Commit Graph

289 Commits

Author SHA1 Message Date
Azeem Shaikh
989b52cdc8 net: sched: Replace strlcpy with strscpy
strlcpy() reads the entire source buffer first.
This read may exceed the destination size limit.
This is both inefficient and can lead to linear read
overflows if a source string is not NUL-terminated [1].
In an effort to remove strlcpy() completely [2], replace
strlcpy() here with strscpy().

Direct replacement is safe here since return value of -errno
is used to check for truncation instead of sizeof(dest).

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
[2] https://github.com/KSPP/linux/issues/89

Signed-off-by: Azeem Shaikh <azeemshaikh38@gmail.com>
Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-07-10 08:23:53 +01:00
Pedro Tammela
fcb3a4653b net/sched: act_api: use the correct TCA_ACT attributes in dump
4 places in the act api code are using 'TCA_' definitions where they
should be using 'TCA_ACT_', which is confusing for the reader, although
functionally they are equivalent.

Cc: Hangbin Liu <haliu@redhat.com>
Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
Acked-by: Hangbin Liu <haliu@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-23 08:39:08 +00:00
Hangbin Liu
2f59823fe6 net/sched: act_api: add specific EXT_WARN_MSG for tc action
In my previous commit 0349b8779c ("sched: add new attr TCA_EXT_WARN_MSG
to report tc extact message") I didn't notice the tc action use different
enum with filter. So we can't use TCA_EXT_WARN_MSG directly for tc action.
Let's add a TCA_ROOT_EXT_WARN_MSG for tc action specifically and put this
param before going to the TCA_ACT_TAB nest.

Fixes: 0349b8779c ("sched: add new attr TCA_EXT_WARN_MSG to report tc extact message")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-16 21:25:45 -07:00
Hangbin Liu
8de2bd0243 Revert "net/sched: act_api: move TCA_EXT_WARN_MSG to the correct hierarchy"
This reverts commit 923b2e30dc.

This is not a correct fix as TCA_EXT_WARN_MSG is not a hierarchy to
TCA_ACT_TAB. I didn't notice the TC actions use different enum when adding
TCA_EXT_WARN_MSG. To fix the difference I will add a new WARN enum in
TCA_ROOT_MAX as Jamal suggested.

Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-16 21:25:45 -07:00
Pedro Tammela
923b2e30dc net/sched: act_api: move TCA_EXT_WARN_MSG to the correct hierarchy
TCA_EXT_WARN_MSG is currently sitting outside of the expected hierarchy
for the tc actions code. It should sit within TCA_ACT_TAB.

Fixes: 0349b8779c ("sched: add new attr TCA_EXT_WARN_MSG to report tc extact message")
Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-02-27 12:16:34 +00:00
Paul Blakey
80cd22c35c net/sched: cls_api: Support hardware miss to tc action
For drivers to support partial offload of a filter's action list,
add support for action miss to specify an action instance to
continue from in sw.

CT action in particular can't be fully offloaded, as new connections
need to be handled in software. This imposes other limitations on
the actions that can be offloaded together with the CT action, such
as packet modifications.

Assign each action on a filter's action list a unique miss_cookie
which drivers can then use to fill action_miss part of the tc skb
extension. On getting back this miss_cookie, find the action
instance with relevant cookie and continue classifying from there.

Signed-off-by: Paul Blakey <paulb@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-02-20 16:46:10 -08:00
Paul Blakey
db4b49025c net/sched: Rename user cookie and act cookie
struct tc_action->act_cookie is a user defined cookie,
and the related struct flow_action_entry->act_cookie is
used as an handle similar to struct flow_cls_offload->cookie.

Rename tc_action->act_cookie to user_cookie, and
flow_action_entry->act_cookie to cookie so their names
would better fit their usage.

Signed-off-by: Paul Blakey <paulb@nvidia.com>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-02-20 16:46:10 -08:00
Oz Shlomo
5246c896b8 net/sched: support per action hw stats
There are currently two mechanisms for populating hardware stats:
1. Using flow_offload api to query the flow's statistics.
   The api assumes that the same stats values apply to all
   the flow's actions.
   This assumption breaks when action drops or jumps over following
   actions.
2. Using hw_action api to query specific action stats via a driver
   callback method. This api assures the correct action stats for
   the offloaded action, however, it does not apply to the rest of the
   actions in the flow's actions array.

Extend the flow_offload stats callback to indicate that a per action
stats update is required.
Use the existing flow_offload_action api to query the action's hw stats.
In addition, currently the tc action stats utility only updates hw actions.
Reuse the existing action stats cb infrastructure to query any action
stats.

Signed-off-by: Oz Shlomo <ozsh@nvidia.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-02-14 11:00:01 +01:00
Oz Shlomo
d307b2c6f9 net/sched: introduce flow_offload action cookie
Currently a hardware action is uniquely identified by the <id, hw_index>
tuple. However, the id is set by the flow_act_setup callback and tc core
cannot enforce this, and it is possible that a future change could break
this. In addition, <id, hw_index> are not unique across network namespaces.

Uniquely identify the action by setting an action cookie by the tc core.
Use the unique action cookie to query the action's hardware stats.

