diff options
| author | Mauro Carvalho Chehab <m.chehab@samsung.com> | 2013-11-02 07:23:49 -0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-12-04 10:57:31 -0800 |
| commit | 7ce9cdbe07651a2417a00d0a37c8b9fefae12f4b (patch) | |
| tree | ff3fd0633bcfe13e5f0bc8171df72bcae396d551 | |
| parent | b49dfbeea93ebd078fa57404913d7e89320e94fa (diff) | |
media: dibusb-common: Don't use dynamic static allocation
commit 1d7fa359d4c0fbb2756fa01cc47212908d90b7b0 upstream.
Dynamic static allocation is evil, as Kernel stack is too low, and
compilation complains about it on some archs:
drivers/media/usb/dvb-usb/dibusb-common.c:124:1: warning: 'dibusb_i2c_msg' uses dynamic stack allocation [enabled by default]
Instead, let's enforce a limit for the buffer to be the max size of
a control URB payload data (64 bytes).
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
Reviewed-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -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 c2dded92f1d..6d68af0c49c 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); |