Commit Graph

11 Commits

Author SHA1 Message Date
Zhengchao Shao
34f2a4eedc net: sched: delete duplicate cleanup of backlog and qlen
[ Upstream commit c19d893fbf ]

qdisc_reset() is clearing qdisc->q.qlen and qdisc->qstats.backlog
_after_ calling qdisc->ops->reset. There is no need to clear them
again in the specific reset function.

Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com>
Link: https://lore.kernel.org/r/20220824005231.345727-1-shaozhengchao@huawei.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Stable-dep-of: 2a3fc78210 ("net: sched: sfb: fix null pointer access issue when sfb_init() fails")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-29 10:12:57 +02:00
Davide Caratti
491c125344 net/sched: sch_ets: don't remove idle classes from the round-robin list
[ Upstream commit c062f2a0b0 ]

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: de6d25924c ("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 09:32:41 +01:00
Davide Caratti
e25bdbc7e9 net/sched: sch_ets: don't peek at classes beyond 'nbands'
[ Upstream commit de6d25924c ]

when the number of DRR classes decreases, the round-robin active list can
contain elements that have already been freed in ets_qdisc_change(). As a
consequence, it's possible to see a NULL dereference crash, caused by the
attempt to call cl->qdisc->ops->peek(cl->qdisc) when cl->qdisc is NULL:

 BUG: kernel NULL pointer dereference, address: 0000000000000018
 #PF: supervisor read access in kernel mode
 #PF: error_code(0x0000) - not-present page
 PGD 0 P4D 0
 Oops: 0000 [#1] PREEMPT SMP NOPTI
 CPU: 1 PID: 910 Comm: mausezahn Not tainted 5.16.0-rc1+ #475
 Hardware name: Red Hat KVM, BIOS 1.11.1-4.module+el8.1.0+4066+0f1aadab 04/01/2014
 RIP: 0010:ets_qdisc_dequeue+0x129/0x2c0 [sch_ets]
 Code: c5 01 41 39 ad e4 02 00 00 0f 87 18 ff ff ff 49 8b 85 c0 02 00 00 49 39 c4 0f 84 ba 00 00 00 49 8b ad c0 02 00 00 48 8b 7d 10 <48> 8b 47 18 48 8b 40 38 0f ae e8 ff d0 48 89 c3 48 85 c0 0f 84 9d
 RSP: 0000:ffffbb36c0b5fdd8 EFLAGS: 00010287
 RAX: ffff956678efed30 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 0000000000000002 RSI: ffffffff9b938dc9 RDI: 0000000000000000
 RBP: ffff956678efed30 R08: e2f3207fe360129c R09: 0000000000000000
 R10: 0000000000000001 R11: 0000000000000001 R12: ffff956678efeac0
 R13: ffff956678efe800 R14: ffff956611545000 R15: ffff95667ac8f100
 FS:  00007f2aa9120740(0000) GS:ffff95667b800000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000000018 CR3: 000000011070c000 CR4: 0000000000350ee0
 Call Trace:
  <TASK>
  qdisc_peek_dequeued+0x29/0x70 [sch_ets]
  tbf_dequeue+0x22/0x260 [sch_tbf]
  __qdisc_run+0x7f/0x630
  net_tx_action+0x290/0x4c0
  __do_softirq+0xee/0x4f8
  irq_exit_rcu+0xf4/0x130
  sysvec_apic_timer_interrupt+0x52/0xc0
  asm_sysvec_apic_timer_interrupt+0x12/0x20
 RIP: 0033:0x7f2aa7fc9ad4
 Code: b9 ff ff 48 8b 54 24 18 48 83 c4 08 48 89 ee 48 89 df 5b 5d e9 ed fc ff ff 0f 1f 00 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa <53> 48 83 ec 10 48 8b 05 10 64 33 00 48 8b 00 48 85 c0 0f 85 84 00
 RSP: 002b:00007ffe5d33fab8 EFLAGS: 00000202
 RAX: 0000000000000002 RBX: 0000561f72c31460 RCX: 0000561f72c31720
 RDX: 0000000000000002 RSI: 0000561f72c31722 RDI: 0000561f72c31720
 RBP: 000000000000002a R08: 00007ffe5d33fa40 R09: 0000000000000014
 R10: 0000000000000000 R11: 0000000000000246 R12: 0000561f7187e380
 R13: 0000000000000000 R14: 0000000000000000 R15: 0000561f72c31460
  </TASK>
 Modules linked in: sch_ets sch_tbf dummy rfkill iTCO_wdt intel_rapl_msr iTCO_vendor_support intel_rapl_common joydev virtio_balloon lpc_ich i2c_i801 i2c_smbus pcspkr ip_tables xfs libcrc32c crct10dif_pclmul crc32_pclmul crc32c_intel ahci libahci ghash_clmulni_intel serio_raw libata virtio_blk virtio_console virtio_net net_failover failover sunrpc dm_mirror dm_region_hash dm_log dm_mod
 CR2: 0000000000000018