Signed-off-by: Oz Shlomo <ozsh@nvidia.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-02-14 11:00:01 +01:00
Oz Shlomo
8f2ca70c07 net/sched: optimize action stats api calls
Currently the hw action stats update is called from tcf_exts_hw_stats_update,
when a tc filter is dumped, and from tcf_action_copy_stats, when a hw
action is dumped.
However, the tcf_action_copy_stats is also called from tcf_action_dump.
As such, the hw action stats update cb is called 3 times for every
tc flower filter dump.

Move the tc action hw stats update from tcf_action_copy_stats to
tcf_dump_walker to update the hw action stats when tc action is dumped.

Signed-off-by: Oz Shlomo <ozsh@nvidia.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-02-14 11:00:00 +01:00
Hangbin Liu
0349b8779c sched: add new attr TCA_EXT_WARN_MSG to report tc extact message
We will report extack message if there is an error via netlink_ack(). But
if the rule is not to be exclusively executed by the hardware, extack is not
passed along and offloading failures don't get logged.

In commit 81c7288b17 ("sched: cls: enable verbose logging") Marcelo
made cls could log verbose info for offloading failures, which helps
improving Open vSwitch debuggability when using flower offloading.

It would also be helpful if userspace monitor tools, like "tc monitor",
could log this kind of message, as it doesn't require vswitchd log level
adjusment. Let's add a new tc attributes to report the extack message so
the monitor program could receive the failures. e.g.

  # tc monitor
  added chain dev enp3s0f1np1 parent ffff: chain 0
  added filter dev enp3s0f1np1 ingress protocol all pref 49152 flower chain 0 handle 0x1
    ct_state +trk+new
    not_in_hw
          action order 1: gact action drop
           random type none pass val 0
           index 1 ref 1 bind 1

  Warning: mlx5_core: matching on ct_state +new isn't supported.

In this patch I only report the extack message on add/del operations.
It doesn't look like we need to report the extack message on get/dump
operations.

Note this message not only reporte to multicast groups, it could also
be reported unicast, which may affect the current usersapce tool's behaivor.

Suggested-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://lore.kernel.org/r/20230113034353.2766735-1-liuhangbin@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-01-17 09:38:33 +01:00
Pedro Tammela
871cf386dd net/sched: avoid indirect act functions on retpoline kernels
Expose the necessary tc act functions and wire up act_api to use
direct calls in retpoline kernels.

Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Reviewed-by: Victor Nogueira <victor@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-12-09 09:18:07 +00:00
Zhengchao Shao
fae52d9323 net: sched: act_api: implement generic walker and search for tc action
Being able to get tc_action_net by using net_id stored in tc_action_ops
and execute the generic walk/search function, add __tcf_generic_walker()
and __tcf_idr_search() helpers.

Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-09-09 08:24:41 +01:00
Victor Nogueira
76b39b9438 net/sched: act_api: Notify user space if any actions were flushed before error
If during an action flush operation one of the actions is still being
referenced, the flush operation is aborted and the kernel returns to
user space with an error. However, if the kernel was able to flush, for
example, 3 actions and failed on the fourth, the kernel will not notify
user space that it deleted 3 actions before failing.

This patch fixes that behaviour by notifying user space of how many
actions were deleted before flush failed and by setting extack with a
message describing what happened.

Fixes: 55334a5db5 ("net_sched: act: refuse to remove bound action outside")
Signed-off-by: Victor Nogueira <victor@mojatatu.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-06-27 21:51:23 -07:00
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
d922a99b96 flow_offload: improve extack msg for user when adding invalid filter
Add extack message to return exact message to user when adding invalid
filter with conflict flags for TC action.

In previous implement we just return EINVAL which is confusing for user.

Signed-off-by: Baowen Zheng <baowen.zheng@corigine.com>
Reviewed-by: Roi Dayan <roid@nvidia.com>
Link: https://lore.kernel.org/r/1646191769-17761-1-git-send-email-baowen.zheng@corigine.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-02 22:16:10 -08:00
Wan Jiabing
ecf4a24cf9 net: sched: avoid newline at end of message in NL_SET_ERR_MSG_MOD
Fix following coccicheck warning:
./net/sched/act_api.c:277:7-49: WARNING avoid newline at end of message
in NL_SET_ERR_MSG_MOD

Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-23 12:45:44 +00:00
Eric Dumazet
5740d06890 net: sched: limit TC_ACT_REPEAT loops
We have been living dangerously, at the mercy of malicious users,
abusing TC_ACT_REPEAT, as shown by this syzpot report [1].

Add an arbitrary limit (32) to the number of times an action can
return TC_ACT_REPEAT.

v2: switch the limit to 32 instead of 10.
    Use net_warn_ratelimited() instead of pr_err_once().

