mt7601u: fix always true expression
authorColin Ian King <colin.king@canonical.com>
Thu, 25 Feb 2021 18:32:41 +0000 (18:32 +0000)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 14 May 2021 07:50:34 +0000 (09:50 +0200)
commit3443c54c41718f9aa4785e0388dce7ccddffaac7
tree21c402b92d3bba12350afc578ee69d1db63db6be
parent00792f31a330cb5da7ae35dba6a2e9d8c6211c83
mt7601u: fix always true expression

[ Upstream commit 87fce88658ba047ae62e83497d3f3c5dc22fa6f9 ]

Currently the expression ~nic_conf1 is always true because nic_conf1
is a u16 and according to 6.5.3.3 of the C standard the ~ operator
promotes the u16 to an integer before flipping all the bits. Thus
the top 16 bits of the integer result are all set so the expression
is always true.  If the intention was to flip all the bits of nic_conf1
then casting the integer result back to a u16 is a suitabel fix.

Interestingly static analyzers seem to thing a bitwise ! should be
used instead of ~ for this scenario, so I think the original intent
of the expression may need some extra consideration.

Addresses-Coverity: ("Logical vs. bitwise operator")
Fixes: c869f77d6abb ("add mt7601u driver")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Jakub Kicinski <kubakici@wp.pl>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20210225183241.1002129-1-colin.king@canonical.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
drivers/net/wireless/mediatek/mt7601u/eeprom.c