Commit Graph

273 Commits

Author SHA1 Message Date
Jiri Pirko
b7b4247d55 net: sched: return -ENOENT when trying to remove filter from non-existent chain
When chain 0 was implicitly created, removal of non-existent filter from
chain 0 gave -ENOENT. Once chain 0 became non-implicit, the same call is
giving -EINVAL. Fix this by returning -ENOENT in that case.

Reported-by: Roman Mashak <mrv@mojatatu.com>
Fixes: f71e0ca4db ("net: sched: Avoid implicit chain 0 creation")
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-27 15:16:16 -07:00
Jiri Pirko
d5ed72a55b net: sched: fix extack error message when chain is failed to be created
Instead "Cannot find" say "Cannot create".

Fixes: c35a4acc29 ("net: sched: cls_api: handle generic cls errors")
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-27 15:16:16 -07:00
Vlad Buslov
84a75b329b net: sched: extend action ops with put_dev callback
As a preparation for removing dependency on rtnl lock from rules update
path, all users of shared objects must take reference while working with
them.

Extend action ops with put_dev() API to be used on net device returned by
get_dev().

Modify mirred action (only action that implements get_dev callback):
- Take reference to net device in get_dev.
- Implement put_dev API that releases reference to net device.

Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-11 12:37:10 -07:00
Jiri Pirko
63cc5bcc9f net: sched: fix block->refcnt decrement
Currently the refcnt is never decremented in case the value is not 1.
Fix it by adding decrement in case the refcnt is not 1.

Reported-by: Vlad Buslov <vladbu@mellanox.com>
Fixes: f71e0ca4db ("net: sched: Avoid implicit chain 0 creation")
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-09 14:12:04 -07:00
Jiri Pirko
5ca8a25c14 net: sched: fix flush on non-existing chain
User was able to perform filter flush on chain 0 even if it didn't have
any filters in it. With the patch that avoided implicit chain 0
creation, this changed. So in case user wants filter flush on chain
which does not exist, just return success. There's no reason for non-0
chains to behave differently than chain 0, so do the same for them.

Reported-by: Ido Schimmel <idosch@mellanox.com>
Fixes: f71e0ca4db ("net: sched: Avoid implicit chain 0 creation")
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-03 09:44:37 -07:00
Jiri Pirko
290b1c8b1a net: sched: make tcf_chain_{get,put}() static
These are no longer used outside of cls_api.c so make them static.
Move tcf_chain_flush() to avoid fwd declaration of tcf_chain_put().

Signed-off-by: Jiri Pirko <jiri@mellanox.com>

v1->v2:
- new patch

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-01 10:06:19 -07:00
Jiri Pirko
5368140730 net: sched: fix notifications for action-held chains
Chains that only have action references serve as placeholders.
Until a non-action reference is created, user should not be aware
of the chain. Also he should not receive any notifications about it.
So send notifications for the new chain only in case the chain gets
the first non-action reference. Symmetrically to that, when
the last non-action reference is dropped, send the notification about
deleted chain.

Reported-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>

v1->v2:
- made __tcf_chain_{get,put}() static as suggested by Cong

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-01 10:06:19 -07:00
Jiri Pirko
3d32f4c548 net: sched: change name of zombie chain to "held_by_acts_only"
As mentioned by Cong and Jakub during the review process, it is a bit
odd to sometimes (act flow) create a new chain which would be
immediately a "zombie". So just rename it to "held_by_acts_only".

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Suggested-by: Cong Wang <xiyou.wangcong@gmail.com>
Suggested-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-01 10:06:19 -07:00
Jiri Pirko
1f3ed383fb net: sched: don't dump chains only held by actions
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: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-27 09:38:46 -07:00
Jiri Pirko
c921d7db3d net: sched: unmark chain as explicitly created on delete
Once user manually deletes the chain using "chain del", the chain cannot
be marked as explicitly created anymore.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Fixes: 32a4f5ecd7 ("net: sched: introduce chain object to uapi")
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-26 14:12:58 -07:00
Gustavo A. R. Silva
2ed9db3074 net: sched: cls_api: fix dead code in switch
Code at line 1850 is unreachable. Fix this by removing the break
statement above it, so the code for case RTM_GETCHAIN can be
properly executed.

Addresses-Coverity-ID: 1472050 ("Structurally dead code")
Fixes: 32a4f5ecd7 ("net: sched: introduce chain object to uapi")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-26 14:09:27 -07:00
Jiri Pirko
9f407f1768 net: sched: introduce chain templates
Allow user to set a template for newly created chains. Template lock
down the chain for particular classifier type/options combinations.
The classifier needs to support templates, otherwise kernel would
reply with error.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-23 20:44:12 -07:00
Jiri Pirko
32a4f5ecd7 net: sched: introduce chain object to uapi
Allow user to create, destroy, get and dump chain objects. Do that by
extending rtnl commands by the chain-specific ones. User will now be
able to explicitly create or destroy chains (so far this was done only
automatically according the filter/act needs and refcounting). Also, the
user will receive notification about any chain creation or destuction.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-23 20:44:12 -07:00
Jiri Pirko
f71e0ca4db net: sched: Avoid implicit chain 0 creation
Currently, chain 0 is implicitly created during block creation. However
that does not align with chain object exposure, creation and destruction
api introduced later on. So make the chain 0 behave the same way as any
other chain and only create it when it is needed. Since chain 0 is
somehow special as the qdiscs need to hold pointer to the first chain
tp, this requires to move the chain head change callback infra to the
block structure.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-23 20:44:12 -07:00
Jiri Pirko
f34e8bff58 net: sched: push ops lookup bits into tcf_proto_lookup_ops()
Push all bits that take care of ops lookup, including module loading
outside tcf_proto_create() function, into tcf_proto_lookup_ops()

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-23 20:44:12 -07:00
Gustavo A. R. Silva
baa2d2b17e net: sched: use PTR_ERR_OR_ZERO macro in tcf_block_cb_register
This line makes up what macro PTR_ERR_OR_ZERO already does. So,
make use of PTR_ERR_OR_ZERO rather than an open-code version.

