Commit Graph

2036 Commits

Author SHA1 Message Date
Cong Wang
039af9c66b net_sched: switch to exit_batch for action pernet ops
Since we now hold RTNL lock in tc_action_net_exit(), it is good to
batch them to speedup tc action dismantle.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-13 13:58:41 -05:00
David S. Miller
51e18a453f Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflict was two parallel additions of include files to sch_generic.c,
no biggie.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-09 22:09:55 -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
John Fastabend
c5ad119fb6 net: sched: pfifo_fast use skb_array
This converts the pfifo_fast qdisc to use the skb_array data structure
and set the lockless qdisc bit. pfifo_fast is the first qdisc to support
the lockless bit that can be a child of a qdisc requiring locking. So
we add logic to clear the lock bit on initialization in these cases when
the qdisc graft operation occurs.

This also removes the logic used to pick the next band to dequeue from
and instead just checks a per priority array for packets from top priority
to lowest. This might need to be a bit more clever but seems to work
for now.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-08 13:32:26 -05:00
John Fastabend
ce679e8df7 net: sched: add support for TCQ_F_NOLOCK subqueues to sch_mqprio
The sch_mqprio qdisc creates a sub-qdisc per tx queue which are then
called independently for enqueue and dequeue operations. However
statistics are aggregated and pushed up to the "master" qdisc.

This patch adds support for any of the sub-qdiscs to be per cpu
statistic qdiscs. To handle this case add a check when calculating
stats and aggregate the per cpu stats if needed.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-08 13:32:26 -05:00
John Fastabend
b01ac095c7 net: sched: add support for TCQ_F_NOLOCK subqueues to sch_mq
The sch_mq qdisc creates a sub-qdisc per tx queue which are then
called independently for enqueue and dequeue operations. However
statistics are aggregated and pushed up to the "master" qdisc.

This patch adds support for any of the sub-qdiscs to be per cpu
statistic qdiscs. To handle this case add a check when calculating
stats and aggregate the per cpu stats if needed.

Also exports __gnet_stats_copy_queue() to use as a helper function.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-08 13:32:26 -05:00
John Fastabend
7e66016f2c net: sched: helpers to sum qlen and qlen for per cpu logic
Add qdisc qlen helper routines for lockless qdiscs to use.

The qdisc qlen is no longer used in the hotpath but it is reported
via stats query on the qdisc so it still needs to be tracked. This
adds the per cpu operations needed along with a helper to return
the summation of per cpu stats.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-08 13:32:26 -05:00
John Fastabend
fd8e8d1a77 net: sched: check for frozen queue before skb_bad_txq check
I can not think of any reason to pull the bad txq skb off the qdisc if
the txq we plan to send this on is still frozen. So check for frozen
queue first and abort before dequeuing either skb_bad_txq skb or
normal qdisc dequeue() skb.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-08 13:32:26 -05:00
John Fastabend
70e57d5e3f net: sched: use skb list for skb_bad_tx
Similar to how gso is handled use skb list for skb_bad_tx this is
required with lockless qdiscs because we may have multiple cores
attempting to push skbs into skb_bad_tx concurrently

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-08 13:32:26 -05:00
John Fastabend
7bbde83b18 net: sched: drop qdisc_reset from dev_graft_qdisc
In qdisc_graft_qdisc a "new" qdisc is attached and the 'qdisc_destroy'
operation is called on the old qdisc. The destroy operation will wait
a rcu grace period and call qdisc_rcu_free(). At which point
gso_cpu_skb is free'd along with all stats so no need to zero stats
and gso_cpu_skb from the graft operation itself.

Further after dropping the qdisc locks we can not continue to call
qdisc_reset before waiting an rcu grace period so that the qdisc is
detached from all cpus. By removing the qdisc_reset() here we get
the correct property of waiting an rcu grace period and letting the
qdisc_destroy operation clean up the qdisc correctly.

Note, a refcnt greater than 1 would cause the destroy operation to
be aborted however if this ever happened the reference to the qdisc
would be lost and we would have a memory leak.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-08 13:32:25 -05:00
John Fastabend
a53851e2c3 net: sched: explicit locking in gso_cpu fallback
This work is preparing the qdisc layer to support egress lockless
qdiscs. If we are running the egress qdisc lockless in the case we
overrun the netdev, for whatever reason, the netdev returns a busy
error code and the skb is parked on the gso_skb pointer. With many
cores all hitting this case at once its possible to have multiple
sk_buffs here so we turn gso_skb into a queue.