[1] (C repro available on demand)

rcu: INFO: rcu_preempt self-detected stall on CPU
rcu:    1-...!: (10500 ticks this GP) idle=021/1/0x4000000000000000 softirq=5592/5592 fqs=0
        (t=10502 jiffies g=5305 q=190)
rcu: rcu_preempt kthread timer wakeup didn't happen for 10502 jiffies! g5305 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu:    Possible timer handling issue on cpu=0 timer-softirq=3527
rcu: rcu_preempt kthread starved for 10505 jiffies! g5305 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0
rcu:    Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:I stack:29344 pid:   14 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:4986 [inline]
 __schedule+0xab2/0x4db0 kernel/sched/core.c:6295
 schedule+0xd2/0x260 kernel/sched/core.c:6368
 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881
 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1963
 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2136
 kthread+0x2e9/0x3a0 kernel/kthread.c:377
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 3646 Comm: syz-executor358 Not tainted 5.17.0-rc3-syzkaller-00149-gbf8e59fd315f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:rep_nop arch/x86/include/asm/vdso/processor.h:13 [inline]
RIP: 0010:cpu_relax arch/x86/include/asm/vdso/processor.h:18 [inline]
RIP: 0010:pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:437 [inline]
RIP: 0010:__pv_queued_spin_lock_slowpath+0x3b8/0xb40 kernel/locking/qspinlock.c:508
Code: 48 89 eb c6 45 01 01 41 bc 00 80 00 00 48 c1 e9 03 83 e3 07 41 be 01 00 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8d 2c 01 eb 0c <f3> 90 41 83 ec 01 0f 84 72 04 00 00 41 0f b6 45 00 38 d8 7f 08 84
RSP: 0018:ffffc9000283f1b0 EFLAGS: 00000206
RAX: 0000000000000003 RBX: 0000000000000000 RCX: 1ffff1100fc0071e
RDX: 0000000000000001 RSI: 0000000000000201 RDI: 0000000000000000
RBP: ffff88807e0038f0 R08: 0000000000000001 R09: ffffffff8ffbf9ff
R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000004c1e
R13: ffffed100fc0071e R14: 0000000000000001 R15: ffff8880b9c3aa80
FS:  00005555562bf300(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffdbfef12b8 CR3: 00000000723c2000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:591 [inline]
 queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:85 [inline]
 do_raw_spin_lock+0x200/0x2b0 kernel/locking/spinlock_debug.c:115
 spin_lock_bh include/linux/spinlock.h:354 [inline]
 sch_tree_lock include/net/sch_generic.h:610 [inline]
 sch_tree_lock include/net/sch_generic.h:605 [inline]
 prio_tune+0x3b9/0xb50 net/sched/sch_prio.c:211
 prio_init+0x5c/0x80 net/sched/sch_prio.c:244
 qdisc_create.constprop.0+0x44a/0x10f0 net/sched/sch_api.c:1253
 tc_modify_qdisc+0x4c5/0x1980 net/sched/sch_api.c:1660
 rtnetlink_rcv_msg+0x413/0xb80 net/core/rtnetlink.c:5594
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2494
 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
 netlink_unicast+0x539/0x7e0 net/netlink/af_netlink.c:1343
 netlink_sendmsg+0x904/0xe00 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:705 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:725
 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2413
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2467
 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2496
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f7ee98aae99
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 41 15 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffdbfef12d8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007ffdbfef1300 RCX: 00007f7ee98aae99
RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000003
RBP: 0000000000000000 R08: 000000000000000d R09: 000000000000000d
R10: 000000000000000d R11: 0000000000000246 R12: 00007ffdbfef12f0
R13: 00000000000f4240 R14: 000000000004ca47 R15: 00007ffdbfef12e4
 </TASK>
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 2.293 msecs
NMI backtrace for cpu 1
CPU: 1 PID: 3260 Comm: kworker/1:3 Not tainted 5.17.0-rc3-syzkaller-00149-gbf8e59fd315f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: mld mld_ifc_work
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x25e/0x3f0 kernel/rcu/tree_stall.h:343
 print_cpu_stall kernel/rcu/tree_stall.h:604 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:688 [inline]
 rcu_pending kernel/rcu/tree.c:3919 [inline]
