cfg80211_chan_def and ieee80211_channel recently gained a
frequency offset component. Handle this where it makes
sense (potentially required by S1G channels).
For IBSS, TDLS, CSA, and ROC we return -EOPNOTSUPP if a
channel with frequency offset is passed, since they may or
may not work. Once someone tests and verifies these
commands work on thos types of channels, we can remove
that error.
join_ocb and join_mesh look harmless because they use a
simple ieee80211_vif_use_channel(), which is using an
already verified channel, so we let those through.
Signed-off-by: Thomas Pedersen <thomas@adapt-ip.com>
Link: https://lore.kernel.org/r/20200402011810.22947-4-thomas@adapt-ip.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This low level driver can find it useful to get the vif
when a remain on channel session is cancelled.
iwlwifi will need this soon.
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Link: https://lore.kernel.org/r/20190723180001.5828-1-emmanuel.grumbach@intel.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Based on 2 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 4122 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When the offchannel TX wait time expires, send the appropriate event.
Signed-off-by: James Prestwood <james.prestwood@linux.intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Support the new random SN and minimal probe request contents
scan flags for the case of software scan - for hardware scan
the drivers need to opt in, but may need to do only that,
depending on their implementation.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.
Notice that in some cases I replaced "fall through on else" and
"otherwise fall through" comments with just a "fall through" comment,
which is what GCC is expecting to find.
Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When HW ROC is supported it is possible that after the HW notified
that the ROC has started, the ROC was cancelled and another ROC was
added while the hw_roc_start worker is waiting on the mutex (since
cancelling the ROC and adding another one also holds the same mutex).
As a result, the hw_roc_start worker will continue to run after the
new ROC is added but before it is actually started by the HW.
This may result in notifying userspace that the ROC has started before
it actually does, or in case of management tx ROC, in an attempt to
tx while not on the right channel.
In addition, when the driver will notify mac80211 that the second ROC
has started, mac80211 will warn that this ROC has already been
notified.
Fix this by flushing the hw_roc_start work before cancelling an ROC.
Cc: stable@vger.kernel.org
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>
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>
When using IEEE 802.11r FT OVER-DS roaming with AP_VLAN, hostapd needs to
send out a frame using CMD_FRAME for a station assigned to an AP_VLAN
interface.
Right now, the userspace needs to give the exact AP_VLAN interface index
for CMD_FRAME; hostapd does not do this. Additionally, userspace cannot
use GET_STATION to query the AP_VLAN ifidx, as while GET_STATION finds
stations assigned to AP_VLAN even if the AP iface is queried, it does not
return AP_VLAN ifidx (it returns the queried one).
This breaks IEEE 802.11r over_ds with vlans, as the reply frame does not
get out. This patch fixes this by using get_sta_bss for CMD_FRAME.
Signed-off-by: Michael Braun <michael-dev@fami-braun.de>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This code doesn't do much besides allowing to start and
stop the vif.
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Ayala Beker <ayala.beker@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This allows user space to start/stop NAN interface.
A NAN interface is like P2P device in a few aspects: it
doesn't have a netdev associated to it.
Add the new interface type and prevent operations that
can't be executed on NAN interface like scan.
Define several attributes that may be configured by user space
when starting NAN functionality (master preference and dual
band operation)
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
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>
Defer ROC requests during hw restart, as the driver
might not be fully configured in this stage (e.g.
channel contexts were not added yet)
Signed-off-by: Eliad Peller <eliadx.peller@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Ilan's previous commit 1b894521e6 ("mac80211: handle HW
ROC expired properly") neglected to take into account that
hw_begun was now always set in the software implementation
as well as the offloaded case.
Fix hw_begun to only apply to the offloaded case to make
the check in Ilan's commit safe and correct.
Reported-by: Jouni Malinen <j@w1.fi>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The current (new) code recalculates the new work timeout
for software remain-on-channel whenever any item started.
In two of the callers of ieee80211_handle_roc_started(),
this is completely pointless since they're for hardware
and will skip the recalculation entirely; it's necessary
only in the case of having just added a new item to the
list, as in the last remaining case the recalculation had
just been done.
