[media] horus3a: don't use variable length arrays

The Linux stack is short; we need to be able to count the number
of bytes used at stack on each function. So, we don't like to
use variable-length arrays, as complained by smatch:
	drivers/media/dvb-frontends/horus3a.c:57:19: warning: Variable length array is used.

The max usecase of the driver seems to be 5 bytes + 1 for the
register.

So, let's be safe and allocate 6 bytes for the write buffer.
This should be enough to cover all cases. If not, let's print
an error message.

Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
This commit is contained in:
Mauro Carvalho Chehab 2015-08-11 15:29:54 -03:00
parent d13a7b674a
commit 4aabd91625

View File

@ -26,6 +26,8 @@
#include "horus3a.h"
#include "dvb_frontend.h"
#define MAX_WRITE_REGSIZE 5
enum horus3a_state {
STATE_UNKNOWN,
STATE_SLEEP,
@ -54,16 +56,22 @@ static int horus3a_write_regs(struct horus3a_priv *priv,
u8 reg, const u8 *data, u32 len)
{
int ret;
u8 buf[len+1];
u8 buf[MAX_WRITE_REGSIZE + 1];
struct i2c_msg msg[1] = {
{
.addr = priv->i2c_address,
.flags = 0,
.len = sizeof(buf),
.len = len + 1,
.buf = buf,
}
};
if (len + 1 >= sizeof(buf)) {
dev_warn(&priv->i2c->dev,"wr reg=%04x: len=%d is too big!\n",
reg, len + 1);
return -E2BIG;
}
horus3a_i2c_debug(priv, reg, 1, data, len);
buf[0] = reg;
memcpy(&buf[1], data, len);