linux/net
Eric Dumazet 76feedc74b net/sched: accept TCA_STAB only for root qdisc
[ Upstream commit 3cb7cf1540 ]

Most qdiscs maintain their backlog using qdisc_pkt_len(skb)
on the assumption it is invariant between the enqueue()
and dequeue() handlers.

Unfortunately syzbot can crash a host rather easily using
a TBF + SFQ combination, with an STAB on SFQ [1]

We can't support TCA_STAB on arbitrary level, this would
require to maintain per-qdisc storage.

[1]
[   88.796496] BUG: kernel NULL pointer dereference, address: 0000000000000000
[   88.798611] #PF: supervisor read access in kernel mode
[   88.799014] #PF: error_code(0x0000) - not-present page
[   88.799506] PGD 0 P4D 0
[   88.799829] Oops: Oops: 0000 [#1] SMP NOPTI
[   88.800569] CPU: 14 UID: 0 PID: 2053 Comm: b371744477 Not tainted 6.12.0-rc1-virtme #1117
[   88.801107] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[   88.801779] RIP: 0010:sfq_dequeue (net/sched/sch_sfq.c:272 net/sched/sch_sfq.c:499) sch_sfq
[ 88.802544] Code: 0f b7 50 12 48 8d 04 d5 00 00 00 00 48 89 d6 48 29 d0 48 8b 91 c0 01 00 00 48 c1 e0 03 48 01 c2 66 83 7a 1a 00 7e c0 48 8b 3a <4c> 8b 07 4c 89 02 49 89 50 08 48 c7 47 08 00 00 00 00 48 c7 07 00
All code
========
   0:	0f b7 50 12          	movzwl 0x12(%rax),%edx
   4:	48 8d 04 d5 00 00 00 	lea    0x0(,%rdx,8),%rax
   b:	00
   c:	48 89 d6             	mov    %rdx,%rsi
   f:	48 29 d0             	sub    %rdx,%rax
  12:	48 8b 91 c0 01 00 00 	mov    0x1c0(%rcx),%rdx
  19:	48 c1 e0 03          	shl    $0x3,%rax
  1d:	48 01 c2             	add    %rax,%rdx
  20:	66 83 7a 1a 00       	cmpw   $0x0,0x1a(%rdx)
  25:	7e c0                	jle    0xffffffffffffffe7
  27:	48 8b 3a             	mov    (%rdx),%rdi
  2a:*	4c 8b 07             	mov    (%rdi),%r8		<-- trapping instruction
  2d:	4c 89 02             	mov    %r8,(%rdx)
  30:	49 89 50 08          	mov    %rdx,0x8(%r8)
  34:	48 c7 47 08 00 00 00 	movq   $0x0,0x8(%rdi)
  3b:	00
  3c:	48                   	rex.W
  3d:	c7                   	.byte 0xc7
  3e:	07                   	(bad)
	...

Code starting with the faulting instruction
===========================================
   0:	4c 8b 07             	mov    (%rdi),%r8
   3:	4c 89 02             	mov    %r8,(%rdx)
   6:	49 89 50 08          	mov    %rdx,0x8(%r8)
   a:	48 c7 47 08 00 00 00 	movq   $0x0,0x8(%rdi)
  11:	00
  12:	48                   	rex.W
  13:	c7                   	.byte 0xc7
  14:	07                   	(bad)
	...
