocol ip pref 100 route chain 0
filter protocol ip pref 100 route chain 0 fh 0x000a8000 flowid 1:10 from 10
	action order 1: gact action pass
	 random type none pass val 0
	 index 1 ref 1 bind 1

//Lets try to replace that legit entry with a handle of 0
$ sudo tc filter replace dev $DEV parent 1:0 protocol ip prio 100 \
handle 0x000a8000 route to 0 from 0 classid 1:10 action drop

Error: Replacing with handle of 0 is invalid.
We have an error talking to the kernel, -1

And last, lets run Cascardo's POC:
$ ./poc
0
0
-22
-22
-22

Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-08-15 11:46:30 +01:00
..
act_api.c net/sched: act_api: Notify user space if any actions were flushed before error 2022-06-27 21:51:23 -07:00
act_bpf.c bpf: Keep the (rcv) timestamp behavior for the existing tc-bpf@ingress 2022-03-03 14:38:48 +00:00
act_connmark.c flow_offload: fill flags to action structure 2021-12-19 14:08:47 +00:00
act_csum.c net/sched: act_api: Add extack to offload_act_setup() callback 2022-04-08 13:45:43 +01:00
act_ct.c net/sched: act_ct: set 'net' pointer when creating new nf_flow_table 2022-07-11 16:25:14 +02:00
act_ctinfo.c flow_offload: fill flags to action structure 2021-12-19 14:08:47 +00:00
act_gact.c net/sched: act_gact: Add extack messages for offload failure 2022-04-08 13:45:43 +01:00
act_gate.c net/sched: act_api: Add extack to offload_act_setup() callback 2022-04-08 13:45:43 +01:00
act_ife.c flow_offload: fill flags to action structure 2021-12-19 14:08:47 +00:00
act_ipt.c flow_offload: fill flags to action structure 2021-12-19 14:08:47 +00:00
act_meta_mark.c
act_meta_skbprio.c
act_meta_skbtcindex.c
act_mirred.c net: rename reference+tracking helpers 2022-06-09 21:52:55 -07:00
act_mpls.c net/sched: act_mpls: Add extack messages for offload failure 2022-04-08 13:45:43 +01:00
act_nat.c flow_offload: fill flags to action structure 2021-12-19 14:08:47 +00:00
act_pedit.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2022-05-19 11:23:59 -07:00
act_police.c net/sched: act_police: allow 'continue' action offload 2022-07-06 12:44:39 +01:00
act_sample.c net/sched: act_api: Add extack to offload_act_setup() callback 2022-04-08 13:45:43 +01:00
act_simple.c flow_offload: fill flags to action structure 2021-12-19 14:08:47 +00:00
act_skbedit.c net: sched: support hash selecting tx queue 2022-04-19 12:20:45 +02:00
act_skbmod.c flow_offload: fill flags to action structure 2021-12-19 14:08:47 +00:00
act_tunnel_key.c net/sched: act_tunnel_key: Add extack message for offload failure 2022-04-08 13:45:43 +01:00
act_vlan.c net/sched: act_vlan: Add extack message for offload failure 2022-04-08 13:45:43 +01:00
cls_api.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2022-07-21 13:03:39 -07:00
cls_basic.c net_sched: refactor TC action init API 2021-08-02 10:24:38 +01:00
cls_bpf.c bpf: Keep the (rcv) timestamp behavior for the existing tc-bpf@ingress 2022-03-03 14:38:48 +00:00
cls_cgroup.c net_sched: refactor TC action init API 2021-08-02 10:24:38 +01:00
cls_flow.c net_sched: refactor TC action init API 2021-08-02 10:24:38 +01:00
cls_flower.c net/sched: flower: Add PPPoE filter 2022-07-26 10:20:29 -07:00
cls_fw.c net_sched: refactor TC action init API 2021-08-02 10:24:38 +01:00
cls_matchall.c net/sched: matchall: Avoid overwriting error messages 2022-04-08 13:45:43 +01:00
cls_route.c net_sched: cls_route: disallow handle of 0 2022-08-15 11:46:30 +01:00
cls_rsvp6.c
cls_rsvp.c
cls_rsvp.h net_sched: refactor TC action init API 2021-08-02 10:24:38 +01:00
cls_tcindex.c net_sched: refactor TC action init API 2021-08-02 10:24:38 +01:00
cls_u32.c net/sched: cls_u32: fix possible leak in u32_init_knode() 2022-04-15 14:26:11 -07:00
em_canid.c net: sched: kerneldoc fixes 2020-07-13 17:20:40 -07:00
em_cmp.c net: sched: fix misspellings using misspell-fixer tool 2020-11-10 17:00:28 -08:00
em_ipset.c sched: consistently handle layer3 header accesses in the presence of VLANs 2020-07-03 14:34:53 -07:00
