A common pattern with skb_put() is to just want to memcpy()
some data into the new space, introduce skb_put_data() for
this.
An spatch similar to the one for skb_put_zero() converts many
of the places using it:
@@
identifier p, p2;
expression len, skb, data;
type t, t2;
@@
(
-p = skb_put(skb, len);
+p = skb_put_data(skb, data, len);
|
-p = (t)skb_put(skb, len);
+p = skb_put_data(skb, data, len);
)
(
p2 = (t2)p;
-memcpy(p2, data, len);
|
-memcpy(p, data, len);
)
@@
type t, t2;
identifier p, p2;
expression skb, data;
@@
t *p;
...
(
-p = skb_put(skb, sizeof(t));
+p = skb_put_data(skb, data, sizeof(t));
|
-p = (t *)skb_put(skb, sizeof(t));
+p = skb_put_data(skb, data, sizeof(t));
)
(
p2 = (t2)p;
-memcpy(p2, data, sizeof(*p));
|
-memcpy(p, data, sizeof(*p));
)
@@
expression skb, len, data;
@@
-memcpy(skb_put(skb, len), data, len);
+skb_put_data(skb, data, len);
(again, manually post-processed to retain some comments)
Reviewed-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There were many places that my previous spatch didn't find,
as pointed out by yuan linyu in various patches.
The following spatch found many more and also removes the
now unnecessary casts:
@@
identifier p, p2;
expression len;
expression skb;
type t, t2;
@@
(
-p = skb_put(skb, len);
+p = skb_put_zero(skb, len);
|
-p = (t)skb_put(skb, len);
+p = skb_put_zero(skb, len);
)
... when != p
(
p2 = (t2)p;
-memset(p2, 0, len);
|
-memset(p, 0, len);
)
@@
type t, t2;
identifier p, p2;
expression skb;
@@
t *p;
...
(
-p = skb_put(skb, sizeof(t));
+p = skb_put_zero(skb, sizeof(t));
|
-p = (t *)skb_put(skb, sizeof(t));
+p = skb_put_zero(skb, sizeof(t));
)
... when != p
(
p2 = (t2)p;
-memset(p2, 0, sizeof(*p));
|
-memset(p, 0, sizeof(*p));
)
@@
expression skb, len;
@@
-memset(skb_put(skb, len), 0, len);
+skb_put_zero(skb, len);
Apply it to the tree (with one manual fixup to keep the
comment in vxlan.c, which spatch removed.)
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When mac80211 changes the channel, it also calls into the driver's
bss_info_changed() callback, e.g. with BSS_CHANGED_IDLE. The driver
may, like iwlwifi does, access more data from bss_info in that case
and iwlwifi accesses the basic_rates bitmap, but if changing from a
band with more (basic) rates to one with fewer, an out-of-bounds
access of the rate array may result.
While we can't avoid having invalid data at some point in time, we
can avoid having it while we call the driver - so set up all the
data before configuring the channel, and then apply it afterwards.
This fixes https://bugzilla.kernel.org/show_bug.cgi?id=195677
Reported-by: Johannes Hirte <johannes.hirte@datenkhaos.de>
Tested-by: Johannes Hirte <johannes.hirte@datenkhaos.de>
Debugged-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
There's no need for the station MLME code to handle bitrates for 5
or 10 MHz channels when it can't ever create such a configuration.
Remove the unnecessary code.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Clear the csa_ie in ieee80211_parse_ch_switch_ie() where the data
is filled in, rather than in each caller.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
If ieee80211_hw_restart() is called during authentication, the
authentication process will continue, causing the driver to be called
in a wrong state. This ultimately causes an oops in the iwlwifi
driver (at least).
This fixes bugzilla 195299 partly.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=195299
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Parse the BSS max idle period element and set the BSS configuration
accordingly so the driver can use this information to configure the
max idle period and to use protected management frames for keep alive
when required.
The BSS max idle period element is defined in IEEE802.11-2016,
section 9.4.2.79
Signed-off-by: Avraham Stern <avraham.stern@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Existing API 'ieee80211_get_sdata_band' returns default 2 GHz band even
if the channel context configuration is NULL. This crashes for chipsets
which support 5 Ghz alone when it tries to access members of 'sband'.
Channel context configuration can be NULL in multivif case and when
channel switch is in progress (or) when it fails. Fix this by replacing
the API 'ieee80211_get_sdata_band' with 'ieee80211_get_sband' which
returns a NULL pointer for sband when the channel configuration is NULL.
