Commit Graph

5185 Commits

Author SHA1 Message Date
Jouni Malinen
6f60126521 mac80211: Fix TKIP replay protection immediately after key setup
TKIP replay protection was skipped for the very first frame received
after a new key is configured. While this is potentially needed to avoid
dropping a frame in some cases, this does leave a window for replay
attacks with group-addressed frames at the station side. Any earlier
frame sent by the AP using the same key would be accepted as a valid
frame and the internal RSC would then be updated to the TSC from that
frame. This would allow multiple previously transmitted group-addressed
frames to be replayed until the next valid new group-addressed frame
from the AP is received by the station.

Fix this by limiting the no-replay-protection exception to apply only
for the case where TSC=0, i.e., when this is for the very first frame
protected using the new key, and the local RSC had not been set to a
higher value when configuring the key (which may happen with GTK).

Signed-off-by: Jouni Malinen <j@w1.fi>
Link: https://lore.kernel.org/r/20200107153545.10934-1-j@w1.fi
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2020-01-15 09:52:12 +01:00
Orr Mazor
26ec17a1dc cfg80211: Fix radar event during another phy CAC
In case a radar event of CAC_FINISHED or RADAR_DETECTED
happens during another phy is during CAC we might need
to cancel that CAC.

If we got a radar in a channel that another phy is now
doing CAC on then the CAC should be canceled there.

If, for example, 2 phys doing CAC on the same channels,
or on comptable channels, once on of them will finish his
CAC the other might need to cancel his CAC, since it is no
longer relevant.

To fix that the commit adds an callback and implement it in
mac80211 to end CAC.
This commit also adds a call to said callback if after a radar
event we see the CAC is no longer relevant

Signed-off-by: Orr Mazor <Orr.Mazor@tandemg.com>
Reviewed-by: Sergey Matyukevich <sergey.matyukevich.os@quantenna.com>
Link: https://lore.kernel.org/r/20191222145449.15792-1-Orr.Mazor@tandemg.com
[slightly reformat/reword commit message]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2020-01-15 09:50:48 +01:00
Markus Theil
02a6144996 mac80211: mesh: restrict airtime metric to peered established plinks
The following warning is triggered every time an unestablished mesh peer
gets dumped. Checks if a peer link is established before retrieving the
airtime link metric.

[ 9563.022567] WARNING: CPU: 0 PID: 6287 at net/mac80211/mesh_hwmp.c:345
               airtime_link_metric_get+0xa2/0xb0 [mac80211]
[ 9563.022697] Hardware name: PC Engines apu2/apu2, BIOS v4.10.0.3
[ 9563.022756] RIP: 0010:airtime_link_metric_get+0xa2/0xb0 [mac80211]
[ 9563.022838] Call Trace:
[ 9563.022897]  sta_set_sinfo+0x936/0xa10 [mac80211]
[ 9563.022964]  ieee80211_dump_station+0x6d/0x90 [mac80211]
[ 9563.023062]  nl80211_dump_station+0x154/0x2a0 [cfg80211]
[ 9563.023120]  netlink_dump+0x17b/0x370
[ 9563.023130]  netlink_recvmsg+0x2a4/0x480
[ 9563.023140]  ____sys_recvmsg+0xa6/0x160
[ 9563.023154]  ___sys_recvmsg+0x93/0xe0
[ 9563.023169]  __sys_recvmsg+0x7e/0xd0
[ 9563.023210]  do_syscall_64+0x4e/0x140
[ 9563.023217]  entry_SYSCALL_64_after_hwframe+0x44/0xa9

Signed-off-by: Markus Theil <markus.theil@tu-ilmenau.de>
Link: https://lore.kernel.org/r/20191203180644.70653-1-markus.theil@tu-ilmenau.de
[rewrite commit message]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2020-01-02 14:48:32 +01:00
Toke Høiland-Jørgensen
911bde0fe5 mac80211: Turn AQL into an NL80211_EXT_FEATURE
Instead of just having an airtime flag in debugfs, turn AQL into a proper
NL80211_EXT_FEATURE, so drivers can turn it on when they are ready, and so
we also expose the presence of the feature to userspace.

This also has the effect of flipping the default, so drivers have to opt in
to using AQL instead of getting it by default with TXQs. To keep
functionality the same as pre-patch, we set this feature for ath10k (which
is where it is needed the most).

While we're at it, split out the debugfs interface so AQL gets its own
per-station debugfs file instead of using the 'airtime' file.

[Johannes:]
This effectively disables AQL for iwlwifi, where it fixes a number of
issues:
 * TSO in iwlwifi is causing underflows and associated warnings in AQL
 * HE (802.11ax) rates aren't reported properly so at HE rates, AQL could
   never have a valid estimate (it'd use 6 Mbps instead of up to 2400!)

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/r/20191212111437.224294-1-toke@redhat.com
Fixes: 3ace10f5b5 ("mac80211: Implement Airtime-based Queue Limit (AQL)")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-12-13 10:34:04 +01:00
Dan Carpenter
e548f749b0 mac80211: airtime: Fix an off by one in ieee80211_calc_rx_airtime()
This code was copied from mt76 and inherited an off by one bug from
there.  The > should be >= so that we don't read one element beyond
the end of the array.