This code was detected with the help of Coccinelle.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-21 16:17:08 -07:00
David S. Miller
c4c5551df1 Merge ra.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux
All conflicts were trivial overlapping changes, so reasonably
easy to resolve.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-20 21:17:12 -07:00
YueHaibing
5318918390 net: sched: Using NULL instead of plain integer
Fixes the following sparse warnings:

net/sched/cls_api.c:1101:43: warning: Using plain integer as NULL pointer
net/sched/cls_api.c:1492:75: warning: Using plain integer as NULL pointer

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-18 13:44:07 -07:00
Vlad Buslov
01683a1469 net: sched: refactor flower walk to iterate over idr
Extend struct tcf_walker with additional 'cookie' field. It is intended to
be used by classifier walk implementations to continue iteration directly
from particular filter, instead of iterating 'skip' number of times.

Change flower walk implementation to save filter handle in 'cookie'. Each
time flower walk is called, it looks up filter with saved handle directly
with idr, instead of iterating over filter linked list 'skip' number of
times. This change improves complexity of dumping flower classifier from
quadratic to linearithmic. (assuming idr lookup has logarithmic complexity)

Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Reported-by: Simon Horman <simon.horman@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-13 18:24:27 -07:00
Vlad Buslov
90b73b77d0 net: sched: change action API to use array of pointers to actions
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: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-08 12:42:29 +09:00
Vlad Buslov
16af606739 net: sched: implement reference counted action release
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: 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
John Hurley
326367427c net: sched: call reoffload op on block callback reg
Call the reoffload tcf_proto_op on all tcf_proto nodes in all chains of a
block when a callback tries to register to a block that already has
offloaded rules. If all existing rules cannot be offloaded then the
registration is rejected. This replaces the previous policy of rejecting
such callback registration outright.

On unregistration of a callback, the rules are flushed for that given cb.
The implementation of block sharing in the NFP driver, for example,
duplicates shared rules to all devs bound to a block. This meant that
rules could still exist in hw even after a device is unbound from a block
(assuming the block still remains active).

Signed-off-by: John Hurley <john.hurley@netronome.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-26 23:21:33 +09:00
John Hurley
60513bd82c net: sched: pass extack pointer to block binds and cb registration
Pass the extact struct from a tc qdisc add to the block bind function and,
in turn, to the setup_tc ndo of binding device via the tc_block_offload
struct. Pass this back to any block callback registrations to allow
netlink logging of fails in the bind process.

Signed-off-by: John Hurley <john.hurley@netronome.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-26 23:21:32 +09:00
David S. Miller
9a99dc1c41 Revert "net: sched: cls: Fix offloading when ingress dev is vxlan"
This reverts commit d96a43c664.

This potentially breaks things, so reverting as per
request by Jakub Kicinski.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-06 13:55:47 -04:00
Paul Blakey
d96a43c664 net: sched: cls: Fix offloading when ingress dev is vxlan
When using a vxlan device as the ingress dev, we count it as a
"no offload dev", so when such a rule comes and err stop is true,
we fail early and don't try the egdev route which can offload it
through the egress device.

Fix that by not calling the block offload if one of the devices
attached to it is not offload capable, but make sure egress on such case
is capable instead.

Fixes: caa7260156 ("net: sched: keep track of offloaded filters [..]")
Reviewed-by: Roi Dayan <roid@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Paul Blakey <paulb@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-05 10:29:58 -04:00
Vlad Buslov
0e3990356d net: sched: return error code when tcf proto is not found
If requested tcf proto is not found, get and del filter netlink protocol
handlers output error message to extack, but do not return actual error
code. Add check to return ENOENT when result of tp find function is NULL
pointer.

Fixes: c431f89b18 ("net: sched: split tc_ctl_tfilter into three handlers")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-04 17:31:44 -04:00
Vlad Buslov
c431f89b18 net: sched: split tc_ctl_tfilter into three handlers
tc_ctl_tfilter handles three netlink message types: RTM_NEWTFILTER,
RTM_DELTFILTER, RTM_GETTFILTER. However, implementation of this function
involves a lot of branching on specific message type because most of the
code is message-specific. This significantly complicates adding new
functionality and doesn't provide much benefit of code reuse.

Split tc_ctl_tfilter to three standalone functions that handle filter new,
delete and get requests.

The only truly protocol independent part of tc_ctl_tfilter is code that
looks up queue, class, and block. Refactor this code to standalone
tcf_block_find function that is used by all three new handlers.

Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-01 11:13:50 -04:00
David S. Miller
5b79c2af66 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Lots of easy overlapping changes in the confict
resolutions here.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-26 19:46:15 -04:00
Cong Wang
aaa908ffbe net_sched: switch to rcu_work
Commit 05f0fe6b74 ("RCU, workqueue: Implement rcu_work") introduces
new API's for dispatching work in a RCU callback. Now we can just
switch to the new API's for tc filters. This could get rid of a lot
of code.

