Commit Graph

235 Commits

Author SHA1 Message Date
Rahul Rameshbabu a22b7388d6 sch_htb: Avoid grafting on htb_destroy_class_offload when destroying htb
Peek at old qdisc and graft only when deleting a leaf class in the htb,
rather than when deleting the htb itself. Do not peek at the qdisc of the
netdev queue when destroying the htb. The caller may already have grafted a
new qdisc that is not part of the htb structure being destroyed.

This fix resolves two use cases.

  1. Using tc to destroy the htb.
    - Netdev was being prematurely activated before the htb was fully
      destroyed.
  2. Using tc to replace the htb with another qdisc (which also leads to
     the htb being destroyed).
    - Premature netdev activation like previous case. Newly grafted qdisc
      was also getting accidentally overwritten when destroying the htb.

Fixes: d03b195b5a ("sch_htb: Hierarchical QoS hardware offload")
Signed-off-by: Rahul Rameshbabu <rrameshbabu@nvidia.com>
Reviewed-by: Saeed Mahameed <saeedm@nvidia.com>
Reviewed-by: Maxim Mikityanskiy <maxtram95@gmail.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Link: https://lore.kernel.org/r/20230113005528.302625-1-rrameshbabu@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-13 22:14:25 -08:00
Randy Dunlap 43d253781f net: sched: htb: fix htb_classify() kernel-doc
Fix W=1 kernel-doc warning:

net/sched/sch_htb.c:214: warning: expecting prototype for htb_classify(). Prototype was for HTB_DIRECT() instead

by moving the HTB_DIRECT() macro above the function.
Add kernel-doc notation for function parameters as well.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-01-02 13:34:48 +00:00
Zhengchao Shao e046fa895c net/sched: use tc_qdisc_stats_dump() in qdisc
use tc_qdisc_stats_dump() in qdisc.

Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com>
Reviewed-by: Victor Nogueira <victor@mojatatu.com>
Tested-by: Victor Nogueira <victor@mojatatu.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-09-22 17:34:10 -07:00
Zhengchao Shao d59f4e1d1f net: sched: htb: remove redundant resource cleanup in htb_init()
If htb_init() fails, qdisc_create() invokes htb_destroy() to clear
resources. Therefore, remove redundant resource cleanup in htb_init().

Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-09-03 10:40:40 +01:00
Zhengchao Shao 44387d1736 net: sched: remove unnecessary init of qdisc skb head
The memory allocated by using kzallloc_node and kcalloc has been cleared.
Therefore, the structure members of the new qdisc are 0. So there's no
need to explicitly assign a value of 0.

Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-08-26 12:03:04 +01:00
Zhengchao Shao c19d893fbf net: sched: delete duplicate cleanup of backlog and qlen
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>
2022-08-25 15:10:17 +02:00
Maxim Mikityanskiy 429c3be8a5 sch_htb: Fail on unsupported parameters when offload is requested
The current implementation of HTB offload doesn't support some
parameters. Instead of ignoring them, actively return the EINVAL error
when they are set to non-defaults.

As this patch goes to stable, the driver API is not changed here. If
future drivers support more offload parameters, the checks can be moved
to the driver side.

Note that the buffer and cbuffer parameters are also not supported, but
the tc userspace tool assigns some default values derived from rate and
ceil, and identifying these defaults in sch_htb would be unreliable, so
they are still ignored.

Fixes: d03b195b5a ("sch_htb: Hierarchical QoS hardware offload")
Reported-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Maxim Mikityanskiy <maximmi@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://lore.kernel.org/r/20220125100654.424570-1-maximmi@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-01-25 20:00:02 -08:00
Maxim Mikityanskiy 648a991cf3 sch_htb: Add extack messages for EOPNOTSUPP errors
In order to make the "Operation not supported" message clearer to the
user, add extack messages explaining why exactly adding offloaded HTB
could be not supported in each case.

Signed-off-by: Maxim Mikityanskiy <maximmi@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-28 14:34:03 +01:00
Ahmed S. Darwish 29cbcd8582 net: sched: Remove Qdisc::running sequence counter
The Qdisc::running sequence counter has two uses:

  1. Reliably reading qdisc's tc statistics while the qdisc is running
     (a seqcount read/retry loop at gnet_stats_add_basic()).

  2. As a flag, indicating whether the qdisc in question is running
     (without any retry loops).

For the first usage, the Qdisc::running sequence counter write section,
qdisc_run_begin() => qdisc_run_end(), covers a much wider area than what
is actually needed: the raw qdisc's bstats update. A u64_stats sync
point was thus introduced (in previous commits) inside the bstats
structure itself. A local u64_stats write section is then started and
stopped for the bstats updates.

Use that u64_stats sync point mechanism for the bstats read/retry loop
at gnet_stats_add_basic().

For the second qdisc->running usage, a __QDISC_STATE_RUNNING bit flag,
accessed with atomic bitops, is sufficient. Using a bit flag instead of
a sequence counter at qdisc_run_begin/end() and qdisc_is_running() leads
to the SMP barriers implicitly added through raw_read_seqcount() and
write_seqcount_begin/end() getting removed. All call sites have been
surveyed though, and no required ordering was identified.

Now that the qdisc->running sequence counter is no longer used, remove
it.