Fixes: db3e1c40cf ("mac80211: Import airtime calculation code from mt76")
Reported-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/r/20191126120910.ftr4t7me3by32aiz@kili.mountain
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-12-13 10:08:22 +01:00
Fredrik Olofsson
753ffad3d6 mac80211: fix TID field in monitor mode transmit
Fix overwriting of the qos_ctrl.tid field for encrypted frames injected on
a monitor interface. While qos_ctrl.tid is not encrypted, it's used as an
input into the encryption algorithm so it's protected, and thus cannot be
modified after encryption. For injected frames, the encryption may already
have been done in userspace, so we cannot change any fields.

Before passing the frame to the driver, the qos_ctrl.tid field is updated
from skb->priority. Prior to dbd50a851c skb->priority was updated in
ieee80211_select_queue_80211(), but this function is no longer always
called.

Update skb->priority in ieee80211_monitor_start_xmit() so that the value
is stored, and when later code 'modifies' the TID it really sets it to
the same value as before, preserving the encryption.

Fixes: dbd50a851c ("mac80211: only allocate one queue when using iTXQs")
Signed-off-by: Fredrik Olofsson <fredrik.olofsson@anyfinetworks.com>
Link: https://lore.kernel.org/r/20191119133451.14711-1-fredrik.olofsson@anyfinetworks.com
[rewrite commit message based on our discussion]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-12-13 10:06:39 +01:00
Linus Torvalds
9a3d7fd275 Driver core patches for 5.5-rc1
Here is the "big" set of driver core patches for 5.5-rc1
 
 There's a few minor cleanups and fixes in here, but the majority of the
 patches in here fall into two buckets:
   - debugfs api cleanups and fixes
   - driver core device link support for boot dependancy issues
 
 The debugfs api cleanups are working to slowly refactor the debugfs apis
 so that it is even harder to use incorrectly.  That work has been
 happening for the past few kernel releases and will continue over time,
 it's a long-term project/goal
 
 The driver core device link support missed 5.4 by just a bit, so it's
 been sitting and baking for many months now.  It's from Saravana Kannan
 to help resolve the problems that DT-based systems have at boot time
 with dependancy graphs and kernel modules.  Turns out that no one has
 actually tried to build a generic arm64 kernel with loads of modules and
 have it "just work" for a variety of platforms (like a distro kernel)
 The big problem turned out to be a lack of depandancy information
 between different areas of DT entries, and the work here resolves that
 problem and now allows devices to boot properly, and quicker than a
 monolith kernel.
 
 All of these patches have been in linux-next for a long time with no
 reported issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here is the "big" set of driver core patches for 5.5-rc1

  There's a few minor cleanups and fixes in here, but the majority of
  the patches in here fall into two buckets:

   - debugfs api cleanups and fixes

   - driver core device link support for boot dependancy issues

  The debugfs api cleanups are working to slowly refactor the debugfs
  apis so that it is even harder to use incorrectly. That work has been
  happening for the past few kernel releases and will continue over
  time, it's a long-term project/goal

  The driver core device link support missed 5.4 by just a bit, so it's
  been sitting and baking for many months now. It's from Saravana Kannan
  to help resolve the problems that DT-based systems have at boot time
  with dependancy graphs and kernel modules. Turns out that no one has
  actually tried to build a generic arm64 kernel with loads of modules
  and have it "just work" for a variety of platforms (like a distro
  kernel). The big problem turned out to be a lack of dependency
  information between different areas of DT entries, and the work here
  resolves that problem and now allows devices to boot properly, and
  quicker than a monolith kernel.

  All of these patches have been in linux-next for a long time with no
  reported issues"

* tag 'driver-core-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (68 commits)
  tracing: Remove unnecessary DEBUG_FS dependency
  of: property: Add device link support for interrupt-parent, dmas and -gpio(s)
  debugfs: Fix !DEBUG_FS debugfs_create_automount
  of: property: Add device link support for "iommu-map"
  of: property: Fix the semantics of of_is_ancestor_of()
  i2c: of: Populate fwnode in of_i2c_get_board_info()
  drivers: base: Fix Kconfig indentation
  firmware_loader: Fix labels with comma for builtin firmware
  driver core: Allow device link operations inside sync_state()
  driver core: platform: Declare ret variable only once
  cpu-topology: declare parse_acpi_topology in <linux/arch_topology.h>
  crypto: hisilicon: no need to check return value of debugfs_create functions
  driver core: platform: use the correct callback type for bus_find_device
  firmware_class: make firmware caching configurable
  driver core: Clarify documentation for fwnode_operations.add_links()
  mailbox: tegra: Fix superfluous IRQ error message
  net: caif: Fix debugfs on 64-bit platforms
  mac80211: Use debugfs_create_xul() helper
  media: c8sectpfe: no need to check return value of debugfs_create functions
  of: property: Add device link support for iommus, mboxes and io-channels
  ...
2019-11-27 11:06:20 -08:00
Toke Høiland-Jørgensen
7a89233ac5 mac80211: Use Airtime-based Queue Limits (AQL) on packet dequeue
The previous commit added the ability to throttle stations when they queue
too much airtime in the hardware. This commit enables the functionality by
calculating the expected airtime usage of each packet that is dequeued from
the TXQs in mac80211, and accounting that as pending airtime.