An example scenario is as below:
In multivif mode (AP + STA) with drivers like ath10k, when we do a
channel switch in the AP vif (which has a number of clients connected)
and a STA vif which is connected to some other AP, when the channel
switch in AP vif fails, while the STA vifs tries to connect to the
other AP, there is a window where the channel context is NULL/invalid
and this results in a crash while the clients connected to the AP vif
tries to reconnect and this race is very similar to the one investigated
by Michal in https://patchwork.kernel.org/patch/3788161/ and this does
happens with hardware that supports 5Ghz alone after long hours of
testing with continuous channel switch on the AP vif
ieee80211 phy0: channel context reservation cannot be finalized because
some interfaces aren't switching
wlan0: failed to finalize CSA, disconnecting
wlan0-1: deauthenticating from 8c:fd:f0:01:54:9c by local choice
(Reason: 3=DEAUTH_LEAVING)
WARNING: CPU: 1 PID: 19032 at net/mac80211/ieee80211_i.h:1013 sta_info_alloc+0x374/0x3fc [mac80211]
[<bf77272c>] (sta_info_alloc [mac80211])
[<bf78776c>] (ieee80211_add_station [mac80211]))
[<bf73cc50>] (nl80211_new_station [cfg80211])
Unable to handle kernel NULL pointer dereference at virtual
address 00000014
pgd = d5f4c000
Internal error: Oops: 17 [#1] PREEMPT SMP ARM
PC is at sta_info_alloc+0x380/0x3fc [mac80211]
LR is at sta_info_alloc+0x37c/0x3fc [mac80211]
[<bf772738>] (sta_info_alloc [mac80211])
[<bf78776c>] (ieee80211_add_station [mac80211])
[<bf73cc50>] (nl80211_new_station [cfg80211]))
Cc: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Mohammed Shafi Shajakhan <mohammed@qti.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
If the user rate mask results in no (basic) rates being usable,
clear it. Also, if we're already operating when it's set, reject
it instead.
Technically, selecting basic rates as the criterion is a bit too
restrictive, but calculating the usable rates over all stations
(e.g. in AP mode) is harder, and all stations must support the
basic rates. Similarly, in client mode, the basic rates will be
used anyway for control frames.
This fixes the "no supported rates (...) in rate_mask ..." warning
that occurs on TX when you've selected a rate mask that's not
compatible with the connection (e.g. an AP that enables only the
rates 36, 48, 54 and you've selected only 6, 9, 12.)
Reported-by: Kirtika Ruchandani <kirtika@google.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
There isn't really much harm in not ignoring, since it doesn't
represent a valid rate, but since we already ignore the HT one
also ignore VHT. Also simplify the code a bit.
Fix a typo in the related comment (pointed out by Arend) while
at it.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When disassociation happens only numeric reason is printed
in ieee80211_rx_mgmt_disassoc(). Add text variant, too.
Signed-off-by: Arkadiusz Miśkiewicz <arekm@maven.pl>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Support .set_cqm_rssi_range_config if the beacons are available for
processing in mac80211. There's no reason that this couldn't be
offloaded by mac80211-based drivers but there's no driver method for
that added in this patch.
Signed-off-by: Andrew Zaborowski <andrew.zaborowski@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Update the drivers to pass the RSSI level as a cfg80211_cqm_rssi_notify
parameter and pass this value to userspace in a new nl80211 attribute.
This helps both userspace and also helps in the implementation of the
multiple RSSI thresholds CQM mechanism.
Note for marvell/mwifiex I pass 0 for the RSSI value because the new
RSSI value is not available to the driver at the time of the
cfg80211_cqm_rssi_notify call, but the driver queries the new value
immediately after that, so it is actually available just a moment later
if we wanted to defer caling cfg80211_cqm_rssi_notify until that moment.
Without this, the new cfg80211 code (patch 3) will call .get_station
which will send a duplicate HostCmd_CMD_RSSI_INFO command to the hardware.
Signed-off-by: Andrew Zaborowski <andrew.zaborowski@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Extend ieee80211_cqm_rssi_notify with a rssi_level parameter so that
this information can be passed to netlink clients in the next patch, if
available. Most drivers will have this value at hand. wl1251 receives
events from the firmware that only tell it whether latest measurement
is above or below threshold so we don't pass any value at this time
(parameter is 0).
Signed-off-by: Andrew Zaborowski <andrew.zaborowski@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Commit 4a733ef1be (mac80211: remove PM-QoS listener) removed all use
of 'beaconint_us' from ieee80211_recalc_ps() but left the variable
intact. Compiling with W=1 gives the following warning, fix it.
net/mac80211/mlme.c: In function ‘ieee80211_recalc_ps’:
net/mac80211/mlme.c:1481:7: warning: variable ‘beaconint_us’ set but not used [-Wunused-but-set-variable]
iee80211_tu_to_usec has no side-effects and is safe to remove.
