Currently, _everything_ in cfg80211 holds the RTNL, and if you
have a slow USB device (or a few) you can get some bad lock
contention on that.
Fix that by re-adding a mutex to each wiphy/rdev as we had at
some point, so we have locking for the wireless_dev lists and
all the other things in there, and also so that drivers still
don't have to worry too much about it (they still won't get
parallel calls for a single device).
Then, we can restrict the RTNL to a few cases where we add or
remove interfaces and really need the added protection. Some
of the global list management still also uses the RTNL, since
we need to have it anyway for netdev management, but we only
hold the RTNL for very short periods of time here.
Link: https://lore.kernel.org/r/20210122161942.81df9f5e047a.I4a8e1a60b18863ea8c5e6d3a0faeafb2d45b2f40@changeid
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> [marvell driver issues]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
We used to not require anything in terms of registering netdevs
with cfg80211, using a netdev notifier instead. However, in the
next patch reducing RTNL locking, this causes big problems, and
the simplest way is to just require drivers to do things better.
Change the registration/unregistration semantics to require the
drivers to call cfg80211_(un)register_netdevice() when this is
happening due to a cfg80211 request, i.e. add_virtual_intf() or
del_virtual_intf() (or if it somehow has to happen in any other
cfg80211 callback).
Otherwise, in other contexts, drivers may continue to use the
normal netdev (un)registration functions as usual.
Internally, we still use the netdev notifier and track (by the
new wdev->registered bool) if the wdev had already been added
to cfg80211 or not.
Link: https://lore.kernel.org/r/20210122161942.cf2f4b65e4e9.Ida8234e50da13eb675b557bac52a713ad4eddf71@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
NL80211_CMD_SET_SAR_SPECS is added to configure SAR from
user space. NL80211_ATTR_SAR_SPEC is used to pass the SAR
power specification when used with NL80211_CMD_SET_SAR_SPECS.
Wireless driver needs to register SAR type, supported frequency
ranges to wiphy, so user space can query it. The index in
frequency range is used to specify which sub band the power
limitation applies to. The SAR type is for compatibility, so later
other SAR mechanism can be implemented without breaking the user
space SAR applications.
Normal process is user space queries the SAR capability, and
gets the index of supported frequency ranges and associates the
power limitation with this index and sends to kernel.
Here is an example of message send to kernel:
8c 00 00 00 08 00 01 00 00 00 00 00 38 00 2b 81
08 00 01 00 00 00 00 00 2c 00 02 80 14 00 00 80
08 00 02 00 00 00 00 00 08 00 01 00 38 00 00 00
14 00 01 80 08 00 02 00 01 00 00 00 08 00 01 00
48 00 00 00
NL80211_CMD_SET_SAR_SPECS: 0x8c
NL80211_ATTR_WIPHY: 0x01(phy idx is 0)
NL80211_ATTR_SAR_SPEC: 0x812b (NLA_NESTED)
NL80211_SAR_ATTR_TYPE: 0x00 (NL80211_SAR_TYPE_POWER)
NL80211_SAR_ATTR_SPECS: 0x8002 (NLA_NESTED)
freq range 0 power: 0x38 in 0.25dbm unit (14dbm)
freq range 1 power: 0x48 in 0.25dbm unit (18dbm)
Signed-off-by: Carl Huang <cjhuang@codeaurora.org>
Reviewed-by: Brian Norris <briannorris@chromium.org>
Reviewed-by: Abhishek Kumar <kuabhs@chromium.org>
Link: https://lore.kernel.org/r/20201203103728.3034-2-cjhuang@codeaurora.org
[minor edits, NLA parse cleanups]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Johannes Berg says:
====================
Some updates:
* injection/radiotap updates for new test capabilities
* remove WDS support - even years ago when we turned
it off by default it was already basically unusable
* support for HE (802.11ax) rates for beacons
* support for some vendor-specific HE rates
* many other small features/cleanups
* tag 'mac80211-next-for-net-next-2020-11-13' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next: (21 commits)
nl80211: fix kernel-doc warning in the new SAE attribute
cfg80211: remove WDS code
mac80211: remove WDS-related code
rt2x00: remove WDS code
b43legacy: remove WDS code
b43: remove WDS code
carl9170: remove WDS code
ath9k: remove WDS code
wireless: remove CONFIG_WIRELESS_WDS
mac80211: assure that certain drivers adhere to DONT_REORDER flag
mac80211: don't overwrite QoS TID of injected frames
mac80211: adhere to Tx control flag that prevents frame reordering
mac80211: add radiotap flag to assure frames are not reordered
mac80211: save HE oper info in BSS config for mesh
cfg80211: add support to configure HE MCS for beacon rate
nl80211: fix beacon tx rate mask validation
nl80211/cfg80211: fix potential infinite loop
cfg80211: Add support to calculate and report 4096-QAM HE rates
cfg80211: Add support to configure SAE PWE value to drivers
ieee80211: Add definition for WFA DPP
...