The estimated airtime for each skb is stored in the tx_info, so we can
subtract the same amount from the running total when the skb is freed or
recycled. The throttling mechanism relies on this accounting to be
accurate (i.e., that we are not freeing skbs without subtracting any
airtime they were accounted for), so we put the subtraction into
ieee80211_report_used_skb(). As an optimisation, we also subtract the
airtime on regular TX completion, zeroing out the value stored in the
packet afterwards, to avoid having to do an expensive lookup of the station
from the packet data on every packet.

This patch does *not* include any mechanism to wake a throttled TXQ again,
on the assumption that this will happen anyway as a side effect of whatever
freed the skb (most commonly a TX completion).

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/r/20191119060610.76681-5-kyan@google.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-11-22 13:36:25 +01:00
Kan Yan
3ace10f5b5 mac80211: Implement Airtime-based Queue Limit (AQL)
In order for the Fq_CoDel algorithm integrated in mac80211 layer to operate
effectively to control excessive queueing latency, the CoDel algorithm
requires an accurate measure of how long packets stays in the queue, AKA
sojourn time. The sojourn time measured at the mac80211 layer doesn't
include queueing latency in the lower layer (firmware/hardware) and CoDel
expects lower layer to have a short queue. However, most 802.11ac chipsets
offload tasks such TX aggregation to firmware or hardware, thus have a deep
lower layer queue.

Without a mechanism to control the lower layer queue size, packets only
stay in mac80211 layer transiently before being sent to firmware queue.
As a result, the sojourn time measured by CoDel in the mac80211 layer is
almost always lower than the CoDel latency target, hence CoDel does little
to control the latency, even when the lower layer queue causes excessive
latency.

The Byte Queue Limits (BQL) mechanism is commonly used to address the
similar issue with wired network interface. However, this method cannot be
applied directly to the wireless network interface. "Bytes" is not a
suitable measure of queue depth in the wireless network, as the data rate
can vary dramatically from station to station in the same network, from a
few Mbps to over Gbps.

This patch implements an Airtime-based Queue Limit (AQL) to make CoDel work
effectively with wireless drivers that utilized firmware/hardware
offloading. AQL allows each txq to release just enough packets to the lower
layer to form 1-2 large aggregations to keep hardware fully utilized and
retains the rest of the frames in mac80211 layer to be controlled by the
CoDel algorithm.

Signed-off-by: Kan Yan <kyan@google.com>
[ Toke: Keep API to set pending airtime internal, fix nits in commit msg ]
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/r/20191119060610.76681-4-kyan@google.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-11-22 13:36:25 +01:00
Toke Høiland-Jørgensen
db3e1c40cf mac80211: Import airtime calculation code from mt76
Felix recently added code to calculate airtime of packets to the mt76
driver. Import this into mac80211 so we can use it for airtime queue limit
calculations.

The airtime.c file is copied verbatim from the mt76 driver, and adjusted to
be usable in mac80211. This involves:

- Switching to mac80211 data structures.
- Adding support for 160 MHz channels and HE mode.
- Moving the symbol and duration calculations around a bit to avoid
  rounding with the higher rates and longer symbol times used for HE rates.

The per-rate TX rate calculation is also split out to its own function so
it can be used directly for the AQL calculations later.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/r/20191119060610.76681-3-kyan@google.com
[fix HE_GROUP_IDX() to use 3 * bw, since there are 3 _gi values]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-11-22 13:36:25 +01:00
Thomas Pedersen
08a5bdde38 mac80211: consider QoS Null frames for STA_NULLFUNC_ACKED
Commit 7b6ddeaf27 ("mac80211: use QoS NDP for AP probing")
let STAs send QoS Null frames as PS triggers if the AP was
a QoS STA.  However, the mac80211 PS stack relies on an
interface flag IEEE80211_STA_NULLFUNC_ACKED for
determining trigger frame ACK, which was not being set for
acked non-QoS Null frames. The effect is an inability to
trigger hardware sleep via IEEE80211_CONF_PS since the QoS
Null frame was seemingly never acked.

This bug only applies to drivers which set both
IEEE80211_HW_REPORTS_TX_ACK_STATUS and
IEEE80211_HW_PS_NULLFUNC_STACK.

Detect the acked QoS Null frame to restore STA power save.

Fixes: 7b6ddeaf27 ("mac80211: use QoS NDP for AP probing")
Signed-off-by: Thomas Pedersen <thomas@adapt-ip.com>
Link: https://lore.kernel.org/r/20191119053538.25979-4-thomas@adapt-ip.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-11-22 13:36:25 +01:00
Thomas Pedersen
c90142a518 mac80211: expose HW conf flags through debugfs
This is useful during testing to eg. check the currently
configured HW power save state.

