From: Dan Carpenter <dan.carpenter@xxxxxxxxxx> [ Upstream commit 8442938c3a2177ba16043b3a935f2c78266ad399 ] The "chandef->center_freq1" variable is a u32 but "freq" is a u16 so we are truncating away the high bits. I noticed this bug because in commit 9cf0a0b4b64a ("cfg80211: Add support for 60GHz band channels 5 and 6") we made "freq <= 56160 + 2160 * 6" a valid requency when before it was only "freq <= 56160 + 2160 * 4" that was valid. It introduces a static checker warning: net/wireless/util.c:1571 ieee80211_chandef_to_operating_class() warn: always true condition '(freq <= 56160 + 2160 * 6) => (0-u16max <= 69120)' But really we probably shouldn't have been truncating the high bits away to begin with. Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx> --- net/wireless/util.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/wireless/util.c b/net/wireless/util.c index 3c654cd7ba56..908bf5b6d89e 100644 --- a/net/wireless/util.c +++ b/net/wireless/util.c @@ -1374,7 +1374,7 @@ bool ieee80211_chandef_to_operating_class(struct cfg80211_chan_def *chandef, u8 *op_class) { u8 vht_opclass; - u16 freq = chandef->center_freq1; + u32 freq = chandef->center_freq1; if (freq >= 2412 && freq <= 2472) { if (chandef->width > NL80211_CHAN_WIDTH_40) -- 2.17.1