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Davide Caratti 81fbdd4565 net/sched: sch_ets: don't remove idle classes from the round-robin list
[ Upstream commit c062f2a0b04d86c5b8c9d973bea43493eaca3d32 ]

Shuang reported that the following script:

 1) tc qdisc add dev ddd0 handle 10: parent 1: ets bands 8 strict 4 priomap 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7
 2) mausezahn ddd0  -A 10.10.10.1 -B 10.10.10.2 -c 0 -a own -b 00:c1:a0:c1:a0:00 -t udp &
 3) tc qdisc change dev ddd0 handle 10: ets bands 4 strict 2 quanta 2500 2500 priomap 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3

crashes systematically when line 2) is commented:

 list_del corruption, ffff8e028404bd30->next is LIST_POISON1 (dead000000000100)
 ------------[ cut here ]------------
 kernel BUG at lib/list_debug.c:47!
 invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
 CPU: 0 PID: 954 Comm: tc Not tainted 5.16.0-rc4+ #478
 Hardware name: Red Hat KVM, BIOS 1.11.1-4.module+el8.1.0+4066+0f1aadab 04/01/2014
 RIP: 0010:__list_del_entry_valid.cold.1+0x12/0x47
 Code: fe ff 0f 0b 48 89 c1 4c 89 c6 48 c7 c7 08 42 1b 87 e8 1d c5 fe ff 0f 0b 48 89 fe 48 89 c2 48 c7 c7 98 42 1b 87 e8 09 c5 fe ff <0f> 0b 48 c7 c7 48 43 1b 87 e8 fb c4 fe ff 0f 0b 48 89 f2 48 89 fe
 RSP: 0018:ffffae46807a3888 EFLAGS: 00010246
 RAX: 000000000000004e RBX: 0000000000000007 RCX: 0000000000000202
 RDX: 0000000000000000 RSI: ffffffff871ac536 RDI: 00000000ffffffff
 RBP: ffffae46807a3a10 R08: 0000000000000000 R09: c0000000ffff7fff
 R10: 0000000000000001 R11: ffffae46807a36a8 R12: ffff8e028404b800
 R13: ffff8e028404bd30 R14: dead000000000100 R15: ffff8e02fafa2400
 FS:  00007efdc92e4480(0000) GS:ffff8e02fb600000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000682f48 CR3: 00000001058be000 CR4: 0000000000350ef0
 Call Trace:
  <TASK>
  ets_qdisc_change+0x58b/0xa70 [sch_ets]
  tc_modify_qdisc+0x323/0x880
  rtnetlink_rcv_msg+0x169/0x4a0
  netlink_rcv_skb+0x50/0x100
  netlink_unicast+0x1a5/0x280
  netlink_sendmsg+0x257/0x4d0
  sock_sendmsg+0x5b/0x60
  ____sys_sendmsg+0x1f2/0x260
  ___sys_sendmsg+0x7c/0xc0
  __sys_sendmsg+0x57/0xa0
  do_syscall_64+0x3a/0x80
  entry_SYSCALL_64_after_hwframe+0x44/0xae
 RIP: 0033:0x7efdc8031338
 Code: 89 02 48 c7 c0 ff ff ff ff eb b5 0f 1f 80 00 00 00 00 f3 0f 1e fa 48 8d 05 25 43 2c 00 8b 00 85 c0 75 17 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 41 54 41 89 d4 55
 RSP: 002b:00007ffdf1ce9828 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
 RAX: ffffffffffffffda RBX: 0000000061b37a97 RCX: 00007efdc8031338
 RDX: 0000000000000000 RSI: 00007ffdf1ce9890 RDI: 0000000000000003
 RBP: 0000000000000000 R08: 0000000000000001 R09: 000000000078a940
 R10: 000000000000000c R11: 0000000000000246 R12: 0000000000000001
 R13: 0000000000688880 R14: 0000000000000000 R15: 0000000000000000
  </TASK>
 Modules linked in: sch_ets sch_tbf dummy rfkill iTCO_wdt iTCO_vendor_support intel_rapl_msr intel_rapl_common joydev pcspkr i2c_i801 virtio_balloon i2c_smbus lpc_ich ip_tables xfs libcrc32c crct10dif_pclmul crc32_pclmul crc32c_intel serio_raw ghash_clmulni_intel ahci libahci libata virtio_blk virtio_console virtio_net net_failover failover sunrpc dm_mirror dm_region_hash dm_log dm_mod [last unloaded: sch_ets]
 ---[ end trace f35878d1912655c2 ]---
 RIP: 0010:__list_del_entry_valid.cold.1+0x12/0x47
 Code: fe ff 0f 0b 48 89 c1 4c 89 c6 48 c7 c7 08 42 1b 87 e8 1d c5 fe ff 0f 0b 48 89 fe 48 89 c2 48 c7 c7 98 42 1b 87 e8 09 c5 fe ff <0f> 0b 48 c7 c7 48 43 1b 87 e8 fb c4 fe ff 0f 0b 48 89 f2 48 89 fe
 RSP: 0018:ffffae46807a3888 EFLAGS: 00010246
 RAX: 000000000000004e RBX: 0000000000000007 RCX: 0000000000000202
 RDX: 0000000000000000 RSI: ffffffff871ac536 RDI: 00000000ffffffff
 RBP: ffffae46807a3a10 R08: 0000000000000000 R09: c0000000ffff7fff
 R10: 0000000000000001 R11: ffffae46807a36a8 R12: ffff8e028404b800
 R13: ffff8e028404bd30 R14: dead000000000100 R15: ffff8e02fafa2400
 FS:  00007efdc92e4480(0000) GS:ffff8e02fb600000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000682f48 CR3: 00000001058be000 CR4: 0000000000350ef0
 Kernel panic - not syncing: Fatal exception in interrupt
 Kernel Offset: 0x4e00000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
 ---[ end Kernel panic - not syncing: Fatal exception in interrupt ]---

