Commit Graph

57 Commits

Author SHA1 Message Date
Ido Schimmel c2ccf84ecb net/sched: act_api: Add extack to offload_act_setup() callback
The callback is used by various actions to populate the flow action
structure prior to offload. Pass extack to this callback so that the
various actions will be able to report accurate error messages to user
space.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-08 13:45:43 +01:00
Baowen Zheng 8cbfe939ab flow_offload: allow user to offload tc action to net device
Use flow_indr_dev_register/flow_indr_dev_setup_offload to
offload tc action.

We need to call tc_cleanup_flow_action to clean up tc action entry since
in tc_setup_action, some actions may hold dev refcnt, especially the mirror
action.

Signed-off-by: Baowen Zheng <baowen.zheng@corigine.com>
Signed-off-by: Louis Peens <louis.peens@corigine.com>
Signed-off-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-19 14:08:48 +00:00
Baowen Zheng c54e1d920f flow_offload: add ops to tc_action_ops for flow action setup
Add a new ops to tc_action_ops for flow action setup.

Refactor function tc_setup_flow_action to use this new ops.

We make this change to facilitate to add standalone action module.

We will also use this ops to offload action independent of filter
in following patch.

Signed-off-by: Baowen Zheng <baowen.zheng@corigine.com>
Signed-off-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-19 14:08:48 +00:00
Baowen Zheng 40bd094d65 flow_offload: fill flags to action structure
Fill flags to action structure to allow user control if
the action should be offloaded to hardware or not.

Signed-off-by: Baowen Zheng <baowen.zheng@corigine.com>
Signed-off-by: Louis Peens <louis.peens@corigine.com>
Signed-off-by: Simon Horman <simon.horman@corigine.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-19 14:08:47 +00:00
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
Cong Wang 695176bfe5 net_sched: refactor TC action init API
TC action ->init() API has 10 parameters, it becomes harder
to read. Some of them are just boolean and can be replaced
by flags. Similarly for the internal API tcf_action_init()
and tcf_exts_validate().

This patch converts them to flags and fold them into
the upper 16 bits of "flags", whose lower 16 bits are still
reserved for user-space. More specifically, the following
kernel flags are introduced:

TCA_ACT_FLAGS_POLICE replace 'name' in a few contexts, to
distinguish whether it is compatible with policer.

TCA_ACT_FLAGS_BIND replaces 'bind', to indicate whether
this action is bound to a filter.

TCA_ACT_FLAGS_REPLACE  replaces 'ovr' in most contexts,
means we are replacing an existing action.

TCA_ACT_FLAGS_NO_RTNL replaces 'rtnl_held' but has the
opposite meaning, because we still hold RTNL in most
cases.

The only user-space flag TCA_ACT_FLAGS_NO_PERCPU_STATS is
untouched and still stored as before.

I have tested this patch with tdc and I do not see any
failure related to this patch.

Tested-by: Vlad Buslov <vladbu@nvidia.com>
Acked-by: Jamal Hadi Salim<jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-02 10:24:38 +01:00
Ido Schimmel a03e99d39f psample: Encapsulate packet metadata in a struct
Currently, callers of psample_sample_packet() pass three metadata
attributes: Ingress port, egress port and truncated size. Subsequent
patches are going to add more attributes (e.g., egress queue occupancy),
which also need an indication whether they are valid or not.

Encapsulate packet metadata in a struct in order to keep the number of
arguments reasonable.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-14 15:00:43 -07:00
Ido Schimmel 58c04397f7 sched: act_sample: Implement stats_update callback
Implement this callback in order to get the offloaded stats added to the
kernel stats.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-10 12:45:15 -08:00
Cong Wang e49d8c22f1 net_sched: defer tcf_idr_insert() in tcf_action_init_1()
All TC actions call tcf_idr_insert() for new action at the end
of their ->init(), so we can actually move it to a central place
in tcf_action_init_1().

And once the action is inserted into the global IDR, other parallel
process could free it immediately as its refcnt is still 1, so we can
not fail after this, we need to move it after the goto action
validation to avoid handling the failure case after insertion.

This is found during code review, is not directly triggered by syzbot.
And this prepares for the next patch.

Cc: Vlad Buslov <vladbu@mellanox.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-24 19:46:21 -07:00
Vlad Buslov 7a47281439 net: sched: lock action when translating it to flow_action infra
In order to remove dependency on rtnl lock, take action's tcfa_lock when
constructing its representation as flow_action_entry structure.

Refactor tcf_sample_get_group() to assume that caller holds tcf_lock and
don't take it manually. This callback is only called from flow_action infra
representation translator which now calls it with tcf_lock held, so this
refactoring is necessary to prevent deadlock.

Allocate memory with GFP_ATOMIC flag for ip_tunnel_info copy because
tcf_tunnel_info_copy() is only called from flow_action representation infra
code with tcf_lock spinlock taken.

Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-17 14:17:02 -08:00
Linus Torvalds 1ae78780ed Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Dynamic tick (nohz) updates, perhaps most notably changes to force
     the tick on when needed due to lengthy in-kernel execution on CPUs
     on which RCU is waiting.

   - Linux-kernel memory consistency model updates.

   - Replace rcu_swap_protected() with rcu_prepace_pointer().

   - Torture-test updates.

   - Documentation updates.

   - Miscellaneous fixes"

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (51 commits)
  security/safesetid: Replace rcu_swap_protected() with rcu_replace_pointer()
  net/sched: Replace rcu_swap_protected() with rcu_replace_pointer()
  net/netfilter: Replace rcu_swap_protected() with rcu_replace_pointer()
  net/core: Replace rcu_swap_protected() with rcu_replace_pointer()
  bpf/cgroup: Replace rcu_swap_protected() with rcu_replace_pointer()
  fs/afs: Replace rcu_swap_protected() with rcu_replace_pointer()
  drivers/scsi: Replace rcu_swap_protected() with rcu_replace_pointer()
  drm/i915: Replace rcu_swap_protected() with rcu_replace_pointer()
  x86/kvm/pmu: Replace rcu_swap_protected() with rcu_replace_pointer()
  rcu: Upgrade rcu_swap_protected() to rcu_replace_pointer()
  rcu: Suppress levelspread uninitialized messages
  rcu: Fix uninitialized variable in nocb_gp_wait()
  rcu: Update descriptions for rcu_future_grace_period tracepoint
  rcu: Update descriptions for rcu_nocb_wake tracepoint
  rcu: Remove obsolete descriptions for rcu_barrier tracepoint
  rcu: Ensure that ->rcu_urgent_qs is set before resched IPI
  workqueue: Convert for_each_wq to use built-in list check
  rcu: Several rcu_segcblist functions can be static
  rcu: Remove unused function hlist_bl_del_init_rcu()
  Documentation: Rename rcu_node_context_switch() to rcu_note_context_switch()
  ...
2019-11-26 15:42:43 -08:00
Vlad Buslov e382267860 net: sched: update action implementations to support flags
Extend struct tc_action with new "tcfa_flags" field. Set the field in
tcf_idr_create() function and provide new helper
tcf_idr_create_from_flags() that derives 'cpustats' boolean from flags
value. Update individual hardware-offloaded actions init() to pass their
"flags" argument to new helper in order to skip percpu stats allocation
when user requested it through flags.

Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-30 18:07:51 -07:00
Vlad Buslov abbb0d3363 net: sched: extend TCA_ACT space with TCA_ACT_FLAGS
Extend TCA_ACT space with nla_bitfield32 flags. Add
TCA_ACT_FLAGS_NO_PERCPU_STATS as the only allowed flag. Parse the flags in
tcf_action_init_1() and pass resulting value as additional argument to
a_o->init().

Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-30 18:07:50 -07:00
Paul E. McKenney 445d374931 net/sched: Replace rcu_swap_protected() with rcu_replace_pointer()
This commit replaces the use of rcu_swap_protected() with the more
intuitively appealing rcu_replace_pointer() as a step towards removing
rcu_swap_protected().

Link: https://lore.kernel.org/lkml/CAHk-=wiAsJLw1egFEE=Z7-GGtM6wcvtyytXZA1+BHqta4gg6Hw@mail.gmail.com/
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
[ paulmck: From rcu_replace() to rcu_replace_pointer() per Ingo Molnar. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.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: <netdev@vger.kernel.org>
Cc: <linux-kernel@vger.kernel.org>
2019-10-30 08:45:48 -07:00
Davide Caratti 92974a1d00 net/sched: act_sample: don't push mac header on ip6gre ingress
current 'sample' action doesn't push the mac header of ingress packets if
they are received by a layer 3 tunnel (like gre or sit); but it forgot to
check for gre over ipv6, so the following script:

 # tc q a dev $d clsact
 # tc f a dev $d ingress protocol ip flower ip_proto icmp action sample \
 > group 100 rate 1
 # psample -v -g 100

dumps everything, including outer header and mac, when $d is a gre tunnel
over ipv6. Fix this adding a missing label for ARPHRD_IP6GRE devices.

Fixes: 5c5670fae4 ("net/sched: Introduce sample tc action")
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Reviewed-by: Yotam Gigi <yotam.gi@gmail.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-09-20 17:01:59 -07:00
Vlad Buslov 4a5da47d5c net: sched: take reference to psample group in flow_action infra
With recent patch set that removed rtnl lock dependency from cls hardware
offload API rtnl lock is only taken when reading action data and can be
released after action-specific data is parsed into intermediate
representation. However, sample action psample group is passed by pointer
without obtaining reference to it first, which makes it possible to
concurrently overwrite the action and deallocate object pointed by
psample_group pointer after rtnl lock is released but before driver
finished using the pointer.

To prevent such race condition, obtain reference to psample group while it
is used by flow_action infra. Extend psample API with function
psample_group_take() that increments psample group reference counter.
Extend struct tc_action_ops with new get_psample_group() API. Implement the
API for action sample using psample_group_take() and already existing
psample_group_put() as a destructor. Use it in tc_setup_flow_action() to
take reference to psample group pointed to by entry->sample.psample_group
and release it in tc_cleanup_flow_action().

Disable bh when taking psample_groups_lock. The lock is now taken while
holding action tcf_lock that is used by data path and requires bh to be
disabled, so doing the same for psample_groups_lock is necessary to
preserve SOFTIRQ-irq-safety.

Fixes: 918190f50e ("net: sched: flower: don't take rtnl lock for cls hw offloads API")
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-16 09:18:03 +02:00
Vlad Buslov dbf47a2a09 net: sched: act_sample: fix psample group handling on overwrite
Action sample doesn't properly handle psample_group pointer in overwrite
case. Following issues need to be fixed:

- In tcf_sample_init() function RCU_INIT_POINTER() is used to set
  s->psample_group, even though we neither setting the pointer to NULL, nor
  preventing concurrent readers from accessing the pointer in some way.
  Use rcu_swap_protected() instead to safely reset the pointer.

- Old value of s->psample_group is not released or deallocated in any way,
  which results resource leak. Use psample_group_put() on non-NULL value
  obtained with rcu_swap_protected().

- The function psample_group_put() that released reference to struct
  psample_group pointed by rcu-pointer s->psample_group doesn't respect rcu
  grace period when deallocating it. Extend struct psample_group with rcu
  head and use kfree_rcu when freeing it.

Fixes: 5c5670fae4 ("net/sched: Introduce sample tc action")
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-28 15:53:51 -07:00
Cong Wang 981471bd3a net_sched: fix a NULL pointer deref in ipt action
The net pointer in struct xt_tgdtor_param is not explicitly
initialized therefore is still NULL when dereferencing it.
So we have to find a way to pass the correct net pointer to
ipt_destroy_target().

The best way I find is just saving the net pointer inside the per
netns struct tcf_idrinfo, which could make this patch smaller.

Fixes: 0c66dc1ea3 ("netfilter: conntrack: register hooks in netns when needed by ruleset")
Reported-and-tested-by: itugrok@yahoo.com
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-27 15:05:58 -07:00
Dmytro Linkin 7be8ef2cdb net: sched: use temporary variable for actions indexes
Currently init call of all actions (except ipt) init their 'parm'
structure as a direct pointer to nla data in skb. This leads to race
condition when some of the filter actions were initialized successfully
(and were assigned with idr action index that was written directly
into nla data), but then were deleted and retried (due to following
action module missing or classifier-initiated retry), in which case
action init code tries to insert action to idr with index that was
assigned on previous iteration. During retry the index can be reused
by another action that was inserted concurrently, which causes
unintended action sharing between filters.
To fix described race condition, save action idr index to temporary
stack-allocated variable instead on nla data.

