linux/net/sched
valis 8fc134fee2 net: sched: sch_qfq: Fix UAF in qfq_dequeue()
When the plug qdisc is used as a class of the qfq qdisc it could trigger a
UAF. This issue can be reproduced with following commands:

  tc qdisc add dev lo root handle 1: qfq
  tc class add dev lo parent 1: classid 1:1 qfq weight 1 maxpkt 512
  tc qdisc add dev lo parent 1:1 handle 2: plug
  tc filter add dev lo parent 1: basic classid 1:1
  ping -c1 127.0.0.1

and boom:

[  285.353793] BUG: KASAN: slab-use-after-free in qfq_dequeue+0xa7/0x7f0
[  285.354910] Read of size 4 at addr ffff8880bad312a8 by task ping/144
[  285.355903]
[  285.356165] CPU: 1 PID: 144 Comm: ping Not tainted 6.5.0-rc3+ #4
[  285.357112] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014
[  285.358376] Call Trace:
[  285.358773]  <IRQ>
[  285.359109]  dump_stack_lvl+0x44/0x60
[  285.359708]  print_address_description.constprop.0+0x2c/0x3c0
[  285.360611]  kasan_report+0x10c/0x120
[  285.361195]  ? qfq_dequeue+0xa7/0x7f0
[  285.361780]  qfq_dequeue+0xa7/0x7f0
[  285.362342]  __qdisc_run+0xf1/0x970
[  285.362903]  net_tx_action+0x28e/0x460
[  285.363502]  __do_softirq+0x11b/0x3de
[  285.364097]  do_softirq.part.0+0x72/0x90
[  285.364721]  </IRQ>
[  285.365072]  <TASK>
[  285.365422]  __local_bh_enable_ip+0x77/0x90
[  285.366079]  __dev_queue_xmit+0x95f/0x1550
[  285.366732]  ? __pfx_csum_and_copy_from_iter+0x10/0x10
[  285.367526]  ? __pfx___dev_queue_xmit+0x10/0x10
[  285.368259]  ? __build_skb_around+0x129/0x190
[  285.368960]  ? ip_generic_getfrag+0x12c/0x170
[  285.369653]  ? __pfx_ip_generic_getfrag+0x10/0x10
[  285.370390]  ? csum_partial+0x8/0x20
[  285.370961]  ? raw_getfrag+0xe5/0x140
[  285.371559]  ip_finish_output2+0x539/0xa40
[  285.372222]  ? __pfx_ip_finish_output2+0x10/0x10
[  285.372954]  ip_output+0x113/0x1e0
[  285.373512]  ? __pfx_ip_output+0x10/0x10
[  285.374130]  ? icmp_out_count+0x49/0x60
[  285.374739]  ? __pfx_ip_finish_output+0x10/0x10
[  285.375457]  ip_push_pending_frames+0xf3/0x100
[  285.376173]  raw_sendmsg+0xef5/0x12d0
[  285.376760]  ? do_syscall_64+0x40/0x90
[  285.377359]  ? __static_call_text_end+0x136578/0x136578
[  285.378173]  ? do_syscall_64+0x40/0x90
[  285.378772]  ? kasan_enable_current+0x11/0x20
[  285.379469]  ? __pfx_raw_sendmsg+0x10/0x10
[  285.380137]  ? __sock_create+0x13e/0x270
[  285.380673]  ? __sys_socket+0xf3/0x180
[  285.381174]  ? __x64_sys_socket+0x3d/0x50
[  285.381725]  ? entry_SYSCALL_64_after_hwframe+0x6e/0xd8
[  285.382425]  ? __rcu_read_unlock+0x48/0x70
[  285.382975]  ? ip4_datagram_release_cb+0xd8/0x380
[  285.383608]  ? __pfx_ip4_datagram_release_cb+0x10/0x10
[  285.384295]  ? preempt_count_sub+0x14/0xc0
[  285.384844]  ? __list_del_entry_valid+0x76/0x140
[  285.385467]  ? _raw_spin_lock_bh+0x87/0xe0
[  285.386014]  ? __pfx__raw_spin_lock_bh+0x10/0x10
[  285.386645]  ? release_sock+0xa0/0xd0
[  285.387148]  ? preempt_count_sub+0x14/0xc0
[  285.387712]  ? freeze_secondary_cpus+0x348/0x3c0
[  285.388341]  ? aa_sk_perm+0x177/0x390
[  285.388856]  ? __pfx_aa_sk_perm+0x10/0x10
[  285.389441]  ? check_stack_object+0x22/0x70
[  285.390032]  ? inet_send_prepare+0x2f/0x120
[  285.390603]  ? __pfx_inet_sendmsg+0x10/0x10