Note, using u64_stats implies no sequence counter protection for 64-bit
architectures. This can lead to the qdisc tc statistics "packets" vs.
"bytes" values getting out of sync on rare occasions. The individual
values will still be valid.

Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-18 12:54:41 +01:00
Ahmed S. Darwish 50dc9a8572 net: sched: Merge Qdisc::bstats and Qdisc::cpu_bstats data types
The only factor differentiating per-CPU bstats data type (struct
gnet_stats_basic_cpu) from the packed non-per-CPU one (struct
gnet_stats_basic_packed) was a u64_stats sync point inside the former.
The two data types are now equivalent: earlier commits added a u64_stats
sync point to the latter.

Combine both data types into "struct gnet_stats_basic_sync". This
eliminates redundancy and simplifies the bstats read/write APIs.

Use u64_stats_t for bstats "packets" and "bytes" data types. On 64-bit
architectures, u64_stats sync points do not use sequence counter
protection.

Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-18 12:54:41 +01:00
Ahmed S. Darwish f56940daa5 net: sched: Use _bstats_update/set() instead of raw writes
The Qdisc::running sequence counter, used to protect Qdisc::bstats reads
from parallel writes, is in the process of being removed. Qdisc::bstats
read/writes will synchronize using an internal u64_stats sync point
instead.

Modify all bstats writes to use _bstats_update(). This ensures that
the internal u64_stats sync point is always acquired and released as
appropriate.

Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-18 12:54:41 +01:00
Ahmed S. Darwish 67c9e6270f net: sched: Protect Qdisc::bstats with u64_stats
The not-per-CPU variant of qdisc tc (traffic control) statistics,
Qdisc::gnet_stats_basic_packed bstats, is protected with Qdisc::running
sequence counter.

This sequence counter is used for reliably protecting bstats reads from
parallel writes. Meanwhile, the seqcount's write section covers a much
wider area than bstats update: qdisc_run_begin() => qdisc_run_end().

That read/write section asymmetry can lead to needless retries of the
read section. To prepare for removing the Qdisc::running sequence
counter altogether, introduce a u64_stats sync point inside bstats
instead.

Modify _bstats_update() to start/end the bstats u64_stats write
section.

For bisectability, and finer commits granularity, the bstats read
section is still protected with a Qdisc::running read/retry loop and
qdisc_run_begin/end() still starts/ends that seqcount write section.
Once all call sites are modified to use _bstats_update(), the
Qdisc::running seqcount will be removed and bstats read/retry loop will
be modified to utilize the internal u64_stats sync point.

Note, using u64_stats implies no sequence counter protection for 64-bit
architectures. This can lead to the statistics "packets" vs. "bytes"
values getting out of sync on rare occasions. The individual values will
still be valid.

[bigeasy: Minor commit message edits, init all gnet_stats_basic_packed.]

Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-18 12:54:41 +01:00
Maxim Mikityanskiy ca49bfd90a sch_htb: Fix inconsistency when leaf qdisc creation fails
In HTB offload mode, qdiscs of leaf classes are grafted to netdev
queues. sch_htb expects the dev_queue field of these qdiscs to point to
the corresponding queues. However, qdisc creation may fail, and in that
case noop_qdisc is used instead. Its dev_queue doesn't point to the
right queue, so sch_htb can lose track of used netdev queues, which will
cause internal inconsistencies.

This commit fixes this bug by keeping track of the netdev queue inside
struct htb_class. All reads of cl->leaf.q->dev_queue are replaced by the
new field, the two values are synced on writes, and WARNs are added to
assert equality of the two values.

The driver API has changed: when TC_HTB_LEAF_DEL needs to move a queue,
the driver used to pass the old and new queue IDs to sch_htb. Now that
there is a new field (offload_queue) in struct htb_class that needs to
be updated on this operation, the driver will pass the old class ID to
sch_htb instead (it already knows the new class ID).

Fixes: d03b195b5a ("sch_htb: Hierarchical QoS hardware offload")
Signed-off-by: Maxim Mikityanskiy <maximmi@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://lore.kernel.org/r/20210826115425.1744053-1-maximmi@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-08-30 16:33:59 -07:00
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
David S. Miller 126285651b Merge ra.kernel.org:/pub/scm/linux/kernel/git/netdev/net
Bug fixes overlapping feature additions and refactoring, mostly.

Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-07 13:01:52 -07:00
Yu Kuai 9977d6f56b sch_htb: fix doc warning in htb_lookup_leaf()
Add description for parameters of htb_lookup_leaf()
to fix gcc W=1 warnings:

net/sched/sch_htb.c:773: warning: Function parameter or member 'hprio' not described in 'htb_lookup_leaf'
net/sched/sch_htb.c:773: warning: Function parameter or member 'prio' not described in 'htb_lookup_leaf'

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-07 12:28:41 -07:00
Yu Kuai 2c3ee53ea6 sch_htb: fix doc warning in htb_do_events()
Add description for parameters of htb_do_events()
to fix gcc W=1 warnings:

net/sched/sch_htb.c:708: warning: Function parameter or member 'q' not described in 'htb_do_events'
net/sched/sch_htb.c:708: warning: Function parameter or member 'level' not described in 'htb_do_events'
net/sched/sch_htb.c:708: warning: Function parameter or member 'start' not described in 'htb_do_events'