we can remove 'q->classes[i].alist' only if DRR class 'i' was part of the
active list. In the ETS scheduler DRR classes belong to that list only if
the queue length is greater than zero: we need to test for non-zero value
of 'q->classes[i].qdisc->q.qlen' before removing from the list, similarly
to what has been done elsewhere in the ETS code.

Fixes: de6d25924c2a ("net/sched: sch_ets: don't peek at classes beyond 'nbands'")
Reported-by: Shuang Li <shuali@redhat.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-12-22 09:30:54 +01:00
arch s390/kexec_file: fix error handling when applying relocations 2021-12-22 09:30:53 +01:00
block block: fix ioprio_get(IOPRIO_WHO_PGRP) vs setuid(2) 2021-12-14 11:32:40 +01:00
certs certs: Trigger creation of RSA module signing key if it's not an RSA key 2021-09-15 09:50:29 +02:00
crypto crypto: pcrypt - Delay write to padata->info 2021-11-18 14:04:12 +01:00
Documentation Documentation/Kbuild: Remove references to gcc-plugin.sh 2021-12-14 11:32:46 +01:00
drivers dmaengine: st_fdma: fix MODULE_ALIAS 2021-12-22 09:30:53 +01:00
fs ceph: initialize pathlen variable in reconnect_caps_cb 2021-12-22 09:30:52 +01:00
include PM: runtime: Fix pm_runtime_active() kerneldoc comment 2021-12-14 11:32:41 +01:00
init bootconfig: init: Fix memblock leak in xbc_make_cmdline() 2021-11-21 13:46:35 +01:00
ipc shm: extend forced shm destroy to support objects from several IPC nses 2021-12-01 09:19:10 +01:00
kernel audit: improve robustness of the audit queue handling 2021-12-22 09:30:51 +01:00
lib siphash: use _unaligned version by default 2021-12-08 09:03:23 +01:00
LICENSES LICENSES/deprecated: add Zlib license text 2020-09-16 14:33:49 +02:00
mm memblock: ensure there is no overflow in memblock_overlaps_region() 2021-12-17 10:14:42 +01:00
net net/sched: sch_ets: don't remove idle classes from the round-robin list 2021-12-22 09:30:54 +01:00
samples samples/kretprobes: Fix return value if register_kretprobe() failed 2021-11-18 14:04:11 +01:00
scripts recordmcount.pl: look for jgnop instruction as well as bcrl on s390 2021-12-22 09:30:51 +01:00
security selinux: fix NULL-pointer dereference when hashtab allocation fails 2021-11-26 10:39:21 +01:00
sound ALSA: hda/hdmi: fix HDA codec entry table order for ADL-P 2021-12-17 10:14:40 +01:00
tools selftests: Fix IPv6 address bind tests 2021-12-22 09:30:53 +01:00
usr
virt KVM: downgrade two BUG_ONs to WARN_ON_ONCE 2021-12-22 09:30:50 +01:00
.clang-format RDMA 5.10 pull request 2020-10-17 11:18:18 -07:00
.cocciconfig
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.mailmap mailmap: add two more addresses of Uwe Kleine-König 2020-12-06 10:19:07 -08:00
COPYING
CREDITS MAINTAINERS: Move Jason Cooper to CREDITS 2020-11-30 10:20:34 +01:00
Kbuild
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MAINTAINERS MAINTAINERS: adjust GCC PLUGINS after gcc-plugin.sh removal 2021-12-14 11:32:46 +01:00
Makefile Linux 5.10.87 2021-12-17 10:14:42 +01:00
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