====================
Link: https://lore.kernel.org/r/20201113101148.25268-1-johannes@sipsolutions.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Add support to configure SAE PWE preference from userspace to drivers in
both AP and STA modes. This is needed for cases where the driver takes
care of Authentication frame processing (SME in the driver) so that
correct enforcement of the acceptable PWE derivation mechanism can be
performed.
The userspace applications can pass the sae_pwe value using the
NL80211_ATTR_SAE_PWE attribute in the NL80211_CMD_CONNECT and
NL80211_CMD_START_AP commands to the driver. This allows selection
between the hunting-and-pecking loop and hash-to-element options for PWE
derivation. For backwards compatibility, this new attribute is optional
and if not included, the driver is notified of the value being
unspecified.
Signed-off-by: Rohan Dutta <drohan@codeaurora.org>
Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
Link: https://lore.kernel.org/r/20201027100910.22283-1-jouni@codeaurora.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Pull documentation updates from Mauro Carvalho Chehab:
"A series of patches addressing warnings produced by make htmldocs.
This includes:
- kernel-doc markup fixes
- ReST fixes
- Updates at the build system in order to support newer versions of
the docs build toolchain (Sphinx)
After this series, the number of html build warnings should reduce
significantly, and building with Sphinx 3.1 or later should now be
supported (although it is still recommended to use Sphinx 2.4.4).
As agreed with Jon, I should be sending you a late pull request by the
end of the merge window addressing remaining issues with docs build,
as there are a number of warning fixes that depends on pull requests
that should be happening along the merge window.
The end goal is to have a clean htmldocs build on Kernel 5.10.
PS. It should be noticed that Sphinx 3.0 is not currently supported,
as it lacks support for C domain namespaces. Such feature, needed in
order to document uAPI system calls with Sphinx 3.x, was added only on
Sphinx 3.1"
* tag 'docs/v5.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (75 commits)
PM / devfreq: remove a duplicated kernel-doc markup
mm/doc: fix a literal block markup
workqueue: fix a kernel-doc warning
docs: virt: user_mode_linux_howto_v2.rst: fix a literal block markup
Input: sparse-keymap: add a description for @sw
rcu/tree: docs: document bkvcache new members at struct kfree_rcu_cpu
nl80211: docs: add a description for s1g_cap parameter
usb: docs: document altmode register/unregister functions
kunit: test.h: fix a bad kernel-doc markup
drivers: core: fix kernel-doc markup for dev_err_probe()
docs: bio: fix a kerneldoc markup
kunit: test.h: solve kernel-doc warnings
block: bio: fix a warning at the kernel-doc markups
docs: powerpc: syscall64-abi.rst: fix a malformed table
drivers: net: hamradio: fix document location
net: appletalk: Kconfig: Fix docs location
dt-bindings: fix references to files converted to yaml
memblock: get rid of a :c:type leftover
math64.h: kernel-docs: Convert some markups into normal comments
media: uAPI: buffer.rst: remove a left-over documentation
...
Changeset df78a0c0b6 ("nl80211: S1G band and channel definitions")
added a new parameter, but didn't add the corresponding kernel-doc
markup, as repoted when doing "make htmldocs":
./include/net/cfg80211.h:471: warning: Function parameter or member 's1g_cap' not described in 'ieee80211_supported_band'
Add a documentation for it.
Fixes: df78a0c0b6 ("nl80211: S1G band and channel definitions")
Signed-off-by: Thomas Pedersen <thomas@adapt-ip.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
NL80211_ATTR_S1G_CAPABILITY can be passed along with
NL80211_ATTR_S1G_CAPABILITY_MASK to NL80211_CMD_ASSOCIATE
to indicate S1G capabilities which should override the
hardware capabilities in eg. the association request.
Signed-off-by: Thomas Pedersen <thomas@adapt-ip.com>
Link: https://lore.kernel.org/r/20200922022818.15855-4-thomas@adapt-ip.com
[johannes: always require both attributes together, commit message]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This patch adds new attributes to support unsolicited broadcast
probe response transmission used for in-band
discovery in 6GHz band (IEEE P802.11ax/D6.0 26.17.2.3.2, AP behavior for
fast passive scanning).
The new attribute, NL80211_ATTR_UNSOL_BCAST_PROBE_RESP, is nested which
supports following parameters:
(1) NL80211_UNSOL_BCAST_PROBE_RESP_ATTR_INT - Packet interval
(2) NL80211_UNSOL_BCAST_PROBE_RESP_ATTR_TMPL - Template data
Signed-off-by: Aloka Dixit <alokad@codeaurora.org>
Link: https://lore.kernel.org/r/010101747a946698-aac263ae-2ed3-4dab-9590-0bc7131214e1-000000@us-west-2.amazonses.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
S1G channels have a single width defined per frequency, so
derive it from the channel flags with
ieee80211_s1g_channel_width().
