lkml.org 
[lkml]   [2016]   [Aug]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH] leds: do not overflow sysfs buffer in led_trigger_show
From
Date
Hi Zach,

On 08/16/2016 12:20 AM, Zach Brown wrote:
> From: Nathan Sullivan <nathan.sullivan@ni.com>
>
> Per the documentation, use scnprintf instead of sprintf to ensure there
> is never more than PAGE_SIZE bytes of trigger names put into the
> buffer.
>
> Signed-off-by: Nathan Sullivan <nathan.sullivan@ni.com>
> Signed-off-by: Zach Brown <zach.brown@ni.com>
> ---
> drivers/leds/led-triggers.c | 12 +++++++-----
> 1 file changed, 7 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/leds/led-triggers.c b/drivers/leds/led-triggers.c
> index c92702a..8668538 100644
> --- a/drivers/leds/led-triggers.c
> +++ b/drivers/leds/led-triggers.c
> @@ -81,21 +81,23 @@ ssize_t led_trigger_show(struct device *dev, struct device_attribute *attr,
> down_read(&led_cdev->trigger_lock);
>
> if (!led_cdev->trigger)
> - len += sprintf(buf+len, "[none] ");
> + len += scnprintf(buf+len, PAGE_SIZE - len, "[none] ");
> else
> - len += sprintf(buf+len, "none ");
> + len += scnprintf(buf+len, PAGE_SIZE - len, "none ");
>
> list_for_each_entry(trig, &trigger_list, next_trig) {
> if (led_cdev->trigger && !strcmp(led_cdev->trigger->name,
> trig->name))
> - len += sprintf(buf+len, "[%s] ", trig->name);
> + len += scnprintf(buf+len, PAGE_SIZE - len, "[%s] ",
> + trig->name);
> else
> - len += sprintf(buf+len, "%s ", trig->name);
> + len += scnprintf(buf+len, PAGE_SIZE - len, "%s ",
> + trig->name);
> }
> up_read(&led_cdev->trigger_lock);
> up_read(&triggers_list_lock);
>
> - len += sprintf(len+buf, "\n");
> + len += scnprintf(len+buf, PAGE_SIZE - len, "\n");
> return len;
> }
> EXPORT_SYMBOL_GPL(led_trigger_show);
>

Thanks for the patch, applied.

--
Best regards,
Jacek Anaszewski

\
 
 \ /
  Last update: 2016-09-17 09:57    [W:0.094 / U:0.180 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site