In commit ec3ed293 ("net_sched: change tcf_del_walker() to take idrinfo->lock")
we move fl_hw_destroy_tmplt() to a workqueue to avoid blocking
with the spinlock held. Unfortunately, this causes a lot of
troubles here:

1. tcf_chain_destroy() could be called right after we queue the work
   but before the work runs. This is a use-after-free.

2. The chain refcnt is already 0, we can't even just hold it again.
   We can check refcnt==1 but it is ugly.

3. The chain with refcnt 0 is still visible in its block, which means
   it could be still found and used!

4. The block has a refcnt too, we can't hold it without introducing a
   proper API either.

We can make it working but the end result is ugly. Instead of wasting
time on reviewing it, let's just convert the troubling spinlock to
a mutex, which allows us to use non-atomic allocations too.

Fixes: ec3ed293 ("net_sched: change tcf_del_walker() to take idrinfo->lock")
Reported-by: NIdo Schimmel <idosch@idosch.org>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Vlad Buslov <vladbu@mellanox.com>
Cc: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Tested-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add additional counters that will store the bytes/packets processed by
hardware. These will be exported through the netlink interface for
displaying by the iproute2 tc tool
Signed-off-by: NEelco Chaudron <echaudro@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Action API was changed to work with actions and action_idr in concurrency
safe manner, however tcf_del_walker() still uses actions without taking a
reference or idrinfo->lock first, and deletes them directly, disregarding
possible concurrent delete.

Change tcf_del_walker() to take idrinfo->lock while iterating over actions
and use new tcf_idr_release_unsafe() to release them while holding the
lock.

And the blocking function fl_hw_destroy_tmplt() could be called when we
put a filter chain, so defer it to a work queue.
Signed-off-by: NVlad Buslov <vladbu@mellanox.com>
[xiyou.wangcong@gmail.com: heavily modify the code and changelog]
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently, tcf_action_delete() nulls actions array pointer after putting
and deleting it. However, if tcf_idr_delete_index() returns an error,
pointer to action is not set to null. That results it being released second
time in error handling code of tca_action_gd().

Kasan error:

[  807.367755] ==================================================================
[  807.375844] BUG: KASAN: use-after-free in tc_setup_cb_call+0x14e/0x250
[  807.382763] Read of size 8 at addr ffff88033e636000 by task tc/2732

