___cfg80211_scan_done() can be called in some cases
(e.g. on NETDEV_DOWN) before the low level driver
notified scan completion (which is indicated by
passing leak=true).

Clearing rdev->scan_req in this case is buggy, as
scan_done_wk might have already being queued/running
(and can't be flushed as it takes rtnl()).

If a new scan will be requested at this stage, the
scan_done_wk will try freeing it (instead of the
previous scan), and this will later result in
a use after free.

Simply remove the "leak" option, and replace it with
a standard WARN_ON.

An example backtrace after such crash:
Unable to handle kernel paging request at virtual address fffffee5
pgd = c0004000
[fffffee5] *pgd=9fdf6821, *pte=00000000, *ppte=00000000
Internal error: Oops: 17 [#1] SMP ARM
PC is at cfg80211_scan_done+0x28/0xc4 [cfg80211]
LR is at __ieee80211_scan_completed+0xe4/0x2dc [mac80211]
[<bf0077b0>] (cfg80211_scan_done+0x28/0xc4 [cfg80211])
[<bf0973d4>] (__ieee80211_scan_completed+0xe4/0x2dc [mac80211])
[<bf0982cc>] (ieee80211_scan_work+0x94/0x4f0 [mac80211])
[<c005fd10>] (process_one_work+0x1b0/0x4a8)
[<c0060404>] (worker_thread+0x138/0x37c)
[<c0066d70>] (kthread+0xa4/0xb0)
Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

On scan completion we try start any pending roc.

However, if scan was just pending (and not actually started)
there is no point in trying to start the roc, as it might
have started already.

This solves the following warning:
WARNING: CPU: 0 PID: 3552 at net/mac80211/offchannel.c:269 ieee80211_start_next_roc+0x164/0x204 [mac80211]()
[<c001cd38>] (unwind_backtrace+0x0/0xf0)
[<c00181d0>] (show_stack+0x10/0x14)
[<c05c0d8c>] (dump_stack+0x78/0x94)
[<c0047c08>] (warn_slowpath_common+0x68/0x8c)
[<c0047c48>] (warn_slowpath_null+0x1c/0x24)
[<bf4d6660>] (ieee80211_start_next_roc+0x164/0x204 [mac80211])
[<bf4d5a74>] (ieee80211_scan_cancel+0xe8/0x190 [mac80211])
[<bf4df970>] (ieee80211_do_stop+0x63c/0x79c [mac80211])
[<bf4dfae0>] (ieee80211_stop+0x10/0x18 [mac80211])
[<c0504d84>] (__dev_close_many+0x84/0xcc)
[<c0504df4>] (__dev_close+0x28/0x3c)
[<c0509708>] (__dev_change_flags+0x78/0x144)
[<c0509854>] (dev_change_flags+0x10/0x48)
[<c055fe3c>] (devinet_ioctl+0x614/0x6d0)
[<c04f22a0>] (sock_ioctl+0x5c/0x2a4)
[<c0124eb4>] (do_vfs_ioctl+0x7c/0x5d8)
[<c012547c>] (SyS_ioctl+0x6c/0x7c)
Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

In some cases, determining the completed scan type was
done by testing the SCAN_HW_SCANNING flag.

However, this doesn't take care for the case in which
the hw scan was requested, but hasn't started yet (e.g.
due to active remain_on_channel).

Replace this test by checking whether ops->hw_scan is
defined.

This solves the following warning:

WARNING: CPU: 0 PID: 3552 at net/mac80211/offchannel.c:156 __ieee80211_scan_completed+0x1b4/0x2dc [mac80211]()
[<c001cd38>] (unwind_backtrace+0x0/0xf0)
[<c00181d0>] (show_stack+0x10/0x14)
[<c05c0d8c>] (dump_stack+0x78/0x94)
[<c0047c08>] (warn_slowpath_common+0x68/0x8c)
[<c0047c48>] (warn_slowpath_null+0x1c/0x24)
[<bf4d4504>] (__ieee80211_scan_completed+0x1b4/0x2dc [mac80211])
[<bf4d5a74>] (ieee80211_scan_cancel+0xe8/0x190 [mac80211])
[<bf4df970>] (ieee80211_do_stop+0x63c/0x79c [mac80211])
[<bf4dfae0>] (ieee80211_stop+0x10/0x18 [mac80211])
[<c0504d84>] (__dev_close_many+0x84/0xcc)
[<c0504df4>] (__dev_close+0x28/0x3c)
[<c0509708>] (__dev_change_flags+0x78/0x144)
[<c0509854>] (dev_change_flags+0x10/0x48)
[<c055fe3c>] (devinet_ioctl+0x614/0x6d0)
[<c04f22a0>] (sock_ioctl+0x5c/0x2a4)
[<c0124eb4>] (do_vfs_ioctl+0x7c/0x5d8)
[<c012547c>] (SyS_ioctl+0x6c/0x7c)
Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