This last case, however, is also problematic - if one of
the items on the list actually expires during the recalc
the list iteration outside becomes corrupted and crashes.
Fix this by moving the recalculation to the only place
where it's required.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
In case of HW ROC, when the driver reports that the ROC expired,
it is not sufficient to purge the ROCs based on the remaining
time, as it possible that the device finished the ROC session
before the actual requested duration.
To handle such cases, in case of ROC expired notification from
the driver, complete all the ROCs which are marked with hw_begun,
regardless of the remaining duration.
Signed-off-by: Ilan Peer <ilan.peer@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When cancelling, you can cancel "any" (first in list) mgmt-tx
or remain-on-channel operation by using the value 0 for the
cookie along with the *opposite* operation, i.e.
* cancel the first mgmt-tx by cancelling roc with 0 cookie
* cancel the first roc by cancelling mgmt-tx with 0 cookie
This isn't really that bad since userspace should only pass
cookies that we gave it, but could lead to hard-to-debug
issues so better prevent it and reject zero values since we
never hand those out.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Jouni found a bug in the remain-on-channel logic: when a short item
is queued, a long item is combined with it extending the original
one, and then the long item is deleted, the timeout doesn't go back
to the short one, and the short item ends up taking a long time. In
this case, this showed as blocking scan when running two test cases
back to back - the scan from the second was delayed even though all
the remain-on-channel items should long have been gone.
Fixing this with the current data structures turns out to be a bit
complicated, we just remove the long item from the dependents list
right now and don't recalculate the timeouts.
There's a somewhat similar bug where we delete the short item and
all the dependents go with it; to fix this we'd have to move them
from the dependents to the real list.
Instead of trying to do that, rewrite the code to not have all this
complexity in the data structures: use a single list and allow more
than one entry in it being marked as started. This makes the code a
bit more complex, the worker needs to understand that it might need
to just remove one of the started items, while keeping the device
off-channel, but that's not more complicated than the nested data
structures.
This then fixes both issues described, and makes it easier to also
limit the overall off-channel time when combining.
TODO: as before, with hardware remain-on-channel, deleting an item
after combining results in cancelling them all - we can keep track
of the time elapsed and only cancel after that to fix this.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Since the cookie is assigned inside ieee80211_make_ack_skb()
now, we no longer need to return the ack_skb as the cookie
and can simplify the function's return and the callers. Also
rename it to ieee80211_attach_ack_skb() to more accurately
reflect its purpose.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This is quite a bit of code that logically depends here since
it has to deal with all the remain-on-channel logic.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
If a mgmt-tx operation is aborted before it runs, the wrong
cookie is reported back to userspace, and the ack_skb gets
leaked since the frame is freed directly instead of freeing
it using ieee80211_free_txskb(). Fix that.
Fixes: 3b79af973c ("mac80211: stop using pointers as userspace cookies")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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>
As we're running out of hardware capability flags pretty quickly,
convert them to use the regular test_bit() style unsigned long
bitmaps.
This introduces a number of helper functions/macros to set and to
test the bits, along with new debugfs code.
The occurrences of an explicit __clear_bit() are intentional, the
drivers were never supposed to change their supported bits on the
fly. We should investigate changing this to be a per-frame flag.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When roaming / suspending, it makes no sense to wait until
the transmit queues of the device are empty. In extreme
condition they can be starved (VO saturating the air), but
even in regular cases, it is pointless to delay the roaming
because the low level driver is trying to send packets to
an AP which is far away. We'd rather drop these packets and
let TCP retransmit if needed. This will allow to speed up
the roaming.
For suspend, the explanation is even more trivial.
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Sometimes different vifs may be stopping the queues for the same
reason (e.g. when several interfaces are performing a channel switch).
Instead of using a bitmask for the reasons, use an integer that holds
a refcount instead. In order to keep it backwards compatible,
introduce a boolean in some functions that tell us whether the queue
stopping should be refcounted or not. For now, use not refcounted for
all calls to keep it functionally the same as before.
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Jouni reported that if a remain-on-channel was active on the
same channel as the current operating channel, then the ROC
would start, but any frames transmitted using mgmt-tx on the
same channel would get delayed until after the ROC.