This should be the edge case and if we see this frequently then
the netdev/qdisc layer needs to back off.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-08 13:32:25 -05:00
John Fastabend
d59f5ffa59 net: sched: a dflt qdisc may be used with per cpu stats
Enable dflt qdisc support for per cpu stats before this patch a dflt
qdisc was required to use the global statistics qstats and bstats.

This adds a static flags field to qdisc_ops that is propagated
into qdisc->flags in qdisc allocate call. This allows the allocation
block to completely allocate the qdisc object so we don't have
dangling allocations after qdisc init.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-08 13:32:25 -05:00
John Fastabend
29b86cdac0 net: sched: remove remaining uses for qdisc_qlen in xmit path
sch_direct_xmit() uses qdisc_qlen as a return value but all call sites
of the routine only check if it is zero or not. Simplify the logic so
that we don't need to return an actual queue length value.

This introduces a case now where sch_direct_xmit would have returned
a qlen of zero but now it returns true. However in this case all
call sites of sch_direct_xmit will implement a dequeue() and get
a null skb and abort. This trades tracking qlen in the hotpath for
an extra dequeue operation. Overall this seems to be good for
performance.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-08 13:32:25 -05:00
John Fastabend
6b3ba9146f net: sched: allow qdiscs to handle locking
This patch adds a flag for queueing disciplines to indicate the stack
does not need to use the qdisc lock to protect operations. This can
be used to build lockless scheduling algorithms and improving
performance.

The flag is checked in the tx path and the qdisc lock is only taken
if it is not set. For now use a conditional if statement. Later we
could be more aggressive if it proves worthwhile and use a static key
or wrap this in a likely().

Also the lockless case drops the TCQ_F_CAN_BYPASS logic. The reason
for this is synchronizing a qlen counter across threads proves to
cost more than doing the enqueue/dequeue operations when tested with
pktgen.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-08 13:32:25 -05:00
John Fastabend
6c148184b5 net: sched: cleanup qdisc_run and __qdisc_run semantics
Currently __qdisc_run calls qdisc_run_end() but does not call
qdisc_run_begin(). This makes it hard to track pairs of
qdisc_run_{begin,end} across function calls.

To simplify reading these code paths this patch moves begin/end calls
into qdisc_run().

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-08 13:32:25 -05:00
Chris Dion
32d3e51a82 net_sched: use macvlan real dev trans_start in dev_trans_start()
Macvlan devices are similar to vlans and do not update their
own trans_start. In order for arp monitoring to work for a bond device
when the slaves are macvlans, obtain its real device.

Signed-off-by: Chris Dion <christopher.dion@dell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-06 15:34:10 -05:00
Cong Wang
4bee00eb25 act_mirred: get rid of mirred_list_lock spinlock
TC actions are no longer freed in RCU callbacks and we should
always have RTNL lock, so this spinlock is no longer needed.

Cc: Eric Dumazet <eric.dumazet@gmail.com>
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>
2017-12-06 14:50:13 -05:00
Cong Wang
9f8a739e72 act_mirred: get rid of tcfm_ifindex from struct tcf_mirred
tcfm_dev always points to the correct netdev and we already
hold a refcnt, so no need to use tcfm_ifindex to lookup again.

If we would support moving target netdev across netns, using
pointer would be better than ifindex.

This also fixes dumping obsolete ifindex, now after the
target device is gone we just dump 0 as ifindex.

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>
2017-12-06 14:50:13 -05:00
Cong Wang
9a63b255df net_sched: remove unused parameter from act cleanup ops
No one actually uses it.

Cc: Jiri Pirko <jiri@mellanox.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-05 18:07:58 -05:00
Alexander Aring
54160ef6ec net: sched: sch_api: rearrange init handling
This patch fixes the following checkpatch error:

ERROR: do not use assignment in if condition

by rearranging the if condition to execute init callback only if init
callback exists. The whole setup afterwards is called in any case,
doesn't matter if init callback is set or not. This patch has the same
behaviour as before, just without assign err variable in if condition.
It also makes the code easier to read.

Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-05 15:04:27 -05:00
Alexander Aring
0ac4bd68ab net: sched: sch_api: fix code style issues
This patch fix checkpatch issues for upcomming patches according to the
sched api file. It changes checking on null pointer, remove unnecessary
brackets, add variable names for parameters and adjust 80 char width.

Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-05 15:04:27 -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
Nogah Frankel
8afa10cbe2 net_sched: red: Avoid illegal values
Check the qmin & qmax values doesn't overflow for the given Wlog value.
Check that qmin <= qmax.

Fixes: a783474591 ("[PKT_SCHED]: Generic RED layer")
Signed-off-by: Nogah Frankel <nogahf@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-05 14:37:13 -05:00
Simon Horman
62b32379fd flow_dissector: dissect tunnel info outside __skb_flow_dissect()
Move dissection of tunnel info to outside of the main flow dissection
function, __skb_flow_dissect(). The sole user of this feature, the flower
classifier, is updated to call tunnel info dissection directly, using
skb_flow_dissect_tunnel_info().

This results in a slightly less complex implementation of
__skb_flow_dissect(), in particular removing logic from that call path
which is not used by the majority of users. The expense of this is borne by
the flower classifier which now has to make an extra call for tunnel info
dissection.

This patch should not result in any behavioural change.

Signed-off-by: Simon Horman <simon.horman@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-05 12:09:18 -05:00
Cong Wang
90a6ec8535 act_sample: get rid of tcf_sample_cleanup_rcu()
Similar to commit d7fb60b9ca ("net_sched: get rid of tcfa_rcu"),
TC actions don't need to respect RCU grace period, because it
is either just detached from tc filter (standalone case) or
it is removed together with tc filter (bound case) in which case
RCU grace period is already respected at filter layer.

Fixes: 5c5670fae4 ("net/sched: Introduce sample tc action")
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Cc: Yotam Gigi <yotamg@mellanox.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-30 10:19:17 -05:00
Jiri Pirko
d51aae68b1 net: sched: cbq: create block for q->link.block
q->link.block is not initialized, that leads to EINVAL when one tries to
add filter there. So initialize it properly.

This can be reproduced by:
$ tc qdisc add dev eth0 root handle 1: cbq avpkt 1000 rate 1000Mbit bandwidth 1000Mbit
$ tc filter add dev eth0 parent 1: protocol ip prio 100 u32 match ip protocol 0 0x00 flowid 1:1

Reported-by: Jaroslav Aster <jaster@redhat.com>
Reported-by: Ivan Vecera <ivecera@redhat.com>
Fixes: 6529eaba33 ("net: sched: introduce tcf block infractructure")
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Eelco Chaudron <echaudro@redhat.com>
Reviewed-by: Ivan Vecera <ivecera@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-28 16:04:26 -05:00
Paolo Abeni
f85729d07c sch_sfq: fix null pointer dereference at timer expiration
While converting sch_sfq to use timer_setup(), the commit cdeabbb881
("net: sched: Convert timers to use timer_setup()") forgot to
initialize the 'sch' field. As a result, the timer callback tries to
dereference a NULL pointer, and the kernel does oops.

Fix it initializing such field at qdisc creation time.

Fixes: cdeabbb881 ("net: sched: Convert timers to use timer_setup()")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-28 15:54:05 -05:00
Jakub Kicinski
25415cec50 cls_bpf: don't decrement net's refcount when offload fails
When cls_bpf offload was added it seemed like a good idea to
call cls_bpf_delete_prog() instead of extending the error
handling path, since the software state is fully initialized
at that point.  This handling of errors without jumping to
the end of the function is error prone, as proven by later
commit missing that extra call to __cls_bpf_delete_prog().

__cls_bpf_delete_prog() is now expected to be invoked with
a reference on exts->net or the field zeroed out.  The call
on the offload's error patch does not fullfil this requirement,
leading to each error stealing a reference on net namespace.

Create a function undoing what cls_bpf_set_parms() did and
use it from __cls_bpf_delete_prog() and the error path.

Fixes: aae2c35ec8 ("cls_bpf: use tcf_exts_get_net() before call_rcu()")
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-28 15:49:44 -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
David S. Miller
e4be7baba8 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2017-11-23

The following pull-request contains BPF updates for your *net* tree.

The main changes are:

1) Several BPF offloading fixes, from Jakub. Among others:

    - Limit offload to cls_bpf and XDP program types only.
    - Move device validation into the driver and don't make
      any assumptions about the device in the classifier due
      to shared blocks semantics.
    - Don't pass offloaded XDP program into the driver when
      it should be run in native XDP instead. Offloaded ones
      are not JITed for the host in such cases.
    - Don't destroy device offload state when moved to
      another namespace.
    - Revert dumping offload info into user space for now,
      since ifindex alone is not sufficient. This will be
      redone properly for bpf-next tree.