Signed-off-by: Thomas Pedersen <thomas@adapt-ip.com>
Link: https://lore.kernel.org/r/20191119053538.25979-3-thomas@adapt-ip.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-11-22 13:36:25 +01:00
Toke Høiland-Jørgensen
5072f73cb6 mac80211: Add new sta_info getter by sta/vif addrs
In ieee80211_tx_status() we don't have an sdata struct when looking up the
destination sta. Instead, we just do a lookup by the vif addr that is the
source of the packet being completed. Factor this out into a new sta_info
getter helper, since we need to use it for accounting AQL as well.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/r/20191112130835.382062-1-toke@redhat.com
[remove internal rcu_read_lock(), document instead]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-11-22 12:53:53 +01:00
Johannes Berg
b226a826d8 mac80211: add a comment about monitor-to-dev injection
Add a note with a use-case for the monitor-to-dev injection
mechanism in mac80211, reported by Ben Greear.

Change-Id: I6456997ef9bc40b24ede860b6ef2fed5af49cf44
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-11-22 12:42:42 +01:00
David S. Miller
14684b9301 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
One conflict in the BPF samples Makefile, some fixes in 'net' whilst
we were converting over to Makefile.target rules in 'net-next'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-09 11:04:37 -08:00
Geert Uytterhoeven
0628cda318 mac80211: Use debugfs_create_xul() helper
Use the new debugfs_create_xul() helper instead of open-coding the same
operation.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Link: https://lore.kernel.org/r/20191025094130.26033-3-geert+renesas@glider.be
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-09 11:52:56 +01:00
Toke Høiland-Jørgensen
6912daed05 mac80211: Shrink the size of ack_frame_id to make room for tx_time_est
To implement airtime queue limiting, we need to keep a running account of
the estimated airtime of all skbs queued into the device. Do to this
correctly, we need to store the airtime estimate into the skb so we can
decrease the outstanding balance when the skb is freed. This means that the
time estimate must be stored somewhere that will survive for the lifetime
of the skb.

To get this, decrease the size of the ack_frame_id field to 6 bits, and
lower the size of the ID space accordingly. This leaves 10 bits for use for
tx_time_est, which is enough to store a maximum of 4096 us, if we shift the
values so they become units of 4us.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/r/157182474063.150713.16132669599100802716.stgit@toke.dk
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-11-08 10:19:19 +01:00
Johannes Berg
f61d7884ce mac80211: don't re-parse elems in ieee80211_assoc_success()
We've already parsed the same data in the caller, so we can
pass it. The only thing is that we might fill in more details
in ieee80211_assoc_success(), but that doesn't bother the
caller, so it's fine to do even when we share the parsed data.

This reduces the stack space usage of the call stack here,
Arnd reported it had grown above the 1024 byte warning limit.

Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Link: https://lore.kernel.org/r/20191028125240.cb7661671bd2.I757c8752bf4f2f35e54f5e0a2c0a9cd9216c3d8b@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-11-08 10:18:31 +01:00
John Crispin
5d8983c8c3 mac80211: move store skb ack code to its own function
This patch moves the code handling SKBTX_WIFI_STATUS inside the TX path
into an extra function. This allows us to reuse it inside the 802.11 encap
offloading datapath.

Signed-off-by: John Crispin <john@phrozen.org>
Link: https://lore.kernel.org/r/20191029091304.7330-2-john@phrozen.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-11-08 10:18:13 +01:00
Ahmed Zaki
285531f9e6 mac80211: fix station inactive_time shortly after boot
In the first 5 minutes after boot (time of INITIAL_JIFFIES),
ieee80211_sta_last_active() returns zero if last_ack is zero. This
leads to "inactive time" showing jiffies_to_msecs(jiffies).

 # iw wlan0 station get fc:ec:da:64:a6:dd
 Station fc:ec:da:64:a6:dd (on wlan0)
	inactive time:	4294894049 ms
	.
	.
	connected time:	70 seconds

Fix by returning last_rx if last_ack == 0.

Signed-off-by: Ahmed Zaki <anzaki@gmail.com>
Link: https://lore.kernel.org/r/20191031121243.27694-1-anzaki@gmail.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-11-08 09:17:28 +01:00
Johannes Berg
6dd47d9754 mac80211: fix ieee80211_txq_setup_flows() failure path
If ieee80211_txq_setup_flows() fails, we don't clean up LED
state properly, leading to crashes later on, fix that.