Fixes: 0190c1d452 ("net: sched: atomically check-allocate action")
Signed-off-by: Dmytro Linkin <dmitrolin@mellanox.com>
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-05 10:59:14 -07:00
Thomas Gleixner d2912cb15b treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500
Based on 2 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 version 2 as
  published by the free software foundation

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:55 +02:00
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
Davide Caratti fae2708174 net/sched: act_sample: fix divide by zero in the traffic path
the control path of 'sample' action does not validate the value of 'rate'
provided by the user, but then it uses it as divisor in the traffic path.
Validate it in tcf_sample_init(), and return -EINVAL with a proper extack
message in case that value is zero, to fix a splat with the script below:

 # tc f a dev test0 egress matchall action sample rate 0 group 1 index 2
 # tc -s a s action sample
 total acts 1

         action order 0: sample rate 1/0 group 1 pipe
          index 2 ref 1 bind 1 installed 19 sec used 19 sec
         Action statistics:
         Sent 0 bytes 0 pkt (dropped 0, overlimits 0 requeues 0)
         backlog 0b 0p requeues 0
 # ping 192.0.2.1 -I test0 -c1 -q

 divide error: 0000 [#1] SMP PTI
 CPU: 1 PID: 6192 Comm: ping Not tainted 5.1.0-rc2.diag2+ #591
 Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
 RIP: 0010:tcf_sample_act+0x9e/0x1e0 [act_sample]
 Code: 6a f1 85 c0 74 0d 80 3d 83 1a 00 00 00 0f 84 9c 00 00 00 4d 85 e4 0f 84 85 00 00 00 e8 9b d7 9c f1 44 8b 8b e0 00 00 00 31 d2 <41> f7 f1 85 d2 75 70 f6 85 83 00 00 00 10 48 8b 45 10 8b 88 08 01
 RSP: 0018:ffffae320190ba30 EFLAGS: 00010246
 RAX: 00000000b0677d21 RBX: ffff8af1ed9ec000 RCX: 0000000059a9fe49
 RDX: 0000000000000000 RSI: 000000000c7e33b7 RDI: ffff8af23daa0af0
 RBP: ffff8af1ee11b200 R08: 0000000074fcaf7e R09: 0000000000000000
 R10: 0000000000000050 R11: ffffffffb3088680 R12: ffff8af232307f80
 R13: 0000000000000003 R14: ffff8af1ed9ec000 R15: 0000000000000000
 FS:  00007fe9c6d2f740(0000) GS:ffff8af23da80000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007fff6772f000 CR3: 00000000746a2004 CR4: 00000000001606e0
 Call Trace:
  tcf_action_exec+0x7c/0x1c0
  tcf_classify+0x57/0x160
  __dev_queue_xmit+0x3dc/0xd10
  ip_finish_output2+0x257/0x6d0
  ip_output+0x75/0x280
  ip_send_skb+0x15/0x40
  raw_sendmsg+0xae3/0x1410
  sock_sendmsg+0x36/0x40
  __sys_sendto+0x10e/0x140
  __x64_sys_sendto+0x24/0x30
  do_syscall_64+0x60/0x210
  entry_SYSCALL_64_after_hwframe+0x49/0xbe
  [...]
  Kernel panic - not syncing: Fatal exception in interrupt

Add a TDC selftest to document that 'rate' is now being validated.

Reported-by: Matteo Croce <mcroce@redhat.com>
Fixes: 5c5670fae4 ("net/sched: Introduce sample tc action")
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Acked-by: Yotam Gigi <yotam.gi@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-04 10:46:33 -07:00
Davide Caratti e8c87c643e net/sched: act_sample: validate the control action inside init()
the following script:

 # tc qdisc add dev crash0 clsact
 # tc filter add dev crash0 egress matchall \
 > action sample rate 1024 group 4 pass index 90
 # tc actions replace action sample \
 > rate 1024 group 4 goto chain 42 index 90 cookie c1a0c1a0
 # tc actions show action sample

had the following output:

 Error: Failed to init TC action chain.
 We have an error talking to the kernel
 total acts 1

         action order 0: sample rate 1/1024 group 4 goto chain 42
          index 90 ref 2 bind 1
         cookie c1a0c1a0

Then, the first packet transmitted by crash0 made the kernel crash:

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
 #PF error: [normal kernel read fault]
 PGD 8000000079966067 P4D 8000000079966067 PUD 7987b067 PMD 0
 Oops: 0000 [#1] SMP PTI
 CPU: 0 PID: 5 Comm: kworker/0:0 Not tainted 5.0.0-rc4.gotochain_crash+ #536
 Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
 Workqueue: ipv6_addrconf addrconf_dad_work
 RIP: 0010:tcf_action_exec+0xb8/0x100
 Code: 00 00 00 20 74 1d 83 f8 03 75 09 49 83 c4 08 4d 39 ec 75 bc 48 83 c4 10 5b 5d 41 5c 41 5d 41 5e 41 5f c3 49 8b 97 a8 00 00 00 <48> 8b 12 48 89 55 00 48 83 c4 10 5b 5d 41 5c 41 5d 41 5e 41 5f c3
 RSP: 0018:ffffbee60033fad0 EFLAGS: 00010246
 RAX: 000000002000002a RBX: ffff99d7ae6e3b00 RCX: 00000000e555df9b
 RDX: 0000000000000000 RSI: 00000000b0352718 RDI: ffff99d7fda1fcf0
 RBP: ffffbee60033fb70 R08: 0000000070731ab1 R09: 0000000000000400
 R10: 0000000000000000 R11: ffff99d7ac733838 R12: ffff99d7f3c2be00
 R13: ffff99d7f3c2be08 R14: 0000000000000001 R15: ffff99d7f3c2b600
 FS:  0000000000000000(0000) GS:ffff99d7fda00000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000000000 CR3: 00000000797de006 CR4: 00000000001606f0
 Call Trace:
  tcf_classify+0x58/0x120
  __dev_queue_xmit+0x40a/0x890
  ? ndisc_next_option+0x50/0x50
  ? ___neigh_create+0x4d5/0x680
  ? ip6_finish_output2+0x1b5/0x590
  ip6_finish_output2+0x1b5/0x590
  ? ip6_output+0x68/0x110
  ip6_output+0x68/0x110
  ? nf_hook.constprop.28+0x79/0xc0
  ndisc_send_skb+0x248/0x2e0
  ndisc_send_ns+0xf8/0x200
  ? addrconf_dad_work+0x389/0x4b0
  addrconf_dad_work+0x389/0x4b0
  ? __switch_to_asm+0x34/0x70
  ? process_one_work+0x195/0x380
  ? addrconf_dad_completed+0x370/0x370
  process_one_work+0x195/0x380
  worker_thread+0x30/0x390
  ? process_one_work+0x380/0x380
  kthread+0x113/0x130
  ? kthread_park+0x90/0x90
  ret_from_fork+0x35/0x40
 Modules linked in: act_sample psample veth ip6table_filter ip6_tables iptable_filter binfmt_misc ext4 crct10dif_pclmul crc32_pclmul ghash_clmulni_intel mbcache jbd2 snd_hda_codec_generic snd_hda_intel snd_hda_codec snd_hwdep snd_hda_core snd_seq snd_seq_device aesni_intel crypto_simd snd_pcm cryptd glue_helper snd_timer joydev snd pcspkr virtio_balloon i2c_piix4 soundcore nfsd auth_rpcgss nfs_acl lockd grace sunrpc ip_tables xfs ata_generic pata_acpi qxl drm_kms_helper syscopyarea sysfillrect virtio_net sysimgblt fb_sys_fops net_failover ttm failover virtio_blk virtio_console drm ata_piix serio_raw crc32c_intel libata virtio_pci virtio_ring virtio floppy dm_mirror dm_region_hash dm_log dm_mod
 CR2: 0000000000000000

Validating the control action within tcf_sample_init() proved to fix the
above issue. A TDC selftest is added to verify the correct behavior.