cfg80211_leave stops sched scan when any station vif
is leaving. Add an explicit check and call it only
when the relevant vif (the one we scan on) is leaving.
Signed-off-by: Barak Bercovitz <barak@wizery.com>
[Eliad - changed the commit message a bit]
Signed-off-by: Eliad Peller <eliad@wizery.com>
[Johannes - add ASSERT_RTNL since that protects the pointer]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Rename NL80211_TXRATE_MCS to NL80211_TXRATE_HT and also
rename mcs to ht_mcs in struct cfg80211_bitrate_mask.
Signed-off-by: Janusz Dziedzic <janusz.dziedzic@tieto.com>
[reword commit message]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Allow setting the bitrate masks back to default by
omitting the NL80211_ATTR_TX_RATES attribute.
Signed-off-by: Janusz Dziedzic <janusz.dziedzic@tieto.com>
[rephrase commit message]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

This shouldn't be happening, so warn if it does, since we'd
then leak a station entry.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Remove the unnecessary duplicate test of "if (skb) {"
when !CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS.

Remove now unnecessary __maybe_unused, neaten comment
Remove unnecessary parenthesis around align cast.
Substitute reference to deprecated compare_ether_addr
with ether_addr_equal (in the comment.)
Signed-off-by: Joe Perches <joe@perches.com>
[edit commit log slightly]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

This permits the use of DFS channel once the CAC is conducted and
no radar is detected.
Signed-off-by: Chun-Yeow Yeoh <yeohchunyeow@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Add support for vendor-specific commands to nl80211. This is
intended to be used for really vendor-specific functionality
that can't be implemented in a generic fashion for any reason.
It's *NOT* intended to be used for any normal/generic feature
or any optimisations that could be implemented across drivers.

Currently, only vendor commands (with replies) are supported,
no dump operations or vendor-specific notifications.

Also add a function wdev_to_ieee80211_vif() to mac80211 which
is needed for mac80211-based drivers wanting to implement any
vendor commands.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Don't clear cfg80211_bitrate_mask twice in
nl80211_set_tx_bitrate_mask() function.
Signed-off-by: Janusz Dziedzic <janusz.dziedzic@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

The same code appears just a few lines below.
Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Check the DFS region before channel availability check.
Signed-off-by: Luis R. Rodriguez <mcgrof@do-not-panic.com>
Signed-off-by: Janusz Dziedzic <janusz.dziedzic@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

This can be used outside of the regulatory context for any checks
on the DFS region. The central cfg80211 dfs_region is always used
and if it does not match with the wiphy a debug print is issued.
Signed-off-by: Luis R. Rodriguez <mcgrof@do-not-panic.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

This attribute is needed for setting Operating Mode Notification
in AP mode from User Space. This functionality is required when
User Space received Assoc Request contains Operation Mode
Notification element.
Signed-off-by: Marek Kwaczynski <marek.kwaczynski@tieto.com>
[fix typos, nl80211 documentation]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

There's no reason for the variable to not be inside
the #ifdef, move it.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

This reverts commit 488b366a.

The code isn't used by anyone, and the Intel driver isn't planning
to use it either right now.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Drivers with hardware rate control were given
sta->rx_nss set to 0. This was because rx_nss
calculation procedure was protected by hw/sw rate
control check.
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

The current channel switch code has a potential deadlock:
1) * cfg80211_stop_ap acquires wdev-lock
   * ieee80211_stop_ap calls cancel_work_sync for the csa_finalize_work,
     which acquires the associated worker-lock
2) * ieee80211_csa_finalize_work holds the worker-lock when run
   * it calls cfg80211_ch_switch_notify which will claim the wdev-lock,
     and also needs to claim the sdata-lock (which is the same as the
     wdev-lock) to modify the beacons.

It is sufficient to just set the channel switch active to false. If the
worker is running later, it will find the channel switch to not be
active anymore and returns immediately without changing anything.

Canceling the worker is done anyway when the interface goes down
(ieee80211_do_stop).
Reported-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

The channel switch notification should be sent under the
wdev/sdata-lock, preferably in the same moment as the channel change
happens, to avoid races by other callers (e.g. start/stop_ap).
This also adds the previously missing sdata_lock protection in
csa_finalize_work.
Reported-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

The csa finalize worker needs to change the beacon information (for
different modes). These are normally protected under rtnl lock, but the
csa finalize worker is called by drivers and should not acquire the RTNL
lock. Therefore change access protection for beacons to sdata/wdev lock.
Reported-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
[fix sdata_dereference]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

To avoid race conditions in functions which modify the beacon
information, lock these using the wdev lock. This is especially required
to avoid problems for csa handling functions which modify beacons but
can not be called under rtnl lock.
Reported-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

The local TSF timer is used to compute the timing offset between
mesh peers on beacon reception.  However, asking the device for
the TSF is not very accurate, so we prefer to use rx->mactime
if available.  In the latter case, calling drv_get_tsf() just
adds more delay into the RX path, so skip it if we can.
Signed-off-by: Bob Copeland <bob@cozybit.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Change cfg80211 and mac80211 to use cfg80211_mgmt_tx_params
struct to aggregate parameters for mgmt_tx functions.
This makes the functions' signatures less clumsy and allows
less painful parameters extension.
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
[fix all other drivers]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

There's a bug in tracking HT opmode changes in mac80211, it
fails to update the driver when the channel parameters don't
change.