 rcu_sched_clock_irq.cold+0x5c/0x759 kernel/rcu/tree.c:2617
 update_process_times+0x16d/0x200 kernel/time/timer.c:1785
 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226
 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1428
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x1c0/0xe50 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline]
 __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103
 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0xc/0x70 kernel/kcov.c:286
Code: 00 00 00 48 89 7c 30 e8 48 89 4c 30 f0 4c 89 54 d8 20 48 89 10 5b c3 0f 1f 80 00 00 00 00 41 89 f8 bf 03 00 00 00 4c 8b 14 24 <89> f1 65 48 8b 34 25 00 70 02 00 e8 14 f9 ff ff 84 c0 74 4b 48 8b
RSP: 0018:ffffc90002c5eea8 EFLAGS: 00000246
RAX: 0000000000000007 RBX: ffff88801c625800 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: ffff8880137d3100 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff874fcd88 R11: 0000000000000000 R12: ffff88801d692dc0
R13: ffff8880137d3104 R14: 0000000000000000 R15: ffff88801d692de8
 tcf_police_act+0x358/0x11d0 net/sched/act_police.c:256
 tcf_action_exec net/sched/act_api.c:1049 [inline]
 tcf_action_exec+0x1a6/0x530 net/sched/act_api.c:1026
 tcf_exts_exec include/net/pkt_cls.h:326 [inline]
 route4_classify+0xef0/0x1400 net/sched/cls_route.c:179
 __tcf_classify net/sched/cls_api.c:1549 [inline]
 tcf_classify+0x3e8/0x9d0 net/sched/cls_api.c:1615
 prio_classify net/sched/sch_prio.c:42 [inline]
 prio_enqueue+0x3a7/0x790 net/sched/sch_prio.c:75
 dev_qdisc_enqueue+0x40/0x300 net/core/dev.c:3668
 __dev_xmit_skb net/core/dev.c:3756 [inline]
 __dev_queue_xmit+0x1f61/0x3660 net/core/dev.c:4081
 neigh_hh_output include/net/neighbour.h:533 [inline]
 neigh_output include/net/neighbour.h:547 [inline]
 ip_finish_output2+0x14dc/0x2170 net/ipv4/ip_output.c:228
 __ip_finish_output net/ipv4/ip_output.c:306 [inline]
 __ip_finish_output+0x396/0x650 net/ipv4/ip_output.c:288
 ip_finish_output+0x32/0x200 net/ipv4/ip_output.c:316
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip_output+0x196/0x310 net/ipv4/ip_output.c:430
 dst_output include/net/dst.h:451 [inline]
 ip_local_out+0xaf/0x1a0 net/ipv4/ip_output.c:126
 iptunnel_xmit+0x628/0xa50 net/ipv4/ip_tunnel_core.c:82
 geneve_xmit_skb drivers/net/geneve.c:966 [inline]
 geneve_xmit+0x10c8/0x3530 drivers/net/geneve.c:1077
 __netdev_start_xmit include/linux/netdevice.h:4683 [inline]
 netdev_start_xmit include/linux/netdevice.h:4697 [inline]
 xmit_one net/core/dev.c:3473 [inline]
 dev_hard_start_xmit+0x1eb/0x920 net/core/dev.c:3489
 __dev_queue_xmit+0x2985/0x3660 net/core/dev.c:4116
 neigh_hh_output include/net/neighbour.h:533 [inline]
 neigh_output include/net/neighbour.h:547 [inline]
 ip6_finish_output2+0xf7a/0x14f0 net/ipv6/ip6_output.c:126
 __ip6_finish_output net/ipv6/ip6_output.c:191 [inline]
 __ip6_finish_output+0x61e/0xe90 net/ipv6/ip6_output.c:170
 ip6_finish_output+0x32/0x200 net/ipv6/ip6_output.c:201
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip6_output+0x1e4/0x530 net/ipv6/ip6_output.c:224
 dst_output include/net/dst.h:451 [inline]
 NF_HOOK include/linux/netfilter.h:307 [inline]
 NF_HOOK include/linux/netfilter.h:301 [inline]
 mld_sendpack+0x9a3/0xe40 net/ipv6/mcast.c:1826
 mld_send_cr net/ipv6/mcast.c:2127 [inline]
 mld_ifc_work+0x71c/0xdc0 net/ipv6/mcast.c:2659
 process_one_work+0x9ac/0x1650 kernel/workqueue.c:2307
 worker_thread+0x657/0x1110 kernel/workqueue.c:2454
 kthread+0x2e9/0x3a0 kernel/kthread.c:377
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
----------------
Code disassembly (best guess):
   0:   48 89 eb                mov    %rbp,%rbx
   3:   c6 45 01 01             movb   $0x1,0x1(%rbp)
   7:   41 bc 00 80 00 00       mov    $0x8000,%r12d
   d:   48 c1 e9 03             shr    $0x3,%rcx
  11:   83 e3 07                and    $0x7,%ebx
  14:   41 be 01 00 00 00       mov    $0x1,%r14d
  1a:   48 b8 00 00 00 00 00    movabs $0xdffffc0000000000,%rax
  21:   fc ff df
  24:   4c 8d 2c 01             lea    (%rcx,%rax,1),%r13
  28:   eb 0c                   jmp    0x36
* 2a:   f3 90                   pause <-- trapping instruction
  2c:   41 83 ec 01             sub    $0x1,%r12d
  30:   0f 84 72 04 00 00       je     0x4a8
  36:   41 0f b6 45 00          movzbl 0x0(%r13),%eax
  3b:   38 d8                   cmp    %bl,%al
  3d:   7f 08                   jg     0x47
  3f:   84                      .byte 0x84

