From ec649fed66bb242cca145ab364485c5a126efc53 Mon Sep 17 00:00:00 2001 From: Masashi Honma Date: Mon, 21 Oct 2019 16:50:45 +0900 Subject: [PATCH] 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 set channel 14 HT20 $ After this patch. $ sudo iw dev set channel 14 HT20 kernel reports: invalid channel definition command failed: Invalid argument (-22) $ Signed-off-by: Masashi Honma 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 --- net/wireless/chan.c | 5 +++++ net/wireless/util.c | 3 ++- 2 files changed, 7 insertions(+), 1 deletion(-) diff --git a/net/wireless/chan.c b/net/wireless/chan.c index e851cafd8e2f..fcac5c6366e1 100644 --- a/net/wireless/chan.c +++ b/net/wireless/chan.c @@ -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; diff --git a/net/wireless/util.c b/net/wireless/util.c index 419eb12c1e93..5b4ed5bbc542 100644 --- a/net/wireless/util.c +++ b/net/wireless/util.c @@ -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 */