linux/net/sched
Stephen Hemminger c07ff8592d netem: fix return value if duplicate enqueue fails
There is a bug in netem_enqueue() introduced by
commit 5845f70638 ("net: netem: fix skb length BUG_ON in __skb_to_sgvec")
that can lead to a use-after-free.

This commit made netem_enqueue() always return NET_XMIT_SUCCESS
when a packet is duplicated, which can cause the parent qdisc's q.qlen
to be mistakenly incremented. When this happens qlen_notify() may be
skipped on the parent during destruction, leaving a dangling pointer
for some classful qdiscs like DRR.

There are two ways for the bug happen:

- If the duplicated packet is dropped by rootq->enqueue() and then
  the original packet is also dropped.
- If rootq->enqueue() sends the duplicated packet to a different qdisc
  and the original packet is dropped.

In both cases NET_XMIT_SUCCESS is returned even though no packets
are enqueued at the netem qdisc.

The fix is to defer the enqueue of the duplicate packet until after
the original packet has been guaranteed to return NET_XMIT_SUCCESS.

Fixes: 5845f70638 ("net: netem: fix skb length BUG_ON in __skb_to_sgvec")
Reported-by: Budimir Markovic <markovicbudimir@gmail.com>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20240819175753.5151-1-stephen@networkplumber.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-08-20 17:03:34 -07:00
..
act_api.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2024-06-20 13:49:59 -07:00
act_bpf.c net: Rename mono_delivery_time to tstamp_type for scalabilty 2024-05-23 14:14:23 -07:00
act_connmark.c net/sched: Add module aliases for cls_,sch_,act_ modules 2024-02-02 10:57:55 -08:00
act_csum.c net/sched: Add module aliases for cls_,sch_,act_ modules 2024-02-02 10:57:55 -08:00
act_ct.c sched: act_ct: take care of padding in struct zones_ht_key 2024-07-26 11:22:57 +01:00
act_ctinfo.c net/sched: Add module aliases for cls_,sch_,act_ modules 2024-02-02 10:57:55 -08:00
act_gact.c net/sched: Add module aliases for cls_,sch_,act_ modules 2024-02-02 10:57:55 -08:00
act_gate.c net/sched: Add module aliases for cls_,sch_,act_ modules 2024-02-02 10:57:55 -08:00
act_ife.c net/sched: Add module aliases for cls_,sch_,act_ modules 2024-02-02 10:57:55 -08:00
act_meta_mark.c
act_meta_skbprio.c
act_meta_skbtcindex.c
act_mirred.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2024-02-22 15:29:26 -08:00
act_mpls.c net/sched: Add module aliases for cls_,sch_,act_ modules 2024-02-02 10:57:55 -08:00
act_nat.c net/sched: Add module aliases for cls_,sch_,act_ modules 2024-02-02 10:57:55 -08:00
act_pedit.c net: sched: Annotate struct tc_pedit with __counted_by 2024-02-19 10:58:24 +00:00
act_police.c net/sched: Add module aliases for cls_,sch_,act_ modules 2024-02-02 10:57:55 -08:00
act_sample.c net: sched: act_sample: add action cookie to sample 2024-07-05 17:45:47 -07:00
act_simple.c net/sched: Add module aliases for cls_,sch_,act_ modules 2024-02-02 10:57:55 -08:00
act_skbedit.c net/sched: Add module aliases for cls_,sch_,act_ modules 2024-02-02 10:57:55 -08:00
act_skbmod.c net/sched: act_skbmod: convert comma to semicolon 2024-07-11 17:12:15 -07:00
act_tunnel_key.c ip_tunnel: convert __be16 tunnel flags to bitmaps 2024-04-01 10:49:28 +01:00
act_vlan.c net/sched: Add module aliases for cls_,sch_,act_ modules 2024-02-02 10:57:55 -08:00
cls_api.c net: sched: cls_api: fix slab-use-after-free in fl_dump_key 2024-04-10 08:28:26 +01:00
cls_basic.c net/sched: Add module aliases for cls_,sch_,act_ modules 2024-02-02 10:57:55 -08:00
cls_bpf.c net: Rename mono_delivery_time to tstamp_type for scalabilty 2024-05-23 14:14:23 -07:00
cls_cgroup.c net/sched: Add module aliases for cls_,sch_,act_ modules 2024-02-02 10:57:55 -08:00
cls_flow.c net/sched: Add module aliases for cls_,sch_,act_ modules 2024-02-02 10:57:55 -08:00
cls_flower.c net/sched: cls_flower: propagate tca[TCA_OPTIONS] to NL_REQ_ATTR_CHECK 2024-07-15 09:14:39 -07:00
cls_fw.c net/sched: Add module aliases for cls_,sch_,act_ modules 2024-02-02 10:57:55 -08:00
cls_matchall.c net/sched: Add module aliases for cls_,sch_,act_ modules 2024-02-02 10:57:55 -08:00
cls_route.c net/sched: Add module aliases for cls_,sch_,act_ modules 2024-02-02 10:57:55 -08:00