[   88.803721] RSP: 0018:ffff9a1f892b7d58 EFLAGS: 00000206
[   88.804032] RAX: 0000000000000000 RBX: ffff9a1f8420c800 RCX: ffff9a1f8420c800
[   88.804560] RDX: ffff9a1f81bc1440 RSI: 0000000000000000 RDI: 0000000000000000
[   88.805056] RBP: ffffffffc04bb0e0 R08: 0000000000000001 R09: 00000000ff7f9a1f
[   88.805473] R10: 000000000001001b R11: 0000000000009a1f R12: 0000000000000140
[   88.806194] R13: 0000000000000001 R14: ffff9a1f886df400 R15: ffff9a1f886df4ac
[   88.806734] FS:  00007f445601a740(0000) GS:ffff9a2e7fd80000(0000) knlGS:0000000000000000
[   88.807225] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   88.807672] CR2: 0000000000000000 CR3: 000000050cc46000 CR4: 00000000000006f0
[   88.808165] Call Trace:
[   88.808459]  <TASK>
[   88.808710] ? __die (arch/x86/kernel/dumpstack.c:421 arch/x86/kernel/dumpstack.c:434)
[   88.809261] ? page_fault_oops (arch/x86/mm/fault.c:715)
[   88.809561] ? exc_page_fault (./arch/x86/include/asm/irqflags.h:26 ./arch/x86/include/asm/irqflags.h:87 ./arch/x86/include/asm/irqflags.h:147 arch/x86/mm/fault.c:1489 arch/x86/mm/fault.c:1539)
[   88.809806] ? asm_exc_page_fault (./arch/x86/include/asm/idtentry.h:623)
[   88.810074] ? sfq_dequeue (net/sched/sch_sfq.c:272 net/sched/sch_sfq.c:499) sch_sfq
[   88.810411] sfq_reset (net/sched/sch_sfq.c:525) sch_sfq
[   88.810671] qdisc_reset (./include/linux/skbuff.h:2135 ./include/linux/skbuff.h:2441 ./include/linux/skbuff.h:3304 ./include/linux/skbuff.h:3310 net/sched/sch_generic.c:1036)
[   88.810950] tbf_reset (./include/linux/timekeeping.h:169 net/sched/sch_tbf.c:334) sch_tbf
[   88.811208] qdisc_reset (./include/linux/skbuff.h:2135 ./include/linux/skbuff.h:2441 ./include/linux/skbuff.h:3304 ./include/linux/skbuff.h:3310 net/sched/sch_generic.c:1036)
[   88.811484] netif_set_real_num_tx_queues (./include/linux/spinlock.h:396 ./include/net/sch_generic.h:768 net/core/dev.c:2958)
[   88.811870] __tun_detach (drivers/net/tun.c:590 drivers/net/tun.c:673)
[   88.812271] tun_chr_close (drivers/net/tun.c:702 drivers/net/tun.c:3517)
[   88.812505] __fput (fs/file_table.c:432 (discriminator 1))
[   88.812735] task_work_run (kernel/task_work.c:230)
[   88.813016] do_exit (kernel/exit.c:940)
[   88.813372] ? trace_hardirqs_on (kernel/trace/trace_preemptirq.c:58 (discriminator 4))
[   88.813639] ? handle_mm_fault (./arch/x86/include/asm/irqflags.h:42 ./arch/x86/include/asm/irqflags.h:97 ./arch/x86/include/asm/irqflags.h:155 ./include/linux/memcontrol.h:1022 ./include/linux/memcontrol.h:1045 ./include/linux/memcontrol.h:1052 mm/memory.c:5928 mm/memory.c:6088)
[   88.813867] do_group_exit (kernel/exit.c:1070)
[   88.814138] __x64_sys_exit_group (kernel/exit.c:1099)
[   88.814490] x64_sys_call (??:?)
[   88.814791] do_syscall_64 (arch/x86/entry/common.c:52 (discriminator 1) arch/x86/entry/common.c:83 (discriminator 1))
[   88.815012] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
[   88.815495] RIP: 0033:0x7f44560f1975

Fixes: 175f9c1bba ("net_sched: Add size table for qdiscs")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Link: https://patch.msgid.link/20241007184130.3960565-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
History 2024-10-17 15:22:22 +02:00
..