[  285.391172]  sock_sendmsg+0xcc/0xe0
[  285.391667]  __sys_sendto+0x190/0x230
[  285.392168]  ? __pfx___sys_sendto+0x10/0x10
[  285.392727]  ? kvm_clock_get_cycles+0x14/0x30
[  285.393328]  ? set_normalized_timespec64+0x57/0x70
[  285.393980]  ? _raw_spin_unlock_irq+0x1b/0x40
[  285.394578]  ? __x64_sys_clock_gettime+0x11c/0x160
[  285.395225]  ? __pfx___x64_sys_clock_gettime+0x10/0x10
[  285.395908]  ? _copy_to_user+0x3e/0x60
[  285.396432]  ? exit_to_user_mode_prepare+0x1a/0x120
[  285.397086]  ? syscall_exit_to_user_mode+0x22/0x50
[  285.397734]  ? do_syscall_64+0x71/0x90
[  285.398258]  __x64_sys_sendto+0x74/0x90
[  285.398786]  do_syscall_64+0x64/0x90
[  285.399273]  ? exit_to_user_mode_prepare+0x1a/0x120
[  285.399949]  ? syscall_exit_to_user_mode+0x22/0x50
[  285.400605]  ? do_syscall_64+0x71/0x90
[  285.401124]  entry_SYSCALL_64_after_hwframe+0x6e/0xd8
[  285.401807] RIP: 0033:0x495726
[  285.402233] Code: ff ff ff f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b8 0f 1f 00 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 11 b8 2c 00 00 00 0f 09
[  285.404683] RSP: 002b:00007ffcc25fb618 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
[  285.405677] RAX: ffffffffffffffda RBX: 0000000000000040 RCX: 0000000000495726
[  285.406628] RDX: 0000000000000040 RSI: 0000000002518750 RDI: 0000000000000000
[  285.407565] RBP: 00000000005205ef R08: 00000000005f8838 R09: 000000000000001c
[  285.408523] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000002517634
[  285.409460] R13: 00007ffcc25fb6f0 R14: 0000000000000003 R15: 0000000000000000
[  285.410403]  </TASK>
[  285.410704]
[  285.410929] Allocated by task 144:
[  285.411402]  kasan_save_stack+0x1e/0x40
[  285.411926]  kasan_set_track+0x21/0x30
[  285.412442]  __kasan_slab_alloc+0x55/0x70
[  285.412973]  kmem_cache_alloc_node+0x187/0x3d0
[  285.413567]  __alloc_skb+0x1b4/0x230
[  285.414060]  __ip_append_data+0x17f7/0x1b60
[  285.414633]  ip_append_data+0x97/0xf0
[  285.415144]  raw_sendmsg+0x5a8/0x12d0
[  285.415640]  sock_sendmsg+0xcc/0xe0
[  285.416117]  __sys_sendto+0x190/0x230
[  285.416626]  __x64_sys_sendto+0x74/0x90
[  285.417145]  do_syscall_64+0x64/0x90
[  285.417624]  entry_SYSCALL_64_after_hwframe+0x6e/0xd8
[  285.418306]
[  285.418531] Freed by task 144:
[  285.418960]  kasan_save_stack+0x1e/0x40
[  285.419469]  kasan_set_track+0x21/0x30
[  285.419988]  kasan_save_free_info+0x27/0x40
[  285.420556]  ____kasan_slab_free+0x109/0x1a0
[  285.421146]  kmem_cache_free+0x1c2/0x450
[  285.421680]  __netif_receive_skb_core+0x2ce/0x1870
[  285.422333]  __netif_receive_skb_one_core+0x97/0x140
[  285.423003]  process_backlog+0x100/0x2f0
[  285.423537]  __napi_poll+0x5c/0x2d0
[  285.424023]  net_rx_action+0x2be/0x560
[  285.424510]  __do_softirq+0x11b/0x3de
[  285.425034]
[  285.425254] The buggy address belongs to the object at ffff8880bad31280
[  285.425254]  which belongs to the cache skbuff_head_cache of size 224
[  285.426993] The buggy address is located 40 bytes inside of
[  285.426993]  freed 224-byte region [ffff8880bad31280, ffff8880bad31360)
[  285.428572]
[  285.428798] The buggy address belongs to the physical page:
