linux.git/net/wireless/scan.c, branch v4.13

cfg80211: make cfg80211_sched_scan_results() work from atomic context

2017-05-23T12:36:46+00:00

Drivers should be able to call cfg80211_sched_scan_results() from atomic
context. However, with the introduction of multiple scheduled scan feature
this requirement was not taken into account resulting in regression shown
below.

[  119.021594] BUG: scheduling while atomic: irq/47-iwlwifi/517/0x00000200
[  119.021604] Modules linked in: [...]
[  119.021759] CPU: 1 PID: 517 Comm: irq/47-iwlwifi Not tainted 4.12.0-rc2-t440s-20170522+ #1
[  119.021763] Hardware name: LENOVO 20AQS03H00/20AQS03H00, BIOS GJET91WW (2.41 ) 09/21/2016
[  119.021766] Call Trace:
[  119.021778]  ? dump_stack+0x5c/0x84
[  119.021784]  ? __schedule_bug+0x4c/0x70
[  119.021792]  ? __schedule+0x496/0x5c0
[  119.021798]  ? schedule+0x2d/0x80
[  119.021804]  ? schedule_preempt_disabled+0x5/0x10
[  119.021810]  ? __mutex_lock.isra.0+0x18e/0x4c0
[  119.021817]  ? __wake_up+0x2f/0x50
[  119.021833]  ? cfg80211_sched_scan_results+0x19/0x60 [cfg80211]
[  119.021844]  ? cfg80211_sched_scan_results+0x19/0x60 [cfg80211]
[  119.021859]  ? iwl_mvm_rx_lmac_scan_iter_complete_notif+0x17/0x30 [iwlmvm]
[  119.021869]  ? iwl_pcie_rx_handle+0x2a9/0x7e0 [iwlwifi]
[  119.021878]  ? iwl_pcie_irq_handler+0x17c/0x730 [iwlwifi]
[  119.021884]  ? irq_forced_thread_fn+0x60/0x60
[  119.021887]  ? irq_thread_fn+0x16/0x40
[  119.021892]  ? irq_thread+0x109/0x180
[  119.021896]  ? wake_threads_waitq+0x30/0x30
[  119.021901]  ? kthread+0xf2/0x130
[  119.021905]  ? irq_thread_dtor+0x90/0x90
[  119.021910]  ? kthread_create_on_node+0x40/0x40
[  119.021915]  ? ret_from_fork+0x26/0x40

Fixes: b34939b98369 ("cfg80211: add request id to cfg80211_sched_scan_*() api")
Reported-by: Sander Eikelenboom 
Signed-off-by: Arend van Spriel 
Signed-off-by: Johannes Berg

cfg80211: add request id to cfg80211_sched_scan_*() api

2017-04-28T12:51:43+00:00

Have proper request id filled in the SCHED_SCAN_RESULTS and
SCHED_SCAN_STOPPED notifications toward user-space by having the
driver provide it through the api.

Reviewed-by: Hante Meuleman 
Reviewed-by: Pieter-Paul Giesberts 
Reviewed-by: Franky Lin 
Signed-off-by: Arend van Spriel 
Signed-off-by: Johannes Berg

cfg80211: add request id parameter to .sched_scan_stop() signature

2017-04-26T21:17:40+00:00

For multiple scheduled scan support the driver needs to know which
scheduled scan request is being stopped. Pass the request id in the
.sched_scan_stop() callback.

Reviewed-by: Hante Meuleman 
Reviewed-by: Pieter-Paul Giesberts 
Reviewed-by: Franky Lin 
Signed-off-by: Arend van Spriel 
Signed-off-by: Johannes Berg

nl80211: allow multiple active scheduled scan requests

2017-04-26T21:17:38+00:00

This patch implements the idea to have multiple scheduled scan requests
running concurrently. It mainly illustrates how to deal with the incoming
request from user-space in terms of backward compatibility. In order to
use multiple scheduled scans user-space needs to provide a flag attribute
NL80211_ATTR_SCHED_SCAN_MULTI to indicate support. If not the request is
treated as a legacy scan.