Cc: Tejun Heo <tj@kernel.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.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>
2018-05-24 22:56:15 -04:00
Or Gerlitz
f8f4bef322 net : sched: cls_api: deal with egdev path only if needed
When dealing with ingress rule on a netdev, if we did fine through the
conventional path, there's no need to continue into the egdev route,
and we can stop right there.

Not doing so may cause a 2nd rule to be added by the cls api layer
with the ingress being the egdev.

For example, under sriov switchdev scheme, a user rule of VFR A --> VFR B
will end up with two HW rules (1) VF A --> VF B and (2) uplink --> VF B

Fixes: 208c0f4b52 ('net: sched: use tc_setup_cb_call to call per-block callbacks')
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-24 22:12:22 -04:00
Jiri Pirko
d68d75fdc3 net: sched: fix error path in tcf_proto_create() when modules are not configured
In case modules are not configured, error out when tp->ops is null
and prevent later null pointer dereference.

Fixes: 33a48927c1 ("sched: push TC filter protocol creation into a separate function")
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-11 16:34:38 -04:00
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
Roman Mashak
d04e6990c9 net sched actions: update Add/Delete action API with new argument
Introduce a new function argument to carry total attributes size for
correct allocation of skb in event messages.

Signed-off-by: Roman Mashak <mrv@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-09 11:25:11 -05:00
Kirill Tkhai
02df428ca2 net: Convert simple pernet_operations
These pernet_operations make pretty simple actions
like variable initialization on init, debug checks
on exit, and so on, and they obviously are able
to be executed in parallel with any others:

vrf_net_ops
lockd_net_ops
grace_net_ops
xfrm6_tunnel_net_ops
kcm_net_ops
tcf_net_ops

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-27 11:01:35 -05:00
David S. Miller
f74290fdb3 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-02-24 00:04:20 -05:00
Roman Kapl
5ae437ad5a net: sched: report if filter is too large to dump
So far, if the filter was too large to fit in the allocated skb, the
kernel did not return any error and stopped dumping. Modify the dumper
so that it returns -EMSGSIZE when a filter fails to dump and it is the
first filter in the skb. If we are not first, we will get a next chance
with more room.

I understand this is pretty near to being an API change, but the
original design (silent truncation) can be considered a bug.

Note: The error case can happen pretty easily if you create a filter
with 32 actions and have 4kb pages. Also recent versions of iproute try
to be clever with their buffer allocation size, which in turn leads to

Signed-off-by: Roman Kapl <code@rkapl.cz>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-20 21:57:17 -05:00
David S. Miller
f5c0c6f429 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-02-19 18:46:11 -05:00
Alexander Aring
aea0d72789 net: sched: act: add extack to init
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: Alexander Aring <aring@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-16 16:04:53 -05:00
David S. Miller
ee99b2d8bf net: Revert sched action extack support series.
It was mis-applied and the changes had rejects.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-16 16:03:39 -05:00
Alexander Aring
10defbd29e net: sched: act: add extack to init
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: Alexander Aring <aring@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-16 15:44:42 -05:00
Jiri Pirko
bb047ddd14 net: sched: don't set q pointer for shared blocks
It is pointless to set block->q for block which are shared among
multiple qdiscs. So remove the assignment in that case. Do a bit of code
reshuffle to make block->index initialized at that point so we can use
tcf_block_shared() helper.

Reported-by: Cong Wang <xiyou.wangcong@gmail.com>
Fixes: 4861738775 ("net: sched: introduce shared filter blocks infrastructure")
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-13 12:29:02 -05:00
Matthew Wilcox
9ce75499ac cls_api: Convert to idr_alloc_u32
Use the new helper.

Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
2018-02-06 16:40:33 -05:00
Matthew Wilcox
322d884ba7 idr: Delete idr_find_ext function
Simply changing idr_remove's 'id' argument to 'unsigned long' works
for all callers.

Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
2018-02-06 16:40:32 -05:00
Matthew Wilcox
9c16094140 idr: Delete idr_remove_ext function
Simply changing idr_remove's 'id' argument to 'unsigned long' suffices
for all callers.

Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
2018-02-06 16:40:31 -05:00
Jakub Kicinski
715df5ecab net: sched: propagate extack to cls->destroy callbacks
Propagate extack to cls->destroy callbacks when called from
non-error paths.  On error paths pass NULL to avoid overwriting
the failure message.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-24 16:01:09 -05:00
Alexander Aring
571acf2106 net: sched: cls: add extack support for delete callback
This patch adds extack support for classifier delete callback api. This
prepares to handle extack support inside each specific classifier
implementation.

Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-19 15:52:51 -05:00
Alexander Aring
50a561900e net: sched: cls: add extack support for tcf_exts_validate
The tcf_exts_validate function calls the act api change callback. For
preparing extack support for act api, this patch adds the extack as
parameter for this function which is common used in cls implementations.

Furthermore the tcf_exts_validate will call action init callback which
prepares the TC action subsystem for extack support.

Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-19 15:52:51 -05:00
Alexander Aring
7306db38a6 net: sched: cls: add extack support for change callback
This patch adds extack support for classifier change callback api. This
prepares to handle extack support inside each specific classifier
implementation.

Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-19 15:52:51 -05:00
Alexander Aring
c35a4acc29 net: sched: cls_api: handle generic cls errors
This patch adds extack support for generic cls handling. The extack
will be set deeper to each called function which is not part of netdev
core api.

Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-19 15:52:51 -05:00
Jiri Pirko
d680b3524c net: sched: silence uninitialized parent variable warning in tc_dump_tfilter
When tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK, parent is still passed
down but the value is never used. Compiler does not recognize it and
issues a warning. Silence it down initializing parent to 0.

Fixes: 7960d1daf2 ("net: sched: use block index as a handle instead of qdisc when block is shared")
Reported-by: David Miller <davem@davemloft.net>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-18 10:37:12 -05:00
Jiri Pirko
7960d1daf2 net: sched: use block index as a handle instead of qdisc when block is shared
As the tcm_ifindex with value TCM_IFINDEX_MAGIC_BLOCK is invalid ifindex,
use it to indicate that we work with block, instead of qdisc.
So if tcm_ifindex is set to TCM_IFINDEX_MAGIC_BLOCK, tcm_parent is used
to carry block_index.

If the block is set to be shared between at least 2 qdiscs, it is
forbidden to use the qdisc handle to add/delete filters. In that case,
userspace has to pass block_index.

Also, for dump of the filters, in case the block is shared in between at
least 2 qdiscs, the each filter is dumped with tcm_ifindex value
TCM_IFINDEX_MAGIC_BLOCK and tcm_parent set to block_index. That gives
the user clear indication, that the filter belongs to a shared block
and not only to one qdisc under which it is dumped.

Suggested-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-17 14:53:57 -05:00
Jiri Pirko
caa7260156 net: sched: keep track of offloaded filters and check tc offload feature
During block bind, we need to check tc offload feature. If it is
disabled yet still the block contains offloaded filters, forbid the
bind. Also forbid to register callback for a block that already
contains offloaded filters, as the play back is not supported now.
For keeping track of offloaded filters there is a new counter
introduced, alongside with couple of helpers called from cls_* code.
These helpers set and clear TCA_CLS_FLAGS_IN_HW flag.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-17 14:53:57 -05:00
Jiri Pirko
edf6711c98 net: sched: remove classid and q fields from tcf_proto
Both are no longer used, so remove them.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-17 14:53:56 -05:00
Jiri Pirko
f36fe1c498 net: sched: introduce block mechanism to handle netif_keep_dst calls
Couple of classifiers call netif_keep_dst directly on q->dev. That is
not possible to do directly for shared blocke where multiple qdiscs are
owning the block. So introduce a infrastructure to keep track of the
block owners in list and use this list to implement block variant of
netif_keep_dst.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-17 14:53:56 -05:00
Jiri Pirko
9d3aaff3d8 net: sched: avoid usage of tp->q in tcf_classify
Use block index in the messages instead.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-17 14:53:56 -05:00
Jiri Pirko
4861738775 net: sched: introduce shared filter blocks infrastructure
Allow qdiscs to share filter blocks among them. Each qdisc type has to
use block get/put extended modifications that enable sharing.
Shared blocks are tracked within each net namespace and identified
by u32 index. This index is passed from user during the qdisc creation.
If user passes index that is not used by any other qdisc, new block
is created. If user passes index that is already used, the existing
block will be re-used.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-17 14:53:56 -05:00
Jiri Pirko
a9b19443ed net: sched: introduce support for multiple filter chain pointers registration
So far, there was possible only to register a single filter chain
pointer to block->chain[0]. However, when the blocks will get shareable,
we need to allow multiple filter chain pointers registration.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-17 14:53:56 -05:00
David S. Miller
6bb8824732 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
net/ipv6/ip6_gre.c is a case of parallel adds.

include/trace/events/tcp.h is a little bit more tricky.  The removal
of in-trace-macro ifdefs in 'net' paralleled with moving
show_tcp_state_name and friends over to include/trace/events/sock.h
in 'net-next'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-29 15:42:26 -05:00
Jiri Pirko
4853f128c1 net: sched: fix possible null pointer deref in tcf_block_put
We need to check block for being null in both tcf_block_put and
tcf_block_put_ext.

Fixes: 343723dd51 ("net: sched: fix clsact init error path")
Reported-by: Prashant Bhole <bhole_prashant_q7@lab.ntt.co.jp>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-26 13:02:05 -05:00
Alexander Aring
8d1a77f974 net: sch: api: add extack support in tcf_block_get
This patch adds extack support for the function tcf_block_get which is
a common used function in the tc subsystem. Callers which are interested
in the receiving error can assign extack to get a more detailed
information why tcf_block_get failed.

Cc: David Ahern <dsahern@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-21 12:32:51 -05:00
Alexander Aring
cbaacc4e8a net: sched: sch: add extack for block callback
This patch adds extack support for block callback to prepare per-qdisc
specific changes for extack.

Cc: David Ahern <dsahern@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-21 12:32:50 -05:00
David S. Miller
c30abd5e40 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Three sets of overlapping changes, two in the packet scheduler
and one in the meson-gxl PHY driver.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-16 22:11:55 -05:00
Jiri Pirko
343723dd51 net: sched: fix clsact init error path
Since in qdisc_create, the destroy op is called when init fails, we
don't do cleanup in init and leave it up to destroy.
This fixes use-after-free when trying to put already freed block.