Fixes: db50514f9a ("net: sched: add termination action to allow goto chain")
Fixes: 97763dc0f4 ("net_sched: reject unknown tcfa_action values")
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-21 13:26:41 -07:00
Davide Caratti 85d0966fa5 net/sched: prepare TC actions to properly validate the control action
- pass a pointer to struct tcf_proto in each actions's init() handler,
  to allow validating the control action, checking whether the chain
  exists and (eventually) refcounting it.
- remove code that validates the control action after a successful call
  to the action's init() handler, and replace it with a test that forbids
  addition of actions having 'goto_chain' and NULL goto_chain pointer at
  the same time.
- add tcf_action_check_ctrlact(), that will validate the control action
  and eventually allocate the action 'goto_chain' within the init()
  handler.
- add tcf_action_set_ctrlact(), that will assign the control action and
  swap the current 'goto_chain' pointer with the new given one.

This disallows 'goto_chain' on actions that don't initialize it properly
in their init() handler, i.e. calling tcf_action_check_ctrlact() after
successful IDR reservation and then calling tcf_action_set_ctrlact()
to assign 'goto_chain' and 'tcf_action' consistently.

By doing this, the kernel does not leak anymore refcounts when a valid
'goto chain' handle is replaced in TC actions, causing kmemleak splats
like the following one:

 # tc chain add dev dd0 chain 42 ingress protocol ip flower \
 > ip_proto tcp action drop
 # tc chain add dev dd0 chain 43 ingress protocol ip flower \
 > ip_proto udp action drop
 # tc filter add dev dd0 ingress matchall \
 > action gact goto chain 42 index 66
 # tc filter replace dev dd0 ingress matchall \
 > action gact goto chain 43 index 66
 # echo scan >/sys/kernel/debug/kmemleak
 <...>
 unreferenced object 0xffff93c0ee09f000 (size 1024):
 comm "tc", pid 2565, jiffies 4295339808 (age 65.426s)
 hex dump (first 32 bytes):
   00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
   00 00 00 00 08 00 06 00 00 00 00 00 00 00 00 00  ................
 backtrace:
   [<000000009b63f92d>] tc_ctl_chain+0x3d2/0x4c0
   [<00000000683a8d72>] rtnetlink_rcv_msg+0x263/0x2d0
   [<00000000ddd88f8e>] netlink_rcv_skb+0x4a/0x110
   [<000000006126a348>] netlink_unicast+0x1a0/0x250
   [<00000000b3340877>] netlink_sendmsg+0x2c1/0x3c0
   [<00000000a25a2171>] sock_sendmsg+0x36/0x40
   [<00000000f19ee1ec>] ___sys_sendmsg+0x280/0x2f0
   [<00000000d0422042>] __sys_sendmsg+0x5e/0xa0
   [<000000007a6c61f9>] do_syscall_64+0x5b/0x180
   [<00000000ccd07542>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
   [<0000000013eaa334>] 0xffffffffffffffff

Fixes: db50514f9a ("net: sched: add termination action to allow goto chain")
Fixes: 97763dc0f4 ("net_sched: reject unknown tcfa_action values")
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-21 13:26:41 -07:00
Eli Cohen eddd2cf195 net: Change TCA_ACT_* to TCA_ID_* to match that of TCA_ID_POLICE
Modify the kernel users of the TCA_ACT_* macros to use TCA_ID_*. For
example, use TCA_ID_GACT instead of TCA_ACT_GACT. This will align with
TCA_ID_POLICE and also differentiates these identifier, used in struct
tc_action_ops type field, from other macros starting with TCA_ACT_.

To make things clearer, we name the enum defining the TCA_ID_*
identifiers and also change the "type" field of struct tc_action to
id.

Signed-off-by: Eli Cohen <eli@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-10 09:28:43 -08:00
David S. Miller e366fa4350 Merge ra.kernel.org:/pub/scm/linux/kernel/git/davem/net
Two new tls tests added in parallel in both net and net-next.

Used Stephen Rothwell's linux-next resolution.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-18 09:33:27 -07:00
Davide Caratti 34043d250f net/sched: act_sample: fix NULL dereference in the data path
Matteo reported the following splat, testing the datapath of TC 'sample':

 BUG: KASAN: null-ptr-deref in tcf_sample_act+0xc4/0x310
 Read of size 8 at addr 0000000000000000 by task nc/433

 CPU: 0 PID: 433 Comm: nc Not tainted 4.19.0-rc3-kvm #17
 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS ?-20180531_142017-buildhw-08.phx2.fedoraproject.org-1.fc28 04/01/2014
 Call Trace:
  kasan_report.cold.6+0x6c/0x2fa
  tcf_sample_act+0xc4/0x310
  ? dev_hard_start_xmit+0x117/0x180
  tcf_action_exec+0xa3/0x160
  tcf_classify+0xdd/0x1d0
  htb_enqueue+0x18e/0x6b0
  ? deref_stack_reg+0x7a/0xb0
  ? htb_delete+0x4b0/0x4b0
  ? unwind_next_frame+0x819/0x8f0
  ? entry_SYSCALL_64_after_hwframe+0x44/0xa9
  __dev_queue_xmit+0x722/0xca0
  ? unwind_get_return_address_ptr+0x50/0x50
  ? netdev_pick_tx+0xe0/0xe0
  ? save_stack+0x8c/0xb0
  ? kasan_kmalloc+0xbe/0xd0
  ? __kmalloc_track_caller+0xe4/0x1c0
  ? __kmalloc_reserve.isra.45+0x24/0x70
  ? __alloc_skb+0xdd/0x2e0
  ? sk_stream_alloc_skb+0x91/0x3b0
  ? tcp_sendmsg_locked+0x71b/0x15a0
  ? tcp_sendmsg+0x22/0x40
  ? __sys_sendto+0x1b0/0x250
  ? __x64_sys_sendto+0x6f/0x80
  ? do_syscall_64+0x5d/0x150
  ? entry_SYSCALL_64_after_hwframe+0x44/0xa9
  ? __sys_sendto+0x1b0/0x250
  ? __x64_sys_sendto+0x6f/0x80
  ? do_syscall_64+0x5d/0x150
  ? entry_SYSCALL_64_after_hwframe+0x44/0xa9
  ip_finish_output2+0x495/0x590
  ? ip_copy_metadata+0x2e0/0x2e0
  ? skb_gso_validate_network_len+0x6f/0x110
  ? ip_finish_output+0x174/0x280
  __tcp_transmit_skb+0xb17/0x12b0
  ? __tcp_select_window+0x380/0x380
  tcp_write_xmit+0x913/0x1de0
  ? __sk_mem_schedule+0x50/0x80
  tcp_sendmsg_locked+0x49d/0x15a0
  ? tcp_rcv_established+0x8da/0xa30
  ? tcp_set_state+0x220/0x220
  ? clear_user+0x1f/0x50
  ? iov_iter_zero+0x1ae/0x590
  ? __fget_light+0xa0/0xe0
  tcp_sendmsg+0x22/0x40
  __sys_sendto+0x1b0/0x250
  ? __ia32_sys_getpeername+0x40/0x40
  ? _copy_to_user+0x58/0x70
  ? poll_select_copy_remaining+0x176/0x200
  ? __pollwait+0x1c0/0x1c0
  ? ktime_get_ts64+0x11f/0x140
  ? kern_select+0x108/0x150
  ? core_sys_select+0x360/0x360
  ? vfs_read+0x127/0x150
  ? kernel_write+0x90/0x90
  __x64_sys_sendto+0x6f/0x80
  do_syscall_64+0x5d/0x150
  entry_SYSCALL_64_after_hwframe+0x44/0xa9
 RIP: 0033:0x7fefef2b129d
 Code: ff ff ff ff eb b6 0f 1f 80 00 00 00 00 48 8d 05 51 37 0c 00 41 89 ca 8b 00 85 c0 75 20 45 31 c9 45 31 c0 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 6b f3 c3 66 0f 1f 84 00 00 00 00 00 41 56 41
 RSP: 002b:00007fff2f5350c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
 RAX: ffffffffffffffda RBX: 000056118d60c120 RCX: 00007fefef2b129d
 RDX: 0000000000002000 RSI: 000056118d629320 RDI: 0000000000000003
 RBP: 000056118d530370 R08: 0000000000000000 R09: 0000000000000000
 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000002000
 R13: 000056118d5c2a10 R14: 000056118d5c2a10 R15: 000056118d5303b8