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Reported-by: syzbot <syzkaller@googlegroups.com>
Link: https://lore.kernel.org/r/20220215235305.3272331-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-16 20:45:55 -08:00
Baowen Zheng
963178a063 flow_offload: fix suspicious RCU usage when offloading tc action
Fix suspicious rcu_dereference_protected() usage when offloading tc action.

We should hold tcfa_lock to offload tc action in action initiation.

Without these changes, the following warning will be observed:

WARNING: suspicious RCU usage
5.16.0-rc5-net-next-01504-g7d1f236dcffa-dirty #50 Tainted: G          I
-----------------------------
include/net/tc_act/tc_tunnel_key.h:33 suspicious rcu_dereference_protected() usage!
1 lock held by tc/12108:
CPU: 4 PID: 12108 Comm: tc Tainted: G
Hardware name: Dell Inc. PowerEdge R740/07WCGN, BIOS 1.6.11 11/20/2018
Call Trace:
<TASK>
dump_stack_lvl+0x49/0x5e
dump_stack+0x10/0x12
lockdep_rcu_suspicious+0xed/0xf8
tcf_tunnel_key_offload_act_setup+0x1de/0x300 [act_tunnel_key]
tcf_action_offload_add_ex+0xc0/0x1f0
tcf_action_init+0x26a/0x2f0
tcf_action_add+0xa9/0x1f0
tc_ctl_action+0xfb/0x170
rtnetlink_rcv_msg+0x169/0x510
? sched_clock+0x9/0x10
? rtnl_newlink+0x70/0x70
netlink_rcv_skb+0x55/0x100
rtnetlink_rcv+0x15/0x20
netlink_unicast+0x1a8/0x270
netlink_sendmsg+0x245/0x490
sock_sendmsg+0x65/0x70
____sys_sendmsg+0x219/0x260
? __import_iovec+0x2c/0x150
___sys_sendmsg+0xb7/0x100
? __lock_acquire+0x3d5/0x1f40
? __this_cpu_preempt_check+0x13/0x20
? lock_is_held_type+0xe4/0x140
? sched_clock+0x9/0x10
? ktime_get_coarse_real_ts64+0xbe/0xd0
? __this_cpu_preempt_check+0x13/0x20
? lockdep_hardirqs_on+0x7e/0x100
? ktime_get_coarse_real_ts64+0xbe/0xd0
? trace_hardirqs_on+0x2a/0xf0
__sys_sendmsg+0x5a/0xa0
? syscall_trace_enter.constprop.0+0x1dd/0x220
__x64_sys_sendmsg+0x1f/0x30
do_syscall_64+0x3b/0x90
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f4db7bb7a60

Fixes: 8cbfe939ab ("flow_offload: allow user to offload tc action to net device")
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Baowen Zheng <baowen.zheng@corigine.com>
Signed-off-by: Louis Peens <louis.peens@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-23 11:17:00 +00:00
Baowen Zheng
c86e0209dc flow_offload: validate flags of filter and actions
Add process to validate flags of filter and actions when adding
a tc filter.

We need to prevent adding filter with flags conflicts with its actions.

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 14:08:48 +00:00
Baowen Zheng
13926d19a1 flow_offload: add reoffload process to update hw_count
Add reoffload process to update hw_count when driver
is inserted or removed.

We will delete the action if it is with skip_sw flag and
not offloaded to any hardware in reoffload process.

When reoffloading actions, we still offload the actions
that are added independent of filters.

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
e8cb5bcf6e net: sched: save full flags for tc action
Save full action flags and return user flags when return flags to
user space.

Save full action flags to distinguish if the action is created
independent from classifier.

We made this change mainly for further patch to reoffload tc actions.

Signed-off-by: Baowen Zheng <baowen.zheng@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 14:08:48 +00:00
Baowen Zheng
c7a66f8d8a flow_offload: add process to update action stats from hardware
When collecting stats for actions update them using both
hardware and software counters.

Stats update process should not run in context of preempt_disable.

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
7adc576512 flow_offload: add skip_hw and skip_sw to control if offload the action
We add skip_hw and skip_sw for user to control if offload the action
to hardware.

We also add in_hw_count for user to indicate if the action is offloaded
to any hardware.

Signed-off-by: Baowen Zheng <baowen.zheng@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 14:08:48 +00:00
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
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
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
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
Yajun Deng
f79a3bcb1a net/sched: Remove unnecessary if statement
It has been deal with the 'if (err' statement in rtnetlink_send()
and rtnl_unicast(). so remove unnecessary if statement.

v2: use the raw name rtnetlink_send().

Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-16 10:46:35 -07:00
Yang Yingliang
55d96f72e8 net: sched: fix error return code in tcf_del_walker()
When nla_put_u32() fails, 'ret' could be 0, it should
return error code in tcf_del_walker().

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-17 11:36:18 -07:00
Vlad Buslov
b3650bf76a net: sched: fix err handler in tcf_action_init()
With recent changes that separated action module load from action
initialization tcf_action_init() function error handling code was modified
to manually release the loaded modules if loading/initialization of any
further action in same batch failed. For the case when all modules
successfully loaded and some of the actions were initialized before one of
them failed in init handler. In this case for all previous actions the
module will be released twice by the error handler: First time by the loop
that manually calls module_put() for all ops, and second time by the action
destroy code that puts the module after destroying the action.

Reproduction:

$ sudo tc actions add action simple sdata \"2\" index 2
$ sudo tc actions add action simple sdata \"1\" index 1 \
                      action simple sdata \"2\" index 2
RTNETLINK answers: File exists
We have an error talking to the kernel
$ sudo tc actions ls action simple
total acts 1

        action order 0: Simple <"2">
         index 2 ref 1 bind 0
$ sudo tc actions flush action simple
$ sudo tc actions ls action simple
$ sudo tc actions add action simple sdata \"2\" index 2
Error: Failed to load TC action module.
We have an error talking to the kernel
$ lsmod | grep simple
act_simple             20480  -1

Fix the issue by modifying module reference counting handling in action
initialization code:

- Get module reference in tcf_idr_create() and put it in tcf_idr_release()
instead of taking over the reference held by the caller.

- Modify users of tcf_action_init_1() to always release the module
reference which they obtain before calling init function instead of
assuming that created action takes over the reference.

- Finally, modify tcf_action_init_1() to not release the module reference
when overwriting existing action as this is no longer necessary since both
upper and lower layers obtain and manage their own module references
independently.