Fixes: dc8b274f09 ("mac80211: Move up init of TXQs")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-by: Toke Høiland-Jørgensen <toke@toke.dk>
Link: https://lore.kernel.org/r/20191105154110.1ccf7112ba5d.I0ba865792446d051867b33153be65ce6b063d98c@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-11-08 09:11:33 +01:00
David S. Miller
2f184393e0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Several cases of overlapping changes which were for the most
part trivially resolvable.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-20 10:43:00 -07:00
David S. Miller
7e0d15ee0d A few more small things, nothing really stands out:
* minstrel improvements from Felix
  * a TX aggregation simplification
  * some additional capabilities for hwsim
  * minor cleanups & docs updates
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Merge tag 'mac80211-next-for-net-next-2019-10-11' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next

Johannes Berg says:

====================
A few more small things, nothing really stands out:
 * minstrel improvements from Felix
 * a TX aggregation simplification
 * some additional capabilities for hwsim
 * minor cleanups & docs updates
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-13 11:29:07 -07:00
Felix Fietkau
5f63afe028 mac80211: minstrel_ht: rename prob_ewma to prob_avg, use it for the new average
Reduces per-rate data structure size

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://lore.kernel.org/r/20191008171139.96476-3-nbd@nbd.name
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-10-11 10:31:45 +02:00
Felix Fietkau
b1103d2567 mac80211: minstrel_ht: replace rate stats ewma with a better moving average
Rate success probability usually fluctuates a lot under normal conditions.
With a simple EWMA, noise and fluctuation can be reduced by increasing the
window length, but that comes at the cost of introducing lag on sudden
changes.

This change replaces the EWMA implementation with a moving average that's
designed to significantly reduce lag while keeping a bigger window size
by being better at filtering out noise.

It is only slightly more expensive than the simple EWMA and still avoids
divisions in its calculation.

The algorithm is adapted from an implementation intended for a completely
different field (stock market trading), where the tradeoff of lag vs
noise filtering is equally important. It is based on the "smoothing filter"
from http://www.stockspotter.com/files/PredictiveIndicators.pdf.

I have adapted it to fixed-point math with some constants so that it uses
only addition, bit shifts and multiplication

To better make use of the filtering and bigger window size, the update
interval time is cut in half.

For testing, the algorithm can be reverted to the older one via debugfs

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://lore.kernel.org/r/20191008171139.96476-2-nbd@nbd.name
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-10-11 10:31:32 +02:00
Felix Fietkau
8f2f495ca9 mac80211: minstrel: remove divisions in tx status path
Use a slightly different threshold for downgrading spatial streams to
make it easier to calculate without divisions.
Slightly reduces CPU overhead.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://lore.kernel.org/r/20191008171139.96476-1-nbd@nbd.name
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-10-11 10:31:15 +02:00
Aaron Komisar
dc0c18ed22 mac80211: fix scan when operating on DFS channels in ETSI domains
In non-ETSI regulatory domains scan is blocked when operating channel
is a DFS channel. For ETSI, however, once DFS channel is marked as
available after the CAC, this channel will remain available (for some
time) even after leaving this channel.

Therefore a scan can be done without any impact on the availability
of the DFS channel as no new CAC is required after the scan.

Enable scan in mac80211 in these cases.

Signed-off-by: Aaron Komisar <aaron.komisar@tandemg.com>
Link: https://lore.kernel.org/r/1570024728-17284-1-git-send-email-aaron.komisar@tandemg.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-10-07 22:10:50 +02:00
Johannes Berg
95697f9907 mac80211: accept deauth frames in IBSS mode
We can process deauth frames and all, but we drop them very
early in the RX path today - this could never have worked.

Fixes: 2cc59e784b ("mac80211: reply to AUTH with DEAUTH if sta allocation fails in IBSS")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/20191004123706.15768-2-luca@coelho.fi
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-10-07 21:59:48 +02:00
Will Deacon
4152561f5d mac80211: Reject malformed SSID elements
Although this shouldn't occur in practice, it's a good idea to bounds
check the length field of the SSID element prior to using it for things
like allocations or memcpy operations.

Cc: <stable@vger.kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Reported-by: Nicolas Waisman <nico@semmle.com>
Signed-off-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20191004095132.15777-1-will@kernel.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-10-04 14:01:14 +02:00
Johannes Berg
2ce113de31 mac80211: simplify TX aggregation start
There really is no need to make drivers call the
ieee80211_start_tx_ba_cb_irqsafe() function and then
schedule the worker if all we want is to set a bit.

Add a new return value (that was previously considered
invalid) to indicate that the driver is immediately
ready for the session, and make drivers use it. The
only drivers that remain different are the Intel ones
as they need to negotiate more with the firmware.

Link: https://lore.kernel.org/r/1570007543-I152912660131cbab2e5d80b4218238c20f8a06e5@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-10-04 13:58:13 +02:00
Johannes Berg
4fd0328d2f mac80211: pass internal sta to ieee80211_tx_frags()
This simplifies the code somewhat, and if necessary would let
us access the sta itself in that code.

Link: https://lore.kernel.org/r/1569965193-Id656db92703dded4bb2e3ec5dc329529f58e58f0@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-10-04 13:57:50 +02:00
Koen Vandeputte
020fa0f2f0 mac80211: IBSS: avoid unneeded return value processing
when ieee80211_ibss_csa_beacon() fails, we return it's value.
When it succeeds, we basically copy it's value and also .. return it.