tcf_sample_act() tried to update its per-cpu stats, but tcf_sample_init()
forgot to allocate them, because tcf_idr_create() was called with a wrong
value of 'cpustats'. Setting it to true proved to fix the reported crash.

Reported-by: Matteo Croce <mcroce@redhat.com>
Fixes: 65a206c01e ("net/sched: Change act_api and act_xxx modules to use IDR")
Fixes: 5c5670fae4 ("net/sched: Introduce sample tc action")
Tested-by: Matteo Croce <mcroce@redhat.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-14 08:46:28 -07:00
Cong Wang f061b48c17 Revert "net: sched: act: add extack for lookup callback"
This reverts commit 331a9295de ("net: sched: act: add extack for lookup callback").

This extack is never used after 6 months... In fact, it can be just
set in the caller, right after ->lookup().

Cc: Alexander Aring <aring@mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-31 22:50:15 -07:00
Cong Wang 97a3f84f2c net_sched: remove unnecessary ops->delete()
All ops->delete() wants is getting the tn->idrinfo, but we already
have tc_action before calling ops->delete(), and tc_action has
a pointer ->idrinfo.

More importantly, each type of action does the same thing, that is,
just calling tcf_idr_delete_index().

So it can be just removed.

Fixes: b409074e66 ("net: sched: add 'delete' function to action ops")
Cc: Jiri Pirko <jiri@mellanox.com>
Cc: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-21 12:45:44 -07:00
Vlad Buslov 653cd284a8 net: sched: always disable bh when taking tcf_lock
Recently, ops->init() and ops->dump() of all actions were modified to
always obtain tcf_lock when accessing private action state. Actions that
don't depend on tcf_lock for synchronization with their data path use
non-bh locking API. However, tcf_lock is also used to protect rate
estimator stats in softirq context by timer callback.

Change ops->init() and ops->dump() of all actions to disable bh when using
tcf_lock to prevent deadlock reported by following lockdep warning:

[  105.470398] ================================
[  105.475014] WARNING: inconsistent lock state
[  105.479628] 4.18.0-rc8+ #664 Not tainted
[  105.483897] --------------------------------
[  105.488511] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
[  105.494871] swapper/16/0 [HC0[0]:SC1[1]:HE1:SE0] takes:
[  105.500449] 00000000f86c012e (&(&p->tcfa_lock)->rlock){+.?.}, at: est_fetch_counters+0x3c/0xa0
[  105.509696] {SOFTIRQ-ON-W} state was registered at:
[  105.514925]   _raw_spin_lock+0x2c/0x40
[  105.519022]   tcf_bpf_init+0x579/0x820 [act_bpf]
[  105.523990]   tcf_action_init_1+0x4e4/0x660
[  105.528518]   tcf_action_init+0x1ce/0x2d0
[  105.532880]   tcf_exts_validate+0x1d8/0x200
[  105.537416]   fl_change+0x55a/0x268b [cls_flower]
[  105.542469]   tc_new_tfilter+0x748/0xa20
[  105.546738]   rtnetlink_rcv_msg+0x56a/0x6d0
[  105.551268]   netlink_rcv_skb+0x18d/0x200
[  105.555628]   netlink_unicast+0x2d0/0x370
[  105.559990]   netlink_sendmsg+0x3b9/0x6a0
[  105.564349]   sock_sendmsg+0x6b/0x80
[  105.568271]   ___sys_sendmsg+0x4a1/0x520
[  105.572547]   __sys_sendmsg+0xd7/0x150
[  105.576655]   do_syscall_64+0x72/0x2c0
[  105.580757]   entry_SYSCALL_64_after_hwframe+0x49/0xbe
[  105.586243] irq event stamp: 489296
[  105.590084] hardirqs last  enabled at (489296): [<ffffffffb507e639>] _raw_spin_unlock_irq+0x29/0x40
[  105.599765] hardirqs last disabled at (489295): [<ffffffffb507e745>] _raw_spin_lock_irq+0x15/0x50
[  105.609277] softirqs last  enabled at (489292): [<ffffffffb413a6a3>] irq_enter+0x83/0xa0
[  105.618001] softirqs last disabled at (489293): [<ffffffffb413a800>] irq_exit+0x140/0x190
[  105.626813]
               other info that might help us debug this:
[  105.633976]  Possible unsafe locking scenario:

[  105.640526]        CPU0
[  105.643325]        ----
[  105.646125]   lock(&(&p->tcfa_lock)->rlock);
[  105.650747]   <Interrupt>
[  105.653717]     lock(&(&p->tcfa_lock)->rlock);
[  105.658514]
                *** DEADLOCK ***