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-07 12:28:41 -07:00
Yu Kuai 0e5c90848a sch_htb: fix doc warning in htb_charge_class()
Add description for parameters of htb_charge_class()
to fix gcc W=1 warnings:

net/sched/sch_htb.c:663: warning: Function parameter or member 'q' not described in 'htb_charge_class'
net/sched/sch_htb.c:663: warning: Function parameter or member 'cl' not described in 'htb_charge_class'
net/sched/sch_htb.c:663: warning: Function parameter or member 'level' not described in 'htb_charge_class'
net/sched/sch_htb.c:663: warning: Function parameter or member 'skb' not described in 'htb_charge_class'

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-07 12:28:41 -07:00
Yu Kuai 9a034f25e4 sch_htb: fix doc warning in htb_deactivate()
Add description for parameters of htb_deactivate()
to fix gcc W=1 warnings:

net/sched/sch_htb.c:578: warning: Function parameter or member 'q' not described in 'htb_deactivate'
net/sched/sch_htb.c:578: warning: Function parameter or member 'cl' not described in 'htb_deactivate'

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-07 12:28:41 -07:00
Yu Kuai 8df7e8fff8 sch_htb: fix doc warning in htb_activate()
Add description for parameters of htb_activate()
to fix gcc W=1 warnings:

net/sched/sch_htb.c:562: warning: Function parameter or member 'q' not described in 'htb_activate'
net/sched/sch_htb.c:562: warning: Function parameter or member 'cl' not described in 'htb_activate'

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-07 12:28:41 -07:00
Yu Kuai 4b479e9883 sch_htb: fix doc warning in htb_change_class_mode()
Add description for parameters of htb_change_class_mode()
to fix gcc W=1 warnings:

net/sched/sch_htb.c:533: warning: Function parameter or member 'q' not described in 'htb_change_class_mode'
net/sched/sch_htb.c:533: warning: Function parameter or member 'cl' not described in 'htb_change_class_mode'
net/sched/sch_htb.c:533: warning: Function parameter or member 'diff' not described in 'htb_change_class_mode'

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-07 12:28:40 -07:00
Yu Kuai 1e9559527a sch_htb: fix doc warning in htb_class_mode()
Add description for parameters of htb_class_mode()
to fix gcc W=1 warnings:

net/sched/sch_htb.c:507: warning: Function parameter or member 'cl' not described in 'htb_class_mode'
net/sched/sch_htb.c:507: warning: Function parameter or member 'diff' not described in 'htb_class_mode'

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-07 12:28:40 -07:00
Yu Kuai 4113be2020 sch_htb: fix doc warning in htb_deactivate_prios()
Add description for parameters of htb_deactivate_prios()
to fix gcc W=1 warnings:

net/sched/sch_htb.c:442: warning: Function parameter or member 'q' not described in 'htb_deactivate_prios'
net/sched/sch_htb.c:442: warning: Function parameter or member 'cl' not described in 'htb_deactivate_prios'

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-07 12:28:40 -07:00
Yu Kuai 876b5fc0c0 sch_htb: fix doc warning in htb_activate_prios()
Add description for parameters of htb_activate_prios()
to fix gcc W=1 warnings:

net/sched/sch_htb.c:407: warning: Function parameter or member 'q' not described in 'htb_activate_prios'
net/sched/sch_htb.c:407: warning: Function parameter or member 'cl' not described in 'htb_activate_prios'

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-07 12:28:40 -07:00
Yu Kuai 5f8c6d05f3 sch_htb: fix doc warning in htb_remove_class_from_row()
Add description for parameters of htb_remove_class_from_row()
to fix gcc W=1 warnings:

net/sched/sch_htb.c:380: warning: Function parameter or member 'q' not described in 'htb_remove_class_from_row'
net/sched/sch_htb.c:380: warning: Function parameter or member 'cl' not described in 'htb_remove_class_from_row'
net/sched/sch_htb.c:380: warning: Function parameter or member 'mask' not described in 'htb_remove_class_from_row'

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-07 12:28:40 -07:00
Yu Kuai 996bccc39a sch_htb: fix doc warning in htb_add_class_to_row()
Add description for parameters of htb_add_class_to_row() to fix
gcc W=1 warnings:

net/sched/sch_htb.c:351: warning: Function parameter or member 'q' not described in 'htb_add_class_to_row'
net/sched/sch_htb.c:351: warning: Function parameter or member 'cl' not described in 'htb_add_class_to_row'
net/sched/sch_htb.c:351: warning: Function parameter or member 'mask' not described in 'htb_add_class_to_row'

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-07 12:28:40 -07:00
Yu Kuai 274e5d0e55 sch_htb: fix doc warning in htb_next_rb_node()
Add description for parameters of htb_next_rb_node() to fix
gcc W=1 warnings:

net/sched/sch_htb.c:339: warning: Function parameter or member 'n' not described in 'htb_next_rb_node'

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-07 12:28:40 -07:00
Yu Kuai 4d7efa73fa sch_htb: fix doc warning in htb_add_to_wait_tree()
Add description for parameters of htb_add_to_wait_tree() to fix
gcc W=1 warnings:

net/sched/sch_htb.c:308: warning: Function parameter or member 'q' not described in 'htb_add_to_wait_tree'
net/sched/sch_htb.c:308: warning: Function parameter or member 'cl' not described in 'htb_add_to_wait_tree'
net/sched/sch_htb.c:308: warning: Function parameter or member 'delay' not described in 'htb_add_to_wait_tree'

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-07 12:28:40 -07:00
Yunjian Wang 944d671d5f sch_htb: fix refcount leak in htb_parent_to_leaf_offload
The commit ae81feb733 ("sch_htb: fix null pointer dereference
on a null new_q") fixes a NULL pointer dereference bug, but it
is not correct.