2) Fix test_verifier to avoid using bpf_probe_write_user()
   helper in test cases, since it's dumping a warning into
   kernel log which may confuse users when only running tests.
   Switch to use bpf_trace_printk() instead, from Yonghong.

3) Several fixes for correcting ARG_CONST_SIZE_OR_ZERO semantics
   before it becomes uabi, from Gianluca. More specifically:

    - Add a type ARG_PTR_TO_MEM_OR_NULL that is used only
      by bpf_csum_diff(), where the argument is either a
      valid pointer or NULL. The subsequent ARG_CONST_SIZE_OR_ZERO
      then enforces a valid pointer in case of non-0 size
      or a valid pointer or NULL in case of size 0. Given
      that, the semantics for ARG_PTR_TO_MEM in combination
      with ARG_CONST_SIZE_OR_ZERO are now such that in case
      of size 0, the pointer must always be valid and cannot
      be NULL. This fix in semantics allows for bpf_probe_read()
      to drop the recently added size == 0 check in the helper
      that would become part of uabi otherwise once released.
      At the same time we can then fix bpf_probe_read_str() and
      bpf_perf_event_output() to use ARG_CONST_SIZE_OR_ZERO
      instead of ARG_CONST_SIZE in order to fix recently
      reported issues by Arnaldo et al, where LLVM optimizes
      two boundary checks into a single one for unknown
      variables where the verifier looses track of the variable
      bounds and thus rejects valid programs otherwise.

4) A fix for the verifier for the case when it detects
   comparison of two constants where the branch is guaranteed
   to not be taken at runtime. Verifier will rightfully prune
   the exploration of such paths, but we still pass the program
   to JITs, where they would complain about using reserved
   fields, etc. Track such dead instructions and sanitize
   them with mov r0,r0. Rejection is not possible since LLVM
   may generate them for valid C code and doesn't do as much
   data flow analysis as verifier. For bpf-next we might
   implement removal of such dead code and adjust branches
   instead. Fix from Alexei.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-24 02:33:01 +09:00
Willem de Bruijn
0c19f846d5 net: accept UFO datagrams from tuntap and packet
Tuntap and similar devices can inject GSO packets. Accept type
VIRTIO_NET_HDR_GSO_UDP, even though not generating UFO natively.

Processes are expected to use feature negotiation such as TUNSETOFFLOAD
to detect supported offload types and refrain from injecting other
packets. This process breaks down with live migration: guest kernels
do not renegotiate flags, so destination hosts need to expose all
features that the source host does.

Partially revert the UFO removal from 182e0b6b5846~1..d9d30adf5677.
This patch introduces nearly(*) no new code to simplify verification.
It brings back verbatim tuntap UFO negotiation, VIRTIO_NET_HDR_GSO_UDP
insertion and software UFO segmentation.

It does not reinstate protocol stack support, hardware offload
(NETIF_F_UFO), SKB_GSO_UDP tunneling in SKB_GSO_SOFTWARE or reception
of VIRTIO_NET_HDR_GSO_UDP packets in tuntap.

To support SKB_GSO_UDP reappearing in the stack, also reinstate
logic in act_csum and openvswitch. Achieve equivalence with v4.13 HEAD
by squashing in commit 939912216f ("net: skb_needs_check() removes
CHECKSUM_UNNECESSARY check for tx.") and reverting commit 8d63bee643
("net: avoid skb_warn_bad_offload false positives on UFO").

(*) To avoid having to bring back skb_shinfo(skb)->ip6_frag_id,
ipv6_proxy_select_ident is changed to return a __be32 and this is
assigned directly to the frag_hdr. Also, SKB_GSO_UDP is inserted
at the end of the enum to minimize code churn.

Tested
  Booted a v4.13 guest kernel with QEMU. On a host kernel before this
  patch `ethtool -k eth0` shows UFO disabled. After the patch, it is
  enabled, same as on a v4.13 host kernel.

