Commit 8442938c authored Aug 31, 2018 by Dan Carpenter Committed by Johannes Berg Sep 03, 2018

cfg80211: fix a type issue in ieee80211_chandef_to_operating_class()



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
9cf0a0b4 ("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@oracle.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

parent 66eb02d8

net/wireless/util.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -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)

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