[  105.665349] 1 lock held by swapper/16/0:
[  105.669629]  #0: 00000000a640ad99 ((&est->timer)){+.-.}, at: call_timer_fn+0x10b/0x550
[  105.678200]
               stack backtrace:
[  105.683194] CPU: 16 PID: 0 Comm: swapper/16 Not tainted 4.18.0-rc8+ #664
[  105.690249] Hardware name: Supermicro SYS-2028TP-DECR/X10DRT-P, BIOS 2.0b 03/30/2017
[  105.698626] Call Trace:
[  105.701421]  <IRQ>
[  105.703791]  dump_stack+0x92/0xeb
[  105.707461]  print_usage_bug+0x336/0x34c
[  105.711744]  mark_lock+0x7c9/0x980
[  105.715500]  ? print_shortest_lock_dependencies+0x2e0/0x2e0
[  105.721424]  ? check_usage_forwards+0x230/0x230
[  105.726315]  __lock_acquire+0x923/0x26f0
[  105.730597]  ? debug_show_all_locks+0x240/0x240
[  105.735478]  ? mark_lock+0x493/0x980
[  105.739412]  ? check_chain_key+0x140/0x1f0
[  105.743861]  ? __lock_acquire+0x836/0x26f0
[  105.748323]  ? lock_acquire+0x12e/0x290
[  105.752516]  lock_acquire+0x12e/0x290
[  105.756539]  ? est_fetch_counters+0x3c/0xa0
[  105.761084]  _raw_spin_lock+0x2c/0x40
[  105.765099]  ? est_fetch_counters+0x3c/0xa0
[  105.769633]  est_fetch_counters+0x3c/0xa0
[  105.773995]  est_timer+0x87/0x390
[  105.777670]  ? est_fetch_counters+0xa0/0xa0
[  105.782210]  ? lock_acquire+0x12e/0x290
[  105.786410]  call_timer_fn+0x161/0x550
[  105.790512]  ? est_fetch_counters+0xa0/0xa0
[  105.795055]  ? del_timer_sync+0xd0/0xd0
[  105.799249]  ? __lock_is_held+0x93/0x110
[  105.803531]  ? mark_held_locks+0x20/0xe0
[  105.807813]  ? _raw_spin_unlock_irq+0x29/0x40
[  105.812525]  ? est_fetch_counters+0xa0/0xa0
[  105.817069]  ? est_fetch_counters+0xa0/0xa0
[  105.821610]  run_timer_softirq+0x3c4/0x9f0
[  105.826064]  ? lock_acquire+0x12e/0x290
[  105.830257]  ? __bpf_trace_timer_class+0x10/0x10
[  105.835237]  ? __lock_is_held+0x25/0x110
[  105.839517]  __do_softirq+0x11d/0x7bf
[  105.843542]  irq_exit+0x140/0x190
[  105.847208]  smp_apic_timer_interrupt+0xac/0x3b0
[  105.852182]  apic_timer_interrupt+0xf/0x20
[  105.856628]  </IRQ>
[  105.859081] RIP: 0010:cpuidle_enter_state+0xd8/0x4d0
[  105.864395] Code: 46 ff 48 89 44 24 08 0f 1f 44 00 00 31 ff e8 cf ec 46 ff 80 7c 24 07 00 0f 85 1d 02 00 00 e8 9f 90 4b ff fb 66 0f 1f 44 00 00 <4c> 8b 6c 24 08 4d 29 fd 0f 80 36 03 00 00 4c 89 e8 48 ba cf f7 53
[  105.884288] RSP: 0018:ffff8803ad94fd20 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
[  105.892494] RAX: 0000000000000000 RBX: ffffe8fb300829c0 RCX: ffffffffb41e19e1
[  105.899988] RDX: 0000000000000007 RSI: dffffc0000000000 RDI: ffff8803ad9358ac
[  105.907503] RBP: ffffffffb6636300 R08: 0000000000000004 R09: 0000000000000000
[  105.914997] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000004
[  105.922487] R13: ffffffffb6636140 R14: ffffffffb66362d8 R15: 000000188d36091b
[  105.929988]  ? trace_hardirqs_on_caller+0x141/0x2d0
[  105.935232]  do_idle+0x28e/0x320
[  105.938817]  ? arch_cpu_idle_exit+0x40/0x40
[  105.943361]  ? mark_lock+0x8c1/0x980
[  105.947295]  ? _raw_spin_unlock_irqrestore+0x32/0x60
[  105.952619]  cpu_startup_entry+0xc2/0xd0
[  105.956900]  ? cpu_in_idle+0x20/0x20
[  105.960830]  ? _raw_spin_unlock_irqrestore+0x32/0x60
[  105.966146]  ? trace_hardirqs_on_caller+0x141/0x2d0
[  105.971391]  start_secondary+0x2b5/0x360
[  105.975669]  ? set_cpu_sibling_map+0x1330/0x1330
[  105.980654]  secondary_startup_64+0xa5/0xb0

Taking tcf_lock in sample action with bh disabled causes lockdep to issue a
warning regarding possible irq lock inversion dependency between tcf_lock,
and psample_groups_lock that is taken when holding tcf_lock in sample init:

[  162.108959]  Possible interrupt unsafe locking scenario:

[  162.116386]        CPU0                    CPU1
[  162.121277]        ----                    ----
[  162.126162]   lock(psample_groups_lock);
[  162.130447]                                local_irq_disable();
[  162.136772]                                lock(&(&p->tcfa_lock)->rlock);
[  162.143957]                                lock(psample_groups_lock);
[  162.150813]   <Interrupt>
[  162.153808]     lock(&(&p->tcfa_lock)->rlock);
[  162.158608]
                *** DEADLOCK ***

In order to prevent potential lock inversion dependency between tcf_lock
and psample_groups_lock, extract call to psample_group_get() from tcf_lock
protected section in sample action init function.

Fixes: 4e232818bd ("net: sched: act_mirred: remove dependency on rtnl lock")
Fixes: 764e9a2448 ("net: sched: act_vlan: remove dependency on rtnl lock")
Fixes: 729e012609 ("net: sched: act_tunnel_key: remove dependency on rtnl lock")
Fixes: d772849566 ("net: sched: act_sample: remove dependency on rtnl lock")
Fixes: e8917f4370 ("net: sched: act_gact: remove dependency on rtnl lock")
Fixes: b6a2b971c0 ("net: sched: act_csum: remove dependency on rtnl lock")
Fixes: 2142236b45 ("net: sched: act_bpf: remove dependency on rtnl lock")
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-19 10:46:21 -07:00
Vlad Buslov d772849566 net: sched: act_sample: remove dependency on rtnl lock
Use tcf spinlock to protect private sample action data from concurrent
modification during dump and init.

Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-11 12:37:09 -07:00
Paolo Abeni 7fd4b288ea tc/act: remove unneeded RCU lock in action callback
Each lockless action currently does its own RCU locking in ->act().
This allows using plain RCU accessor, even if the context
is really RCU BH.