Fixes: 6e40cf2d4d ("net: sched: use extended variants of block_get/put in ingress and clsact qdiscs")
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-15 15:43:12 -05:00
Pravin Shedge
83593010d3 net: remove duplicate includes
These duplicate includes have been found with scripts/checkincludes.pl but
they have been removed manually to avoid removing false positives.

Signed-off-by: Pravin Shedge <pravin.shedge4linux@gmail.com>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-13 13:18:46 -05:00
Jiri Pirko
df45bf84e4 net: sched: fix use-after-free in tcf_block_put_ext
Since the block is freed with last chain being put, once we reach the
end of iteration of list_for_each_entry_safe, the block may be
already freed. I'm hitting this only by creating and deleting clsact:

[  202.171952] ==================================================================
[  202.180182] BUG: KASAN: use-after-free in tcf_block_put_ext+0x240/0x390
[  202.187590] Read of size 8 at addr ffff880225539a80 by task tc/796
[  202.194508]
[  202.196185] CPU: 0 PID: 796 Comm: tc Not tainted 4.15.0-rc2jiri+ #5
[  202.203200] Hardware name: Mellanox Technologies Ltd. "MSN2100-CB2F"/"SA001017", BIOS 5.6.5 06/07/2016
[  202.213613] Call Trace:
[  202.216369]  dump_stack+0xda/0x169
[  202.220192]  ? dma_virt_map_sg+0x147/0x147
[  202.224790]  ? show_regs_print_info+0x54/0x54
[  202.229691]  ? tcf_chain_destroy+0x1dc/0x250
[  202.234494]  print_address_description+0x83/0x3d0
[  202.239781]  ? tcf_block_put_ext+0x240/0x390
[  202.244575]  kasan_report+0x1ba/0x460
[  202.248707]  ? tcf_block_put_ext+0x240/0x390
[  202.253518]  tcf_block_put_ext+0x240/0x390
[  202.258117]  ? tcf_chain_flush+0x290/0x290
[  202.262708]  ? qdisc_hash_del+0x82/0x1a0
[  202.267111]  ? qdisc_hash_add+0x50/0x50
[  202.271411]  ? __lock_is_held+0x5f/0x1a0
[  202.275843]  clsact_destroy+0x3d/0x80 [sch_ingress]
[  202.281323]  qdisc_destroy+0xcb/0x240
[  202.285445]  qdisc_graft+0x216/0x7b0
[  202.289497]  tc_get_qdisc+0x260/0x560

Fix this by holding the block also by chain 0 and put chain 0
explicitly, out of the list_for_each_entry_safe loop at the very
end of tcf_block_put_ext.

Fixes: efbf789739 ("net_sched: get rid of rcu_barrier() in tcf_block_put_ext()")
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-08 14:09:08 -05:00
Cong Wang
efbf789739 net_sched: get rid of rcu_barrier() in tcf_block_put_ext()
Both Eric and Paolo noticed the rcu_barrier() we use in
tcf_block_put_ext() could be a performance bottleneck when
we have a lot of tc classes.

Paolo provided the following to demonstrate the issue:

tc qdisc add dev lo root htb
for I in `seq 1 1000`; do
        tc class add dev lo parent 1: classid 1:$I htb rate 100kbit
        tc qdisc add dev lo parent 1:$I handle $((I + 1)): htb
        for J in `seq 1 10`; do
                tc filter add dev lo parent $((I + 1)): u32 match ip src 1.1.1.$J
        done
done
time tc qdisc del dev root

real    0m54.764s
user    0m0.023s
sys     0m0.000s

The rcu_barrier() there is to ensure we free the block after all chains
are gone, that is, to queue tcf_block_put_final() at the tail of workqueue.
We can achieve this ordering requirement by refcnt'ing tcf block instead,
that is, the tcf block is freed only when the last chain in this block is
gone. This also simplifies the code.

Paolo reported after this patch we get:

real    0m0.017s
user    0m0.000s
sys     0m0.017s

Tested-by: Paolo Abeni <pabeni@redhat.com>
Cc: Eric Dumazet <edumazet@google.com>
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 14:53:17 -05:00
Roman Kapl
a60b3f515d net: sched: crash on blocks with goto chain action
tcf_block_put_ext has assumed that all filters (and thus their goto
actions) are destroyed in RCU callback and thus can not race with our
list iteration. However, that is not true during netns cleanup (see
tcf_exts_get_net comment).

Prevent the user after free by holding all chains (except 0, that one is
already held). foreach_safe is not enough in this case.

To reproduce, run the following in a netns and then delete the ns:
    ip link add dtest type dummy
    tc qdisc add dev dtest ingress
    tc filter add dev dtest chain 1 parent ffff: handle 1 prio 1 flower action goto chain 2

Fixes: 822e86d997 ("net_sched: remove tcf_block_put_deferred()")
Signed-off-by: Roman Kapl <code@rkapl.cz>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-25 23:57:20 +09:00
Roman Kapl
d7aa04a5e8 net: sched: fix crash when deleting secondary chains
If you flush (delete) a filter chain other than chain 0 (such as when
deleting the device), the kernel may run into a use-after-free. The
chain refcount must not be decremented unless we are sure we are done
with the chain.