Fixes: d349f99768 ("net_sched: fix RTNL deadlock again caused by request_module()")
Suggested-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-08 13:47:33 -07:00
Vlad Buslov
87c750e8c3 net: sched: fix action overwrite reference counting
Action init code increments reference counter when it changes an action.
This is the desired behavior for cls API which needs to obtain action
reference for every classifier that points to action. However, act API just
needs to change the action and releases the reference before returning.
This sequence breaks when the requested action doesn't exist, which causes
act API init code to create new action with specified index, but action is
still released before returning and is deleted (unless it was referenced
concurrently by cls API).

Reproduction:

$ sudo tc actions ls action gact
$ sudo tc actions change action gact drop index 1
$ sudo tc actions ls action gact

Extend tcf_action_init() to accept 'init_res' array and initialize it with
action->ops->init() result. In tcf_action_add() remove pointers to created
actions from actions array before passing it to tcf_action_put_many().

Fixes: cae422f379 ("net: sched: use reference counting action init")
Reported-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-08 13:47:33 -07:00
Vlad Buslov
4ba86128ba Revert "net: sched: bump refcount for new action in ACT replace mode"
This reverts commit 6855e8213e.

Following commit in series fixes the issue without introducing regression
in error rollback of tcf_action_destroy().

Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-08 13:47:33 -07:00
Kumar Kartikeya Dwivedi
6855e8213e net: sched: bump refcount for new action in ACT replace mode
Currently, action creation using ACT API in replace mode is buggy.
When invoking for non-existent action index 42,

	tc action replace action bpf obj foo.o sec <xyz> index 42

kernel creates the action, fills up the netlink response, and then just
deletes the action after notifying userspace.

	tc action show action bpf

doesn't list the action.

This happens due to the following sequence when ovr = 1 (replace mode)
is enabled:

tcf_idr_check_alloc is used to atomically check and either obtain
reference for existing action at index, or reserve the index slot using
a dummy entry (ERR_PTR(-EBUSY)).

This is necessary as pointers to these actions will be held after
dropping the idrinfo lock, so bumping the reference count is necessary
as we need to insert the actions, and notify userspace by dumping their
attributes. Finally, we drop the reference we took using the
tcf_action_put_many call in tcf_action_add. However, for the case where
a new action is created due to free index, its refcount remains one.
This when paired with the put_many call leads to the kernel setting up
the action, notifying userspace of its creation, and then tearing it
down. For existing actions, the refcount is still held so they remain
unaffected.

Fortunately due to rtnl_lock serialization requirement, such an action
with refcount == 1 will not be concurrently deleted by anything else, at
best CLS API can move its refcount up and down by binding to it after it
has been published from tcf_idr_insert_many. Since refcount is atleast
one until put_many call, CLS API cannot delete it. Also __tcf_action_put
release path already ensures deterministic outcome (either new action
will be created or existing action will be reused in case CLS API tries
to bind to action concurrently) due to idr lock serialization.

We fix this by making refcount of newly created actions as 2 in ACT API
replace mode. A relaxed store will suffice as visibility is ensured only
after the tcf_idr_insert_many call.

Note that in case of creation or overwriting using CLS API only (i.e.
bind = 1), overwriting existing action object is not allowed, and any
such request is silently ignored (without error).

The refcount bump that occurs in tcf_idr_check_alloc call there for
existing action will pair with tcf_exts_destroy call made from the
owner module for the same action. In case of action creation, there
is no existing action, so no tcf_exts_destroy callback happens.

This means no code changes for CLS API.

Fixes: cae422f379 ("net: sched: use reference counting action init")
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-30 13:18:02 -07:00
David S. Miller
d489ded1a3 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-02-16 17:51:13 -08:00
Vlad Buslov
396d7f23ad net: sched: fix police ext initialization
When police action is created by cls API tcf_exts_validate() first
conditional that calls tcf_action_init_1() directly, the action idr is not
updated according to latest changes in action API that require caller to
commit newly created action to idr with tcf_idr_insert_many(). This results
such action not being accessible through act API and causes crash reported
by syzbot:

==================================================================
BUG: KASAN: null-ptr-deref in instrument_atomic_read include/linux/instrumented.h:71 [inline]
BUG: KASAN: null-ptr-deref in atomic_read include/asm-generic/atomic-instrumented.h:27 [inline]
BUG: KASAN: null-ptr-deref in __tcf_idr_release net/sched/act_api.c:178 [inline]
BUG: KASAN: null-ptr-deref in tcf_idrinfo_destroy+0x129/0x1d0 net/sched/act_api.c:598
Read of size 4 at addr 0000000000000010 by task kworker/u4:5/204

