linux-stable/net/sched
Aleksandr Nogikh eadd1befdd netem: fix zero division in tabledist
Currently it is possible to craft a special netlink RTM_NEWQDISC
command that can result in jitter being equal to 0x80000000. It is
enough to set the 32 bit jitter to 0x02000000 (it will later be
multiplied by 2^6) or just set the 64 bit jitter via
TCA_NETEM_JITTER64. This causes an overflow during the generation of
uniformly distributed numbers in tabledist(), which in turn leads to
division by zero (sigma != 0, but sigma * 2 is 0).

The related fragment of code needs 32-bit division - see commit
9b0ed89 ("netem: remove unnecessary 64 bit modulus"), so switching to
64 bit is not an option.

Fix the issue by keeping the value of jitter within the range that can
be adequately handled by tabledist() - [0;INT_MAX]. As negative std
deviation makes no sense, take the absolute value of the passed value
and cap it at INT_MAX. Inside tabledist(), switch to unsigned 32 bit
arithmetic in order to prevent overflows.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Aleksandr Nogikh <nogikh@google.com>
Reported-by: syzbot+ec762a6342ad0d3c0d8f@syzkaller.appspotmail.com
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
Link: https://lore.kernel.org/r/20201028170731.1383332-1-aleksandrnogikh@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-10-29 11:45:47 -07:00
..
act_api.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-10-05 18:40:01 -07:00
act_bpf.c net_sched: defer tcf_idr_insert() in tcf_action_init_1() 2020-09-24 19:46:21 -07:00
act_connmark.c net_sched: defer tcf_idr_insert() in tcf_action_init_1() 2020-09-24 19:46:21 -07:00
act_csum.c net_sched: defer tcf_idr_insert() in tcf_action_init_1() 2020-09-24 19:46:21 -07:00
act_ct.c net/sched: act_ct: Fix adding udp port mangle operation 2020-10-20 16:15:51 -07:00
act_ctinfo.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-10-05 18:40:01 -07:00
act_gact.c net_sched: defer tcf_idr_insert() in tcf_action_init_1() 2020-09-24 19:46:21 -07:00
act_gate.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-10-05 18:40:01 -07:00
act_ife.c net_sched: defer tcf_idr_insert() in tcf_action_init_1() 2020-09-24 19:46:21 -07:00
act_ipt.c net_sched: defer tcf_idr_insert() in tcf_action_init_1() 2020-09-24 19:46:21 -07:00
act_meta_mark.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
act_meta_skbprio.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
act_meta_skbtcindex.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
act_mirred.c net_sched: defer tcf_idr_insert() in tcf_action_init_1() 2020-09-24 19:46:21 -07:00
act_mpls.c net/sched: act_mpls: Add softdep on mpls_gso.ko 2020-10-27 17:17:06 -07:00
act_nat.c net_sched: defer tcf_idr_insert() in tcf_action_init_1() 2020-09-24 19:46:21 -07:00
act_pedit.c net_sched: defer tcf_idr_insert() in tcf_action_init_1() 2020-09-24 19:46:21 -07:00
act_police.c net_sched: defer tcf_idr_insert() in tcf_action_init_1() 2020-09-24 19:46:21 -07:00
act_sample.c net_sched: defer tcf_idr_insert() in tcf_action_init_1() 2020-09-24 19:46:21 -07:00
act_simple.c net_sched: defer tcf_idr_insert() in tcf_action_init_1() 2020-09-24 19:46:21 -07:00
act_skbedit.c net_sched: defer tcf_idr_insert() in tcf_action_init_1() 2020-09-24 19:46:21 -07:00
act_skbmod.c net_sched: defer tcf_idr_insert() in tcf_action_init_1() 2020-09-24 19:46:21 -07:00
act_tunnel_key.c net/sched: act_tunnel_key: fix OOB write in case of IPv6 ERSPAN tunnels 2020-10-20 21:10:41 -07:00
act_vlan.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-10-05 18:40:01 -07:00
cls_api.c net: protect tcf_block_unbind with block lock 2020-10-27 17:58:36 -07:00
cls_basic.c net_sched: fix ops->bind_class() implementations 2020-01-27 10:51:43 +01:00
cls_bpf.c net_sched: fix ops->bind_class() implementations 2020-01-27 10:51:43 +01:00
cls_cgroup.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
cls_flow.c Remove uninitialized_var() macro for v5.9-rc1 2020-08-04 13:49:43 -07:00
cls_flower.c net: sched: initialize with 0 before setting erspan md->u 2020-09-14 16:53:38 -07:00
cls_fw.c net_sched: fix ops->bind_class() implementations 2020-01-27 10:51:43 +01:00
cls_matchall.c net: qos offload add flow status with dropped count 2020-06-19 12:53:30 -07:00
cls_route.c net_sched: cls_route: remove the right filter from hashtable 2020-03-16 01:59:32 -07:00
cls_rsvp.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