To reproduce the bug, run:
    ip link add dtest type dummy
    tc qdisc add dev dtest ingress
    tc filter add dev dtest chain 1  parent ffff: flower
    ip link del dtest

Introduced in: commit f93e1cdcf4 ("net/sched: fix filter flushing"),
but unless you have KAsan or luck, you won't notice it until
commit 0dadc117ac ("cls_flower: use tcf_exts_get_net() before call_rcu()")

Fixes: f93e1cdcf4 ("net/sched: fix filter flushing")
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Roman Kapl <code@rkapl.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-24 01:25:37 +09:00
David S. Miller
4dc6758d78 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Simple cases of overlapping changes in the packet scheduler.

Must easier to resolve this time.

Which probably means that I screwed it up somehow.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-10 10:00:18 +09:00
Cong Wang
e4b95c41df net_sched: introduce tcf_exts_get_net() and tcf_exts_put_net()
Instead of holding netns refcnt in tc actions, we can minimize
the holding time by saving it in struct tcf_exts instead. This
means we can just hold netns refcnt right before call_rcu() and
release it after tcf_exts_destroy() is done.

However, because on netns cleanup path we call tcf_proto_destroy()
too, obviously we can not hold netns for a zero refcnt, in this
case we have to do cleanup synchronously. It is fine for RCU too,
the caller cleanup_net() already waits for a grace period.

For other cases, refcnt is non-zero and we can safely grab it as
normal and release it after we are done.

This patch provides two new API for each filter to use:
tcf_exts_get_net() and tcf_exts_put_net(). And all filters now can
use the following pattern:

void __destroy_filter() {
  tcf_exts_destroy();
  tcf_exts_put_net();  // <== release netns refcnt
  kfree();
}
void some_work() {
  rtnl_lock();
  __destroy_filter();
  rtnl_unlock();
}
void some_rcu_callback() {
  tcf_queue_work(some_work);
}

if (tcf_exts_get_net())  // <== hold netns refcnt
  call_rcu(some_rcu_callback);
else
  __destroy_filter();

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
Jiri Pirko
c7eb7d7230 net: sched: introduce chain_head_change callback
Add a callback that is to be called whenever head of the chain changes.
Also provide a callback for the default case when the caller gets a
block using non-extended getter.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-03 21:57:23 +09:00
Cong Wang
8f918d3ff4 net_sched: check NULL in tcf_block_put()
Callers of tcf_block_put() could pass NULL so
we can't use block->q before checking if block is
NULL or not.

tcf_block_put_ext() callers are fine, it is always
non-NULL.

Fixes: 8c4083b30e ("net: sched: add block bind/unbind notif. and extended block_get/put")
Reported-by: Dave Taht <dave.taht@gmail.com>
Cc: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-03 21:31:15 +09:00
Jiri Pirko
4bb1b116b7 net: sched: move block offload unbind after all chains are flushed
Currently, the offload unbind is done before the chains are flushed.
That causes driver to unregister block callback before it can get all
the callback calls done during flush, leaving the offloaded tps inside
the HW. So fix the order to prevent this situation and restore the
original behaviour.

Reported-by: Alexander Duyck <alexander.duyck@gmail.com>
Reported-by: Jakub Kicinski <kubakici@wp.pl>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-03 15:46:15 +09:00
Jiri Pirko
7612fb0387 net: sched: remove tc_can_offload check from egdev call
Since the only user, mlx5 driver does the check in
mlx5e_setup_tc_block_cb, no need to check here.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-02 16:10:39 +09:00
Jiri Pirko
44ae12a768 net: sched: move the can_offload check from binding phase to rule insertion phase
This restores the original behaviour before the block callbacks were
introduced. Allow the drivers to do binding of block always, no matter
if the NETIF_F_HW_TC feature is on or off. Move the check to the block
callback which is called for rule insertion.

Reported-by: Alexander Duyck <alexander.duyck@gmail.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-02 16:10:39 +09:00
David S. Miller
ed29668d1a Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Smooth Cong Wang's bug fix into 'net-next'.  Basically put
the bulk of the tcf_block_put() logic from 'net' into
tcf_block_put_ext(), but after the offload unbind.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-02 15:23:39 +09:00
Cong Wang
822e86d997 net_sched: remove tcf_block_put_deferred()
In commit 7aa0045dad ("net_sched: introduce a workqueue for RCU callbacks of tc filter")
I defer tcf_chain_flush() to a workqueue, this causes a use-after-free
because qdisc is already destroyed after we queue this work.

The tcf_block_put_deferred() is no longer necessary after we get RTNL
for each tc filter destroy work, no others could jump in at this point.
Same for tcf_chain_hold(), we are fully serialized now.

This also reduces one indirection therefore makes the code more
readable. Note this brings back a rcu_barrier(), however comparing
to the code prior to commit 7aa0045dad we still reduced one
rcu_barrier(). For net-next, we can consider to refcnt tcf block to
avoid it.

Fixes: 7aa0045dad ("net_sched: introduce a workqueue for RCU callbacks of tc filter")
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Pirko <jiri@resnulli.us>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-31 11:06:01 +09:00
David S. Miller
e1ea2f9856 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Several conflicts here.

NFP driver bug fix adding nfp_netdev_is_nfp_repr() check to
nfp_fl_output() needed some adjustments because the code block is in
an else block now.

Parallel additions to net/pkt_cls.h and net/sch_generic.h

A bug fix in __tcp_retransmit_skb() conflicted with some of
the rbtree changes in net-next.