em_ipt.c sched: consistently handle layer3 header accesses in the presence of VLANs 2020-07-03 14:34:53 -07:00
em_meta.c net_sched: em_meta: add READ_ONCE() in var_sk_bound_if() 2022-05-16 10:31:06 +01:00
em_nbyte.c net: sched: Return the correct errno code 2021-02-06 11:15:28 -08:00
em_text.c
em_u32.c
ematch.c net: sched: Fix spelling mistakes 2021-05-31 22:44:56 -07:00
Kconfig net: sched: incorrect Kconfig dependencies on Netfilter modules 2020-12-09 15:49:29 -08:00
Makefile net/sched: sch_frag: add generic packet fragment support. 2020-11-27 14:36:02 -08:00
sch_api.c net: rename reference+tracking helpers 2022-06-09 21:52:55 -07:00
sch_atm.c net: sched: Remove Qdisc::running sequence counter 2021-10-18 12:54:41 +01:00
sch_blackhole.c Revert "net: sched: Pass root lock to Qdisc_ops.enqueue" 2020-07-16 16:48:34 -07:00
sch_cake.c sch_cake: revise Diffserv docs 2022-01-07 08:41:29 -08:00
sch_cbq.c net/sched: sch_cbq: change the type of cbq_set_lss to void 2022-07-27 18:30:18 -07:00
sch_cbs.c net: don't include ethtool.h from netdevice.h 2020-11-23 17:27:04 -08:00
sch_choke.c net: sched: validate stab values 2021-03-10 15:47:52 -08:00
sch_codel.c Revert "net: sched: Pass root lock to Qdisc_ops.enqueue" 2020-07-16 16:48:34 -07:00
sch_drr.c net: sched: Remove Qdisc::running sequence counter 2021-10-18 12:54:41 +01:00
sch_dsmark.c net/sched: store the last executed chain also for clsact egress 2021-07-29 22:17:37 +01:00
sch_etf.c Revert "net: sched: Pass root lock to Qdisc_ops.enqueue" 2020-07-16 16:48:34 -07:00
sch_ets.c net/sched: sch_ets: don't remove idle classes from the round-robin list 2021-12-13 12:30:23 +00:00
sch_fifo.c net_sched: fix NULL deref in fifo_set_limit() 2021-10-01 14:59:10 -07:00
sch_fq_codel.c fq_codel: generalise ce_threshold marking for subset of traffic 2021-10-20 15:24:36 -07:00
sch_fq_pie.c net/sched: fq_pie: prevent dismantle issue 2021-12-09 08:01:00 -08:00
sch_fq.c Revert "net: sched: Pass root lock to Qdisc_ops.enqueue" 2020-07-16 16:48:34 -07:00
sch_frag.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2021-12-31 14:35:40 +00:00
sch_generic.c net/sched: remove hacks added to dev_trans_start() for bonding to work 2022-08-03 19:20:13 -07:00
sch_gred.c net: sched: gred: dynamically allocate tc_gred_qopt_offload 2021-10-27 12:06:52 -07:00
sch_hfsc.c net: sched: Remove Qdisc::running sequence counter 2021-10-18 12:54:41 +01:00
sch_hhf.c Revert "net: sched: Pass root lock to Qdisc_ops.enqueue" 2020-07-16 16:48:34 -07:00
sch_htb.c sch_htb: Fail on unsupported parameters when offload is requested 2022-01-25 20:00:02 -08:00
sch_ingress.c
sch_mq.c net: sched: Remove Qdisc::running sequence counter 2021-10-18 12:54:41 +01:00
sch_mqprio.c net: sched: Remove Qdisc::running sequence counter 2021-10-18 12:54:41 +01:00
sch_multiq.c net: sched: Remove Qdisc::running sequence counter 2021-10-18 12:54:41 +01:00
sch_netem.c net/sched: sch_netem: Fix arithmetic in netem_dump() for 32-bit platforms 2022-06-17 20:29:38 -07:00
sch_pie.c net: sched: fix misspellings using misspell-fixer tool 2020-11-10 17:00:28 -08:00
sch_plug.c Revert "net: sched: Pass root lock to Qdisc_ops.enqueue" 2020-07-16 16:48:34 -07:00
sch_prio.c net: sched: Remove Qdisc::running sequence counter 2021-10-18 12:54:41 +01:00
sch_qfq.c sch_qfq: prevent shift-out-of-bounds in qfq_init_qdisc 2022-01-04 12:36:51 +00:00
sch_red.c net: sched: validate stab values 2021-03-10 15:47:52 -08:00
sch_sfb.c net/sched: store the last executed chain also for clsact egress 2021-07-29 22:17:37 +01:00
sch_sfq.c net/sched: store the last executed chain also for clsact egress 2021-07-29 22:17:37 +01:00
sch_skbprio.c Revert "net: sched: Pass root lock to Qdisc_ops.enqueue" 2020-07-16 16:48:34 -07:00
sch_taprio.c time64.h: consolidate uses of PSEC_PER_NSEC 2022-06-30 21:18:16 -07:00
sch_tbf.c net: sch_tbf: Add a graft command 2021-10-19 12:24:51 +01:00
sch_teql.c net: sched: sch_teql: fix null-pointer dereference 2021-04-08 14:14:42 -07:00