Because htb_graft_helper properly handles the case when new_q
is NULL, and after the previous patch by skipping this call
which creates an inconsistency : dev_queue->qdisc will still
point to the old qdisc, but cl->parent->leaf.q will point to
the new one (which will be noop_qdisc, because new_q was NULL).
The code is based on an assumption that these two pointers are
the same, so it can lead to refcount leaks.

The correct fix is to add a NULL pointer check to protect
qdisc_refcount_inc inside htb_parent_to_leaf_offload.

Fixes: ae81feb733 ("sch_htb: fix null pointer dereference on a null new_q")
Signed-off-by: Yunjian Wang <wangyunjian@huawei.com>
Suggested-by: Maxim Mikityanskiy <maximmi@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-04 14:44:18 -07:00
Yu Kuai a10541f5d9 sch_htb: fix doc warning in htb_add_to_id_tree()
Add description for parameters of htb_add_to_id_tree() to fix
gcc W=1 warnings:
net/sched/sch_htb.c:282: warning: Function parameter or member 'root' not described in 'htb_add_to_id_tree'
net/sched/sch_htb.c:282: warning: Function parameter or member 'cl' not described in 'htb_add_to_id_tree'
net/sched/sch_htb.c:282: warning: Function parameter or member 'prio' not described in 'htb_add_to_id_tree'

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-03 15:26:32 -07:00
Zheng Yongjun 37f2ad2b90 net: sched: Fix spelling mistakes
Fix some spelling mistakes in comments:
sevaral  ==> several
sugestion  ==> suggestion
unregster  ==> unregister
suplied  ==> supplied
cirsumstances  ==> circumstances

Signed-off-by: Zheng Yongjun <zhengyongjun3@huawei.com>
Link: https://lore.kernel.org/r/20210531020048.2920054-1-zhengyongjun3@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-05-31 22:44:56 -07:00
Yunjian Wang ae81feb733 sch_htb: fix null pointer dereference on a null new_q
sch_htb: fix null pointer dereference on a null new_q

Currently if new_q is null, the null new_q pointer will be
dereference when 'q->offload' is true. Fix this by adding
a braces around htb_parent_to_leaf_offload() to avoid it.

Addresses-Coverity: ("Dereference after null check")
Fixes: d03b195b5a ("sch_htb: Hierarchical QoS hardware offload")

Signed-off-by: Yunjian Wang <wangyunjian@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-30 13:50:03 -07:00
Maxim Mikityanskiy fb3a3e37de sch_htb: Fix offload cleanup in htb_destroy on htb_init failure
htb_init may fail to do the offload if it's not supported or if a
runtime error happens when allocating direct qdiscs. In those cases
TC_HTB_CREATE command is not sent to the driver, however, htb_destroy
gets called anyway and attempts to send TC_HTB_DESTROY.

It shouldn't happen, because the driver didn't receive TC_HTB_CREATE,
and also because the driver may not support ndo_setup_tc at all, while
q->offload is true, and htb_destroy mistakenly thinks the offload is
supported. Trying to call ndo_setup_tc in the latter case will lead to a
NULL pointer dereference.

This commit fixes the issues with htb_destroy by deferring assignment of
q->offload until after the TC_HTB_CREATE command. The necessary cleanup
of the offload entities is already done in htb_init.

Reported-by: syzbot+b53a709f04722ca12a3c@syzkaller.appspotmail.com
Fixes: d03b195b5a ("sch_htb: Hierarchical QoS hardware offload")
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Maxim Mikityanskiy <maximmi@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-11 18:30:32 -08:00
Maxim Mikityanskiy 93bde210c4 sch_htb: Fix select_queue for non-offload mode
htb_select_queue assumes it's always the offload mode, and it ends up in
calling ndo_setup_tc without any checks. It may lead to a NULL pointer
dereference if ndo_setup_tc is not implemented, or to an error returned
from the driver, which will prevent attaching qdiscs to HTB classes in
the non-offload mode.

This commit fixes the bug by adding the missing check to
htb_select_queue. In the non-offload mode it will return sch->dev_queue,
mimicking tc_modify_qdisc's behavior for the case where select_queue is
not implemented.

Reported-by: syzbot+b53a709f04722ca12a3c@syzkaller.appspotmail.com
Fixes: d03b195b5a ("sch_htb: Hierarchical QoS hardware offload")
Signed-off-by: Maxim Mikityanskiy <maximmi@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-11 18:30:32 -08:00
Maxim Mikityanskiy 8327158624 sch_htb: Stats for offloaded HTB
This commit adds support for statistics of offloaded HTB. Bytes and
packets counters for leaf and inner nodes are supported, the values are
taken from per-queue qdiscs, and the numbers that the user sees should
have the same behavior as the software (non-offloaded) HTB.

