[PATCH] leds: do not overflow sysfs buffer in led_trigger_show
From: Zach Brown <hidden>
Date: 2016-08-15 22:39:38
Also in:
lkml
Subsystem:
led subsystem, the rest · Maintainers:
Lee Jones, Pavel Machek, Linus Torvalds
From: Nathan Sullivan <redacted> 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 <redacted> Signed-off-by: Zach Brown <redacted> --- 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);
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2.7.4