Fixes: 4a733ef1be ("mac80211: remove PM-QoS listener")
Cc: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Kirtika Ruchandani <kirtika@chromium.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When mac80211 abandons an association attempt, it may free
all the data structures, but inform cfg80211 and userspace
about it only by sending the deauth frame it received, in
which case cfg80211 has no link to the BSS struct that was
used and will not cfg80211_unhold_bss() it.
Fix this by providing a way to inform cfg80211 of this with
the BSS entry passed, so that it can clean up properly, and
use this ability in the appropriate places in mac80211.
This isn't ideal: some code is more or less duplicated and
tracing is missing. However, it's a fairly small change and
it's thus easier to backport - cleanups can come later.
Cc: stable@vger.kernel.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This adds support for encrypting (Re)Association Request frame and
decryption (Re)Association Response frame when using FILS in station
mode.
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The special SAE case should be limited only for SAE since the more
generic AUTH_DATA can now be used with other authentication algorithms
as well.
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This adds defines and nl80211 extensions to allow FILS Authentication to
be implemented similarly to SAE. FILS does not need the special rules
for the Authentication transaction number and Status code fields, but it
does need to add non-IE fields. The previously used
NL80211_ATTR_SAE_DATA can be reused for this to avoid having to
duplicate that implementation. Rename that attribute to more generic
NL80211_ATTR_AUTH_DATA (with backwards compatibility define for
NL80211_SAE_DATA).
Also document the special rules related to the Authentication
transaction number and Status code fiels.
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The uapsd_queue field is in QoS IE order and not in
IEEE80211_AC_*'s order.
This means that mac80211 would get confused between
BK and BE which is certainly not such a big deal but
needs to be fixed.
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
In the unlikely situation that the supplicant has negotiated
admission for the background AC (which it has no reason to as
it's not supposed to be requiring admission control to start
with, and we'd ignore such a requirement anyway), the loop
here may terminate with non_acm_ac == 4, which leads to an
array overrun.
Check this explicitly just for completeness.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
In some cases, after a sudden AP disappearing and reconnection to
another AP in the same ESS, user space gets the old AP in scan
results (cached). User space may decide to roam to that old AP
which will cause a disconnection and longer recovery.
Remove APs that are probably out of range from BSS table.
Signed-off-by: David Spinadel <david.spinadel@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This enum is already perfectly aliased to enum nl80211_band, and
the only reason for it is that we get IEEE80211_NUM_BANDS out of
it. There's no really good reason to not declare the number of
bands in nl80211 though, so do that and remove the cfg80211 one.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The regular RX path has a lot of code, but with a few
assumptions on the hardware it's possible to reduce the
amount of code significantly. Currently the assumptions
on the driver are the following:
* hardware/driver reordering buffer (if supporting aggregation)
* hardware/driver decryption & PN checking (if using encryption)
* hardware/driver did de-duplication
* hardware/driver did A-MSDU deaggregation
* AP_LINK_PS is used (in AP mode)
* no client powersave handling in mac80211 (in client mode)
of which some are actually checked per packet:
* de-duplication
* PN checking
* decryption
and additionally packets must
* not be A-MSDU (have been deaggregated by driver/device)
* be data packets
* not be fragmented
* be unicast
* have RFC 1042 header
Additionally dynamically we assume:
* no encryption or CCMP/GCMP, TKIP/WEP/other not allowed
* station must be authorized
* 4-addr format not enabled
Some data needed for the RX path is cached in a new per-station
"fast_rx" structure, so that we only need to look at this and
the packet, no other memory when processing packets on the fast
RX path.
After doing the above per-packet checks, the data path collapses
down to a pretty simple conversion function taking advantage of
the data cached in the small fast_rx struct.
This should speed up the RX processing, and will make it easier
to reason about parallelizing RX (for which statistics will need
to be per-CPU still.)
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
In the likely case that probe_count is 0, don't write to the
memory there.
Also use ifmgd consistently in the function, instead of using
sdata->u.mgd as well.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Drivers may need to track which vif is using VHT MU-MIMO.
Move the flag indicationg the ownership of MU_MIMO to
ieee80211_vif.
Signed-off-by: Sara Sharon <sara.sharon@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Make sure there's at least a debug message whenever the
connection to the AP is terminated.
Also change one message from wiphy_debug() to the common
mlme_dbg().
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The station MLME and IBSS/mesh ones use entirely different
code for interpreting HT and VHT operation elements. Change
the code that interprets them a bit - it now modifies an
existing chandef - and use it also in the MLME code.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
During a sw scan ieee80211_iface_work ignores work items for all vifs.
