Home Home > GIT Browse
summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorMauro Carvalho Chehab <m.chehab@samsung.com>2013-11-02 06:07:42 -0300
committerMauro Carvalho Chehab <m.chehab@samsung.com>2013-11-08 09:45:41 -0200
commitf1baab870f6e93b668af7b34d6f6ba49f1b0e982 (patch)
tree62a6301fb05795e0f849eb61925cd2e4492d0553
parent5bf30b3bc4ff80ef71a733a1f459cca4fa507892 (diff)
[media] tuners: 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/tuners/e4000.c:50:1: warning: 'e4000_wr_regs' uses dynamic stack allocation [enabled by default] drivers/media/tuners/e4000.c:83:1: warning: 'e4000_rd_regs' uses dynamic stack allocation [enabled by default] drivers/media/tuners/fc2580.c:66:1: warning: 'fc2580_wr_regs.constprop.1' uses dynamic stack allocation [enabled by default] drivers/media/tuners/fc2580.c:98:1: warning: 'fc2580_rd_regs.constprop.0' uses dynamic stack allocation [enabled by default] drivers/media/tuners/tda18212.c:57:1: warning: 'tda18212_wr_regs' uses dynamic stack allocation [enabled by default] drivers/media/tuners/tda18212.c:90:1: warning: 'tda18212_rd_regs.constprop.0' uses dynamic stack allocation [enabled by default] drivers/media/tuners/tda18218.c:60:1: warning: 'tda18218_wr_regs' uses dynamic stack allocation [enabled by default] drivers/media/tuners/tda18218.c:92:1: warning: 'tda18218_rd_regs.constprop.0' uses dynamic stack allocation [enabled by default] Instead, let's enforce a limit for the buffer. Considering that I2C transfers are generally limited, and that devices used on USB has a max data length of 64 bytes for the control URBs. So, it seem safe to use 64 bytes as the hard limit for all those devices. On most cases, the limit is a way lower than that, but this limit is small enough to not affect the Kernel stack, and it is a no brain limit, as using smaller ones would require to either carefully each driver or to take a look on each datasheet. Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com> Reviewed-by: Hans Verkuil <hans.verkuil@cisco.com> Reviewed-by: Antti Palosaari <crope@iki.fi> Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
-rw-r--r--drivers/media/tuners/e4000.c25
-rw-r--r--drivers/media/tuners/fc2580.c25
-rw-r--r--drivers/media/tuners/tda18212.c25
-rw-r--r--drivers/media/tuners/tda18218.c23
4 files changed, 83 insertions, 15 deletions
diff --git a/drivers/media/tuners/e4000.c b/drivers/media/tuners/e4000.c
index ad9309da4a91..c9cc1232f2e5 100644
--- a/drivers/media/tuners/e4000.c
+++ b/drivers/media/tuners/e4000.c
@@ -20,20 +20,30 @@
#include "e4000_priv.h"
+/* Max transfer size done by I2C transfer functions */
+#define MAX_XFER_SIZE 64
+
/* write multiple registers */
static int e4000_wr_regs(struct e4000_priv *priv, u8 reg, u8 *val, int len)
{
int ret;
- u8 buf[1 + len];
+ u8 buf[MAX_XFER_SIZE];
struct i2c_msg msg[1] = {
{
.addr = priv->cfg->i2c_addr,
.flags = 0,
- .len = sizeof(buf),
+ .len = 1 + len,
.buf = buf,
}
};
+ if (1 + len > sizeof(buf)) {
+ dev_warn(&priv->i2c->dev,
+ "%s: i2c wr reg=%04x: len=%d is too big!\n",
+ KBUILD_MODNAME, reg, len);
+ return -EINVAL;
