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| author | Mauro Carvalho Chehab <m.chehab@samsung.com> | 2013-11-02 10:18:09 (GMT) |
|---|---|---|
| committer | Mauro Carvalho Chehab <m.chehab@samsung.com> | 2013-11-08 11:45:43 (GMT) |
| commit | 64f7ef8afbf89f3c72c4d2472e4914ca198c0668 (patch) | |
| tree | 5448f49c48d04f831632a09511e922cf82283a9d /drivers/media/usb | |
| parent | 24e9a47e14f0a97ee97abc3dd86b2ef254448a17 (diff) | |
| download | linux-fsl-qoriq-64f7ef8afbf89f3c72c4d2472e4914ca198c0668.tar.xz | |
[media] cxusb: Don't use dynamic static allocation
Dynamic static allocation is evil, as Kernel stack is too low, and
compilation complains about it on some archs:
drivers/media/usb/dvb-usb/cxusb.c:209:1: warning: 'cxusb_i2c_xfer' uses dynamic stack allocation [enabled by default]
drivers/media/usb/dvb-usb/cxusb.c:69:1: warning: 'cxusb_ctrl_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>
Diffstat (limited to 'drivers/media/usb')
| -rw-r--r-- | drivers/media/usb/dvb-usb/cxusb.c | 41 |
1 files changed, 37 insertions, 4 deletions
diff --git a/drivers/media/usb/dvb-usb/cxusb.c b/drivers/media/usb/dvb-usb/cxusb.c index 3940bb0..20e345d 100644 --- a/drivers/media/usb/dvb-usb/cxusb.c +++ b/drivers/media/usb/dvb-usb/cxusb.c @@ -43,6 +43,9 @@ #include "lgs8gxx.h" #include "atbm8830.h" +/* Max transfer size done by I2C transfer functions */ +#define MAX_XFER_SIZE 64 + /* debug */ static int dvb_usb_cxusb_debug; module_param_named(debug, dvb_usb_cxusb_debug, int, 0644); @@ -57,7 +60,14 @@ static int cxusb_ctrl_msg(struct dvb_usb_device *d, u8 cmd, u8 *wbuf, int wlen, u8 *rbuf, int rlen) { int wo = (rbuf == NULL || rlen == 0); /* write-only */ - u8 sndbuf[1+wlen]; + u8 sndbuf[MAX_XFER_SIZE]; + + if (1 + wlen > sizeof(sndbuf)) { + warn("i2c wr: len=%d is too big!\n", + wlen); + return -EOPNOTSUPP; + } + memset(sndbuf, 0, 1+wlen); sndbuf[0] = cmd; @@ -158,7 +168,13 @@ static int cxusb_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msg[], if (msg[i].flags & I2C_M_RD) { /* read only */ - u8 obuf[3], ibuf[1+msg[i].len]; + u8 obuf[3], ibuf[MAX_XFER_SIZE]; + + if (1 + msg[i].len > sizeof(ibuf)) { + warn("i2c rd: len=%d is too big!\n", + msg[i].len); + return -EOPNOTSUPP; + } obuf[0] = 0; obuf[1] = msg[i].len; obuf[2] = msg[i].addr; @@ -172,7 +188,18 @@ static int cxusb_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msg[], } else if (i+1 < num && (msg[i+1].flags & I2C_M_RD) && msg[i].addr == msg[i+1].addr) { /* write to then read from same address */ - u8 obuf[3+msg[i].len], ibuf[1+msg[i+1].len]; + u8 obuf[MAX_XFER_SIZE], ibuf[MAX_XFER_SIZE]; + + if (3 + msg[i].len > sizeof(obuf)) { + warn("i2c wr: len=%d is too big!\n", + msg[i].len); + return -EOPNOTSUPP; + } + if (1 + msg[i + 1].len > sizeof(ibuf)) { + warn("i2c rd: len=%d is too big!\n", + msg[i + 1].len); + return -EOPNOTSUPP; + } obuf[0] = msg[i].len; obuf[1] = msg[i+1].len; obuf[2] = msg[i].addr; @@ -191,7 +218,13 @@ static int cxusb_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msg[], i++; } else { /* write only */ - u8 obuf[2+msg[i].len], ibuf; + u8 obuf[MAX_XFER_SIZE], ibuf; + + if (2 + msg[i].len > sizeof(obuf)) { + warn("i2c wr: len=%d is too big!\n", + msg[i].len); + return -EOPNOTSUPP; + } obuf[0] = msg[i].addr; obuf[1] = msg[i].len; memcpy(&obuf[2], msg[i].buf, msg[i].len); |