The tc action RCU callback fixes in 'net' had some overlap with some
of the recent tcf_block reworking.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-30 21:09:24 +09:00
Cong Wang
2d132eba1d net_sched: add rtnl assertion to tcf_exts_destroy()
After previous patches, it is now safe to claim that
tcf_exts_destroy() is always called with RTNL lock.

Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Pirko <jiri@resnulli.us>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-29 22:49:31 +09:00
Cong Wang
7aa0045dad net_sched: introduce a workqueue for RCU callbacks of tc filter
This patch introduces a dedicated workqueue for tc filters
so that each tc filter's RCU callback could defer their
action destroy work to this workqueue. The helper
tcf_queue_work() is introduced for them to use.

Because we hold RTNL lock when calling tcf_block_put(), we
can not simply flush works inside it, therefore we have to
defer it again to this workqueue and make sure all flying RCU
callbacks have already queued their work before this one, in
other words, to ensure this is the last one to execute to
prevent any use-after-free.

On the other hand, this makes tcf_block_put() ugly and
harder to understand. Since David and Eric strongly dislike
adding synchronize_rcu(), this is probably the only
solution that could make everyone happy.

Please also see the code comments below.

Reported-by: Chris Mi <chrism@mellanox.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Pirko <jiri@resnulli.us>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-29 22:49:30 +09:00
Or Gerlitz
9d452cebd7 net/sched: Fix actions list corruption when adding offloaded tc flows
Prior to commit b3f55bdda8, the networking core doesn't wire an in-place
actions list the when the low level driver is called to offload the flow,
but all low level drivers do that (call tcf_exts_to_list()) in their
offloading "add" logic.

Now, the in-place list is set in the core which goes over the list in a loop,
but also by the hw driver when their offloading code is invoked indirectly:

	cls_xxx add flow -> tc_setup_cb_call -> tc_exts_setup_cb_egdev_call -> hw driver

which messes up the core list instance upon driver return. Fix that by avoiding
in-place list on the net core code that deals with adding flows.

Fixes: b3f55bdda8 ('net: sched: introduce per-egress action device callbacks')
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-24 19:00:54 +09:00
Jiri Pirko
208c0f4b52 net: sched: use tc_setup_cb_call to call per-block callbacks
Extend the tc_setup_cb_call entrypoint function originally used only for
action egress devices callbacks to call per-block callbacks as well.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-21 03:04:07 +01:00
Jiri Pirko
acb674428c net: sched: introduce per-block callbacks
Introduce infrastructure that allows drivers to register callbacks that
are called whenever tc would offload inserted rule for a specific block.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-21 03:04:06 +01:00
Jiri Pirko
8c4083b30e net: sched: add block bind/unbind notif. and extended block_get/put
Introduce new type of ndo_setup_tc message to propage binding/unbinding
of a block to driver. Call this ndo whenever qdisc gets/puts a block.
Alongside with this, there's need to propagate binder type from qdisc
code down to the notifier. So introduce extended variants of
block_get/put in order to pass this info.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-21 03:04:06 +01:00
Jiri Pirko
a10fa20101 net: sched: propagate q and parent from caller down to tcf_fill_node
The callers have this info, they will pass it down to tcf_fill_node.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-16 21:00:41 +01:00
Jiri Pirko
855319becb net: sched: store net pointer in block and introduce qdisc_net helper
Store net pointer in the block structure. Along the way, introduce
qdisc_net helper which allows to easily obtain net pointer for
qdisc instance.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-16 21:00:40 +01:00
Jiri Pirko
69d78ef25c net: sched: store Qdisc pointer in struct block
Prepare for removal of tp->q and store Qdisc pointer in the block
structure.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-16 21:00:40 +01:00
Jiri Pirko
7578d7b45e net: sched: remove unused tcf_exts_get_dev helper and cls_flower->egress_dev
The helper and the struct field ares no longer used by any code,
so remove them.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-11 20:15:43 -07:00
Jiri Pirko
717503b9cf net: sched: convert cls_flower->egress_dev users to tc_setup_cb_egdev infra
The only user of cls_flower->egress_dev is mlx5. So do the conversion
there alongside with the code originating the call in cls_flower
function fl_hw_replace_filter to the newly introduced egress device
callback infrastucture.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-11 20:15:43 -07:00
Jiri Pirko
b3f55bdda8 net: sched: introduce per-egress action device callbacks
Introduce infrastructure that allows drivers to register callbacks that
are called whenever tc would offload inserted rule and specified device
acts as tc action egress device.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-11 20:15:43 -07:00
Jiri Pirko
843e79d05a net: sched: make tc_action_ops->get_dev return dev and avoid passing net
Return dev directly, NULL if not possible. That is enough.

Makes no sense to pass struct net * to get_dev op, as there is only one
net possible, the one the action was created in. So just store it in
mirred priv and use directly.

Rename the mirred op callback function.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-11 20:15:42 -07:00
Cong Wang
1697c4bb52 net_sched: carefully handle tcf_block_put()
As pointed out by Jiri, there is still a race condition between
tcf_block_put() and tcf_chain_destroy() in a RCU callback. There
is no way to make it correct without proper locking or synchronization,
because both operate on a shared list.

Locking is hard, because the only lock we can pick here is a spinlock,
however, in tc_dump_tfilter() we iterate this list with a sleeping
function called (tcf_chain_dump()), which makes using a lock to protect
chain_list almost impossible.

Jiri suggested the idea of holding a refcnt before flushing, this works
because it guarantees us there would be no parallel tcf_chain_destroy()
during the loop, therefore the race condition is gone. But we have to
be very careful with proper synchronization with RCU callbacks.

