linux-kernel - [PATCH 1/4] pwm: bcm-iproc: Remove impossible comparison when validating duty cycle

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 for Android: free password hash cracker in your pocket

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

Message-Id: <20200629124752.1018358-2-lee.jones@linaro.org>
Date:   Mon, 29 Jun 2020 13:47:49 +0100
From:   Lee Jones <lee.jones@...aro.org>
To:     thierry.reding@...il.com, u.kleine-koenig@...gutronix.de,
        linux-pwm@...r.kernel.org
Cc:     linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
        Lee Jones <lee.jones@...aro.org>, Ray Jui <rjui@...adcom.com>,
        Scott Branden <sbranden@...adcom.com>,
        Yendapally Reddy Dhananjaya Reddy 
        <yendapally.reddy@...adcom.com>,
        bcm-kernel-feedback-list@...adcom.com
Subject: [PATCH 1/4] pwm: bcm-iproc: Remove impossible comparison when validating duty cycle

'duty' here is an unsigned int, thus checking for <0 will always
evaluate to false.

Fixes the following W=1 warning:

 drivers/pwm/pwm-bcm-iproc.c:147:12: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits]

Cc: Ray Jui <rjui@...adcom.com>
Cc: Scott Branden <sbranden@...adcom.com>
Cc: Yendapally Reddy Dhananjaya Reddy <yendapally.reddy@...adcom.com>
Cc: bcm-kernel-feedback-list@...adcom.com
Cc: linux-pwm@...r.kernel.org
Signed-off-by: Lee Jones <lee.jones@...aro.org>
---
 drivers/pwm/pwm-bcm-iproc.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/pwm/pwm-bcm-iproc.c b/drivers/pwm/pwm-bcm-iproc.c
index 1f829edd8ee70..46f0a45e9049c 100644
--- a/drivers/pwm/pwm-bcm-iproc.c
+++ b/drivers/pwm/pwm-bcm-iproc.c
@@ -143,8 +143,7 @@ static int iproc_pwmc_apply(struct pwm_chip *chip, struct pwm_device *pwm,
 		value = rate * state->duty_cycle;
 		duty = div64_u64(value, div);
 
-		if (period < IPROC_PWM_PERIOD_MIN ||
-		    duty < IPROC_PWM_DUTY_CYCLE_MIN)
+		if (period < IPROC_PWM_PERIOD_MIN)
 			return -EINVAL;
 
 		if (period <= IPROC_PWM_PERIOD_MAX &&
-- 
2.25.1