Signed-off-by: Maxim Mikityanskiy <maximmi@mellanox.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-22 20:41:29 -08:00
Maxim Mikityanskiy d03b195b5a sch_htb: Hierarchical QoS hardware offload
HTB doesn't scale well because of contention on a single lock, and it
also consumes CPU. This patch adds support for offloading HTB to
hardware that supports hierarchical rate limiting.

In the offload mode, HTB passes control commands to the driver using
ndo_setup_tc. The driver has to replicate the whole hierarchy of classes
and their settings (rate, ceil) in the NIC. Every modification of the
HTB tree caused by the admin results in ndo_setup_tc being called.

After this setup, the HTB algorithm is done completely in the NIC. An SQ
(send queue) is created for every leaf class and attached to the
hierarchy, so that the NIC can calculate and obey aggregated rate
limits, too. In the future, it can be changed, so that multiple SQs will
back a single leaf class.

ndo_select_queue is responsible for selecting the right queue that
serves the traffic class of each packet.

The data path works as follows: a packet is classified by clsact, the
driver selects a hardware queue according to its class, and the packet
is enqueued into this queue's qdisc.

This solution addresses two main problems of scaling HTB:

1. Contention by flow classification. Currently the filters are attached
to the HTB instance as follows:

    # tc filter add dev eth0 parent 1:0 protocol ip flower dst_port 80
    classid 1:10

It's possible to move classification to clsact egress hook, which is
thread-safe and lock-free:

    # tc filter add dev eth0 egress protocol ip flower dst_port 80
    action skbedit priority 1:10

This way classification still happens in software, but the lock
contention is eliminated, and it happens before selecting the TX queue,
allowing the driver to translate the class to the corresponding hardware
queue in ndo_select_queue.

Note that this is already compatible with non-offloaded HTB and doesn't
require changes to the kernel nor iproute2.

2. Contention by handling packets. HTB is not multi-queue, it attaches
to a whole net device, and handling of all packets takes the same lock.
When HTB is offloaded, it registers itself as a multi-queue qdisc,
similarly to mq: HTB is attached to the netdev, and each queue has its
own qdisc.

Some features of HTB may be not supported by some particular hardware,
for example, the maximum number of classes may be limited, the
granularity of rate and ceil parameters may be different, etc. - so, the
offload is not enabled by default, a new parameter is used to enable it:

    # tc qdisc replace dev eth0 root handle 1: htb offload

Signed-off-by: Maxim Mikityanskiy <maximmi@mellanox.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-22 20:41:29 -08:00
Maxim Mikityanskiy 4dd78a7373 net: sched: Add extack to Qdisc_class_ops.delete
In a following commit, sch_htb will start using extack in the delete
class operation to pass hardware errors in offload mode. This commit
prepares for that by adding the extack parameter to this callback and
converting usage of the existing qdiscs.

Signed-off-by: Maxim Mikityanskiy <maximmi@mellanox.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-22 20:41:29 -08:00
Linus Torvalds 47ec5303d7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from David Miller:

 1) Support 6Ghz band in ath11k driver, from Rajkumar Manoharan.

 2) Support UDP segmentation in code TSO code, from Eric Dumazet.

 3) Allow flashing different flash images in cxgb4 driver, from Vishal
    Kulkarni.

 4) Add drop frames counter and flow status to tc flower offloading,
    from Po Liu.

 5) Support n-tuple filters in cxgb4, from Vishal Kulkarni.

 6) Various new indirect call avoidance, from Eric Dumazet and Brian
    Vazquez.

 7) Fix BPF verifier failures on 32-bit pointer arithmetic, from
    Yonghong Song.

 8) Support querying and setting hardware address of a port function via
    devlink, use this in mlx5, from Parav Pandit.

 9) Support hw ipsec offload on bonding slaves, from Jarod Wilson.

10) Switch qca8k driver over to phylink, from Jonathan McDowell.

11) In bpftool, show list of processes holding BPF FD references to
    maps, programs, links, and btf objects. From Andrii Nakryiko.

12) Several conversions over to generic power management, from Vaibhav
    Gupta.

13) Add support for SO_KEEPALIVE et al. to bpf_setsockopt(), from Dmitry
    Yakunin.

14) Various https url conversions, from Alexander A. Klimov.

15) Timestamping and PHC support for mscc PHY driver, from Antoine
    Tenart.

16) Support bpf iterating over tcp and udp sockets, from Yonghong Song.

17) Support 5GBASE-T i40e NICs, from Aleksandr Loktionov.

18) Add kTLS RX HW offload support to mlx5e, from Tariq Toukan.

19) Fix the ->ndo_start_xmit() return type to be netdev_tx_t in several
    drivers. From Luc Van Oostenryck.

20) XDP support for xen-netfront, from Denis Kirjanov.

21) Support receive buffer autotuning in MPTCP, from Florian Westphal.

22) Support EF100 chip in sfc driver, from Edward Cree.

23) Add XDP support to mvpp2 driver, from Matteo Croce.

24) Support MPTCP in sock_diag, from Paolo Abeni.

25) Commonize UDP tunnel offloading code by creating udp_tunnel_nic
    infrastructure, from Jakub Kicinski.

26) Several pci_ --> dma_ API conversions, from Christophe JAILLET.

27) Add FLOW_ACTION_POLICE support to mlxsw, from Ido Schimmel.