This change drops the per action RCU lock, replace the accessors
with the _bh variant, cleans up a bit the surrounding code and
documents the RCU status in the relevant header.
No functional nor performance change is intended.

The goal of this patch is clarifying that the RCU critical section
used by the tc actions extends up to the classifier's caller.

v1 -> v2:
 - preserve rcu lock in act_bpf: it's needed by eBPF helpers,
   as pointed out by Daniel

v3 -> v4:
 - fixed some typos in the commit message (JiriP)

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-30 09:31:13 -07:00
Vlad Buslov 0190c1d452 net: sched: atomically check-allocate action
Implement function that atomically checks if action exists and either takes
reference to it, or allocates idr slot for action index to prevent
concurrent allocations of actions with same index. Use EBUSY error pointer
to indicate that idr slot is reserved.

Implement cleanup helper function that removes temporary error pointer from
idr. (in case of error between idr allocation and insertion of newly
created action to specified index)

Refactor all action init functions to insert new action to idr using this
API.

Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-08 12:42:29 +09:00
Vlad Buslov 4e8ddd7f17 net: sched: don't release reference on action overwrite
Return from action init function with reference to action taken,
even when overwriting existing action.

Action init API initializes its fourth argument (pointer to pointer to tc
action) to either existing action with same index or newly created action.
In case of existing index(and bind argument is zero), init function returns
without incrementing action reference counter. Caller of action init then
proceeds working with action, without actually holding reference to it.
This means that action could be deleted concurrently.

Change action init behavior to always take reference to action before
returning successfully, in order to protect from concurrent deletion.

Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-08 12:42:29 +09:00
Vlad Buslov b409074e66 net: sched: add 'delete' function to action ops
Extend action ops with 'delete' function. Each action type to implements
its own delete function that doesn't depend on rtnl lock.

Implement delete function that is required to delete actions without
holding rtnl lock. Use action API function that atomically deletes action
only if it is still in action idr. This implementation prevents concurrent
threads from deleting same action twice.

Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-08 12:42:29 +09:00
Vlad Buslov 789871bb2a net: sched: implement unlocked action init API
Add additional 'rtnl_held' argument to act API init functions. It is
required to implement actions that need to release rtnl lock before loading
kernel module and reacquire if afterwards.

Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-08 12:42:28 +09:00
Vlad Buslov 036bb44327 net: sched: change type of reference and bind counters
Change type of action reference counter to refcount_t.

Change type of action bind counter to atomic_t.
This type is used to allow decrementing bind counter without testing
for 0 result.

Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-08 12:42:28 +09:00
Kirill Tkhai 2f635ceeb2 net: Drop pernet_operations::async
Synchronous pernet_operations are not allowed anymore.
All are asynchronous. So, drop the structure member.

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-27 13:18:09 -04:00
David S. Miller 03fe2debbb Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Fun set of conflict resolutions here...

For the mac80211 stuff, these were fortunately just parallel
adds.  Trivially resolved.

In drivers/net/phy/phy.c we had a bug fix in 'net' that moved the
function phy_disable_interrupts() earlier in the file, whilst in
'net-next' the phy_error() call from this function was removed.

In net/ipv4/xfrm4_policy.c, David Ahern's changes to remove the
'rt_table_id' member of rtable collided with a bug fix in 'net' that
added a new struct member "rt_mtu_locked" which needs to be copied
over here.

The mlxsw driver conflict consisted of net-next separating
the span code and definitions into separate files, whilst
a 'net' bug fix made some changes to that moved code.

The mlx5 infiniband conflict resolution was quite non-trivial,
the RDMA tree's merge commit was used as a guide here, and
here are their notes:

====================

    Due to bug fixes found by the syzkaller bot and taken into the for-rc
    branch after development for the 4.17 merge window had already started
    being taken into the for-next branch, there were fairly non-trivial
    merge issues that would need to be resolved between the for-rc branch
    and the for-next branch.  This merge resolves those conflicts and
    provides a unified base upon which ongoing development for 4.17 can
    be based.

    Conflicts:
            drivers/infiniband/hw/mlx5/main.c - Commit 42cea83f95
            (IB/mlx5: Fix cleanup order on unload) added to for-rc and
            commit b5ca15ad7e (IB/mlx5: Add proper representors support)
            add as part of the devel cycle both needed to modify the
            init/de-init functions used by mlx5.  To support the new
            representors, the new functions added by the cleanup patch
            needed to be made non-static, and the init/de-init list
            added by the representors patch needed to be modified to
            match the init/de-init list changes made by the cleanup
            patch.
    Updates:
            drivers/infiniband/hw/mlx5/mlx5_ib.h - Update function
            prototypes added by representors patch to reflect new function
            names as changed by cleanup patch
            drivers/infiniband/hw/mlx5/ib_rep.c - Update init/de-init
            stage list to match new order from cleanup patch
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-23 11:31:58 -04:00
Davide Caratti 1f110e7cae net/sched: fix NULL dereference in the error path of tcf_sample_init()
when the following command

 # tc action add action sample rate 100 group 100 index 100

is run for the first time, and psample_group_get(100) fails to create a
new group, tcf_sample_cleanup() calls psample_group_put(NULL), thus
causing the following error:

