linux-kernel - [PATCH 3.18 08/90] net: qla3xxx: Remove overflowing shift statement

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20181119162622.136033534@linuxfoundation.org>
Date:   Mon, 19 Nov 2018 17:28:50 +0100
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org,
        Nathan Chancellor <natechancellor@...il.com>,
        "David S. Miller" <davem@...emloft.net>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 3.18 08/90] net: qla3xxx: Remove overflowing shift statement

3.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Nathan Chancellor <natechancellor@...il.com>

[ Upstream commit 8c3bf9b62b667456a57aefcf1689e826df146159 ]

Clang currently warns:

drivers/net/ethernet/qlogic/qla3xxx.c:384:24: warning: signed shift
result (0xF00000000) requires 37 bits to represent, but 'int' only has
32 bits [-Wshift-overflow]
                    ((ISP_NVRAM_MASK << 16) | qdev->eeprom_cmd_data));
                      ~~~~~~~~~~~~~~ ^  ~~
1 warning generated.

The warning is certainly accurate since ISP_NVRAM_MASK is defined as
(0x000F << 16) which is then shifted by 16, resulting in 64424509440,
well above UINT_MAX.

Given that this is the only location in this driver where ISP_NVRAM_MASK
is shifted again, it seems likely that ISP_NVRAM_MASK was originally
defined without a shift and during the move of the shift to the
definition, this statement wasn't properly removed (since ISP_NVRAM_MASK
is used in the statenent right above this). Only the maintainers can
confirm this since this statment has been here since the driver was
first added to the kernel.

Link: https://github.com/ClangBuiltLinux/linux/issues/127
Signed-off-by: Nathan Chancellor <natechancellor@...il.com>
Signed-off-by: David S. Miller <davem@...emloft.net>
Signed-off-by: Sasha Levin <sashal@...nel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
---
 drivers/net/ethernet/qlogic/qla3xxx.c |    2 --
 1 file changed, 2 deletions(-)

--- a/drivers/net/ethernet/qlogic/qla3xxx.c
+++ b/drivers/net/ethernet/qlogic/qla3xxx.c
@@ -382,8 +382,6 @@ static void fm93c56a_select(struct ql3_a
 
 	qdev->eeprom_cmd_data = AUBURN_EEPROM_CS_1;
 	ql_write_nvram_reg(qdev, spir, ISP_NVRAM_MASK | qdev->eeprom_cmd_data);
-	ql_write_nvram_reg(qdev, spir,
-			   ((ISP_NVRAM_MASK << 16) | qdev->eeprom_cmd_data));
 }
 
 /*