cls_u32.c net/sched: Add module aliases for cls_,sch_,act_ modules 2024-02-02 10:57:55 -08:00
em_canid.c net: fill in MODULE_DESCRIPTION()s for net/sched 2024-02-09 14:12:02 -08:00
em_cmp.c net: fill in MODULE_DESCRIPTION()s for net/sched 2024-02-09 14:12:02 -08:00
em_ipset.c
em_ipt.c
em_meta.c net: fill in MODULE_DESCRIPTION()s for net/sched 2024-02-09 14:12:02 -08:00
em_nbyte.c net: fill in MODULE_DESCRIPTION()s for net/sched 2024-02-09 14:12:02 -08:00
em_text.c net: fill in MODULE_DESCRIPTION()s for net/sched 2024-02-09 14:12:02 -08:00
em_u32.c net: fill in MODULE_DESCRIPTION()s for net/sched 2024-02-09 14:12:02 -08:00
ematch.c net_sched: reject TCF_EM_SIMPLE case for complex ematch module 2022-12-19 09:43:18 +00:00
Kconfig net: sched: Remove NET_ACT_IPT from Kconfig 2024-02-13 11:24:35 +01:00
Makefile net/sched: Retire ipt action 2024-01-02 12:41:16 +00:00
sch_api.c rtnetlink: do not depend on RTNL for IFLA_TXQLEN output 2024-05-07 11:14:50 +02:00
sch_blackhole.c
sch_cake.c net_sched: cake: implement lockless cake_dump() 2024-04-19 11:34:07 +01:00
sch_cbs.c net_sched: sch_cbs: implement lockless cbs_dump() 2024-04-19 11:34:07 +01:00
sch_choke.c net_sched: sch_choke: implement lockless choke_dump() 2024-04-19 11:34:07 +01:00
sch_codel.c net_sched: sch_codel: implement lockless codel_dump() 2024-04-19 11:34:07 +01:00
sch_drr.c net/sched: Add module aliases for cls_,sch_,act_ modules 2024-02-02 10:57:55 -08:00
sch_etf.c net_sched: sch_tfs: implement lockless etf_dump() 2024-04-19 11:34:07 +01:00
sch_ets.c net_sched: sch_ets: implement lockless ets_dump() 2024-04-19 11:34:07 +01:00
sch_fifo.c net_sched: sch_fifo: implement lockless __fifo_dump() 2024-04-19 11:34:07 +01:00
sch_fq_codel.c net_sched: sch_fq_codel: implement lockless fq_codel_dump() 2024-04-19 11:34:07 +01:00
sch_fq_pie.c net_sched: sch_fq_pie: implement lockless fq_pie_dump() 2024-04-19 11:34:07 +01:00
sch_fq.c net_sched: sch_fq: implement lockless fq_dump() 2024-04-19 11:34:07 +01:00
sch_frag.c net: dst: remove unnecessary input parameter in dst_alloc and dst_init 2023-09-12 11:42:25 +02:00
sch_generic.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2024-06-13 13:13:46 -07:00
sch_gred.c net/sched: Add module aliases for cls_,sch_,act_ modules 2024-02-02 10:57:55 -08:00
sch_hfsc.c net_sched: sch_hfsc: implement lockless accesses to q->defcls 2024-04-19 11:34:08 +01:00
sch_hhf.c net_sched: sch_hhf: implement lockless hhf_dump() 2024-04-19 11:34:08 +01:00
sch_htb.c net/sched: fix false lockdep warning on qdisc root lock 2024-04-26 10:46:41 +02:00
sch_ingress.c bpf: Fix too early release of tcx_entry 2024-07-08 14:07:31 -07:00
sch_mq.c net: sched: add rcu annotations around qdisc->qdisc_sleeping 2023-06-07 10:25:39 +01:00
sch_mqprio_lib.c net: sched: Fill in missing MODULE_DESCRIPTION for qdiscs 2023-11-01 21:49:09 -07:00
sch_mqprio_lib.h net/sched: mqprio: allow per-TC user input of FP adminStatus 2023-04-13 22:22:10 -07:00
sch_mqprio.c netlink: introduce type-checking attribute iteration 2024-03-29 15:06:02 -07:00
sch_multiq.c net: sched: sch_multiq: fix possible OOB write in multiq_tune() 2024-06-05 10:50:19 +01:00
sch_netem.c netem: fix return value if duplicate enqueue fails 2024-08-20 17:03:34 -07:00
sch_pie.c net_sched: sch_pie: implement lockless pie_dump() 2024-04-19 11:34:08 +01:00
sch_plug.c net/sched: Add module aliases for cls_,sch_,act_ modules 2024-02-02 10:57:55 -08:00
sch_prio.c net/sched: Add module aliases for cls_,sch_,act_ modules 2024-02-02 10:57:55 -08:00
sch_qfq.c net/sched: Add module aliases for cls_,sch_,act_ modules 2024-02-02 10:57:55 -08:00
sch_red.c net/sched: Add module aliases for cls_,sch_,act_ modules 2024-02-02 10:57:55 -08:00
sch_sfb.c net/sched: Add module aliases for cls_,sch_,act_ modules 2024-02-02 10:57:55 -08:00
sch_sfq.c net_sched: sch_sfq: annotate data-races around q->perturb_period 2024-05-02 19:01:35 -07:00
sch_skbprio.c net_sched: sch_skbprio: implement lockless skbprio_dump() 2024-04-19 11:34:08 +01:00
sch_taprio.c net: Add struct kernel_ethtool_ts_info 2024-07-15 08:02:26 -07:00
sch_tbf.c net/sched: Add module aliases for cls_,sch_,act_ modules 2024-02-02 10:57:55 -08:00
sch_teql.c net: annotate writes on dev->mtu from ndo_change_mtu() 2024-05-07 16:19:14 -07:00