[  285.429540] page:00000000f4b77674 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0xbad31
[  285.430758] flags: 0x100000000000200(slab|node=0|zone=1)
[  285.431447] page_type: 0xffffffff()
[  285.431934] raw: 0100000000000200 ffff88810094a8c0 dead000000000122 0000000000000000
[  285.432757] raw: 0000000000000000 00000000800c000c 00000001ffffffff 0000000000000000
[  285.433562] page dumped because: kasan: bad access detected
[  285.434144]
[  285.434320] Memory state around the buggy address:
[  285.434828]  ffff8880bad31180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  285.435580]  ffff8880bad31200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  285.436264] >ffff8880bad31280: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  285.436777]                                   ^
[  285.437106]  ffff8880bad31300: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
[  285.437616]  ffff8880bad31380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  285.438126] ==================================================================
[  285.438662] Disabling lock debugging due to kernel taint

Fix this by:
1. Changing sch_plug's .peek handler to qdisc_peek_dequeued(), a
function compatible with non-work-conserving qdiscs
2. Checking the return value of qdisc_dequeue_peeked() in sch_qfq.

Fixes: 462dbc9101 ("pkt_sched: QFQ Plus: fair-queueing service at DRR cost")
Reported-by: valis <sec@valis.email>
Signed-off-by: valis <sec@valis.email>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://lore.kernel.org/r/20230901162237.11525-1-jhs@mojatatu.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-09-05 08:54:12 +02:00
..
act_api.c net: sched: Replace strlcpy with strscpy 2023-07-10 08:23:53 +01:00
act_bpf.c
act_connmark.c net/sched: act_connmark: handle errno on tcf_idr_check_alloc 2023-03-01 08:19:09 +00:00
act_csum.c net: skbuff: hide csum_not_inet when CONFIG_IP_SCTP not set 2023-04-19 13:04:30 +01:00
act_ct.c net: sched: set IPS_CONFIRMED in tmpl status only when commit is set in act_ct 2023-07-20 10:06:36 +02:00
act_ctinfo.c net/sched: act_ctinfo: use percpu stats 2023-02-13 20:09:01 -08:00
act_gact.c
act_gate.c net/sched: act_gate: use percpu stats 2023-02-16 10:39:28 +01:00
act_ife.c
act_ipt.c net/sched: act_ipt: zero skb->cb before calling target 2023-06-29 12:10:37 +02:00
act_meta_mark.c
act_meta_skbprio.c
act_meta_skbtcindex.c
act_mirred.c net/sched: act_mirred: Add carrier check 2023-05-01 07:26:10 +01:00
act_mpls.c net/sched: remove two skb_mac_header() uses 2023-03-22 22:43:23 -07:00
act_nat.c net/sched: act_nat: transition to percpu stats and rcu 2023-02-16 10:39:28 +01:00
act_pedit.c net/sched: act_pedit: Add size check for TCA_PEDIT_PARMS_EX 2023-07-04 10:31:38 +02:00
act_police.c net: move gso declarations and functions to their own files 2023-06-10 00:11:41 -07:00
act_sample.c net/sched: act_sample: fix action bind logic 2023-02-26 18:27:45 +00:00
act_simple.c
act_skbedit.c
act_skbmod.c
act_tunnel_key.c net/sched: act_tunnel_key: add support for "don't fragment" 2023-03-30 23:24:24 -07:00
act_vlan.c
cls_api.c net/sched: cls_api: Fix lockup on flushing explicitly created chain 2023-06-14 23:03:16 -07:00
cls_basic.c
