[media] rtl2832_sdr: do not use dynamic stack allocation

Do not use dynamic stack allocation.

>> drivers/staging/media/rtl2832u_sdr/rtl2832_sdr.c:181:1:
warning: 'rtl2832_sdr_wr' uses dynamic stack allocation [enabled by default]

Reported-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

diff --git a/drivers/staging/media/rtl2832u_sdr/rtl2832_sdr.c b/drivers/staging/media/rtl2832u_sdr/rtl2832_sdr.c
index b09f7d8c12cf8faf3dfbc844bd13f8d88fa82196..104ee8af79af1f138c2300e3efe9fa9cf3972f29 100644 (file)
--- a/drivers/staging/media/rtl2832u_sdr/rtl2832_sdr.c
+++ b/drivers/staging/media/rtl2832u_sdr/rtl2832_sdr.c
@@ -156,7 +156,9 @@ static int rtl2832_sdr_wr(struct rtl2832_sdr_state *s, u8 reg, const u8 *val,
                int len)
 {
        int ret;
-       u8 buf[1 + len];
+#define MAX_WR_LEN 24
+#define MAX_WR_XFER_LEN (MAX_WR_LEN + 1)
+       u8 buf[MAX_WR_XFER_LEN];
        struct i2c_msg msg[1] = {
                {
                        .addr = s->cfg->i2c_addr,
@@ -166,6 +168,9 @@ static int rtl2832_sdr_wr(struct rtl2832_sdr_state *s, u8 reg, const u8 *val,
                }
        };
 
+       if (WARN_ON(len > MAX_WR_LEN))
+               return -EINVAL;
+
        buf[0] = reg;
        memcpy(&buf[1], val, len);