Commit ec649fed authored Oct 21, 2019 by Masashi Honma Committed by Johannes Berg Oct 30, 2019

nl80211: Disallow setting of HT for channel 14



This patch disables setting of HT20 and more for channel 14 because
the channel is only for IEEE 802.11b.

The patch for net/wireless/util.c was unit-tested.

The patch for net/wireless/chan.c was tested with iw command.

Before this patch.
$ sudo iw dev <ifname> set channel 14 HT20
$

After this patch.
$ sudo iw dev <ifname> set channel 14 HT20
kernel reports: invalid channel definition
command failed: Invalid argument (-22)
$

Signed-off-by: Masashi Honma <masashi.honma@gmail.com>
Link: https://lore.kernel.org/r/20191021075045.2719-1-masashi.honma@gmail.com


[clean up the code, use != instead of equivalent >]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

parent 6f74a55d

net/wireless/chan.c

+5 −0

Original line number	Diff line number	Diff line
		@@ -204,6 +204,11 @@ bool cfg80211_chandef_valid(const struct cfg80211_chan_def *chandef)
		return false;
		}

		/* channel 14 is only for IEEE 802.11b */
		if (chandef->center_freq1 == 2484 &&
		chandef->width != NL80211_CHAN_WIDTH_20_NOHT)
		return false;

		if (cfg80211_chandef_is_edmg(chandef) &&
		!cfg80211_edmg_chandef_valid(chandef))
		return false;

net/wireless/util.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -1559,7 +1559,8 @@ bool ieee80211_chandef_to_operating_class(struct cfg80211_chan_def *chandef,
		}

		if (freq == 2484) {
		if (chandef->width > NL80211_CHAN_WIDTH_40)
		/* channel 14 is only for IEEE 802.11b */
		if (chandef->width != NL80211_CHAN_WIDTH_20_NOHT)
		return false;

		op_class = 82; / channel 14 */

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