  A UFO packet sent from the guest appears on the tap device:
    host:
      nc -l -p -u 8000 &
      tcpdump -n -i tap0

    guest:
      dd if=/dev/zero of=payload.txt bs=1 count=2000
      nc -u 192.16.1.1 8000 < payload.txt

  Direct tap to tap transmission of VIRTIO_NET_HDR_GSO_UDP succeeds,
  packets arriving fragmented:

    ./with_tap_pair.sh ./tap_send_ufo tap0 tap1
    (from https://github.com/wdebruij/kerneltools/tree/master/tests)

Changes
  v1 -> v2
    - simplified set_offload change (review comment)
    - documented test procedure

Link: http://lkml.kernel.org/r/<CAF=yD-LuUeDuL9YWPJD9ykOZ0QCjNeznPDr6whqZ9NGMNF12Mw@mail.gmail.com>
Fixes: fb652fdfe8 ("macvlan/macvtap: Remove NETIF_F_UFO advertisement.")
Reported-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-24 01:37:35 +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
Jakub Kicinski
288b3de55a bpf: offload: move offload device validation out to the drivers
With TC shared block changes we can't depend on correct netdev
pointer being available in cls_bpf.  Move the device validation
to the driver.  Core will only make sure that offloaded programs
are always attached in the driver (or in HW by the driver).  We
trust that drivers which implement offload callbacks will perform
necessary checks.

Moving the checks to the driver is generally a useful thing,
in practice the check should be against a switchdev instance,
not a netdev, given that most ASICs will probably allow using
the same program on many ports.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-21 00:37:35 +01:00
Stephen Hemminger
9b0ed89172 netem: remove unnecessary 64 bit modulus
Fix compilation on 32 bit platforms (where doing modulus operation
with 64 bit requires extra glibc functions) by truncation.
The jitter for table distribution is limited to a 32 bit value
because random numbers are scaled as 32 bit value.

Also fix some whitespace.

Fixes: 99803171ef ("netem: add uapi to express delay and jitter in nanoseconds")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-15 14:14:16 +09:00
Stephen Hemminger
bce552fd6f netem: use 64 bit divide by rate
Since times are now expressed in nanosecond, need to now do
true 64 bit divide. Old code would truncate rate at 32 bits.
Rename function to better express current usage.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-15 14:14:16 +09:00
Andrew Morton
ee9d3429c0 net/sched/sch_red.c: work around gcc-4.4.4 anon union initializer issue
gcc-4.4.4 (at lest) has issues with initializers and anonymous unions:

net/sched/sch_red.c: In function 'red_dump_offload':
net/sched/sch_red.c:282: error: unknown field 'stats' specified in initializer
net/sched/sch_red.c:282: warning: initialization makes integer from pointer without a cast
net/sched/sch_red.c:283: error: unknown field 'stats' specified in initializer
net/sched/sch_red.c:283: warning: initialization makes integer from pointer without a cast
net/sched/sch_red.c: In function 'red_dump_stats':
net/sched/sch_red.c:352: error: unknown field 'xstats' specified in initializer
net/sched/sch_red.c:352: warning: initialization makes integer from pointer without a cast

Work around this.

Fixes: 602f3baf22 ("net_sch: red: Add offload ability to RED qdisc")
Cc: Nogah Frankel <nogahf@mellanox.com>
Cc: Jiri Pirko <jiri@mellanox.com>
Cc: Simon Horman <simon.horman@netronome.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-13 10:33:07 +09:00
Dave Taht
836af83b54 netem: support delivering packets in delayed time slots
Slotting is a crude approximation of the behaviors of shared media such
as cable, wifi, and LTE, which gather up a bunch of packets within a
varying delay window and deliver them, relative to that, nearly all at
once.

It works within the existing loss, duplication, jitter and delay
parameters of netem. Some amount of inherent latency must be specified,
regardless.

The new "slot" parameter specifies a minimum and maximum delay between
transmission attempts.

The "bytes" and "packets" parameters can be used to limit the amount of
information transferred per slot.

Examples of use:

tc qdisc add dev eth0 root netem delay 200us \
         slot 800us 10ms bytes 64k packets 42

A more correct example, using stacked netem instances and a packet limit
to emulate a tail drop wifi queue with slots and variable packet
delivery, with a 200Mbit isochronous underlying rate, and 20ms path
delay:

tc qdisc add dev eth0 root handle 1: netem delay 20ms rate 200mbit \
         limit 10000
tc qdisc add dev eth0 parent 1:1 handle 10:1 netem delay 200us \
         slot 800us 10ms bytes 64k packets 42 limit 512

Signed-off-by: Dave Taht <dave.taht@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-13 10:15:47 +09:00
Dave Taht
99803171ef netem: add uapi to express delay and jitter in nanoseconds
netem userspace has long relied on a horrible /proc/net/psched hack
to translate the current notion of "ticks" to nanoseconds.