 BUG: unable to handle kernel NULL pointer dereference at 000000000000001c
 IP: psample_group_put+0x15/0x71 [psample]
 PGD 8000000075775067 P4D 8000000075775067 PUD 7453c067 PMD 0
 Oops: 0002 [#1] SMP PTI
 Modules linked in: act_sample(E) psample ip6table_filter ip6_tables iptable_filter binfmt_misc ext4 snd_hda_codec_generic snd_hda_intel snd_hda_codec snd_hda_core mbcache jbd2 crct10dif_pclmul snd_hwdep crc32_pclmul snd_seq ghash_clmulni_intel pcbc snd_seq_device snd_pcm aesni_intel crypto_simd snd_timer glue_helper snd cryptd joydev pcspkr i2c_piix4 soundcore virtio_balloon nfsd auth_rpcgss nfs_acl lockd grace sunrpc ip_tables xfs libcrc32c ata_generic pata_acpi qxl drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops ttm drm virtio_net ata_piix virtio_console virtio_blk libata serio_raw crc32c_intel virtio_pci i2c_core virtio_ring virtio floppy dm_mirror dm_region_hash dm_log dm_mod [last unloaded: act_tunnel_key]
 CPU: 2 PID: 5740 Comm: tc Tainted: G            E    4.16.0-rc4.act_vlan.orig+ #403
 Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
 RIP: 0010:psample_group_put+0x15/0x71 [psample]
 RSP: 0018:ffffb8a80032f7d0 EFLAGS: 00010246
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000024
 RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffffffffc06d93c0
 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000044
 R10: 00000000bd003000 R11: ffff979fba04aa59 R12: 0000000000000000
 R13: 0000000000000000 R14: 0000000000000000 R15: ffff979fbba3f22c
 FS:  00007f7638112740(0000) GS:ffff979fbfd00000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 000000000000001c CR3: 00000000734ea001 CR4: 00000000001606e0
 Call Trace:
  __tcf_idr_release+0x79/0xf0
  tcf_sample_init+0x125/0x1d0 [act_sample]
  tcf_action_init_1+0x2cc/0x430
  tcf_action_init+0xd3/0x1b0
  tc_ctl_action+0x18b/0x240
  rtnetlink_rcv_msg+0x29c/0x310
  ? _cond_resched+0x15/0x30
  ? __kmalloc_node_track_caller+0x1b9/0x270
  ? rtnl_calcit.isra.28+0x100/0x100
  netlink_rcv_skb+0xd2/0x110
  netlink_unicast+0x17c/0x230
  netlink_sendmsg+0x2cd/0x3c0
  sock_sendmsg+0x30/0x40
  ___sys_sendmsg+0x27a/0x290
  ? filemap_map_pages+0x34a/0x3a0
  ? __handle_mm_fault+0xbfd/0xe20
  __sys_sendmsg+0x51/0x90
  do_syscall_64+0x6e/0x1a0
  entry_SYSCALL_64_after_hwframe+0x3d/0xa2
 RIP: 0033:0x7f7637523ba0
 RSP: 002b:00007fff0473ef58 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
 RAX: ffffffffffffffda RBX: 00007fff0473f080 RCX: 00007f7637523ba0
 RDX: 0000000000000000 RSI: 00007fff0473efd0 RDI: 0000000000000003
 RBP: 000000005aaaac80 R08: 0000000000000002 R09: 0000000000000000
 R10: 00007fff0473e9e0 R11: 0000000000000246 R12: 0000000000000000
 R13: 00007fff0473f094 R14: 0000000000000001 R15: 0000000000669f60
 Code: be 02 00 00 00 48 89 df e8 a9 fe ff ff e9 7c ff ff ff 0f 1f 40 00 0f 1f 44 00 00 53 48 89 fb 48 c7 c7 c0 93 6d c0 e8 db 20 8c ef <83> 6b 1c 01 74 10 48 c7 c7 c0 93 6d c0 ff 14 25 e8 83 83 b0 5b
 RIP: psample_group_put+0x15/0x71 [psample] RSP: ffffb8a80032f7d0
 CR2: 000000000000001c

Fix it in tcf_sample_cleanup(), ensuring that calls to psample_group_put(p)
are done only when p is not NULL.

Fixes: cadb9c9fdb ("net/sched: act_sample: Fix error path in init")
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-17 19:53:28 -04:00
Kirill Tkhai 685ecfb198 net: Convert tc_action_net_init() and tc_action_net_exit() based pernet_operations
These pernet_operations are from net/sched directory, and they call only
tc_action_net_init() and tc_action_net_exit():

bpf_net_ops
connmark_net_ops
csum_net_ops
gact_net_ops
ife_net_ops
ipt_net_ops
xt_net_ops
mirred_net_ops
nat_net_ops
pedit_net_ops
police_net_ops
sample_net_ops
simp_net_ops
skbedit_net_ops
skbmod_net_ops
tunnel_key_net_ops
vlan_net_ops

1)tc_action_net_init() just allocates and initializes per-net memory.
2)There should not be in-flight packets at the time of tc_action_net_exit()
call, or another pernet_operations send packets to dying net (except
netlink). So, it seems they can be marked as async.

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-27 11:01:36 -05:00
Alexander Aring b36201455a net: sched: act: handle extack in tcf_generic_walker
This patch adds extack handling for a common used TC act function
"tcf_generic_walker()" to add an extack message on failures.
The tcf_generic_walker() function can fail if get a invalid command
different than DEL and GET. The naming "action" here is wrong, the
correct naming would be command.

Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-16 16:05:50 -05:00
Alexander Aring 417801055b net: sched: act: add extack for walk callback
This patch adds extack support for act walker callback api. This
prepares to handle extack support inside each specific act
implementation.

Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-16 16:05:50 -05:00
Alexander Aring 331a9295de net: sched: act: add extack for lookup callback
This patch adds extack support for act lookup callback api. This
prepares to handle extack support inside each specific act
implementation.

Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-16 16:05:03 -05:00
Alexander Aring 589dad6d71 net: sched: act: add extack to init callback
This patch adds extack support for act init callback api. This
prepares to handle extack support inside each specific act
implementation.

Based on work by David Ahern <dsahern@gmail.com>

Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-16 16:05:03 -05:00
Cong Wang 039af9c66b net_sched: switch to exit_batch for action pernet ops
Since we now hold RTNL lock in tc_action_net_exit(), it is good to
batch them to speedup tc action dismantle.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-13 13:58:41 -05:00
Cong Wang 9a63b255df net_sched: remove unused parameter from act cleanup ops
No one actually uses it.

Cc: Jiri Pirko <jiri@mellanox.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-05 18:07:58 -05:00
Cong Wang 90a6ec8535 act_sample: get rid of tcf_sample_cleanup_rcu()
Similar to commit d7fb60b9ca ("net_sched: get rid of tcfa_rcu"),
TC actions don't need to respect RCU grace period, because it
is either just detached from tc filter (standalone case) or
it is removed together with tc filter (bound case) in which case
RCU grace period is already respected at filter layer.

Fixes: 5c5670fae4 ("net/sched: Introduce sample tc action")
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Cc: Yotam Gigi <yotamg@mellanox.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>
2017-11-30 10:19:17 -05:00
Cong Wang c7e460ce55 Revert "net_sched: hold netns refcnt for each action"
This reverts commit ceffcc5e25.
If we hold that refcnt, the netns can never be destroyed until
all actions are destroyed by user, this breaks our netns design
which we expect all actions are destroyed when we destroy the
whole netns.

Cc: Lucas Bates <lucasb@mojatatu.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-09 10:03:09 +09:00
Cong Wang ceffcc5e25 net_sched: hold netns refcnt for each action
TC actions have been destroyed asynchronously for a long time,
previously in a RCU callback and now in a workqueue. If we
don't hold a refcnt for its netns, we could use the per netns
data structure, struct tcf_idrinfo, after it has been freed by
netns workqueue.

Hold refcnt to ensure netns destroy happens after all actions
are gone.

Fixes: ddf97ccdd7 ("net_sched: add network namespace support for tc actions")
Reported-by: Lucas Bates <lucasb@mojatatu.com>
Tested-by: Lucas Bates <lucasb@mojatatu.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-03 10:30:38 +09:00