Drivers currently supporting scheduled scan are now indicating they support
a single scheduled scan request. This obsoletes WIPHY_FLAG_SUPPORTS_SCHED_SCAN.

Reviewed-by: Hante Meuleman 
Reviewed-by: Pieter-Paul Giesberts 
Reviewed-by: Franky Lin 
Signed-off-by: Arend van Spriel 
[clean up netlink destroy path to avoid allocations, code cleanups]
Signed-off-by: Johannes Berg

nl80211: add request id in scheduled scan event messages

2017-04-18T08:23:50+00:00

For multi-scheduled scan support in subsequent patch a request id
will be added. This patch add this request id to the scheduled
scan event messages. For now the request id will always be zero.
With multi-scheduled scan its value will inform user-space to which
scan the event relates.

Reviewed-by: Hante Meuleman 
Reviewed-by: Pieter-Paul Giesberts 
Reviewed-by: Franky Lin 
Signed-off-by: Arend van Spriel 
Signed-off-by: Johannes Berg

nl80211: rework {sched_,}scan event related functions

2016-12-16T12:32:31+00:00

A couple of functions used with scan events were named with
term "send" although they were only preparing the the event
message so renamed those.

Also remove nl80211_send_sched_scan_results() in favor of
just calling nl80211_send_sched_scan() with the right value.

Signed-off-by: Arend van Spriel 
[mention nl80211_send_sched_scan_results() in the commit log]
Signed-off-by: Johannes Berg

cfg80211: limit scan results cache size

2016-11-18T07:44:44+00:00

It's possible to make scanning consume almost arbitrary amounts
of memory, e.g. by sending beacon frames with random BSSIDs at
high rates while somebody is scanning.

Limit the number of BSS table entries we're willing to cache to
1000, limiting maximum memory usage to maybe 4-5MB, but lower
in practice - that would be the case for having both full-sized
beacon and probe response frames for each entry; this seems not
possible in practice, so a limit of 1000 entries will likely be
closer to 0.5 MB.

Cc: stable@vger.kernel.org
Signed-off-by: Johannes Berg

cfg80211: add helper to find an IE that matches a byte-array

2016-09-16T12:49:52+00:00

There are a few places where an IE that matches not only the EID, but
also other bytes inside the element, needs to be found.  To simplify
that and reduce the amount of similar code, implement a new helper
function to match the EID and an extra array of bytes.

Additionally, simplify cfg80211_find_vendor_ie() by using the new
match function.

Signed-off-by: Luca Coelho 
Signed-off-by: Johannes Berg

nl80211: support beacon report scanning

2016-07-06T12:51:31+00:00

Beacon report radio measurement requires reporting observed BSSs
on the channels specified in the beacon request. If the measurement
mode is set to passive or active, it requires actually performing a
scan (passive or active, accordingly), and reporting the time that
the scan was started and the time each beacon/probe was received
(both in terms of TSF of the BSS of the requesting AP). If the
request mode is table, this information is optional.
In addition, the radio measurement request specifies the channel
dwell time for the measurement.

In order to use scan for beacon report when the mode is active or
passive, add a parameter to scan request that specifies the
channel dwell time, and add scan start time and beacon received time
to scan results information.

Supporting beacon report is required for Multi Band Operation (MBO).

Signed-off-by: Assaf Krauss 
Signed-off-by: David Spinadel 
Signed-off-by: Avraham Stern 
Signed-off-by: Luca Coelho 
Signed-off-by: Johannes Berg

cfg80211: allow finding vendor with OUI without specifying the OUI type

2016-05-12T09:15:42+00:00

This allows finding vendor IE from a specific vendor.

Signed-off-by: Emmanuel Grumbach 
Signed-off-by: Luca Coelho 
Signed-off-by: Johannes Berg