In the spec, CSA is defined roughly as follows:
- TBTT x: beacon with CSA, count=n (old channel)
- TBTT x+1: beacon with CSA, count=n-1 (old channel)
- TBTT x+n-1: beacon with CSA, count=1 (old channel)
"A Channel Switch Count field set to 1 indicates that the switch
occurs immediately before the next TBTT.
- TBTT x+n: beacon without CSA (new channel)
When we detect it, we currently schedule the CSA event to
be at 10 TUs before TBTT x+n-1, for a beacon interval, to
give us quiet time.
When this event *starts*, we currently notify mac80211
that the channel switch happened, which causes us to add
a session protection event to listen for the first beacon
(and enable TX etc. when that arrives).
We don't even ask for a notification when this event ends
so the code that handles that is effectively dead code.
The session protection duration is 3 beacon intervals,
scheduled at 10 TU before TBTT x+n-1. It will thus end
just before TBTT x+n+2.
Unfortunately, if the AP doesn't transmit or we miss just
the first two beacons on the new channel, then this will
cause us to disconnect. Or even just one, if the AP isn't
quite aligned with the TBTT after the switch.
However, listening to the _end_ of the time event isn't
what we want either, because we want all the new PHY and
other config that needs to come from mac80211 to start
early, so we have a head-start for the new channel, since
we're not going to use the old one anyway for this time.
So since we don't really have anything better to do at
this time, and this is relatively rare, just make the
session protection use 5x the beacon interval instead of
just 3x, so it's more likely we catch a beacon even if
the AP neglected to send it, or we just miss it.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20230830112059.a74176bac37c.I029a2ebcd1b5012327c728ffa1d33fac19cfdf4b@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The code that sets up the assoc link will currently take the BSS
element data from the beacon only. This is correct for some of
the data, notably the timing and the "have_beacon", but all the
data about MBSSID and EHT really doesn't need to be taken from
there, and if the EHT puncturing is misconfigured on the AP but
we didn't receive a beacon yet, this causes us to connect but
immediately disconnect upon receiving the first beacon, rather
than connecting without EHT in the first place.
Change the code to take MBSSID and EHT data also from the probe
response, for a better picture of what the BSS capabilities are
and to avoid that EHT puncturing problem.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20230827135854.3c7e52d49482.Iba6b672f6dc74b45bba26bc497e953e27da43ef9@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
In mesh_fast_tx_flush_addr() we already hold the lock, so
don't need additional hashtable RCU protection. Use the
rhashtable_lookup_fast() variant to avoid RCU protection
warnings.
Fixes: d5edb9ae8d ("wifi: mac80211: mesh fast xmit support")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
There were are a number of cases in mac80211 and iwlwifi (at
least) that used the sband->iftype_data pointer directly,
instead of using the accessors to find the right array entry
to use.
Make sparse warn when such a thing is done.
To not have a lot of casts, add two helper functions/macros
- ieee80211_set_sband_iftype_data()
- for_each_sband_iftype_data()
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
As previously reported by Alexander, whose commit 69403bad97
("wifi: mac80211: sdata can be NULL during AMPDU start") I'm
reverting as part of this commit, there's a race between station
destruction and aggregation setup, where the aggregation setup
can happen while the station is being removed and queue the work
after ieee80211_sta_tear_down_BA_sessions() has already run in
__sta_info_destroy_part1(), and thus the worker will run with a
now freed station. In his case, this manifested in a NULL sdata
pointer, but really there's no guarantee whatsoever.
The real issue seems to be that it's possible at all to have a
situation where this occurs - we want to stop the BA sessions
when doing _part1, but we cannot be sure, and WLAN_STA_BLOCK_BA
isn't necessarily effective since we don't know that the setup
isn't concurrently running and already got past the check.
Simply call ieee80211_sta_tear_down_BA_sessions() again in the
second part of station destruction, since at that point really
nothing else can hold a reference to the station any more.
