From 3443c54c41718f9aa4785e0388dce7ccddffaac7 Mon Sep 17 00:00:00 2001 From: Colin Ian King Date: Thu, 25 Feb 2021 18:32:41 +0000 Subject: [PATCH] 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 Acked-by: Jakub Kicinski Signed-off-by: Kalle Valo Link: https://lore.kernel.org/r/20210225183241.1002129-1-colin.king@canonical.com Signed-off-by: Sasha Levin --- drivers/net/wireless/mediatek/mt7601u/eeprom.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/wireless/mediatek/mt7601u/eeprom.c b/drivers/net/wireless/mediatek/mt7601u/eeprom.c index c868582..aa3b649 100644 --- a/drivers/net/wireless/mediatek/mt7601u/eeprom.c +++ b/drivers/net/wireless/mediatek/mt7601u/eeprom.c @@ -99,7 +99,7 @@ mt7601u_has_tssi(struct mt7601u_dev *dev, u8 *eeprom) { u16 nic_conf1 = get_unaligned_le16(eeprom + MT_EE_NIC_CONF_1); - return ~nic_conf1 && (nic_conf1 & MT_EE_NIC_CONF_1_TX_ALC_EN); + return (u16)~nic_conf1 && (nic_conf1 & MT_EE_NIC_CONF_1_TX_ALC_EN); } static void -- 2.7.4