[PATCH] drm: sysfs: Use scnprintf() for avoiding potential buffer overflow

[Takashi Iwai]

Since snprintf() returns the would-be-output size instead of the
actual output size, the succeeding calls may go beyond the given
buffer limit.  Fix it by replacing with scnprintf().

Signed-off-by: Takashi Iwai <tiwai at suse.de>
---
 drivers/gpu/drm/drm_sysfs.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/drm_sysfs.c b/drivers/gpu/drm/drm_sysfs.c
index dd2bc85f43cc..9b3180e8c12f 100644
--- a/drivers/gpu/drm/drm_sysfs.c
+++ b/drivers/gpu/drm/drm_sysfs.c
@@ -230,7 +230,7 @@ static ssize_t modes_show(struct device *device,
 
 	mutex_lock(&connector->dev->mode_config.mutex);
 	list_for_each_entry(mode, &connector->modes, head) {
-		written += snprintf(buf + written, PAGE_SIZE - written, "%s\n",
+		written += scnprintf(buf + written, PAGE_SIZE - written, "%s\n",
 				    mode->name);
 	}
 	mutex_unlock(&connector->dev->mode_config.mutex);
-- 
2.16.4