CPU: 0 PID: 204 Comm: kworker/u4:5 Not tainted 5.11.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x107/0x163 lib/dump_stack.c:120
 __kasan_report mm/kasan/report.c:400 [inline]
 kasan_report.cold+0x5f/0xd5 mm/kasan/report.c:413
 check_memory_region_inline mm/kasan/generic.c:179 [inline]
 check_memory_region+0x13d/0x180 mm/kasan/generic.c:185
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 atomic_read include/asm-generic/atomic-instrumented.h:27 [inline]
 __tcf_idr_release net/sched/act_api.c:178 [inline]
 tcf_idrinfo_destroy+0x129/0x1d0 net/sched/act_api.c:598
 tc_action_net_exit include/net/act_api.h:151 [inline]
 police_exit_net+0x168/0x360 net/sched/act_police.c:390
 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:190
 cleanup_net+0x4ea/0xb10 net/core/net_namespace.c:604
 process_one_work+0x98d/0x15f0 kernel/workqueue.c:2275
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421
 kthread+0x3b1/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296
==================================================================
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 204 Comm: kworker/u4:5 Tainted: G    B             5.11.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x107/0x163 lib/dump_stack.c:120
 panic+0x306/0x73d kernel/panic.c:231
 end_report+0x58/0x5e mm/kasan/report.c:100
 __kasan_report mm/kasan/report.c:403 [inline]
 kasan_report.cold+0x67/0xd5 mm/kasan/report.c:413
 check_memory_region_inline mm/kasan/generic.c:179 [inline]
 check_memory_region+0x13d/0x180 mm/kasan/generic.c:185
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 atomic_read include/asm-generic/atomic-instrumented.h:27 [inline]
 __tcf_idr_release net/sched/act_api.c:178 [inline]
 tcf_idrinfo_destroy+0x129/0x1d0 net/sched/act_api.c:598
 tc_action_net_exit include/net/act_api.h:151 [inline]
 police_exit_net+0x168/0x360 net/sched/act_police.c:390
 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:190
 cleanup_net+0x4ea/0xb10 net/core/net_namespace.c:604
 process_one_work+0x98d/0x15f0 kernel/workqueue.c:2275
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421
 kthread+0x3b1/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296
Kernel Offset: disabled

Fix the issue by calling tcf_idr_insert_many() after successful action
initialization.

Fixes: 0fedc63fad ("net_sched: commit action insertions together")
Reported-by: syzbot+151e3e714d34ae4ce7e8@syzkaller.appspotmail.com
Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Reviewed-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-02-16 14:59:19 -08:00
Cong Wang
d349f99768 net_sched: fix RTNL deadlock again caused by request_module()
tcf_action_init_1() loads tc action modules automatically with
request_module() after parsing the tc action names, and it drops RTNL
lock and re-holds it before and after request_module(). This causes a
lot of troubles, as discovered by syzbot, because we can be in the
middle of batch initializations when we create an array of tc actions.

One of the problem is deadlock:

CPU 0					CPU 1
rtnl_lock();
for (...) {
  tcf_action_init_1();
    -> rtnl_unlock();
    -> request_module();
				rtnl_lock();
				for (...) {
				  tcf_action_init_1();
				    -> tcf_idr_check_alloc();
				   // Insert one action into idr,
				   // but it is not committed until
				   // tcf_idr_insert_many(), then drop
				   // the RTNL lock in the _next_
				   // iteration
				   -> rtnl_unlock();
    -> rtnl_lock();
    -> a_o->init();
      -> tcf_idr_check_alloc();
      // Now waiting for the same index
      // to be committed
				    -> request_module();
				    -> rtnl_lock()
				    // Now waiting for RTNL lock
				}
				rtnl_unlock();
}
rtnl_unlock();

This is not easy to solve, we can move the request_module() before
this loop and pre-load all the modules we need for this netlink
message and then do the rest initializations. So the loop breaks down
to two now:

        for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
                struct tc_action_ops *a_o;

                a_o = tc_action_load_ops(name, tb[i]...);
                ops[i - 1] = a_o;
        }

        for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
                act = tcf_action_init_1(ops[i - 1]...);
        }

Although this looks serious, it only has been reported by syzbot, so it
seems hard to trigger this by humans. And given the size of this patch,
I'd suggest to make it to net-next and not to backport to stable.

This patch has been tested by syzbot and tested with tdc.py by me.

Fixes: 0fedc63fad ("net_sched: commit action insertions together")
Reported-and-tested-by: syzbot+82752bc5331601cf4899@syzkaller.appspotmail.com
Reported-and-tested-by: syzbot+b3b63b6bff456bd95294@syzkaller.appspotmail.com
Reported-by: syzbot+ba67b12b1ca729912834@syzkaller.appspotmail.com
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Tested-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://lore.kernel.org/r/20210117005657.14810-1-xiyou.wangcong@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-18 20:13:55 -08:00
wenxu
c129412f74 net/sched: sch_frag: add generic packet fragment support.
Currently kernel tc subsystem can do conntrack in cat_ct. But when several
fragment packets go through the act_ct, function tcf_ct_handle_fragments
will defrag the packets to a big one. But the last action will redirect
mirred to a device which maybe lead the reassembly big packet over the mtu
of target device.

This patch add support for a xmit hook to mirred, that gets executed before
xmiting the packet. Then, when act_ct gets loaded, it configs that hook.
The frag xmit hook maybe reused by other modules.

Signed-off-by: wenxu <wenxu@ucloud.cn>
Acked-by: Cong Wang <cong.wang@bytedance.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-27 14:36:02 -08:00
Vlad Buslov
f460019b4c net: sched: alias action flags with TCA_ACT_ prefix
Currently both filter and action flags use same "TCA_" prefix which makes
them hard to distinguish to code and confusing for users. Create aliases
for existing action flags constants with "TCA_ACT_" prefix.