6lowpan net: 6lowpan: constify lowpan_nhc structures 2022-06-09 21:53:28 +02:00
9p net/9p: fix uninit-value in p9_client_rpc() 2024-06-16 13:41:38 +02:00
802 mrp: introduce active flags to prevent UAF when applicant uninit 2022-12-31 13:33:02 +01:00
8021q vlan: skip nested type that is not IFLA_VLAN_QOS_MAPPING 2024-01-31 16:17:04 -08:00
appletalk appletalk: Fix Use-After-Free in atalk_ioctl 2023-12-20 17:00:19 +01:00
atm atm: Fix Use-After-Free in do_vcc_ioctl 2023-12-20 17:00:17 +01:00
ax25 ax25: Replace kfree() in ax25_dev_free() with ax25_dev_put() 2024-06-21 14:35:32 +02:00
batman-adv batman-adv: Don't accept TT entries for out-of-spec VIDs 2024-07-05 09:31:58 +02:00
bluetooth Bluetooth: RFCOMM: FIX possible deadlock in rfcomm_sk_state_change 2024-10-17 15:22:19 +02:00
bpf bpf: Set run context for rawtp test_run callback 2024-06-21 14:35:33 +02:00
bpfilter uaccess: remove CONFIG_SET_FS 2022-02-25 09:36:06 +01:00
bridge netfilter: br_netfilter: fix panic with metadata_dst skb 2024-10-17 15:22:19 +02:00
caif net: caif: Fix use-after-free in cfusbl_device_notify() 2023-03-17 08:50:24 +01:00
can can: bcm: Clear bo->bcm_proc_read after remove_proc_entry(). 2024-10-17 15:20:42 +02:00
ceph libceph: fix race between delayed_work() and ceph_monc_stop() 2024-07-18 13:18:41 +02:00
core net: add more sanity checks to qdisc_pkt_len_init() 2024-10-17 15:21:32 +02:00
dcb net: dcb: choose correct policy to parse DCB_ATTR_BCN 2023-08-11 12:08:17 +02:00
dccp tcp/dccp: do not care about families in inet_twsk_purge() 2024-08-29 17:30:44 +02:00
devlink devlink: remove reload failed checks in params get/set callbacks 2023-09-23 11:11:01 +02:00
dns_resolver keys, dns: Fix size check of V1 server-list header 2024-01-25 15:27:38 -08:00
dsa net: mscc: ocelot: use ocelot_xmit_get_vlan_info() also for FDMA and register injection 2024-08-29 17:30:43 +02:00
ethernet ethernet: Add helper for assigning packet type when dest address does not match device address 2024-05-02 16:29:29 +02:00
ethtool ethtool: check device is present when getting link settings 2024-09-04 13:25:01 +02:00
hsr hsr: Simplify code for announcing HSR nodes timer setup 2024-05-17 11:56:13 +02:00
ieee802154 net: ieee802154: fix error return code in dgram_bind() 2022-10-07 09:29:17 +02:00
ife net: sched: ife: fix potential use-after-free 2024-01-01 12:38:56 +00:00
ipv4 tcp: fix tcp_enter_recovery() to zero retrans_stamp when it's safe 2024-10-17 15:22:19 +02:00
ipv6 netfilter: nf_reject: Fix build warning when CONFIG_BRIDGE_NETFILTER=n 2024-10-17 15:22:16 +02:00
iucv s390/iucv: fix receive buffer virtual vs physical address confusion 2024-08-29 17:30:39 +02:00
kcm kcm: Serialise kcm_sendmsg() for the same socket. 2024-08-29 17:30:44 +02:00
key net: af_key: fix sadb_x_filter validation 2023-08-23 17:52:32 +02:00
l2tp l2tp: fix lockdep splat 2024-08-14 13:52:44 +02:00
l3mdev l3mdev: l3mdev_master_upper_ifindex_by_index_rcu should be using netdev_master_upper_dev_get_rcu 2022-04-15 14:27:24 -07:00
lapb net: lapb: Use list_for_each_entry() to simplify code in lapb_iface.c 2021-06-08 16:31:25 -07:00
llc llc: call sock_orphan() at release time 2024-02-05 20:13:01 +00:00
mac80211 wifi: mac80211: fix RCU list iterations 2024-10-17 15:21:39 +02:00
mac802154 net: mac802154: Fix racy device stats updates by DEV_STATS_INC() and DEV_STATS_ADD() 2024-07-25 09:49:17 +02:00
mctp net: mctp: test: Use correct skb for route input check 2024-08-29 17:30:44 +02:00
mpls net: mpls: error out if inner headers are not set 2024-04-13 13:05:27 +02:00