[  807.391289] CPU: 0 PID: 2732 Comm: tc Tainted: G        W         4.19.0-rc1+ #799
[  807.399542] Hardware name: Supermicro SYS-2028TP-DECR/X10DRT-P, BIOS 2.0b 03/30/2017
[  807.407948] Call Trace:
[  807.410763]  dump_stack+0x92/0xeb
[  807.414456]  print_address_description+0x70/0x360
[  807.419549]  kasan_report+0x14d/0x300
[  807.423582]  ? tc_setup_cb_call+0x14e/0x250
[  807.428150]  tc_setup_cb_call+0x14e/0x250
[  807.432539]  ? nla_put+0x65/0xe0
[  807.436146]  fl_dump+0x394/0x3f0 [cls_flower]
[  807.440890]  ? fl_tmplt_dump+0x140/0x140 [cls_flower]
[  807.446327]  ? lock_downgrade+0x320/0x320
[  807.450702]  ? lock_acquire+0xe2/0x220
[  807.454819]  ? is_bpf_text_address+0x5/0x140
[  807.459475]  ? memcpy+0x34/0x50
[  807.462980]  ? nla_put+0x65/0xe0
[  807.466582]  tcf_fill_node+0x341/0x430
[  807.470717]  ? tcf_block_put+0xe0/0xe0
[  807.474859]  tcf_node_dump+0xdb/0xf0
[  807.478821]  fl_walk+0x8e/0x170 [cls_flower]
[  807.483474]  tcf_chain_dump+0x35a/0x4d0
[  807.487703]  ? tfilter_notify+0x170/0x170
[  807.492091]  ? tcf_fill_node+0x430/0x430
[  807.496411]  tc_dump_tfilter+0x362/0x3f0
[  807.500712]  ? tc_del_tfilter+0x850/0x850
[  807.505104]  ? kasan_unpoison_shadow+0x30/0x40
[  807.509940]  ? __mutex_unlock_slowpath+0xcf/0x410
[  807.515031]  netlink_dump+0x263/0x4f0
[  807.519077]  __netlink_dump_start+0x2a0/0x300
[  807.523817]  ? tc_del_tfilter+0x850/0x850
[  807.528198]  rtnetlink_rcv_msg+0x46a/0x6d0
[  807.532671]  ? rtnl_fdb_del+0x3f0/0x3f0
[  807.536878]  ? tc_del_tfilter+0x850/0x850
[  807.541280]  netlink_rcv_skb+0x18d/0x200
[  807.545570]  ? rtnl_fdb_del+0x3f0/0x3f0
[  807.549773]  ? netlink_ack+0x500/0x500
[  807.553913]  netlink_unicast+0x2d0/0x370
[  807.558212]  ? netlink_attachskb+0x340/0x340
[  807.562855]  ? _copy_from_iter_full+0xe9/0x3e0
[  807.567677]  ? import_iovec+0x11e/0x1c0
[  807.571890]  netlink_sendmsg+0x3b9/0x6a0
[  807.576192]  ? netlink_unicast+0x370/0x370
[  807.580684]  ? netlink_unicast+0x370/0x370
[  807.585154]  sock_sendmsg+0x6b/0x80
[  807.589015]  ___sys_sendmsg+0x4a1/0x520
[  807.593230]  ? copy_msghdr_from_user+0x210/0x210
[  807.598232]  ? do_wp_page+0x174/0x880
[  807.602276]  ? __handle_mm_fault+0x749/0x1c10
[  807.607021]  ? __handle_mm_fault+0x1046/0x1c10
[  807.611849]  ? __pmd_alloc+0x320/0x320
[  807.615973]  ? check_chain_key+0x140/0x1f0
[  807.620450]  ? check_chain_key+0x140/0x1f0
[  807.624929]  ? __fget_light+0xbc/0xd0
[  807.628970]  ? __sys_sendmsg+0xd7/0x150
[  807.633172]  __sys_sendmsg+0xd7/0x150
[  807.637201]  ? __ia32_sys_shutdown+0x30/0x30
[  807.641846]  ? up_read+0x53/0x90
[  807.645442]  ? __do_page_fault+0x484/0x780
[  807.649949]  ? do_syscall_64+0x1e/0x2c0
[  807.654164]  do_syscall_64+0x72/0x2c0
[  807.658198]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
[  807.663625] RIP: 0033:0x7f42e9870150
[  807.667568] Code: 8b 15 3c 7d 2b 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb cd 66 0f 1f 44 00 00 83 3d b9 d5 2b 00 00 75 10 b8 2e 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 be cd 00 00 48 89 04 24
[  807.687328] RSP: 002b:00007ffdbf595b58 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[  807.695564] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f42e9870150
[  807.703083] RDX: 0000000000000000 RSI: 00007ffdbf595b80 RDI: 0000000000000003
[  807.710605] RBP: 00007ffdbf599d90 R08: 0000000000679bc0 R09: 000000000000000f
[  807.718127] R10: 00000000000005e7 R11: 0000000000000246 R12: 00007ffdbf599d88
[  807.725651] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

[  807.735048] Allocated by task 2687:
[  807.738902]  kasan_kmalloc+0xa0/0xd0
[  807.742852]  __kmalloc+0x118/0x2d0
[  807.746615]  tcf_idr_create+0x44/0x320
[  807.750738]  tcf_nat_init+0x41e/0x530 [act_nat]
[  807.755638]  tcf_action_init_1+0x4e0/0x650
[  807.760104]  tcf_action_init+0x1ce/0x2d0
[  807.764395]  tcf_exts_validate+0x1d8/0x200
[  807.768861]  fl_change+0x55a/0x26b4 [cls_flower]
[  807.773845]  tc_new_tfilter+0x748/0xa20
[  807.778051]  rtnetlink_rcv_msg+0x56a/0x6d0
[  807.782517]  netlink_rcv_skb+0x18d/0x200
[  807.786804]  netlink_unicast+0x2d0/0x370
[  807.791095]  netlink_sendmsg+0x3b9/0x6a0
[  807.795387]  sock_sendmsg+0x6b/0x80
[  807.799240]  ___sys_sendmsg+0x4a1/0x520
[  807.803445]  __sys_sendmsg+0xd7/0x150
[  807.807473]  do_syscall_64+0x72/0x2c0
[  807.811506]  entry_SYSCALL_64_after_hwframe+0x49/0xbe

