diff options
Diffstat (limited to 'drivers/media/usb/dvb-usb/dibusb-common.c')
-rw-r--r-- | drivers/media/usb/dvb-usb/dibusb-common.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/drivers/media/usb/dvb-usb/dibusb-common.c b/drivers/media/usb/dvb-usb/dibusb-common.c index c2dded9..6d68af0 100644 --- a/drivers/media/usb/dvb-usb/dibusb-common.c +++ b/drivers/media/usb/dvb-usb/dibusb-common.c @@ -12,6 +12,9 @@ #include <linux/kconfig.h> #include "dibusb.h" +/* Max transfer size done by I2C transfer functions */ +#define MAX_XFER_SIZE 64 + static int debug; module_param(debug, int, 0644); MODULE_PARM_DESC(debug, "set debugging level (1=info (|-able))." DVB_USB_DEBUG_STATUS); @@ -105,11 +108,16 @@ EXPORT_SYMBOL(dibusb2_0_power_ctrl); static int dibusb_i2c_msg(struct dvb_usb_device *d, u8 addr, u8 *wbuf, u16 wlen, u8 *rbuf, u16 rlen) { - u8 sndbuf[wlen+4]; /* lead(1) devaddr,direction(1) addr(2) data(wlen) (len(2) (when reading)) */ + u8 sndbuf[MAX_XFER_SIZE]; /* lead(1) devaddr,direction(1) addr(2) data(wlen) (len(2) (when reading)) */ /* write only ? */ int wo = (rbuf == NULL || rlen == 0), len = 2 + wlen + (wo ? 0 : 2); + if (4 + wlen > sizeof(sndbuf)) { + warn("i2c wr: len=%d is too big!\n", wlen); + return -EOPNOTSUPP; + } + sndbuf[0] = wo ? DIBUSB_REQ_I2C_WRITE : DIBUSB_REQ_I2C_READ; sndbuf[1] = (addr << 1) | (wo ? 0 : 1); |