The reason for this is that the ROC starts, but doesn't have
any handling for "remain on the same channel", so it stops
the interface queues. The later mgmt-tx then puts the frame
on the interface queues (since it's on the current operating
channel) and thus they get delayed until after the ROC.
To fix this, add some logic to handle remaining on the same
channel specially and not stop the queues etc. in this case.
This not only fixes the bug but also improves behaviour in
this case as data frames etc. can continue to flow.
Cc: stable@vger.kernel.org
Reported-by: Jouni Malinen <j@w1.fi>
Tested-by: Jouni Malinen <j@w1.fi>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Jouni reported that when doing off-channel transmissions mixed
with on-channel transmissions, the on-channel ones ended up on
the off-channel in some cases.
The reason for that is that during the refactoring of the off-
channel code, I lost the part that stopped all activity and as
a consequence the on-channel frames (including data frames)
were no longer queued but would be transmitted on the temporary
channel.
Fix this by simply restoring the lost activity stop call.
Cc: stable@vger.kernel.org
Fixes: 2eb278e083 ("mac80211: unify SW/offload remain-on-channel")
Reported-by: Jouni Malinen <j@w1.fi>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
mac80211 scan processing could get stuck if roc work for pending, but
not started when a scan request was deferred due to such roc item.
Normally the deferred scan would be started from
ieee80211_start_next_roc(), but ieee80211_sw_roc_work() calls that only
if the finished ROC was started. Fix this by calling
ieee80211_run_deferred_scan() in the case the last ROC was not actually
started.
This issue was hit relatively easily in P2P find operations where Listen
state (remain-on-channel) and Search state (scan) are repeated in a
loop.
Signed-off-by: Jouni Malinen <j@w1.fi>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
They can't really be executed while suspended and could
trigger work warnings, so abort all ROC items. When the
system resumes the notifications about this will be
delivered to userspace which can then act accordingly
(though it will assume they were canceled/finished.)
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
If a ROC item is canceled just as it expires, the work
struct may be scheduled while it is running (and waiting
for the mutex). This results in it being run after being
freed, which obviously crashes.
To fix this don't free it when aborting is requested but
instead mark it as "to be freed", which makes the work a
no-op and allows freeing it outside.
Cc: stable@vger.kernel.org [3.6+]
Reported-by: Jouni Malinen <j@w1.fi>
Tested-by: Jouni Malinen <j@w1.fi>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Sometimes queues are flushed in the middle of
operation, which can lead to driver issues.
Stop queues temporarily, while flushing, to
avoid transmitting new packets while they are
being flushed.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
There are a number of situations in which mac80211 only
really needs to flush queues for one virtual interface,
and in fact during this frames might be transmitted on
other virtual interfaces. Calculate and pass a queue
bitmap to the driver so it knows which queues to flush.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Some devices can handle remain on channel requests differently
based on the request type/priority. Add support to
differentiate between different ROC types, i.e., indicate that
the ROC is required for sending managment frames.
Signed-off-by: Ilan Peer <ilan.peer@intel.com>
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
We've got a couple of races when enabling powersave with an AP for
off-channel operation. The first is fairly simple. If we go off-channel
before the nullfunc frame to enable PS is transmitted then it may not be
received by the AP. Add a flush after enabling off-channel PS to prevent
this from happening.
The second race is a bit more subtle. If the driver supports QoS and has
frames queued when the nullfunc frame is queued, those frames may get
transmitted after the nullfunc frame. If PM is not set then the AP is
being told that we've exited PS before we go off-channel and may try to
deliver frames. To prevent this, add a flush after stopping the queues
but before passing the nullfunc frame to the driver.
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Scans currently work by stopping the netdev tx queues but leaving the
mac80211 queues active. This stops the flow of incoming packets while
still allowing mac80211 to transmit nullfunc and probe request frames to
facilitate scanning. However, the driver may try to wake the mac80211
queues while in this state, which will also wake the netdev queues.
To prevent this, add a new queue stop reason,
IEEE80211_QUEUE_STOP_REASON_OFFCHANNEL, to be used when stopping the tx
queues for off-channel operation. This prevents the netdev queues from
waking when a driver wakes the mac80211 queues.