Move the code to do the HT opmode checking independently of
the channel/bandwidth tracking.
Signed-off-by: Avri Altman <avri.altman@intel.com>
[edit commit message]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

All interface types now properly clean up their stations
using some form of sta_info_flush() themselves, so there's
no need to try it again at teardown. Remove the call to
get rid of the extra delay from the synchronize_net() and
rcu_barrier() calls.
Reported-by: Moshe Benji <moshe.benji@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Measure TX latency and jitter statistics per station per TID.
These Measurements are disabled by default and can be enabled
via debugfs.

Features included for each station's TID:

1. Keep count of the maximum and average latency of Tx frames.
2. Keep track of many frames arrived in a specific time range
   (need to enable through debugfs and configure the bins ranges)
Signed-off-by: Matti Gottlieb <matti.gottlieb@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

The beacon timers really shouldn't use any clock that is
subject to adjustments from userspace, particularly not
CLOCK_REALTIME. Use CLOCK_MONOTONIC_RAW instead.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

nla_put_flag needs a real nl80211 attribute id, not a wiphy flag bit.
While at it, split 5 and 10 MHz capability flags in case we ever need
to support hardware that can only do one of the two.

Also move the flag settings to the split-only information so we don't
increase the space needed for old userspace.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
[change location of flag setting]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

ATM minstrel_ht does not check whether a sampling rate is supported.
Unsupported rates attempts can trigger when there are holes in bitfields
of supported MCSes belonging to the same group (e.g many devices are
MCS32 capable without MCS33->39 capable, also we systematically have a
hole for CCK rates).
Drop any attempts to sample unsupported rates, as suggested by Felix.

This is not a problem in minstrel which fills a per STA sample table
with only supported rates (though only at init).
Signed-off-by: Karl Beldan <karl.beldan@rivierawaves.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

This lets us later reuse the more generic reg_dfs_region_str().
Signed-off-by: Luis R. Rodriguez <mcgrof@do-not-panic.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Signed-off-by: Luis R. Rodriguez <mcgrof@do-not-panic.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Only allow DFS to be set if the DFS regions agree.
Signed-off-by: Luis R. Rodriguez <mcgrof@do-not-panic.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

u8 was used in some other places, just stick to the enum,
this forces us to express the values that are expected.
Signed-off-by: Luis R. Rodriguez <mcgrof@do-not-panic.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

ATM, only the first array value returned by get_random_bytes is used.
This change moves the call to get_random_bytes from the nested loop it
is in to its parent.
While at it, replace get_random_bytes with prandom_bytes since PRNs are
way enough for the selection process.
After this, minstrel_ht reclaims 80 PR-bytes instead of 640 R-bytes.

minstrels use sample tables to probe different rates in a randomized
manner.
minstrel_ht inits one single sample table upon registration (during
subsys_initcalls) and minstrel uses one per STA addition in minstrel.
Signed-off-by: Karl Beldan <karl.beldan@rivierawaves.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Consecutive MCSes in [8*(NSS-1)->8*NSS[ have the same number NSS of
streams (except for MCS32 which is mishandled ATM).
ATM minstrel_ht uses MCS_GROUP_RATES in place of this 8 modulus.
This change replaces such occurences and by doing so allows for different
values of MCS_GROUP_RATES (e.g to cope with VHT MCS8,9).
Signed-off-by: Karl Beldan <karl.beldan@rivierawaves.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Add a new field to ieee80211_chanctx_conf to indicate
the min required channel configuration.

Tuning to a narrower channel might help reducing
the noise level and saving some power.

The min required channel definition is the max of
all min required channel definitions of the interfaces
bound to this channel context.

In AP mode, use 20MHz when there are no connected station.
When a new station is added/removed, calculate the new max
bandwidth supported by any of the stations (e.g. 80MHz when
80MHz and 40MHz stations are connected).

In other cases, simply use bss_conf.chandef as the
min required chandef.

Notify drivers about changes to this field by calling
drv_change_chanctx with a new CHANGE_MIN_WIDTH notification.
Signed-off-by: Eliad Peller <eliad@wizery.com>
Reviewed-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>

Introduce shift and mask defines for beamformee STS cap and number
of sounding dimensions cap as these can take any 3 bit value.
While at it also cleanup an unrequired parenthesis.
Signed-off-by: Eyal Shapira <eyal@wizery.com>
Reviewed-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>

There is no reason why we should have only one channel switch
announcement at a time for a single phy.  When support for channel
switch with multiple contexts and multiple vifs per context is
implemented, we will need the chandef data for each vif.  Move the
csa_chandef structure to sdata to prepare for this.
Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
[Fixed compilation with mesh]
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>