Suggested-by: Jiri Pirko <jiri@mellanox.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-12 20:41:02 -07:00
Cong Wang
e2ef754453 net_sched: fix reference counting of tc filter chain
This patch fixes the following ugliness of tc filter chain refcnt:

a) tp proto should hold a refcnt to the chain too. This significantly
   simplifies the logic.

b) Chain 0 is no longer special, it is created with refcnt=1 like any
   other chains. All the ugliness in tcf_chain_put() can be gone!

c) No need to handle the flushing oddly, because block still holds
   chain 0, it can not be released, this guarantees block is the last
   user.

d) The race condition with RCU callbacks is easier to handle with just
   a rcu_barrier(). Much easier to understand, nothing to hide. Thanks
   to the previous patch. Please see also the comments in code.

e) Make the code understandable by humans, much less error-prone.

Fixes: 744a4cf63e ("net: sched: fix use after free when tcf_chain_destroy is called multiple times")
Fixes: 5bc1701881 ("net: sched: introduce multichain support for filters")
Cc: Jiri Pirko <jiri@mellanox.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-12 20:41:02 -07:00
Jiri Pirko
80532384af net: sched: fix memleak for chain zero
There's a memleak happening for chain 0. The thing is, chain 0 needs to
be always present, not created on demand. Therefore tcf_block_get upon
creation of block calls the tcf_chain_create function directly. The
chain is created with refcnt == 1, which is not correct in this case and
causes the memleak. So move the refcnt increment into tcf_chain_get
function even for the case when chain needs to be created.

Reported-by: Jakub Kicinski <kubakici@wp.pl>
Fixes: 5bc1701881 ("net: sched: introduce multichain support for filters")
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Tested-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-07 19:17:20 -07:00
David S. Miller
6026e043d0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Three cases of simple overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-01 17:42:05 -07:00
WANG Cong
143976ce99 net_sched: remove tc class reference counting
For TC classes, their ->get() and ->put() are always paired, and the
reference counting is completely useless, because:

1) For class modification and dumping paths, we already hold RTNL lock,
   so all of these ->get(),->change(),->put() are atomic.

2) For filter bindiing/unbinding, we use other reference counter than
   this one, and they should have RTNL lock too.

3) For ->qlen_notify(), it is special because it is called on ->enqueue()
   path, but we already hold qdisc tree lock there, and we hold this
   tree lock when graft or delete the class too, so it should not be gone
   or changed until we release the tree lock.

Therefore, this patch removes ->get() and ->put(), but:

1) Adds a new ->find() to find the pointer to a class by classid, no
   refcnt.

2) Move the original class destroy upon the last refcnt into ->delete(),
   right after releasing tree lock. This is fine because the class is
   already removed from hash when holding the lock.

For those who also use ->put() as ->unbind(), just rename them to reflect
this change.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-25 17:19:10 -07:00
Jiri Pirko
30d65e8f96 net: sched: don't do tcf_chain_flush from tcf_chain_destroy
tcf_chain_flush needs to be called with RTNL. However, on
free_tcf->
 tcf_action_goto_chain_fini->
  tcf_chain_put->
   tcf_chain_destroy->
    tcf_chain_flush
callpath, it is called without RTNL.
This issue was notified by following warning:

[  155.599052] WARNING: suspicious RCU usage
[  155.603165] 4.13.0-rc5jiri+ #54 Not tainted
[  155.607456] -----------------------------
[  155.611561] net/sched/cls_api.c:195 suspicious rcu_dereference_protected() usage!

Since on this callpath, the chain is guaranteed to be already empty
by check in tcf_chain_put, move the tcf_chain_flush call out and call it
only where it is needed - into tcf_block_put.

Fixes: db50514f9a ("net: sched: add termination action to allow goto chain")
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-22 14:39:58 -07:00
Jiri Pirko
744a4cf63e net: sched: fix use after free when tcf_chain_destroy is called multiple times
The goto_chain termination action takes a reference of a chain. In that
case, there is an issue when block_put is called tcf_chain_destroy
directly. The follo-up call of tcf_chain_put by goto_chain action free
works with memory that is already freed. This was caught by kasan:

[  220.337908] BUG: KASAN: use-after-free in tcf_chain_put+0x1b/0x50
[  220.344103] Read of size 4 at addr ffff88036d1f2cec by task systemd-journal/261
[  220.353047] CPU: 0 PID: 261 Comm: systemd-journal Not tainted 4.13.0-rc5jiri+ #54
[  220.360661] Hardware name: Mellanox Technologies Ltd. Mellanox switch/Mellanox x86 mezzanine board, BIOS 4.6.5 08/02/2016
[  220.371784] Call Trace:
[  220.374290]  <IRQ>
[  220.376355]  dump_stack+0xd5/0x150
[  220.391485]  print_address_description+0x86/0x410
[  220.396308]  kasan_report+0x181/0x4c0
[  220.415211]  tcf_chain_put+0x1b/0x50
[  220.418949]  free_tcf+0x95/0xc0

So allow tcf_chain_destroy to be called multiple times, free only in
case the reference count drops to 0.

Fixes: 5bc1701881 ("net: sched: introduce multichain support for filters")
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-22 14:39:58 -07:00
David S. Miller
e2a7c34fb2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-08-21 17:06:42 -07:00