Signed-off-by: Vlad Buslov <vlad@buslov.dev>
Link: https://lore.kernel.org/r/20201124164054.893168-1-vlad@buslov.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-25 12:34:44 -08:00
Francis Laniel
872f690341 treewide: rename nla_strlcpy to nla_strscpy.
Calls to nla_strlcpy are now replaced by calls to nla_strscpy which is the new
name of this function.

Signed-off-by: Francis Laniel <laniel_francis@privacyrequired.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-16 08:08:54 -08:00
Francis Laniel
9ca718743a Modify return value of nla_strlcpy to match that of strscpy.
nla_strlcpy now returns -E2BIG if src was truncated when written to dst.
It also returns this error value if dstsize is 0 or higher than INT_MAX.

For example, if src is "foo\0" and dst is 3 bytes long, the result will be:
1. "foG" after memcpy (G means garbage).
2. "fo\0" after memset.
3. -E2BIG is returned because src was not completely written into dst.

The callers of nla_strlcpy were modified to take into account this modification.

Signed-off-by: Francis Laniel <laniel_francis@privacyrequired.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-16 08:08:54 -08:00
Menglong Dong
e5a4b17da1 net: sched: fix misspellings using misspell-fixer tool
Some typos are found out by misspell-fixer tool:

$ misspell-fixer -rnv ./net/sched/
./net/sched/act_api.c:686
./net/sched/act_bpf.c:68
./net/sched/cls_rsvp.h:241
./net/sched/em_cmp.c:44
./net/sched/sch_pie.c:408

Fix typos found by misspell-fixer.

Signed-off-by: Menglong Dong <dong.menglong@zte.com.cn>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/r/5fa8e9d4.1c69fb81.5d889.5c64@mx.google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-10 17:00:28 -08:00
Vlad Buslov
94f44f2883 net: sched: implement action-specific terse dump
Allow user to request action terse dump with new flag value
TCA_FLAG_TERSE_DUMP. Only output essential action info in terse dump (kind,
stats, index and cookie, if set by the user when creating the action). This
is different from filter terse dump where index is excluded (filter can be
identified by its own handle).

Move tcf_action_dump_terse() function to the beginning of source file in
order to call it from tcf_dump_walker().

Signed-off-by: Vlad Buslov <vlad@buslov.dev>
Suggested-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Link: https://lore.kernel.org/r/20201102201243.287486-1-vlad@buslov.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-05 08:27:43 -08:00
David S. Miller
8b0308fe31 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Rejecting non-native endian BTF overlapped with the addition
of support for it.

The rest were more simple overlapping changes, except the
renesas ravb binding update, which had to follow a file
move as well as a YAML conversion.

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-05 18:40:01 -07:00
Cong Wang
580e4273d7 net_sched: check error pointer in tcf_dump_walker()
Although we take RTNL on dump path, it is possible to
skip RTNL on insertion path. So the following race condition
is possible:

rtnl_lock()		// no rtnl lock
			mutex_lock(&idrinfo->lock);
			// insert ERR_PTR(-EBUSY)
			mutex_unlock(&idrinfo->lock);
tc_dump_action()
rtnl_unlock()

So we have to skip those temporary -EBUSY entries on dump path
too.

Reported-and-tested-by: syzbot+b47bc4f247856fb4d9e1@syzkaller.appspotmail.com
Fixes: 0fedc63fad ("net_sched: commit action insertions together")
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>
2020-10-04 14:53:06 -07:00
Cong Wang
1aad804990 net_sched: remove a redundant goto chain check
All TC actions call tcf_action_check_ctrlact() to validate
goto chain, so this check in tcf_action_init_1() is actually
redundant. Remove it to save troubles of leaking memory.

Fixes: e49d8c22f1 ("net_sched: defer tcf_idr_insert() in tcf_action_init_1()")
Reported-by: Vlad Buslov <vladbu@mellanox.com>
Suggested-by: Davide Caratti <dcaratti@redhat.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Reviewed-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-28 12:58:45 -07:00
Cong Wang
0fedc63fad net_sched: commit action insertions together
syzbot is able to trigger a failure case inside the loop in
tcf_action_init(), and when this happens we clean up with
tcf_action_destroy(). But, as these actions are already inserted
into the global IDR, other parallel process could free them
before tcf_action_destroy(), then we will trigger a use-after-free.

Fix this by deferring the insertions even later, after the loop,
and committing all the insertions in a separate loop, so we will
never fail in the middle of the insertions any more.

One side effect is that the window between alloction and final
insertion becomes larger, now it is more likely that the loop in
tcf_del_walker() sees the placeholder -EBUSY pointer. So we have
to check for error pointer in tcf_del_walker().

Reported-and-tested-by: syzbot+2287853d392e4b42374a@syzkaller.appspotmail.com
Fixes: 0190c1d452 ("net: sched: atomically check-allocate action")
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
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
Tom Rix
c1f1f16c4d net: sched: skip an unnecessay check
Reviewing the error handling in tcf_action_init_1()
most of the early handling uses

err_out:
	if (cookie) {
		kfree(cookie->data);
		kfree(cookie);
	}

before cookie could ever be set.

So skip the unnecessay check.

Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-08 19:34:36 -07:00