| From: Nathan Sullivan <nathan.sullivan@ni.com> |
| Date: Mon, 15 Aug 2016 17:20:14 -0500 |
| Subject: leds: do not overflow sysfs buffer in led_trigger_show |
| |
| commit 3b9b95363c45365d606ad4bbba16acca75fdf6d3 upstream. |
| |
| 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> |
| Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com> |
| Cc: Vlastimil Babka <vbabka@suse.cz> |
| Signed-off-by: Ben Hutchings <ben@decadent.org.uk> |
| --- |
| drivers/leds/led-triggers.c | 12 +++++++----- |
| 1 file changed, 7 insertions(+), 5 deletions(-) |
| |
| --- a/drivers/leds/led-triggers.c |
| +++ b/drivers/leds/led-triggers.c |
| @@ -78,21 +78,23 @@ ssize_t led_trigger_show(struct device * |
| 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); |