Ensuring that 'alist' was never zeroed [1] was not sufficient, we need to
remove from the active list those elements that are no more SP nor DRR.

[1] https://lore.kernel.org/netdev/60d274838bf09777f0371253416e8af71360bc08.1633609148.git.dcaratti@redhat.com/

v3: fix race between ets_qdisc_change() and ets_qdisc_dequeue() delisting
    DRR classes beyond 'nbands' in ets_qdisc_change() with the qdisc lock
    acquired, thanks to Cong Wang.

v2: when a NULL qdisc is found in the DRR active list, try to dequeue skb
    from the next list item.

Reported-by: Hangbin Liu <liuhangbin@gmail.com>
Fixes: dcc68b4d80 ("net: sch_ets: Add a new Qdisc")
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Link: https://lore.kernel.org/r/7a5c496eed2d62241620bdbb83eb03fb9d571c99.1637762721.git.dcaratti@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-12-01 09:04:53 +01:00
Jakub Kicinski
97c78d0af5 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
drivers/net/wwan/mhi_wwan_mbim.c - drop the extra arg.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-08-26 17:57:57 -07:00
Davide Caratti
cd9b50adc6 net/sched: ets: fix crash when flipping from 'strict' to 'quantum'
While running kselftests, Hangbin observed that sch_ets.sh often crashes,
and splats like the following one are seen in the output of 'dmesg':

 BUG: kernel NULL pointer dereference, address: 0000000000000000
 #PF: supervisor read access in kernel mode
 #PF: error_code(0x0000) - not-present page
 PGD 159f12067 P4D 159f12067 PUD 159f13067 PMD 0
 Oops: 0000 [#1] SMP NOPTI
 CPU: 2 PID: 921 Comm: tc Not tainted 5.14.0-rc6+ #458
 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+0x2d/0x50
 Code: 48 8b 57 08 48 b9 00 01 00 00 00 00 ad de 48 39 c8 0f 84 ac 6e 5b 00 48 b9 22 01 00 00 00 00 ad de 48 39 ca 0f 84 cf 6e 5b 00 <48> 8b 32 48 39 fe 0f 85 af 6e 5b 00 48 8b 50 08 48 39 f2 0f 85 94
 RSP: 0018:ffffb2da005c3890 EFLAGS: 00010217
 RAX: 0000000000000000 RBX: ffff9073ba23f800 RCX: dead000000000122
 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff9073ba23fbc8
 RBP: ffff9073ba23f890 R08: 0000000000000001 R09: 0000000000000001
 R10: 0000000000000001 R11: 0000000000000001 R12: dead000000000100
 R13: ffff9073ba23fb00 R14: 0000000000000002 R15: 0000000000000002
 FS:  00007f93e5564e40(0000) GS:ffff9073bba00000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000000000 CR3: 000000014ad34000 CR4: 0000000000350ee0
 Call Trace:
  ets_qdisc_reset+0x6e/0x100 [sch_ets]
  qdisc_reset+0x49/0x1d0
  tbf_reset+0x15/0x60 [sch_tbf]
  qdisc_reset+0x49/0x1d0
  dev_reset_queue.constprop.42+0x2f/0x90
  dev_deactivate_many+0x1d3/0x3d0
  dev_deactivate+0x56/0x90
  qdisc_graft+0x47e/0x5a0
  tc_get_qdisc+0x1db/0x3e0
  rtnetlink_rcv_msg+0x164/0x4c0
  netlink_rcv_skb+0x50/0x100
  netlink_unicast+0x1a5/0x280
  netlink_sendmsg+0x242/0x480
  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: 0033:0x7f93e44b8338
 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:00007ffc0db737a8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
 RAX: ffffffffffffffda RBX: 0000000061255c06 RCX: 00007f93e44b8338
 RDX: 0000000000000000 RSI: 00007ffc0db73810 RDI: 0000000000000003
 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
 R10: 000000000000000b R11: 0000000000000246 R12: 0000000000000001
 R13: 0000000000687880 R14: 0000000000000000 R15: 0000000000000000
 Modules linked in: sch_ets sch_tbf dummy rfkill iTCO_wdt iTCO_vendor_support intel_rapl_msr intel_rapl_common joydev i2c_i801 pcspkr i2c_smbus lpc_ich virtio_balloon ip_tables xfs libcrc32c crct10dif_pclmul crc32_pclmul crc32c_intel ahci libahci ghash_clmulni_intel libata serio_raw virtio_blk virtio_console virtio_net net_failover failover sunrpc dm_mirror dm_region_hash dm_log dm_mod
 CR2: 0000000000000000

