Update sprintf in serial_show frunction to scnprintf command to
prevent sysfs buffer overflow (buffer always is PAGE_SIZE bytes).

Signed-off-by: Viacheslav Bocharov <adeep@lexina.in>
---
 drivers/firmware/meson/meson_sm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/firmware/meson/meson_sm.c b/drivers/firmware/meson/meson_sm.c
index ed60f1103053..c1c694b485ee 100644
--- a/drivers/firmware/meson/meson_sm.c
+++ b/drivers/firmware/meson/meson_sm.c
@@ -265,7 +265,7 @@ static ssize_t serial_show(struct device *dev, struct device_attribute *attr,
 		return ret;
 	}
 
-	ret = sprintf(buf, "%12phN\n", &id_buf[SM_CHIP_ID_OFFSET]);
+	ret = scnprintf(buf, PAGE_SIZE, "%12phN\n", &id_buf[SM_CHIP_ID_OFFSET]);
 
 	kfree(id_buf);
 
-- 
2.34.1