Also support setting an S1G channel where control frequency may
differ from operating, and add some basic validation to
ensure the control channel is with the operating.
Signed-off-by: Thomas Pedersen <thomas@adapt-ip.com>
Link: https://lore.kernel.org/r/20200908190323.15814-6-thomas@adapt-ip.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Currently, before being able to forward a packet between two 802.11s
nodes, both a PLINK handshake is performed upon receiving a beacon and
then later a PREQ/PREP exchange for path discovery is performed on
demand upon receiving a data frame to forward.
When running a mesh protocol on top of an 802.11s interface, like
batman-adv, we do not need the multi-hop mesh routing capabilities of
802.11s and usually set mesh_fwding=0. However, even with mesh_fwding=0
the PREQ/PREP path discovery is still performed on demand. Even though
in this scenario the next hop PREQ/PREP will determine is always the
direct 11s neighbor node.
The new mesh_nolearn parameter allows to skip the PREQ/PREP exchange in
this scenario, leading to a reduced delay, reduced packet buffering and
simplifies HWMP in general.
mesh_nolearn is still rather conservative in that if the packet destination
is not a direct 11s neighbor, it will fall back to PREQ/PREP path
discovery.
For normal, multi-hop 802.11s mesh routing it is usually not advisable
to enable mesh_nolearn as a transmission to a direct but distant neighbor
might be worse than reaching that same node via a more robust /
higher throughput etc. multi-hop path.
Cc: Sven Eckelmann <sven@narfation.org>
Cc: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Linus Lüssing <ll@simonwunderlich.de>
Link: https://lore.kernel.org/r/20200617073034.26149-1-linus.luessing@c0d3.blue
[fix nl80211 policy to range 0/1 only]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The low level driver adds its own opaque information
in the BSS table in the cfg80211_bss structure.
The low level driver may need to signal that this information
is no longer relevant and needs to be recreated.
Add an API to allow the low level driver to do that.
iwlwifi needs this because it keeps there an information about
the firmware's internal clock. This is kept in mac80211's
struct ieee80211_bss::sync_device_ts.
This information is populated while we scan, we add the
internal firmware's clock to each beacon which allows us to
program the firmware correctly after association so that
it'll know when (in terms of its internal clock) the DTIM
and TBTT will happen.
When the firmware is reset this internal clock is reset as
well and ieee80211_bss::sync_device_ts is no longer accurate.
iwlwifi will call this new API any time the firmware is started.
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Link: https://lore.kernel.org/r/20200625111524.3992-1-emmanuel.grumbach@intel.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Lockdep reports that we may deadlock because we take the RTNL on
the work struct, but flush it under RTNL. Clearly, it's correct.
In practice, this can happen when doing rfkill on an active device.
Fix this by moving the work struct to the wiphy (registered dev)
layer, and iterate over all the wdevs inside there. This then
means we need to track which one of them has work to do, so we
don't update to the driver for all wdevs all the time.
Also fix a locking bug I noticed while working on this - the
registrations list is iterated as if it was an RCU list, but it
isn't handle that way - and we need to lock now for the update
flag anyway, so remove the RCU.
Fixes: 6cd536fe62 ("cfg80211: change internal management frame registration API")
Reported-by: Markus Theil <markus.theil@tu-ilmenau.de>
Reported-and-tested-by: Kenneth R. Crudup <kenny@panix.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Link: https://lore.kernel.org/r/20200604120420.b1dc540a7e26.I55dcca56bb5bdc5d7ad66a36a0b42afd7034d8be@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20200507183909.GA12993@embeddedor
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Drivers may wish to report the RX frequency in units of
KHz. Provide cfg80211_rx_mgmt_khz() and wrap it with
cfg80211_rx_mgmt() so exisiting drivers which can't report
KHz anyway don't need to change. Add a similar wrapper for
cfg80211_report_obss_beacon() so the frequency units stay
somewhat consistent.
This doesn't actually change the nl80211 API yet.
Signed-off-by: Thomas Pedersen <thomas@adapt-ip.com>
Link: https://lore.kernel.org/r/20200430172554.18383-2-thomas@adapt-ip.com
[fix mac80211 calling the non-khz version of obss beacon report,
drop trace point name changes]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Johannes Berg says:
====================
One batch of changes, containing:
* hwsim improvements from Jouni and myself, to be able to
test more scenarios easily
* some more HE (802.11ax) support
* some initial S1G (sub 1 GHz) work for fractional MHz channels
* some (action) frame registration updates to help DPP support
* along with other various improvements/fixes
====================
Signed-off-by: David S. Miller <davem@davemloft.net>