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Sender: Guenter Roeck <groeck7@gmail.com>
Date:   Thu, 23 Sep 2021 18:06:04 -0700
From:   Guenter Roeck <linux@roeck-us.net>
To:     Colin King <colin.king@canonical.com>
Cc:     Jean Delvare <jdelvare@suse.com>,
        Vadim Pasternak <vadimp@nvidia.com>,
        linux-hwmon@vger.kernel.org, kernel-janitors@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH][next] hwmon: (mlxreg-fan): Fix out of bounds read on
 array fan->pwm
Message-ID: <20210924010604.GA3029410@roeck-us.net>
References: <20210920180921.16246-1-colin.king@canonical.com>
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On Mon, Sep 20, 2021 at 07:09:21PM +0100, Colin King wrote:
> From: Colin Ian King <colin.king@canonical.com>
> 
> Array fan->pwm[] is MLXREG_FAN_MAX_PWM elements in size, however the
> for-loop has a off-by-one error causing index i to be out of range
> causing an out of bounds read on the array. Fix this by replacing
> the <= operator with < in the for-loop.
> 
> Addresses-Coverity: ("Out-of-bounds read")
> Fixes: 35edbaab3bbf ("hwmon: (mlxreg-fan) Extend driver to support multiply cooling devices")
> Signed-off-by: Colin Ian King <colin.king@canonical.com>

Applied.

Thanks,
Guenter

> ---
>  drivers/hwmon/mlxreg-fan.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/hwmon/mlxreg-fan.c b/drivers/hwmon/mlxreg-fan.c
> index 35228ed112d7..feab9ec6a6ca 100644
> --- a/drivers/hwmon/mlxreg-fan.c
> +++ b/drivers/hwmon/mlxreg-fan.c
> @@ -554,7 +554,7 @@ static int mlxreg_fan_cooling_config(struct device *dev, struct mlxreg_fan *fan)
>  {
>  	int i, j;
>  
> -	for (i = 0; i <= MLXREG_FAN_MAX_PWM; i++) {
> +	for (i = 0; i < MLXREG_FAN_MAX_PWM; i++) {
>  		struct mlxreg_fan_pwm *pwm = &fan->pwm[i];
>  
>  		if (!pwm->connected)