Just return it immediately, simplifying the code.

Signed-off-by: Koen Vandeputte <koen.vandeputte@ncentric.com>
Link: https://lore.kernel.org/r/20190911141431.12498-1-koen.vandeputte@ncentric.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-10-04 13:47:12 +02:00
Johannes Berg
d8dec42b5c mac80211: keep BHs disabled while calling drv_tx_wake_queue()
Drivers typically expect this, as it's the case for almost all cases
where this is called (i.e. from the TX path). Also, the code in mac80211
itself (if the driver calls ieee80211_tx_dequeue()) expects this as it
uses this_cpu_ptr() without additional protection.

This should fix various reports of the problem:
https://bugzilla.kernel.org/show_bug.cgi?id=204127
https://lore.kernel.org/linux-wireless/CAN5HydrWb3o_FE6A1XDnP1E+xS66d5kiEuhHfiGKkLNQokx13Q@mail.gmail.com/
https://lore.kernel.org/lkml/nycvar.YFH.7.76.1909111238470.473@cbobk.fhfr.pm/

Cc: stable@vger.kernel.org
Reported-and-tested-by: Jiri Kosina <jkosina@suse.cz>
Reported-by: Aaron Hill <aa1ronham@gmail.com>
Reported-by: Lukas Redlinger <rel+kernel@agilox.net>
Reported-by: Oleksii Shevchuk <alxchk@gmail.com>
Fixes: 21a5d4c3a4 ("mac80211: add stop/start logic for software TXQs")
Link: https://lore.kernel.org/r/1569928763-I3e8838c5ecad878e59d4a94eb069a90f6641461a@changeid
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-10-01 17:56:19 +02:00
Miaoqing Pan
8ed31a2640 mac80211: fix txq null pointer dereference
If the interface type is P2P_DEVICE or NAN, read the file of
'/sys/kernel/debug/ieee80211/phyx/netdev:wlanx/aqm' will get a
NULL pointer dereference. As for those interface type, the
pointer sdata->vif.txq is NULL.

Unable to handle kernel NULL pointer dereference at virtual address 00000011
CPU: 1 PID: 30936 Comm: cat Not tainted 4.14.104 #1
task: ffffffc0337e4880 task.stack: ffffff800cd20000
PC is at ieee80211_if_fmt_aqm+0x34/0xa0 [mac80211]
LR is at ieee80211_if_fmt_aqm+0x34/0xa0 [mac80211]
[...]
Process cat (pid: 30936, stack limit = 0xffffff800cd20000)
[...]
[<ffffff8000b7cd00>] ieee80211_if_fmt_aqm+0x34/0xa0 [mac80211]
[<ffffff8000b7c414>] ieee80211_if_read+0x60/0xbc [mac80211]
[<ffffff8000b7ccc4>] ieee80211_if_read_aqm+0x28/0x30 [mac80211]
[<ffffff80082eff94>] full_proxy_read+0x2c/0x48
[<ffffff80081eef00>] __vfs_read+0x2c/0xd4
[<ffffff80081ef084>] vfs_read+0x8c/0x108
[<ffffff80081ef494>] SyS_read+0x40/0x7c

Signed-off-by: Miaoqing Pan <miaoqing@codeaurora.org>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/r/1569549796-8223-1-git-send-email-miaoqing@codeaurora.org
[trim useless data from commit message]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-10-01 17:56:19 +02:00
David S. Miller
aa2eaa8c27 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Minor overlapping changes in the btusb and ixgbe drivers.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-15 14:17:27 +02:00
Jouni Malinen
3e493173b7 mac80211: Do not send Layer 2 Update frame before authorization
The Layer 2 Update frame is used to update bridges when a station roams
to another AP even if that STA does not transmit any frames after the
reassociation. This behavior was described in IEEE Std 802.11F-2003 as
something that would happen based on MLME-ASSOCIATE.indication, i.e.,
before completing 4-way handshake. However, this IEEE trial-use
recommended practice document was published before RSN (IEEE Std
802.11i-2004) and as such, did not consider RSN use cases. Furthermore,
IEEE Std 802.11F-2003 was withdrawn in 2006 and as such, has not been
maintained amd should not be used anymore.

Sending out the Layer 2 Update frame immediately after association is
fine for open networks (and also when using SAE, FT protocol, or FILS
authentication when the station is actually authenticated by the time
association completes). However, it is not appropriate for cases where
RSN is used with PSK or EAP authentication since the station is actually
fully authenticated only once the 4-way handshake completes after
authentication and attackers might be able to use the unauthenticated
triggering of Layer 2 Update frame transmission to disrupt bridge
behavior.

Fix this by postponing transmission of the Layer 2 Update frame from
station entry addition to the point when the station entry is marked
authorized. Similarly, send out the VLAN binding update only if the STA
entry has already been authorized.

Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-11 14:59:26 +01:00
David S. Miller
c1b3ddf7c3 We have a number of changes, but things are settling down:
* a fix in the new 6 GHz channel support
  * a fix for recent minstrel (rate control) updates
    for an infinite loop
  * handle interface type changes better wrt. management frame
    registrations (for management frames sent to userspace)
  * add in-BSS RX time to survey information
  * handle HW rfkill properly if !CONFIG_RFKILL
  * send deauth on IBSS station expiry, to avoid state mismatches
  * handle deferred crypto tailroom updates in mac80211 better
    when device restart happens
  * fix a spectre-v1 - really a continuation of a previous patch
  * advertise NL80211_CMD_UPDATE_FT_IES as supported if so
  * add some missing parsing in VHT extended NSS support
  * support HE in mac80211_hwsim
  * let mac80211 drivers determine the max MTU themselves
 along with the usual cleanups etc.
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Merge tag 'mac80211-next-for-davem-2019-09-11' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next

Johannes Berg says:

====================
We have a number of changes, but things are settling down:
 * a fix in the new 6 GHz channel support
 * a fix for recent minstrel (rate control) updates
   for an infinite loop
 * handle interface type changes better wrt. management frame
   registrations (for management frames sent to userspace)
 * add in-BSS RX time to survey information
 * handle HW rfkill properly if !CONFIG_RFKILL
 * send deauth on IBSS station expiry, to avoid state mismatches
 * handle deferred crypto tailroom updates in mac80211 better
   when device restart happens
 * fix a spectre-v1 - really a continuation of a previous patch
 * advertise NL80211_CMD_UPDATE_FT_IES as supported if so
 * add some missing parsing in VHT extended NSS support
 * support HE in mac80211_hwsim
 * let mac80211 drivers determine the max MTU themselves
along with the usual cleanups etc.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-11 14:57:17 +01:00
Wen Gong
06354665f9 mac80211: allow drivers to set max MTU
Make it possibly for drivers to adjust the default max_mtu
by storing it in the hardware struct and using that value
for all interfaces.

Signed-off-by: Wen Gong <wgong@codeaurora.org>
Link: https://lore.kernel.org/r/1567738137-31748-1-git-send-email-wgong@codeaurora.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-09-11 09:33:29 +02:00
Johannes Berg
4b08d1b6a9 mac80211: IBSS: send deauth when expiring inactive STAs
When we expire an inactive station, try to send it a deauth. This
helps if it's actually still around, and just has issues with
beacon distribution (or we do), and it will not also remove us.
Then, if we have shared state, this may not be reset properly,
causing problems; for example, we saw a case where aggregation
sessions weren't removed properly (due to the TX start being
offloaded to firmware and it relying on deauth for stop), causing
a lot of traffic to get lost due to the SN reset after remove/add
of the peer.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/20190830112451.21655-9-luca@coelho.fi
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-09-11 09:33:29 +02:00
Luca Coelho
753a9a729f mac80211: don't check if key is NULL in ieee80211_key_link()
We already assume that key is not NULL and dereference it in a few
other places before we check whether it is NULL, so the check is
unnecessary.  Remove it.

Fixes: 96fc6efb9a ("mac80211: IEEE 802.11 Extended Key ID support")
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/20190830112451.21655-8-luca@coelho.fi
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-09-11 09:33:28 +02:00
Lior Cohen
624ff4b210 mac80211: clear crypto tx tailroom counter upon keys enable
In case we got a fw restart while roaming from encrypted AP to
non-encrypted one, we might end up with hitting a warning on the pending
counter crypto_tx_tailroom_pending_dec having a non-zero value.

The following comment taken from net/mac80211/key.c explains the rational
for the delayed tailroom needed:

	/*
	* The reason for the delayed tailroom needed decrementing is to
	* make roaming faster: during roaming, all keys are first deleted
	* and then new keys are installed. The first new key causes the
	* crypto_tx_tailroom_needed_cnt to go from 0 to 1, which invokes
	* the cost of synchronize_net() (which can be slow). Avoid this
	* by deferring the crypto_tx_tailroom_needed_cnt decrementing on
	* key removal for a while, so if we roam the value is larger than
	* zero and no 0->1 transition happens.
	*
	* The cost is that if the AP switching was from an AP with keys
	* to one without, we still allocate tailroom while it would no
	* longer be needed. However, in the typical (fast) roaming case
	* within an ESS this usually won't happen.
	*/

The next flow lead to the warning eventually reported as a bug:
1. Disconnect from encrypted AP
2. Set crypto_tx_tailroom_pending_dec = 1 for the key
3. Schedule work
4. Reconnect to non-encrypted AP
5. Add a new key, setting the tailroom counter = 1
6. Got FW restart while pending counter is set ---> hit the warning

While on it, the ieee80211_reset_crypto_tx_tailroom() func was merged into
its single caller ieee80211_reenable_keys (previously called
ieee80211_enable_keys). Also, we reset the crypto_tx_tailroom_pending_dec
and remove the counters warning as we just reset both.