mptcp mptcp: pm: Fix uaf in __timer_delete_sync 2024-09-18 19:23:03 +02:00
ncsi net/ncsi: Fix the multi thread manner of NCSI driver 2024-06-21 14:35:33 +02:00
netfilter netfilter: ctnetlink: compile ctnetlink_label_size with CONFIG_NF_CONNTRACK_EVENTS 2024-10-17 15:21:14 +02:00
netlabel calipso: fix memory leak in netlbl_calipso_add_pass() 2024-01-25 15:27:20 -08:00
netlink netlink: hold nlk->cb_mutex longer in __netlink_dump_start() 2024-08-29 17:30:36 +02:00
netrom netrom: Fix a memory leak in nr_heartbeat_expiry() 2024-06-27 13:46:18 +02:00
nfc nfc: nci: Fix handling of zero-length payload packets in nci_rx_work() 2024-06-12 11:03:53 +02:00
nsh nsh: Restore skb->{protocol,data,mac_header} for outer header in nsh_gso_segment(). 2024-05-17 11:55:59 +02:00
openvswitch openvswitch: Set the skbuff pkt_type for proper pmtud support. 2024-06-12 11:03:51 +02:00
packet af_packet: Handle outgoing VLAN packets without hardware offloading 2024-08-03 08:49:31 +02:00
phonet phonet: fix rtm_phonet_notify() skb allocation 2024-05-17 11:56:12 +02:00
psample psample: Require 'CAP_NET_ADMIN' when joining "packets" group 2023-12-13 18:39:11 +01:00
qrtr net: qrtr: Update packets cloning when broadcasting 2024-10-17 15:21:13 +02:00
rds net:rds: Fix possible deadlock in rds_message_put 2024-08-29 17:30:20 +02:00
rfkill net: rfkill: gpio: set GPIO direction 2024-01-01 12:39:04 +00:00
rose net/rose: fix races in rose_kill_by_device() 2024-01-01 12:38:57 +00:00
rxrpc rxrpc: Fix response to PING RESPONSE ACKs to a dead call 2024-02-16 19:06:27 +01:00
sched net/sched: accept TCA_STAB only for root qdisc 2024-10-17 15:22:22 +02:00
sctp sctp: set sk_state back to CLOSED if autobind fails in sctp_listen_start 2024-10-17 15:21:33 +02:00
smc net/smc: set rmb's SG_MAX_SINGLE_ALLOC limitation only when CONFIG_ARCH_NO_SG_CHAIN is defined 2024-08-03 08:49:04 +02:00
strparser strparser: pad sk_skb_cb to avoid straddling cachelines 2022-07-08 18:38:44 -07:00
sunrpc sunrpc: use the struct net as the svc proc private 2024-08-19 06:00:05 +02:00
switchdev net: bridge: switchdev: Skip MDB replays of deferred events on offload 2024-03-01 13:26:35 +01:00
tipc tipc: guard against string buffer overrun 2024-10-17 15:21:38 +02:00
tls tls: fix missing memory barrier in tls_init 2024-06-12 11:03:53 +02:00
unix af_unix: Remove put_pid()/put_cred() in copy_peercred(). 2024-09-12 11:10:19 +02:00
vmw_vsock vsock/virtio: fix packet delivery to tap device 2024-04-10 16:28:25 +02:00
wireless wifi: cfg80211: Set correct chandef when starting CAC 2024-10-17 15:21:35 +02:00
x25 net/x25: fix incorrect parameter validation in the x25_getsockopt() function 2024-03-26 18:20:42 -04:00
xdp xsk: validate user input for XDP_{UMEM|COMPLETION}_FILL_RING 2024-04-17 11:18:23 +02:00
xfrm net: fix __dst_negative_advice() race 2024-06-16 13:41:40 +02:00
compat.c use less confusing names for iov_iter direction initializers 2023-02-09 11:28:04 +01:00
devres.c net: devres: Correct a grammatical error 2021-06-11 12:55:28 -07:00
Kconfig Remove DECnet support from kernel 2022-08-22 14:26:30 +01:00
Kconfig.debug net: make NET_(DEV|NS)_REFCNT_TRACKER depend on NET 2022-09-20 14:23:56 -07:00
Makefile devlink: move code to a dedicated directory 2023-08-30 16:11:00 +02:00
socket.c splice, net: Add a splice_eof op to file-ops and socket-ops 2024-01-10 17:10:27 +01:00
sysctl_net.c sysctl: treewide: drop unused argument ctl_table_root::set_ownership(table) 2024-08-11 12:35:51 +02:00