cls_bpf.c net: sched: cls_bpf: Undo tcf_bind_filter in case of an error 2023-07-17 07:33:39 +01:00
cls_cgroup.c
cls_flow.c
cls_flower.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2023-08-03 14:34:37 -07:00
cls_fw.c net/sched: cls_fw: No longer copy tcf_result on update to avoid use-after-free 2023-07-31 20:10:36 -07:00
cls_matchall.c net: sched: cls_matchall: Undo tcf_bind_filter in case of failure after mall_set_parms 2023-07-17 07:33:38 +01:00
cls_route.c net/sched: cls_route: No longer copy tcf_result on update to avoid use-after-free 2023-07-31 20:10:37 -07:00
cls_u32.c net/sched: cls_u32: No longer copy tcf_result on update to avoid use-after-free 2023-07-31 20:10:36 -07:00
em_canid.c
em_cmp.c
em_ipset.c
em_ipt.c
em_meta.c net: annotate data-races around sk->sk_lingertime 2023-08-21 07:41:57 +01:00
em_nbyte.c
em_text.c
em_u32.c
ematch.c
Kconfig bpf: Add fd-based tcx multi-prog infra with link support 2023-07-19 10:07:27 -07:00
Makefile net/sched: Retire rsvp classifier 2023-02-16 09:27:07 +01:00
sch_api.c net/sched: fix a qdisc modification with ambiguous command request 2023-08-23 09:44:48 +01:00
sch_blackhole.c
sch_cake.c net: move gso declarations and functions to their own files 2023-06-10 00:11:41 -07:00
sch_cbs.c
sch_choke.c
sch_codel.c
sch_drr.c net/sched: sch_drr: warn about class in use while deleting 2023-08-01 10:47:24 +02:00
sch_etf.c
sch_ets.c
sch_fifo.c
sch_fq_codel.c
sch_fq_pie.c net/sched: fq_pie: avoid stalls in fq_pie_timer() 2023-08-31 11:21:52 +02:00
sch_fq.c net/sched: sch_fq: fix integer overflow of "credit" 2023-04-21 20:24:29 -07:00
sch_frag.c
sch_generic.c net/sched: qdisc_destroy() old ingress and clsact Qdiscs before grafting 2023-06-14 10:31:39 +02:00
sch_gred.c
sch_hfsc.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2023-08-29 07:44:56 +02:00
sch_hhf.c
sch_htb.c net/sched: sch_htb: warn about class in use while deleting 2023-08-01 10:47:24 +02:00
sch_ingress.c tcx: Fix splat in ingress_destroy upon tcx_entry_free 2023-07-24 11:42:35 -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: mqprio: allow per-TC user input of FP adminStatus 2023-04-13 22:22:10 -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 net/sched: mqprio: Add length check for TCA_MQPRIO_{MAX/MIN}_RATE64 2023-07-26 22:08:14 -07:00
sch_multiq.c
sch_netem.c netem: use seeded PRNG for correlated loss events 2023-08-17 19:15:06 -07:00
sch_pie.c net: sched: add rcu annotations around qdisc->qdisc_sleeping 2023-06-07 10:25:39 +01:00
sch_plug.c net: sched: sch_qfq: Fix UAF in qfq_dequeue() 2023-09-05 08:54:12 +02:00
sch_prio.c
sch_qfq.c net: sched: sch_qfq: Fix UAF in qfq_dequeue() 2023-09-05 08:54:12 +02:00
sch_red.c net: sched: add rcu annotations around qdisc->qdisc_sleeping 2023-06-07 10:25:39 +01:00
sch_sfb.c
sch_sfq.c net: sched: add rcu annotations around qdisc->qdisc_sleeping 2023-06-07 10:25:39 +01:00
sch_skbprio.c
sch_taprio.c net/sched: taprio: dump class stats for the actual q->qdiscs[] 2023-08-09 15:59:21 -07:00
sch_tbf.c net: move gso declarations and functions to their own files 2023-06-10 00:11:41 -07:00
sch_teql.c net: sched: add rcu annotations around qdisc->qdisc_sleeping 2023-06-07 10:25:39 +01:00