28) Add SK_LOOKUP bpf program type, from Jakub Sitnicki.

29) Refactor a lot of networking socket option handling code in order to
    avoid set_fs() calls, from Christoph Hellwig.

30) Add rfc4884 support to icmp code, from Willem de Bruijn.

31) Support TBF offload in dpaa2-eth driver, from Ioana Ciornei.

32) Support XDP_REDIRECT in qede driver, from Alexander Lobakin.

33) Support PCI relaxed ordering in mlx5 driver, from Aya Levin.

34) Support TCP syncookies in MPTCP, from Flowian Westphal.

35) Fix several tricky cases of PMTU handling wrt. briding, from Stefano
    Brivio.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2056 commits)
  net: thunderx: initialize VF's mailbox mutex before first usage
  usb: hso: remove bogus check for EINPROGRESS
  usb: hso: no complaint about kmalloc failure
  hso: fix bailout in error case of probe
  ip_tunnel_core: Fix build for archs without _HAVE_ARCH_IPV6_CSUM
  selftests/net: relax cpu affinity requirement in msg_zerocopy test
  mptcp: be careful on subflow creation
  selftests: rtnetlink: make kci_test_encap() return sub-test result
  selftests: rtnetlink: correct the final return value for the test
  net: dsa: sja1105: use detected device id instead of DT one on mismatch
  tipc: set ub->ifindex for local ipv6 address
  ipv6: add ipv6_dev_find()
  net: openvswitch: silence suspicious RCU usage warning
  Revert "vxlan: fix tos value before xmit"
  ptp: only allow phase values lower than 1 period
  farsync: switch from 'pci_' to 'dma_' API
  wan: wanxl: switch from 'pci_' to 'dma_' API
  hv_netvsc: do not use VF device if link is down
  dpaa2-eth: Fix passing zero to 'PTR_ERR' warning
  net: macb: Properly handle phylink on at91sam9x
  ...
2020-08-05 20:13:21 -07:00
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
Kees Cook 3f649ab728 treewide: Remove uninitialized_var() usage
Using uninitialized_var() is dangerous as it papers over real bugs[1]
(or can in the future), and suppresses unrelated compiler warnings
(e.g. "unused variable"). If the compiler thinks it is uninitialized,
either simply initialize the variable or make compiler changes.

In preparation for removing[2] the[3] macro[4], remove all remaining
needless uses with the following script:

git grep '\buninitialized_var\b' | cut -d: -f1 | sort -u | \
	xargs perl -pi -e \
		's/\buninitialized_var\(([^\)]+)\)/\1/g;
		 s:\s*/\* (GCC be quiet|to make compiler happy) \*/$::g;'

drivers/video/fbdev/riva/riva_hw.c was manually tweaked to avoid
pathological white-space.

No outstanding warnings were found building allmodconfig with GCC 9.3.0
for x86_64, i386, arm64, arm, powerpc, powerpc64le, s390x, mips, sparc64,
alpha, and m68k.

[1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/
[2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/
[3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/
[4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/

Reviewed-by: Leon Romanovsky <leonro@mellanox.com> # drivers/infiniband and mlx4/mlx5
Acked-by: Jason Gunthorpe <jgg@mellanox.com> # IB
Acked-by: Kalle Valo <kvalo@codeaurora.org> # wireless drivers
Reviewed-by: Chao Yu <yuchao0@huawei.com> # erofs
Signed-off-by: Kees Cook <keescook@chromium.org>
2020-07-16 12:35:15 -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
Vlad Buslov 4ce70b4aed net: sched: sch_htb: don't call qdisc_put() while holding tree lock
Recent changes that removed rtnl dependency from rules update path of tc
also made tcf_block_put() function sleeping. This function is called from
ops->destroy() of several Qdisc implementations, which in turn is called by
qdisc_put(). Some Qdiscs call qdisc_put() while holding sch tree spinlock,
which results sleeping-while-atomic BUG.

Steps to reproduce for htb:

tc qdisc add dev ens1f0 root handle 1: htb default 12
tc class add dev ens1f0 parent 1: classid 1:1 htb rate 100kbps ceil 100kbps
tc qdisc add dev ens1f0 parent 1:1 handle 40: sfq perturb 10
tc class add dev ens1f0 parent 1:1 classid 1:2 htb rate 100kbps ceil 100kbps

Resulting dmesg:

