[PATCH 5.4 51/90] wireless: fix enabling channel 12 for custom regulatory domain

Greg Kroah-Hartman
2020-02-03T16:40:49Z

From: Ganapathi Bhat <ganapathi.bhat@nxp.com>

[ Upstream commit c4b9d655e445a8be0bff624aedea190606b5ebbc ]

Commit e33e2241e272 ("Revert "cfg80211: Use 5MHz bandwidth by
default when checking usable channels"") fixed a broken
regulatory (leaving channel 12 open for AP where not permitted).
Apply a similar fix to custom regulatory domain processing.

Signed-off-by: Cathy Luo <xiaohua.luo@nxp.com>
Signed-off-by: Ganapathi Bhat <ganapathi.bhat@nxp.com>
Link: https://lore.kernel.org/r/1576836859-8945-1-git-send-email-ganapathi.bhat@nxp.com
[reword commit message, fix coding style, add a comment]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
net/wireless/reg.c | 13 ++++++++++---
1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/net/wireless/reg.c b/net/wireless/reg.c
index 446c76d44e65a..3c2070040277d 100644
--- a/net/wireless/reg.c
+++ b/net/wireless/reg.c
@@ -2261,14 +2261,15 @@ static void update_all_wiphy_regulatory(enum nl80211_reg_initiator initiator)

static void handle_channel_custom(struct wiphy *wiphy,
struct ieee80211_channel *chan,
- const struct ieee80211_regdomain *regd)
+ const struct ieee80211_regdomain *regd,
+ u32 min_bw)
{
u32 bw_flags = 0;
const struct ieee80211_reg_rule *reg_rule = NULL;
const struct ieee80211_power_rule *power_rule = NULL;
u32 bw;

- for (bw = MHZ_TO_KHZ(20); bw >= MHZ_TO_KHZ(5); bw = bw / 2) {
+ for (bw = MHZ_TO_KHZ(20); bw >= min_bw; bw = bw / 2) {
reg_rule = freq_reg_info_regd(MHZ_TO_KHZ(chan->center_freq),
regd, bw);
if (!IS_ERR(reg_rule))
@@ -2324,8 +2325,14 @@ static void handle_band_custom(struct wiphy *wiphy,
if (!sband)
return;

+ /*
+ * We currently assume that you always want at least 20 MHz,
+ * otherwise channel 12 might get enabled if this rule is
+ * compatible to US, which permits 2402 - 2472 MHz.
+ */
for (i = 0; i < sband->n_channels; i++)
- handle_channel_custom(wiphy, &sband->channels[i], regd);
+ handle_channel_custom(wiphy, &sband->channels[i], regd,
+ MHZ_TO_KHZ(20));
}

/* Used by drivers prior to wiphy registration */
--
2.20.1