Expressing latency and jitter instead, in well defined nanoseconds,
increases the dynamic range of emulated delays and jitter in netem.

It will also ease a transition where reducing a tick to nsec
equivalence would constrain the max delay in prior versions of
netem to only 4.3 seconds.

Signed-off-by: Dave Taht <dave.taht@gmail.com>
Suggested-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-13 10:15:47 +09:00
Dave Taht
112f9cb656 netem: convert to qdisc_watchdog_schedule_ns
Upgrade the internal netem scheduler to use nanoseconds rather than
ticks throughout.

Convert to and from the std "ticks" userspace api automatically,
while allowing for finer grained scheduling to take place.

Signed-off-by: Dave Taht <dave.taht@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-13 10:15:47 +09:00
Manish Kurup
4c5b9d9642 act_vlan: VLAN action rewrite to use RCU lock/unlock and update
Using a spinlock in the VLAN action causes performance issues when the VLAN
action is used on multiple cores. Rewrote the VLAN action to use RCU read
locking for reads and updates instead.
All functions now use an RCU dereferenced pointer to access the VLAN action
context. Modified helper functions used by other modules, to use the RCU as
opposed to directly accessing the structure.

Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Manish Kurup <manish.kurup@verizon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-10 15:32:20 +09:00
Manish Kurup
e0496cbbf8 act_vlan: Change stats update to use per-core stats
The VLAN action maintains one set of stats across all cores, and uses a
spinlock to synchronize updates to it from the same. Changed this to use a
per-CPU stats context instead.
This change will result in better performance.

Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Manish Kurup <manish.kurup@verizon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-10 15:32:20 +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
35c55fc156 cls_u32: use tcf_exts_get_net() before call_rcu()
Hold netns refcnt before call_rcu() and release it after
the tcf_exts_destroy() is done.

Note, on ->destroy() path we have to respect the return value
of tcf_exts_get_net(), on other paths it should always return
true, so we don't need to care.

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 10:03:10 +09:00
Cong Wang
f2b751053e cls_tcindex: use tcf_exts_get_net() before call_rcu()
Hold netns refcnt before call_rcu() and release it after
the tcf_exts_destroy() is done.

Note, on ->destroy() path we have to respect the return value
of tcf_exts_get_net(), on other paths it should always return
true, so we don't need to care.

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 10:03:10 +09:00
Cong Wang
96585063a2 cls_rsvp: use tcf_exts_get_net() before call_rcu()
Hold netns refcnt before call_rcu() and release it after
the tcf_exts_destroy() is done.

Note, on ->destroy() path we have to respect the return value
of tcf_exts_get_net(), on other paths it should always return
true, so we don't need to care.

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 10:03:10 +09:00
Cong Wang
3fd51de5e3 cls_route: use tcf_exts_get_net() before call_rcu()
Hold netns refcnt before call_rcu() and release it after
the tcf_exts_destroy() is done.

Note, on ->destroy() path we have to respect the return value
of tcf_exts_get_net(), on other paths it should always return
true, so we don't need to care.

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 10:03:10 +09:00
Cong Wang
57767e7853 cls_matchall: use tcf_exts_get_net() before call_rcu()
Hold netns refcnt before call_rcu() and release it after
the tcf_exts_destroy() is done.

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 10:03:10 +09:00
Cong Wang
d5f984f5af cls_fw: use tcf_exts_get_net() before call_rcu()
Hold netns refcnt before call_rcu() and release it after
the tcf_exts_destroy() is done.

Note, on ->destroy() path we have to respect the return value
of tcf_exts_get_net(), on other paths it should always return
true, so we don't need to care.

Cc: Lucas Bates <lucasb@mojatatu.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-09 10:03:09 +09:00
Cong Wang
0dadc117ac cls_flower: use tcf_exts_get_net() before call_rcu()
Hold netns refcnt before call_rcu() and release it after
the tcf_exts_destroy() is done.

Note, on ->destroy() path we have to respect the return value
of tcf_exts_get_net(), on other paths it should always return
true, so we don't need to care.

Cc: Lucas Bates <lucasb@mojatatu.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-09 10:03:09 +09:00
Cong Wang
22f7cec93f cls_flow: use tcf_exts_get_net() before call_rcu()
Hold netns refcnt before call_rcu() and release it after
the tcf_exts_destroy() is done.

Note, on ->destroy() path we have to respect the return value
of tcf_exts_get_net(), on other paths it should always return
true, so we don't need to care.

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