[ 4791.148551] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:909
[ 4791.151354] in_atomic(): 1, irqs_disabled(): 0, pid: 27273, name: tc
[ 4791.152805] INFO: lockdep is turned off.
[ 4791.153605] CPU: 19 PID: 27273 Comm: tc Tainted: G        W         5.3.0-rc8+ #721
[ 4791.154336] Hardware name: Supermicro SYS-2028TP-DECR/X10DRT-P, BIOS 2.0b 03/30/2017
[ 4791.155075] Call Trace:
[ 4791.155803]  dump_stack+0x85/0xc0
[ 4791.156529]  ___might_sleep.cold+0xac/0xbc
[ 4791.157251]  __mutex_lock+0x5b/0x960
[ 4791.157966]  ? console_unlock+0x363/0x5d0
[ 4791.158676]  ? tcf_chain0_head_change_cb_del.isra.0+0x1b/0xf0
[ 4791.159395]  ? tcf_chain0_head_change_cb_del.isra.0+0x1b/0xf0
[ 4791.160103]  tcf_chain0_head_change_cb_del.isra.0+0x1b/0xf0
[ 4791.160815]  tcf_block_put_ext.part.0+0x21/0x50
[ 4791.161530]  tcf_block_put+0x50/0x70
[ 4791.162233]  sfq_destroy+0x15/0x50 [sch_sfq]
[ 4791.162936]  qdisc_destroy+0x5f/0x160
[ 4791.163642]  htb_change_class.cold+0x5df/0x69d [sch_htb]
[ 4791.164505]  tc_ctl_tclass+0x19d/0x480
[ 4791.165360]  rtnetlink_rcv_msg+0x170/0x4b0
[ 4791.166191]  ? netlink_deliver_tap+0x95/0x400
[ 4791.166907]  ? rtnl_dellink+0x2d0/0x2d0
[ 4791.167625]  netlink_rcv_skb+0x49/0x110
[ 4791.168345]  netlink_unicast+0x171/0x200
[ 4791.169058]  netlink_sendmsg+0x224/0x3f0
[ 4791.169771]  sock_sendmsg+0x5e/0x60
[ 4791.170475]  ___sys_sendmsg+0x2ae/0x330
[ 4791.171183]  ? ___sys_recvmsg+0x159/0x1f0
[ 4791.171894]  ? do_wp_page+0x9c/0x790
[ 4791.172595]  ? __handle_mm_fault+0xcd3/0x19e0
[ 4791.173309]  __sys_sendmsg+0x59/0xa0
[ 4791.174024]  do_syscall_64+0x5c/0xb0
[ 4791.174725]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
[ 4791.175435] RIP: 0033:0x7f0aa41497b8
[ 4791.176129] Code: 89 02 48 c7 c0 ff ff ff ff eb bb 0f 1f 80 00 00 00 00 f3 0f 1e fa 48 8d 05 65 8f 0c 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 48 83 ec 28 89 5
4
[ 4791.177532] RSP: 002b:00007fff4e37d588 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[ 4791.178243] RAX: ffffffffffffffda RBX: 000000005d8132f7 RCX: 00007f0aa41497b8
[ 4791.178947] RDX: 0000000000000000 RSI: 00007fff4e37d5f0 RDI: 0000000000000003
[ 4791.179662] RBP: 0000000000000000 R08: 0000000000000001 R09: 00000000020149a0
[ 4791.180382] R10: 0000000000404eda R11: 0000000000000246 R12: 0000000000000001
[ 4791.181100] R13: 000000000047f640 R14: 0000000000000000 R15: 0000000000000000

In htb_change_class() function save parent->leaf.q to local temporary
variable and put reference to it after sch tree lock is released in order
not to call potentially sleeping cls API in atomic section. This is safe to
do because Qdisc has already been reset by qdisc_purge_queue() inside sch
tree lock critical section.

Fixes: c266f64dbf ("net: sched: protect block state with mutex")
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-27 12:13:55 +02:00
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00
Cong Wang b362487a3b sch_htb: redefine htb qdisc overlimits
In commit 3c75f6ee13 ("net_sched: sch_htb: add per class overlimits counter")
we added an overlimits counter for each HTB class which could
properly reflect how many times we use up all the bandwidth
on each class. However, the overlimits counter in HTB qdisc
does not, it is way bigger than the sum of each HTB class.
In fact, this qdisc overlimits counter increases when we have
no skb to dequeue, which happens more often than we run out of
bandwidth.

It makes more sense to make this qdisc overlimits counter just
be a sum of each HTB class, in case people still get confused.

I have verified this patch with one single HTB class, where HTB
qdisc counters now always match HTB class counters as expected.

Eric suggested we could fold this field into 'direct_pkts' as
we only use its 32bit on 64bit CPU, this saves one cache line.

Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-05 21:55:20 -07:00
Johannes Berg 8cb081746c netlink: make validation more configurable for future strictness
We currently have two levels of strict validation:

 1) liberal (default)
     - undefined (type >= max) & NLA_UNSPEC attributes accepted
     - attribute length >= expected accepted
     - garbage at end of message accepted
 2) strict (opt-in)
     - NLA_UNSPEC attributes accepted
     - attribute length >= expected accepted

Split out parsing strictness into four different options:
 * TRAILING     - check that there's no trailing data after parsing
                  attributes (in message or nested)
 * MAXTYPE      - reject attrs > max known type
 * UNSPEC       - reject attributes with NLA_UNSPEC policy entries
 * STRICT_ATTRS - strictly validate attribute size

The default for future things should be *everything*.
The current *_strict() is a combination of TRAILING and MAXTYPE,
and is renamed to _deprecated_strict().
The current regular parsing has none of this, and is renamed to
*_parse_deprecated().

Additionally it allows us to selectively set one of the new flags
even on old policies. Notably, the UNSPEC flag could be useful in
this case, since it can be arranged (by filling in the policy) to
not be an incompatible userspace ABI change, but would then going
forward prevent forgetting attribute entries. Similar can apply
to the POLICY flag.