However after the scan complete work is requeued only for STA, ADHOC
and MESH iftypes.
This occasionally results in event processing getting delayed/not
processed for iftype AP when it coexists with a STA. This can result
in data halt and eventually disconnection on the AP interface.
Cc: stable@vger.kernel.org
Signed-off-by: Sachin Kulkarni <Sachin.Kulkarni@imgtec.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Use to_delayed_work() instead of open-coding it.
Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The Group ID Management frame is an Action frame of
category VHT. It is transmitted by the AP to assign
or change the user position of a STA for one or more
group IDs.
Process and save the group membership data. Notify
underlying driver of changes.
Signed-off-by: Sara Sharon <sara.sharon@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Conflicts:
drivers/net/geneve.c
Here we had an overlapping change, where in 'net' the extraneous stats
bump was being removed whilst in 'net-next' the final argument to
udp_tunnel6_xmit_skb() was being changed.
Signed-off-by: David S. Miller <davem@davemloft.net>
An AP can send an operating channel width change in a beacon
opmode notification IE as long as there's a change in the nss as
well (See 802.11ac-2013 section 10.41).
So don't limit updating to nss only from an opmode notification IE.
Signed-off-by: Eyal Shapira <eyalx.shapira@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When the AP is advertising limited TX power, the message can be
printed over and over again. Suppress it when the power level
isn't changing.
This fixes https://bugzilla.kernel.org/show_bug.cgi?id=106011
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Add new VIF flag, that will allow get NOA update
notification when driver will request this, even
this is not pure P2P vif (eg. STA vif).
Signed-off-by: Janusz Dziedzic <janusz.dziedzic@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
As WMM is required for HT/VHT operation, treat bad WMM parameters
more gracefully by falling back to default parameters instead of
not using WMM assocation. This makes it possible to still use HT
or VHT, although potentially with reduced quality of service due
to unintended WMM parameters.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Disabling WMM has a huge impact these days. It implies that
HT and VHT will be disabled which means that the throughput
will be drammatically reduced.
Since the AIFSN is a transmission parameter, we can play a
bit and fix it up to make it compliant with the 802.11
specification which requires it to be at least 2.
Increasing it from 1 to 2 will slightly reduce the
likelyhood to get a transmission opportunity compared to
other clients that would accept to set AIFSN=1, but at
least it will allow HT and VHT which is a huge gain.
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The function currently determines this value, for use in bss_info.qos,
based on the interface type itself. Make it a parameter instead and
set it with the same logic for now.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Local request to deauthenticate wasn't handled while associating, thus
the association could continue even when the user space required to
disconnect.
Cc: stable@vger.kernel.org
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
There's little point in keeping (and even sending to userspace)
the beacon_loss_count value per station, since it can only apply
to the AP on a managed-mode connection. Move the value to ifmgd,
advertise it only in managed mode, and remove it from ethtool as
it's available through better interfaces.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
As this API has never really seen any use and most drivers don't
ever use the value derived from it, remove it.
Change the only driver using it (rt2x00) to simply use the DTIM
period instead of the "max sleep" time.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This reverts commit 5c48f12017.
Some device drivers (ath10k) offload part of aggregation including AddBA/DelBA
negotiations to firmware. In such scenario, the PMF configuration of
the station needs to be provided to driver to enable encryption of
AddBA/DelBA action frames.
Signed-off-by: Tamizh chelvam <c_traja@qti.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
* many internal fixes, API improvements, cleanups, etc.
* full AP client state tracking in cfg80211/mac80211 from Ayala
* VHT support (in mac80211) for mesh
* some A-MSDU in A-MPDU support from Emmanuel
* show current TX power to userspace (from Rafał)
* support for netlink dump in vendor commands (myself)
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Merge tag 'mac80211-next-for-davem-2015-10-05' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next
Johannes Berg says:
====================
For the current cycle, we have the following right now:
* many internal fixes, API improvements, cleanups, etc.
* full AP client state tracking in cfg80211/mac80211 from Ayala
* VHT support (in mac80211) for mesh
* some A-MSDU in A-MPDU support from Emmanuel
* show current TX power to userspace (from Rafał)
* support for netlink dump in vendor commands (myself)
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead of int with 0/1, use bool with false/true for the
powersave argument to ieee80211_send_nullfunc().
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Instead of nesting two if statements, inline the second
check into the first if statement and to indentation.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
It doesn't seem problematic to change the weight for the average
beacon signal from 3 to 4, so use DECLARE_EWMA. This also makes
the code easier to maintain since bugs like the one fixed in the
previous patch can't happen as easily.
With a fix from Avraham Stern to invert the sign since EMWA uses
unsigned values only.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
yuan linyu