[  807.818776] Freed by task 2728:
[  807.822283]  __kasan_slab_free+0x122/0x180
[  807.826752]  kfree+0xf4/0x2f0
[  807.830080]  __tcf_action_put+0x5a/0xb0
[  807.834281]  tcf_action_put_many+0x46/0x70
[  807.838747]  tca_action_gd+0x232/0xc40
[  807.842862]  tc_ctl_action+0x215/0x230
[  807.846977]  rtnetlink_rcv_msg+0x56a/0x6d0
[  807.851444]  netlink_rcv_skb+0x18d/0x200
[  807.855731]  netlink_unicast+0x2d0/0x370
[  807.860021]  netlink_sendmsg+0x3b9/0x6a0
[  807.864312]  sock_sendmsg+0x6b/0x80
[  807.868166]  ___sys_sendmsg+0x4a1/0x520
[  807.872372]  __sys_sendmsg+0xd7/0x150
[  807.876401]  do_syscall_64+0x72/0x2c0
[  807.880431]  entry_SYSCALL_64_after_hwframe+0x49/0xbe

[  807.887704] The buggy address belongs to the object at ffff88033e636000
                which belongs to the cache kmalloc-256 of size 256
[  807.900909] The buggy address is located 0 bytes inside of
                256-byte region [ffff88033e636000, ffff88033e636100)
[  807.913155] The buggy address belongs to the page:
[  807.918322] page:ffffea000cf98d80 count:1 mapcount:0 mapping:ffff88036f80ee00 index:0x0 compound_mapcount: 0
[  807.928831] flags: 0x5fff8000008100(slab|head)
[  807.933647] raw: 005fff8000008100 ffffea000db44f00 0000000400000004 ffff88036f80ee00
[  807.942050] raw: 0000000000000000 0000000080190019 00000001ffffffff 0000000000000000
[  807.950456] page dumped because: kasan: bad access detected

[  807.958240] Memory state around the buggy address:
[  807.963405]  ffff88033e635f00: fc fc fc fc fb fb fb fb fb fb fb fc fc fc fc fb
[  807.971288]  ffff88033e635f80: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc
[  807.979166] >ffff88033e636000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  807.994882]                    ^
[  807.998477]  ffff88033e636080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  808.006352]  ffff88033e636100: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
[  808.014230] ==================================================================
[  808.022108] Disabling lock debugging due to kernel taint

Fixes: edfaf94f ("net_sched: improve and refactor tcf_action_put_many()")
Signed-off-by: NVlad Buslov <vladbu@mellanox.com>
Acked-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This reverts commit 331a9295 ("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: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

After the commit 802bfb19 ("net/sched: user-space can't set
unknown tcfa_action values"), unknown tcfa_action values are
converted to TC_ACT_UNSPEC, but the common agreement is instead
rejecting such configurations.

This change also introduces a helper to simplify the destruction
of a single action, avoiding code duplication.

v1 -> v2:
 - helper is now static and renamed according to act_* convention
 - updated extack message, according to the new behavior

Fixes: 802bfb19 ("net/sched: user-space can't set unknown tcfa_action values")
Signed-off-by: NPaolo Abeni <pabeni@redhat.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

After commit 90b73b77, list_head is no longer needed.
Now we just need to convert the list iteration to array
iteration for drivers.

Fixes: 90b73b77 ("net: sched: change action API to use array of pointers to actions")
Cc: Jiri Pirko <jiri@mellanox.com>
Cc: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

tcf_idr_check() is replaced by tcf_idr_check_alloc(),
and __tcf_idr_check() now can be folded into tcf_idr_search().

Fixes: 0190c1d4 ("net: sched: atomically check-allocate action")
Cc: Jiri Pirko <jiri@mellanox.com>
Cc: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fixes: 16af6067 ("net: sched: implement reference counted action release")
Cc: Jiri Pirko <jiri@mellanox.com>
Cc: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: b409074e ("net: sched: add 'delete' function to action ops")
Cc: Jiri Pirko <jiri@mellanox.com>
Cc: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

tcf_action_put_many() is mostly called to clean up actions on
failure path, but tcf_action_put_many(&actions[acts_deleted]) is
used in the ugliest way: it passes a slice of the array and
uses an additional NULL at the end to avoid out-of-bound
access.

acts_deleted is completely unnecessary since we can teach
tcf_action_put_many() scan the whole array and checks against
NULL pointer. Which also means tcf_action_delete() should
set deleted action pointers to NULL to avoid double free.

