Max Schulze reports crashes with brcmfmac. The reason seems
to be a race between userspace removing the CQM config and
the driver calling cfg80211_cqm_rssi_notify(), where if the
data is freed while cfg80211_cqm_rssi_notify() runs it will
crash since it assumes wdev->cqm_config is set. This can't
be fixed with a simple non-NULL check since there's nothing
we can do for locking easily, so use RCU instead to protect
the pointer, but that requires pulling the updates out into
an asynchronous worker so they can sleep and call back into
the driver.

Since we need to change the free anyway, also change it to
go back to the old settings if changing the settings fails.

Reported-and-tested-by: Max Schulze <max.schulze@online.de>
Closes: https://lore.kernel.org/r/ac96309a-8d8d-4435-36e6-6d152eb31876@online.de
Fixes: 4a4b8169501b ("cfg80211: Accept multiple RSSI thresholds for CQM")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).

As found with Coccinelle[1], add __counted_by for struct cfg80211_cqm_config.

[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci

Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: linux-wireless@vger.kernel.org
Cc: netdev@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Link: https://lore.kernel.org/r/20230817211531.4193219-2-keescook@chromium.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

STA MLD setup links may get removed if AP MLD remove the corresponding
affiliated APs with Multi-Link reconfiguration as described in
P802.11be_D3.0, section 35.3.6.2.2 Removing affiliated APs. Currently,
there is no support to notify such operation to cfg80211 and userspace.

Add support for the drivers to indicate STA MLD setup links removal to
cfg80211 and notify the same to userspace. Upon receiving such
indication from the driver, clear the MLO links information of the
removed links in the WDEV.

Signed-off-by: Veerendranath Jakkam <quic_vjakkam@quicinc.com>
Link: https://lore.kernel.org/r/20230317142153.237900-1-quic_vjakkam@quicinc.com
[rename function and attribute, fix kernel-doc]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Move the scan done work to the new wiphy work to
simplify the code a bit.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

This work can now trivially be converted, it behaves
identical either way.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Add a work abstraction at the cfg80211 level that will always
hold the wiphy_lock() for any work executed and therefore also
can be canceled safely (without waiting) while holding that.
This improves on what we do now as with the new wiphy works we
don't have to worry about locking while cancelling them safely.

Also, don't let such works run while the device is suspended,
since they'll likely need to interact with the device. Flush
them before suspend though.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

This reverts commit b8676221f00d ("cfg80211: Add support for
static WEP in the driver") since no driver ever ended up using
it.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

In case of 4way handshake offload, transition disable policy
updated by the AP during EAPOL 3/4 is not updated to the upper layer.
This results in mismatch between transition disable policy
between the upper layer and the driver. This patch addresses this
issue by updating transition disable policy as part of port
authorization indication.

Signed-off-by: Vinayak Yadawad <vinayak.yadawad@broadcom.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

This was missing earlier, we need to remove links when
interfaces are being destroyed, and we also need to
stop (AP) operations when a link is being destroyed.
Address these issues to remove many warnings that will
otherwise appear in mac80211.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

The race described by the comment in mac80211 hasn't existed
since the locking rework to use the same lock and for MLO we
need to pass the AP MLD address, so just pass the BSSID or
AP MLD address instead of the BSS struct pointer, and adjust
all the code accordingly.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>