Signed-off-by: Lior Cohen <lior2.cohen@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/20190830112451.21655-7-luca@coelho.fi
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-09-11 09:33:28 +02:00
Johannes Berg
1c9559734e mac80211: remove unnecessary key condition
When we reach this point, the key cannot be NULL. Remove the condition
that suggests otherwise.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/20190830112451.21655-6-luca@coelho.fi
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-09-11 09:33:28 +02:00
Johannes Berg
5462632488 mac80211: list features in WEP/TKIP disable in better order
"HE/HT/VHT" is a bit confusing since really the order of
development (and possible support) is different - change
this to "HT/VHT/HE".

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/20190830112451.21655-4-luca@coelho.fi
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-09-11 09:13:42 +02:00
Mordechay Goodstein
e5c0b0fff6 mac80211: vht: add support VHT EXT NSS BW in parsing VHT
This fixes was missed in parsing the vht capabilities max bw
support.

Signed-off-by: Mordechay Goodstein <mordechay.goodstein@intel.com>
Fixes: e80d642552 ("mac80211: copy VHT EXT NSS BW Support/Capable data to station")
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/20190830114057.22197-1-luca@coelho.fi
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-09-11 09:13:03 +02:00
David S. Miller
765b7590c9 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
r8152 conflicts are the NAPI fixes in 'net' overlapping with
some tasklet stuff in net-next

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-02 11:20:17 -07:00
Denis Kenzior
f8b43c5cf4 mac80211: Correctly set noencrypt for PAE frames
The noencrypt flag was intended to be set if the "frame was received
unencrypted" according to include/uapi/linux/nl80211.h.  However, the
current behavior is opposite of this.

Cc: stable@vger.kernel.org
Fixes: 018f6fbf54 ("mac80211: Send control port frames over nl80211")
Signed-off-by: Denis Kenzior <denkenz@gmail.com>
Link: https://lore.kernel.org/r/20190827224120.14545-3-denkenz@gmail.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-08-29 16:40:00 +02:00
Denis Kenzior
c8a41c6afa mac80211: Don't memset RXCB prior to PAE intercept
In ieee80211_deliver_skb_to_local_stack intercepts EAPoL frames if
mac80211 is configured to do so and forwards the contents over nl80211.
During this process some additional data is also forwarded, including
whether the frame was received encrypted or not.  Unfortunately just
prior to the call to ieee80211_deliver_skb_to_local_stack, skb->cb is
cleared, resulting in incorrect data being exposed over nl80211.

Fixes: 018f6fbf54 ("mac80211: Send control port frames over nl80211")
Cc: stable@vger.kernel.org
Signed-off-by: Denis Kenzior <denkenz@gmail.com>
Link: https://lore.kernel.org/r/20190827224120.14545-2-denkenz@gmail.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-08-29 16:38:36 +02:00
David S. Miller
68aaf44595 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Minor conflict in r8169, bug fix had two versions in net
and net-next, take the net-next hunks.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-27 14:23:31 -07:00
Colin Ian King
b26af93044 mac80211: minstrel_ht: fix infinite loop because supported is not being shifted
Currently the for-loop will spin forever if variable supported is
non-zero because supported is never changed.  Fix this by adding in
the missing right shift of supported.

Addresses-Coverity: ("Infinite loop")
Fixes: 48cb39522a ("mac80211: minstrel_ht: improve rate probing for devices with static fallback")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: https://lore.kernel.org/r/20190822122034.28664-1-colin.king@canonical.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-08-22 21:58:18 +02:00
Felix Fietkau
48cb39522a mac80211: minstrel_ht: improve rate probing for devices with static fallback
On some devices that only support static rate fallback tables sending rate
control probing packets can be really expensive.
Probing lower rates can already hurt throughput quite a bit. What hurts even
more is the fact that on mt76x0/mt76x2, single probing packets can only be
forced by directing packets at a different internal hardware queue, which
causes some heavy reordering and extra latency.
The reordering issue is mainly problematic while pushing lots of packets to
a particular station. If there is little activity, the overhead of probing is
neglegible.

The static fallback behavior is designed to pretty much only handle rate
control algorithms that use only a very limited set of rates on which the
algorithm switches up/down based on packet error rate.

In order to better support that kind of hardware, this patch implements a
different approach to rate probing where it switches to a slightly higher rate,
waits for tx status feedback, then updates the stats and switches back to
the new max throughput rate. This only triggers above a packet rate of 100
per stats interval (~50ms).
For that kind of probing, the code has to reduce the set of probing rates
a lot more compared to single packet probing, so it uses only one packet
per MCS group which is either slightly faster, or as close as possible to
the max throughput rate.
This allows switching between similar rates with different numbers of
streams. The algorithm assumes that the hardware will work its way lower
within an MCS group in case of retransmissions, so that lower rates don't
have to be probed by the high packets per second rate probing code.

To further reduce the search space, it also does not probe rates with lower
channel bandwidth than the max throughput rate.

At the moment, these changes will only affect mt76x0/mt76x2.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://lore.kernel.org/r/20190820095449.45255-4-nbd@nbd.name
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-08-21 11:10:13 +02:00