Wireless access point daemon, patched with ubus support
c4dd3afa3c
When the channel time is zero the interference factor calculation falls under divide by zero operation which results in invalid (NaN = not-a-number) interference factor value. This leads to wrong ideal channel selection in ACS during the scenario described below. Scenario: In VHT80 mode, the channel 36 (first channel) gets the channel time as zero which causes the interfactor factor to be an invalid number (NaN). Any operations (like addition, mulitplication, divide, etc.) with NaN value results in a NaN value, so that average factor for the primary channel 36 got the invalid value (NaN). Since channel 36 is the first channel, ideal factor is assigned as NaN in the first iteration. The following iteration condition check (factor < ideal_factor) with a NaN value fail for all other primary channels. This results in channel 36 being chosen as the ideal channel in ACS which holds a NaN value. Logs: ACS: Survey analysis for channel 36 (5180 MHz) ACS: 1: min_nf=-103 interference_factor=nan nf=0 time=0 busy=0 rx=0 ACS: 2: min_nf=-103 interference_factor=0.615385 nf=-102 time=13 busy=8 rx=0 ACS: 3: min_nf=-103 interference_factor=2.45455 nf=0 time=22 busy=16 rx=0 ACS: 4: min_nf=-103 interference_factor=0.785714 nf=-103 time=42 busy=33 rx=0 ACS: 5: min_nf=-103 interference_factor=nan nf=0 time=0 busy=0 rx=0 ACS: * interference factor average: nan ... ACS: * channel 36: total interference = nan .. ACS: * channel 149: total interference = 5.93174e-21 .. ACS: Ideal channel is 36 (5180 MHz) with total interference factor of nan Signed-off-by: Karthikeyan Periyasamy <periyasa@codeaurora.org> |
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| doc | ||
| eap_example | ||
| hostapd | ||
| hs20 | ||
| mac80211_hwsim/tools | ||
| radius_example | ||
| src | ||
| tests | ||
| wlantest | ||
| wpa_supplicant | ||
| wpadebug | ||
| wpaspy | ||
| .gitignore | ||
| Android.mk | ||
| build_release | ||
| CONTRIBUTIONS | ||
| COPYING | ||
| README | ||
wpa_supplicant and hostapd -------------------------- Copyright (c) 2002-2017, Jouni Malinen <j@w1.fi> and contributors All Rights Reserved. These programs are licensed under the BSD license (the one with advertisement clause removed). If you are submitting changes to the project, please see CONTRIBUTIONS file for more instructions. This package may include either wpa_supplicant, hostapd, or both. See README file respective subdirectories (wpa_supplicant/README or hostapd/README) for more details. Source code files were moved around in v0.6.x releases and compared to earlier releases, the programs are now built by first going to a subdirectory (wpa_supplicant or hostapd) and creating build configuration (.config) and running 'make' there (for Linux/BSD/cygwin builds). License ------- This software may be distributed, used, and modified under the terms of BSD license: Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. 3. Neither the name(s) of the above-listed copyright holder(s) nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.