Fixes: 90b73b77 ("net: sched: change action API to use array of pointers to actions")
Cc: Jiri Pirko <jiri@mellanox.com>
Cc: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently, when initializing an action, the user-space can specify
and use arbitrary values for the tcfa_action field. If the value
is unknown by the kernel, is implicitly threaded as TC_ACT_UNSPEC.

This change explicitly checks for unknown values at action creation
time, and explicitly convert them to TC_ACT_UNSPEC. No functional
changes are introduced, but this will allow introducing tcfa_action
values not exposed to user-space in a later patch.

Note: we can't use the above to hide TC_ACT_REDIRECT from user-space,
as the latter is already part of uAPI.

v3 -> v4:
 - use an helper to check for action validity (JiriP)
 - emit an extack for invalid actions (JiriP)
v4 -> v5:
 - keep messages on a single line, drop net_warn (Marcelo)
Signed-off-by: NPaolo Abeni <pabeni@redhat.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In case a chain is empty and not explicitly created by a user,
such chain should not exist. The only exception is if there is
an action "goto chain" pointing to it. In that case, don't show the
chain in the dump. Track the chain references held by actions and
use them to find out if a chain should or should not be shown
in chain dump.
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix action attribute size calculation function to take rcu read lock and
access act_cookie pointer with rcu dereference.

Fixes: eec94fdb ("net: sched: use rcu for action cookie update")
Reported-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: NVlad Buslov <vladbu@mellanox.com>
Reviewed-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The kbuild test robot reports:

>> net/sched/act_api.c:71:15: sparse: incorrect type in initializer (different address spaces) @@    expected struct tc_cookie [noderef] <asn:4>*__ret @@    got [noderef] <asn:4>*__ret @@
   net/sched/act_api.c:71:15:    expected struct tc_cookie [noderef] <asn:4>*__ret
   net/sched/act_api.c:71:15:    got struct tc_cookie *new_cookie
>> net/sched/act_api.c:71:13: sparse: incorrect type in assignment (different address spaces) @@    expected struct tc_cookie *old @@    got struct tc_cookie [noderef] <struct tc_cookie *old @@
   net/sched/act_api.c:71:13:    expected struct tc_cookie *old
   net/sched/act_api.c:71:13:    got struct tc_cookie [noderef] <asn:4>*[assigned] __ret
>> net/sched/act_api.c:132:48: sparse: dereference of noderef expression

Handle this in the usual way by force casting away the __rcu annotation
when we are using xchg() on it.

Fixes: eec94fdb ("net: sched: use rcu for action cookie update")
Reported-by: Nkbuild test robot <lkp@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Act API used linked list to pass set of actions to functions. It is
intrusive data structure that stores list nodes inside action structure
itself, which means it is not safe to modify such list concurrently.
However, action API doesn't use any linked list specific operations on this
set of actions, so it can be safely refactored into plain pointer array.

Refactor action API to use array of pointers to tc_actions instead of
linked list. Change argument 'actions' type of exported action init,
destroy and dump functions.
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NVlad Buslov <vladbu@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: NVlad Buslov <vladbu@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Change action API to assume that action init function always takes
reference to action, even when overwriting existing action. This is
necessary because action API continues to use action pointer after init
function is done. At this point action becomes accessible for concurrent
modifications, so user must always hold reference to it.

Implement helper put list function to atomically release list of actions
after action API init code is done using them.
Reviewed-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: NVlad Buslov <vladbu@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: NVlad Buslov <vladbu@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Implement helper delete function that uses new action ops 'delete', instead
of destroying action directly. This is required so act API could delete
actions by index, without holding any references to action that is being
deleted.

