diff --git a/drivers/media/dvb-frontends/stb6100.c b/drivers/media/dvb-frontends/stb6100.c
index cea175d198907..4ef8a5c7003e9 100644
--- a/drivers/media/dvb-frontends/stb6100.c
+++ b/drivers/media/dvb-frontends/stb6100.c
@@ -193,7 +193,7 @@ static int stb6100_write_reg_range(struct stb6100_state *state, u8 buf[], int st
 		.len	= len + 1
 	};
 
-	if (1 + len > sizeof(buf)) {
+	if (1 + len > sizeof(cmdbuf)) {
 		printk(KERN_WARNING
 		       "%s: i2c wr: len=%d is too big!\n",
 		       KBUILD_MODNAME, len);