When the change() function decreases the value of 'nstrict', we must take
into account that packets might be already enqueued on a class that flips
from 'strict' to 'quantum': otherwise that class will not be added to the
bandwidth-sharing list. Then, a call to ets_qdisc_reset() will attempt to
do list_del(&alist) with 'alist' filled with zero, hence the NULL pointer
dereference.
For classes flipping from 'strict' to 'quantum', initialize an empty list
and eventually add it to the bandwidth-sharing list, if there are packets
already enqueued. In this way, the kernel will:
 a) prevent crashing as described above.
 b) avoid retaining the backlog packets (for an arbitrarily long time) in
    case no packet is enqueued after a change from 'strict' to 'quantum'.

Reported-by: Hangbin Liu <liuhangbin@gmail.com>
Fixes: dcc68b4d80 ("net: sch_ets: Add a new Qdisc")
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-25 11:15:30 +01:00
Davide Caratti
3aa2605594 net/sched: store the last executed chain also for clsact egress
currently, only 'ingress' and 'clsact ingress' qdiscs store the tc 'chain
id' in the skb extension. However, userspace programs (like ovs) are able
to setup egress rules, and datapath gets confused in case it doesn't find
the 'chain id' for a packet that's "recirculated" by tc.
Change tcf_classify() to have the same semantic as tcf_classify_ingress()
so that a single function can be called in ingress / egress, using the tc
ingress / egress block respectively.

Suggested-by: Alaa Hleilel <alaa@nvidia.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29 22:17:37 +01:00
Petr Machata
ac5c66f261 Revert "net: sched: Pass root lock to Qdisc_ops.enqueue"
This reverts commit aebe4426cc.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-07-16 16:48:34 -07:00
Gustavo A. R. Silva
964201de69 net/sched: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-07 15:47:46 -07:00
Petr Machata
aebe4426cc net: sched: Pass root lock to Qdisc_ops.enqueue
A following patch introduces qevents, points in qdisc algorithm where
packet can be processed by user-defined filters. Should this processing
lead to a situation where a new packet is to be enqueued on the same port,
holding the root lock would lead to deadlocks. To solve the issue, qevent
handler needs to unlock and relock the root lock when necessary.

To that end, add the root lock argument to the qdisc op enqueue, and
propagate throughout.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-29 17:08:28 -07:00
Petr Machata
d35eb52bd2 net: sch_ets: Make the ETS qdisc offloadable
Add hooks at appropriate points to make it possible to offload the ETS
Qdisc.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-12-18 13:32:29 -08:00
Petr Machata
dcc68b4d80 net: sch_ets: Add a new Qdisc
Introduces a new Qdisc, which is based on 802.1Q-2014 wording. It is
PRIO-like in how it is configured, meaning one needs to specify how many
bands there are, how many are strict and how many are dwrr, quanta for the
latter, and priomap.

The new Qdisc operates like the PRIO / DRR combo would when configured as
per the standard. The strict classes, if any, are tried for traffic first.
When there's no traffic in any of the strict queues, the ETS ones (if any)
are treated in the same way as in DRR.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-12-18 13:32:29 -08:00