s5h1420: fix a buffer overflow when checking userspace params

commit 12f4543f5d6811f864e6c4952eb27253c7466c02 upstream.

The maximum size for a DiSEqC command is 6, according to the
userspace API. However, the code allows to write up to 7 values:
	drivers/media/dvb-frontends/s5h1420.c:193 s5h1420_send_master_cmd() error: buffer overflow 'cmd->msg' 6 <= 7

Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
[bwh: Backported to 3.2: adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/drivers/media/dvb/frontends/s5h1420.c b/drivers/media/dvb/frontends/s5h1420.c
index 3879d2e..507ccae 100644 (file)
--- a/drivers/media/dvb/frontends/s5h1420.c
+++ b/drivers/media/dvb/frontends/s5h1420.c
@@ -180,7 +180,7 @@ static int s5h1420_send_master_cmd (struct dvb_frontend* fe,
        int result = 0;
 
        dprintk("enter %s\n", __func__);
-       if (cmd->msg_len > 8)
+       if (cmd->msg_len > sizeof(cmd->msg))
                return -EINVAL;
 
        /* setup for DISEQC */