• Johannes Berg's avatar
    wireless: regulatory: fix channel disabling race condition · 990de49f
    Johannes Berg authored
    When a full scan 2.4 and 5 GHz scan is scheduled, but then the 2.4 GHz
    part of the scan disables a 5.2 GHz channel due to, e.g. receiving
    country or frequency information, that 5.2 GHz channel might already
    be in the list of channels to scan next. Then, when the driver checks
    if it should do a passive scan, that will return false and attempt an
    active scan. This is not only wrong but can also lead to the iwlwifi
    device firmware crashing since it checks regulatory as well.
    Fix this by not setting the channel flags to just disabled but rather
    OR'ing in the disabled flag. That way, even if the race happens, the
    channel will be scanned passively which is still (mostly) correct.
    Cc: stable@vger.kernel.org
    Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
reg.c 63.9 KB