cls_rsvp.h cls_rsvp: fix rsvp_policy 2020-02-01 12:25:06 -08:00
cls_rsvp6.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
cls_tcindex.c tcindex_change: Remove redundant null check 2020-06-22 20:55:09 -07:00
cls_u32.c net/sched: cls_u32: Replace one-element array with flexible-array member 2020-09-28 18:48:42 -07:00
em_canid.c net: sched: kerneldoc fixes 2020-07-13 17:20:40 -07:00
em_cmp.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
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 sched: consistently handle layer3 header accesses in the presence of VLANs 2020-07-03 14:34:53 -07:00
em_nbyte.c net: sched: Replace zero-length array with flexible-array member 2020-02-29 21:27:02 -08:00
em_text.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
em_u32.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
ematch.c net: sched: kerneldoc fixes 2020-07-13 17:20:40 -07:00
Kconfig net: sched: Allow changing default qdisc to FQ-PIE 2020-07-01 17:43:27 -07:00
Makefile net: qos: introduce a gate control flow action 2020-05-01 16:08:19 -07:00
sch_api.c sched: sch_api: add missing rcu read lock to silence the warning 2020-07-20 17:00:02 -07:00
sch_atm.c Revert "net: sched: Pass root lock to Qdisc_ops.enqueue" 2020-07-16 16:48:34 -07:00
sch_blackhole.c Revert "net: sched: Pass root lock to Qdisc_ops.enqueue" 2020-07-16 16:48:34 -07:00
sch_cake.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
sch_cbq.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 2020-08-05 20:13:21 -07:00
sch_cbs.c Revert "net: sched: Pass root lock to Qdisc_ops.enqueue" 2020-07-16 16:48:34 -07:00
sch_choke.c Revert "net: sched: Pass root lock to Qdisc_ops.enqueue" 2020-07-16 16:48:34 -07:00
sch_codel.c Revert "net: sched: Pass root lock to Qdisc_ops.enqueue" 2020-07-16 16:48:34 -07:00
sch_drr.c Revert "net: sched: Pass root lock to Qdisc_ops.enqueue" 2020-07-16 16:48:34 -07:00
sch_dsmark.c Revert "net: sched: Pass root lock to Qdisc_ops.enqueue" 2020-07-16 16:48:34 -07:00
sch_etf.c Revert "net: sched: Pass root lock to Qdisc_ops.enqueue" 2020-07-16 16:48:34 -07:00
sch_ets.c Revert "net: sched: Pass root lock to Qdisc_ops.enqueue" 2020-07-16 16:48:34 -07:00
sch_fifo.c Revert "net: sched: Pass root lock to Qdisc_ops.enqueue" 2020-07-16 16:48:34 -07:00
sch_fq.c Revert "net: sched: Pass root lock to Qdisc_ops.enqueue" 2020-07-16 16:48:34 -07:00
sch_fq_codel.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 2020-08-05 20:13:21 -07:00
sch_fq_pie.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 2020-08-05 20:13:21 -07:00
sch_generic.c net/sched: get rid of qdisc->padded 2020-10-09 08:08:08 -07:00
sch_gred.c Revert "net: sched: Pass root lock to Qdisc_ops.enqueue" 2020-07-16 16:48:34 -07:00
sch_hfsc.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 2020-08-05 20:13:21 -07:00
sch_hhf.c Revert "net: sched: Pass root lock to Qdisc_ops.enqueue" 2020-07-16 16:48:34 -07:00
sch_htb.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 2020-08-05 20:13:21 -07:00
sch_ingress.c net: sched: Pass ingress block to tcf_classify_ingress 2020-02-19 17:49:48 -08:00
sch_mq.c net: sched: fix dump qlen for sch_mq/sch_mqprio with NOLOCK subqueues 2019-12-03 11:53:55 -08:00
sch_mqprio.c mqprio: Fix out-of-bounds access in mqprio_dump 2019-12-06 11:58:45 -08:00
sch_multiq.c Revert "net: sched: Pass root lock to Qdisc_ops.enqueue" 2020-07-16 16:48:34 -07:00
sch_netem.c netem: fix zero division in tabledist 2020-10-29 11:45:47 -07:00
sch_pie.c Revert "net: sched: Pass root lock to Qdisc_ops.enqueue" 2020-07-16 16:48:34 -07:00
sch_plug.c Revert "net: sched: Pass root lock to Qdisc_ops.enqueue" 2020-07-16 16:48:34 -07:00
sch_prio.c Revert "net: sched: Pass root lock to Qdisc_ops.enqueue" 2020-07-16 16:48:34 -07:00
sch_qfq.c Revert "net: sched: Pass root lock to Qdisc_ops.enqueue" 2020-07-16 16:48:34 -07:00
sch_red.c net_sched: fix error path in red_init() 2020-08-28 07:16:46 -07:00
sch_sfb.c Revert "net: sched: Pass root lock to Qdisc_ops.enqueue" 2020-07-16 16:48:34 -07:00
sch_sfq.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 2020-08-05 20:13:21 -07:00
sch_skbprio.c Revert "net: sched: Pass root lock to Qdisc_ops.enqueue" 2020-07-16 16:48:34 -07:00
sch_taprio.c taprio: Fix allowing too small intervals 2020-09-11 17:21:51 -07:00
sch_tbf.c Revert "net: sched: Pass root lock to Qdisc_ops.enqueue" 2020-07-16 16:48:34 -07:00
sch_teql.c Revert "net: sched: Pass root lock to Qdisc_ops.enqueue" 2020-07-16 16:48:34 -07:00