We end up with the following renames:
 * nla_parse           -> nla_parse_deprecated
 * nla_parse_strict    -> nla_parse_deprecated_strict
 * nlmsg_parse         -> nlmsg_parse_deprecated
 * nlmsg_parse_strict  -> nlmsg_parse_deprecated_strict
 * nla_parse_nested    -> nla_parse_nested_deprecated
 * nla_validate_nested -> nla_validate_nested_deprecated

Using spatch, of course:
    @@
    expression TB, MAX, HEAD, LEN, POL, EXT;
    @@
    -nla_parse(TB, MAX, HEAD, LEN, POL, EXT)
    +nla_parse_deprecated(TB, MAX, HEAD, LEN, POL, EXT)

    @@
    expression NLH, HDRLEN, TB, MAX, POL, EXT;
    @@
    -nlmsg_parse(NLH, HDRLEN, TB, MAX, POL, EXT)
    +nlmsg_parse_deprecated(NLH, HDRLEN, TB, MAX, POL, EXT)

    @@
    expression NLH, HDRLEN, TB, MAX, POL, EXT;
    @@
    -nlmsg_parse_strict(NLH, HDRLEN, TB, MAX, POL, EXT)
    +nlmsg_parse_deprecated_strict(NLH, HDRLEN, TB, MAX, POL, EXT)

    @@
    expression TB, MAX, NLA, POL, EXT;
    @@
    -nla_parse_nested(TB, MAX, NLA, POL, EXT)
    +nla_parse_nested_deprecated(TB, MAX, NLA, POL, EXT)

    @@
    expression START, MAX, POL, EXT;
    @@
    -nla_validate_nested(START, MAX, POL, EXT)
    +nla_validate_nested_deprecated(START, MAX, POL, EXT)

    @@
    expression NLH, HDRLEN, MAX, POL, EXT;
    @@
    -nlmsg_validate(NLH, HDRLEN, MAX, POL, EXT)
    +nlmsg_validate_deprecated(NLH, HDRLEN, MAX, POL, EXT)

For this patch, don't actually add the strict, non-renamed versions
yet so that it breaks compile if I get it wrong.

Also, while at it, make nla_validate and nla_parse go down to a
common __nla_validate_parse() function to avoid code duplication.

Ultimately, this allows us to have very strict validation for every
new caller of nla_parse()/nlmsg_parse() etc as re-introduced in the
next patch, while existing things will continue to work as is.

In effect then, this adds fully strict validation for any new command.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-27 17:07:21 -04:00
Michal Kubecek ae0be8de9a netlink: make nla_nest_start() add NLA_F_NESTED flag
Even if the NLA_F_NESTED flag was introduced more than 11 years ago, most
netlink based interfaces (including recently added ones) are still not
setting it in kernel generated messages. Without the flag, message parsers
not aware of attribute semantics (e.g. wireshark dissector or libmnl's
mnl_nlmsg_fprintf()) cannot recognize nested attributes and won't display
the structure of their contents.

Unfortunately we cannot just add the flag everywhere as there may be
userspace applications which check nlattr::nla_type directly rather than
through a helper masking out the flags. Therefore the patch renames
nla_nest_start() to nla_nest_start_noflag() and introduces nla_nest_start()
as a wrapper adding NLA_F_NESTED. The calls which add NLA_F_NESTED manually
are rewritten to use nla_nest_start().

Except for changes in include/net/netlink.h, the patch was generated using
this semantic patch:

@@ expression E1, E2; @@
-nla_nest_start(E1, E2)
+nla_nest_start_noflag(E1, E2)

@@ expression E1, E2; @@
-nla_nest_start_noflag(E1, E2 | NLA_F_NESTED)
+nla_nest_start(E1, E2)

Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-27 17:03:44 -04:00
Paolo Abeni e5f0e8f8e4 net: sched: introduce and use qdisc tree flush/purge helpers
The same code to flush qdisc tree and purge the qdisc queue
is duplicated in many places and in most cases it does not
respect NOLOCK qdisc: the global backlog len is used and the
per CPU values are ignored.

This change addresses the above, factoring-out the relevant
code and using the helpers introduced by the previous patch
to fetch the correct backlog len.

Fixes: c5ad119fb6 ("net: sched: pfifo_fast use skb_array")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-01 14:50:13 -07:00
Paolo Abeni 5dd431b6b9 net: sched: introduce and use qstats read helpers
Classful qdiscs can't access directly the child qdiscs backlog
length: if such qdisc is NOLOCK, per CPU values should be
accounted instead.

Most qdiscs no not respect the above. As a result, qstats fetching
for most classful qdisc is currently incorrect: if the child qdisc is
NOLOCK, it always reports 0 len backlog.

This change introduces a pair of helpers to safely fetch
both backlog and qlen and use them in stats class dumping
functions, fixing the above issue and cleaning a bit the code.

DRR needs also to access the child qdisc queue length, so it
needs custom handling.

Fixes: c5ad119fb6 ("net: sched: pfifo_fast use skb_array")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-01 14:50:13 -07:00
Toke Høiland-Jørgensen f6bab19931 sched: Avoid dereferencing skb pointer after child enqueue
Parent qdiscs may dereference the pointer to the enqueued skb after
enqueue. However, both CAKE and TBF call consume_skb() on the original skb
when splitting GSO packets, leading to a potential use-after-free in the
parent. Fix this by avoiding dereferencing the skb pointer after enqueueing
to the child.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-15 20:12:00 -08:00