Also revert the sdata checks since those are just misleading at
this point.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When compiling with clang 16.0.6 and CONFIG_FORTIFY_SOURCE=y, I've
noticed the following (somewhat confusing due to absence of an actual
source code location):
In file included from drivers/net/wireless/virtual/mac80211_hwsim.c:18:
In file included from ./include/linux/slab.h:16:
In file included from ./include/linux/gfp.h:7:
In file included from ./include/linux/mmzone.h:8:
In file included from ./include/linux/spinlock.h:56:
In file included from ./include/linux/preempt.h:79:
In file included from ./arch/x86/include/asm/preempt.h:9:
In file included from ./include/linux/thread_info.h:60:
In file included from ./arch/x86/include/asm/thread_info.h:53:
In file included from ./arch/x86/include/asm/cpufeature.h:5:
In file included from ./arch/x86/include/asm/processor.h:23:
In file included from ./arch/x86/include/asm/msr.h:11:
In file included from ./arch/x86/include/asm/cpumask.h:5:
In file included from ./include/linux/cpumask.h:12:
In file included from ./include/linux/bitmap.h:11:
In file included from ./include/linux/string.h:254:
./include/linux/fortify-string.h:592:4: warning: call to '__read_overflow2_field'
declared with 'warning' attribute: detected read beyond size of field (2nd
parameter); maybe use struct_group()? [-Wattribute-warning]
__read_overflow2_field(q_size_field, size);
The compiler actually complains on 'mac80211_hwsim_get_et_strings()' where
fortification logic inteprets call to 'memcpy()' as an attempt to copy the
whole 'mac80211_hwsim_gstrings_stats' array from its first member and so
issues an overread warning. This warning may be silenced by passing
an address of the whole array and not the first member to 'memcpy()'.
Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
Link: https://lore.kernel.org/r/20230829094140.234636-1-dmantipov@yandex.ru
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
We currently call ieee80211_txq_teardown_flows() as part
of ieee80211_remove_interfaces(), but that's not really
right in case of HW registration failures, specifically
rate control. Call it separately to fix that issue.
Reported-by: Zhengchao Shao <shaozhengchao@huawei.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Since we're now protecting everything with the wiphy mutex
(and were really using it for almost everything before),
there's no longer any real reason to have a separate wdev
mutex. It may feel better, but really has no value.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
We now hold the wiphy mutex everywhere that we use or
needed the iflist_mtx, so we don't need this mutex any
more in mac80211. However, drivers may also iterate,
and in some cases (e.g. mt76) do so from high-priority
contexts. Thus, keep the mutex around but remove its
usage in mac80211 apart from those driver-visible parts
that are still needed.
Most of this change was done automatically with spatch,
with the parts that are still needed as described above
reverted manually.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
We now hold the wiphy mutex everywhere that we use or
needed the local->mtx, so we don't need this mutex any
more. Remove it.
Most of this change was done automatically with spatch.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
We now hold the wiphy mutex everywhere that we use or
needed the A-MPDU locking, so we don't need this mutex
any more. Remove it.
Most of this change was done automatically with spatch.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
We now hold the wiphy mutex everywhere that we use or
needed the chanctx_mtx, so we don't need this mutex any
more. Remove it.
Most of this change was done automatically with spatch.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
We now hold the wiphy mutex everywhere that we use or
needed the key_mtx, so we don't need this mutex any
more. Remove it.
Most of this change was done automatically with spatch.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
We now hold the wiphy mutex everywhere that we use or
needed the sta_mtx, so we don't need this mutex any
more. Remove it.
Most of this change was done automatically with spatch.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
We want to ensure everything holds the wiphy lock,
so also extend that to the MAC change callback.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
We want to extend the wiphy locking to the interface list,
so move that into the section locked with the wiphy lock.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
We want to replace the locking in mac80211 by just the wiphy
mutex, so hold the lock here around concurrency checks for
the future where the chanctx_mtx used inside goes away.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
We should hold the wiphy mutex here since we're going
to call the driver and want to remove the sta_mtx.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This might seem pretty pointless rather than changing the locking
immediately, but it seems safer to run for a while with checks and
the old locking scheme, and then remove the wdev lock later.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
We have the RTNL here for the iteration, but we need to lock
each wiphy separately as well for using its data. Hold the
wiphy lock for all of the ones in the iteration. Note that
this implies we cannot already hold the wiphy mutex for the
wiphy passed by the argument, but that's true now.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Since we will want to remove the wdev lock in the future,
lock the wiphy here to iterate and for checking the status
of the connections.
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Since we will want to remove the wdev lock in the future,
lock the wiphy here to iterate and check the flags.
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Check that we hold the wiphy mutex in the ops when
calling the driver, since we're now on our way to
always hold it, and simplify the locking.
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Again this should be per link and will get cancellation
issues, move it to a wiphy work.
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This work should be made per link as well, and then
will have cancellation issues. Moving it to a wiphy
work already fixes those beforehand.
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