This also stops all frames from being transmitted, even those meant to
be sent off-channel. Add a new tx control flag,
IEEE80211_TX_CTL_OFFCHAN_TX_OK, which allows frames to be transmitted
when the queues are stopped only for the off-channel stop reason. Update
all locations transmitting off-channel frames to use this flag.
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Since:
commit b23b025fe2
Author: Ben Greear <greearb@candelatech.com>
Date: Fri Feb 4 11:54:17 2011 -0800
mac80211: Optimize scans on current operating channel.
we do not disable PS while going back to operational channel (on
ieee80211_scan_state_suspend) and deffer that until scan finish.
But since we are allowed to send frames, we can send a frame to AP
without PM bit set, so disable PS on AP side. Then when we switch
to off-channel (in ieee80211_scan_state_resume) we do not enable PS.
Hence we are off-channel with PS disabled, frames are not buffered
by AP.
To fix remove offchannel_ps_disable argument and always enable PS when
going off-channel and disable it when going on-channel, like it was
before.
Cc: stable@vger.kernel.org # 2.6.39+
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Tested-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Instead of calculating in ieee80211_bss_info_change_notify()
whether beaconing should be enabled or not, set it in the
correct places in the callers. This simplifies the logic in
this function at the expense of offchannel, but is also more
robust.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
It fixes a potential crash when receiving an LLCP HDLC frame acking a frame
that is not the last sent one. In that case we may dereference an already
freed pointer.
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Merge tag 'nfc-fixes-3.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/sameo/nfc-3.0
This is an NFC LLCP fix for 3.7 and contains only one patch.
It fixes a potential crash when receiving an LLCP HDLC frame acking a frame
that is not the last sent one. In that case we may dereference an already
freed pointer.
Felix Liao reported that when an interface is set DOWN
while another interface is executing a ROC, the warning
in ieee80211_start_next_roc() (about the first item on
the list having started already) triggers.
This is because ieee80211_roc_purge() calls it even if
it never actually changed the list of ROC items. To fix
this, simply remove the function call. If it is needed
then it will be done by the ieee80211_sw_roc_work()
function when the ROC item that is being removed while
active is cleaned up.
Cc: stable@vger.kernel.org
Reported-by: Felix Liao <Felix.Liao@watchguard.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
As mwifiex (and mac80211 in the software case) are the
only drivers actually implementing remain-on-channel
with channel type, userspace can't be relying on it.
This is the case, as it's used only for P2P operations
right now.
Rather than adding a flag to tell userspace whether or
not it can actually rely on it, simplify all the code
by removing the ability to use different channel types.
Leave only the validation of the attribute, so that if
we extend it again later (with the needed capability
flag), it can't break userspace sending invalid data.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Drivers (e.g. wl12xx) might need to know the vif
to roc on (mainly in order to configure the
rx filters correctly).
Add the vif to the op params, and update the current
users (iwlwifi) to use the new api.
Signed-off-by: Eliad Peller <eliad@wizery.com>
[fix hwsim]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Instead of using the pointer which can be re-used
fairly quickly due to allocator patterns and then
makes debugging difficult, maintain a counter and
use its value. Since it's a 64-bit value it can't
really wrap, but catch that case anyway since it
most likely points to a bug somewhere.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Instead of operating on a single channel only,
use the new channel context infrastructure in
all mac80211 code.
This enables drivers that want to use the new
channel context infrastructure to use multiple
channels, while nothing should change for all
the other drivers that don't support it.
Right now this disables both TX power settings
and spatial multiplexing powersave. Both need
to be re-enabled on a channel context basis.
Additionally, when channel contexts are used
drop the connection when channel switch is
received rather than trying to handle it. This
will have to be improved later.
[With fixes from Eliad and Emmanuel incorporated]
Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Depending on the driver, channel contexts may be used or
not. If they are used, the driver must have support for
hardware scan and remain-on-channel; otherwise the driver
must not advertise support for multiple channels.
Also prohibit WDS type interfaces when channel contexts
are to be used as there's no clear definition of which
channel they use.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Using list_move() instead of list_del() + list_add().
spatch with a semantic match is used to found this problem.
(http://coccinelle.lip6.fr/)
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>