Implement function __tcf_action_put() that releases reference to action and
frees it, if necessary. Refactor action deletion code to use new put
function and not to rely on rtnl lock. Remove rtnl lock assertions that are
no longer needed.
Reviewed-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: NVlad Buslov <vladbu@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Implement new action API function that atomically finds and deletes action
from idr by index. Intended to be used by lockless actions that do not rely
on rtnl lock.
Reviewed-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: NVlad Buslov <vladbu@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Without rtnl lock protection it is no longer safe to use pointer to tc
action without holding reference to it. (it can be destroyed concurrently)

Remove unsafe action idr lookup function. Instead of it, implement safe tcf
idr check function that atomically looks up action in idr and increments
its reference and bind counters. Implement both action search and check
using new safe function

Reference taken by idr check is temporal and should not be accounted by
userspace clients (both logically and to preserver current API behavior).
Subtract temporal reference when dumping action to userspace using existing
tca_get_fill function arguments.
Reviewed-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: NVlad Buslov <vladbu@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: NVlad Buslov <vladbu@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: NVlad Buslov <vladbu@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Implement functions to atomically update and free action cookie
using rcu mechanism.
Reviewed-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: NVlad Buslov <vladbu@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Initial net_device implementation used ingress_lock spinlock to synchronize
ingress path of device. This lock was used in both process and bh context.
In some code paths action map lock was obtained while holding ingress_lock.
Commit e1e992e5 ("[NET_SCHED] protect action config/dump from irqs")
modified actions to always disable bh, while using action map lock, in
order to prevent deadlock on ingress_lock in softirq. This lock was removed
from net_device, so disabling bh, while accessing action map, is no longer
necessary.

Replace all action idr spinlock usage with regular calls that do not
disable bh.
Signed-off-by: NVlad Buslov <vladbu@mellanox.com>
Acked-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Synchronous pernet_operations are not allowed anymore.
All are asynchronous. So, drop the structure member.
Signed-off-by: NKirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fixes a bug in the tcf_dump_walker function that can cause some actions
to not be reported when dumping a large number of actions. This issue
became more aggrevated when cookies feature was added. In particular
this issue is manifest when large cookie values are assigned to the
actions and when enough actions are created that the resulting table
must be dumped in multiple batches.

The number of actions returned in each batch is limited by the total
number of actions and the memory buffer size.  With small cookies
the numeric limit is reached before the buffer size limit, which avoids
the code path triggering this bug. When large cookies are used buffer
fills before the numeric limit, and the erroneous code path is hit.

For example after creating 32 csum actions with the cookie
aaaabbbbccccdddd

$ tc actions ls action csum
total acts 26

    action order 0: csum (tcp) action continue
    index 1 ref 1 bind 0
    cookie aaaabbbbccccdddd

    .....

    action order 25: csum (tcp) action continue
    index 26 ref 1 bind 0
    cookie aaaabbbbccccdddd
total acts 6

    action order 0: csum (tcp) action continue
    index 28 ref 1 bind 0
    cookie aaaabbbbccccdddd

    ......

    action order 5: csum (tcp) action continue
    index 32 ref 1 bind 0
    cookie aaaabbbbccccdddd

Note that the action with index 27 is omitted from the report.

Fixes: 4b3550ef ("[NET_SCHED]: Use nla_nest_start/nla_nest_end")"
Signed-off-by: NCraig Dillabaugh <cdillaba@mojatatu.com>
Acked-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

tcf_idr_cleanup() is no more used, so remove it.
Suggested-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavide Caratti <dcaratti@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Introduce routines to calculate size of the shared tc netlink attributes
and the full message size including netlink header and tc service header.

Update add/delete action logic to have the size for event messages,
the size is passed to tcf_add_notify() and tcf_del_notify() where the
notification message is being allocated and constructed.
Signed-off-by: NRoman Mashak <mrv@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Introduce a new function argument to carry total attributes size for
correct allocation of skb in event messages.
Signed-off-by: NRoman Mashak <mrv@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NRoman Mashak <mrv@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NAlexander Aring <aring@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NAlexander Aring <aring@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NAlexander Aring <aring@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NAlexander Aring <aring@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds extack support for generic act handling. The extack
will be set deeper to each called function which is not part of netdev
core api.

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

Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: NAlexander Aring <aring@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds extack to tcf_action_init and tcf_action_init_1
functions. These are necessary to make individual extack handling in
each act implementation.

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

Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: NAlexander Aring <aring@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch is used by subsequent patches. It fixes code style issues
caught by checkpatch.
Signed-off-by: NAlexander Aring <aring@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It was mis-applied and the changes had rejects.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>