+ }
+
buf[0] = reg;
memcpy(&buf[1], val, len);
@@ -53,7 +63,7 @@ static int e4000_wr_regs(struct e4000_priv *priv, u8 reg, u8 *val, int len)
static int e4000_rd_regs(struct e4000_priv *priv, u8 reg, u8 *val, int len)
{
int ret;
- u8 buf[len];
+ u8 buf[MAX_XFER_SIZE];
struct i2c_msg msg[2] = {
{
.addr = priv->cfg->i2c_addr,
@@ -63,11 +73,18 @@ static int e4000_rd_regs(struct e4000_priv *priv, u8 reg, u8 *val, int len)
}, {
.addr = priv->cfg->i2c_addr,
.flags = I2C_M_RD,
- .len = sizeof(buf),
+ .len = len,
.buf = buf,
}
};
+ if (len > sizeof(buf)) {
+ dev_warn(&priv->i2c->dev,
+ "%s: i2c rd reg=%04x: len=%d is too big!\n",
+ KBUILD_MODNAME, reg, len);
+ return -EINVAL;
+ }
+
ret = i2c_transfer(priv->i2c, msg, 2);
if (ret == 2) {
memcpy(val, buf, len);
diff --git a/drivers/media/tuners/fc2580.c b/drivers/media/tuners/fc2580.c
index 81f38aae9c66..3aecaf465094 100644
--- a/drivers/media/tuners/fc2580.c
+++ b/drivers/media/tuners/fc2580.c
@@ -20,6 +20,9 @@
#include "fc2580_priv.h"
+/* Max transfer size done by I2C transfer functions */
+#define MAX_XFER_SIZE 64
+
/*
* TODO:
* I2C write and read works only for one single register. Multiple registers
@@ -41,16 +44,23 @@
static int fc2580_wr_regs(struct fc2580_priv *priv, u8 reg, u8 *val, int len)
{
int ret;
- u8 buf[1 + len];
+ u8 buf[MAX_XFER_SIZE];
struct i2c_msg msg[1] = {
{
.addr = priv->cfg->i2c_addr,
.flags = 0,
- .len = sizeof(buf),
+ .len = 1 + len,
.buf = buf,
}
};
+ if (1 + len > sizeof(buf)) {
+ dev_warn(&priv->i2c->dev,
+ "%s: i2c wr reg=%04x: len=%d is too big!\n",
+ KBUILD_MODNAME, reg, len);
+ return -EINVAL;
+ }
+
buf[0] = reg;
memcpy(&buf[1], val, len);
@@ -69,7 +79,7 @@ static int fc2580_wr_regs(struct fc2580_priv *priv, u8 reg, u8 *val, int len)
static int fc2580_rd_regs(struct fc2580_priv *priv, u8 reg, u8 *val, int len)
{
int ret;
- u8 buf[len];
+ u8 buf[MAX_XFER_SIZE];
struct i2c_msg msg[2] = {
{
.addr = priv->cfg->i2c_addr,
@@ -79,11 +89,18 @@ static int fc2580_rd_regs(struct fc2580_priv *priv, u8 reg, u8 *val, int len)
}, {
.addr = priv->cfg->i2c_addr,
.flags = I2C_M_RD,
- .len = sizeof(buf),
+ .len = len,
.buf = buf,
}
};
+ if (len > sizeof(buf)) {
+ dev_warn(&priv->i2c->dev,
+ "%s: i2c rd reg=%04x: len=%d is too big!\n",
+ KBUILD_MODNAME, reg, len);
+ return -EINVAL;
+ }
+
ret = i2c_transfer(priv->i2c, msg, 2);
if (ret == 2) {
memcpy(val, buf, len);
diff --git a/drivers/media/tuners/tda18212.c b/drivers/media/tuners/tda18212.c
index e4a84ee231cf..abe256e1f843 100644
--- a/drivers/media/tuners/tda18212.c
+++ b/drivers/media/tuners/tda18212.c
@@ -20,6 +20,9 @@
#include "tda18212.h"
+/* Max transfer size done by I2C transfer functions */
+#define MAX_XFER_SIZE 64
+
struct tda18212_priv {
struct tda18212_config *cfg;
struct i2c_adapter *i2c;
@@ -32,16 +35,23 @@ static int tda18212_wr_regs(struct tda18212_priv *priv, u8 reg, u8 *val,
int len)
{
int ret;
- u8 buf[len+1];
+ u8 buf[MAX_XFER_SIZE];
struct i2c_msg msg[1] = {
{
.addr = priv->cfg->i2c_address,
.flags = 0,
- .len = sizeof(buf),
+ .len = 1 + len,
.buf = buf,
}
};
+ if (1 + len > sizeof(buf)) {
+ dev_warn(&priv->i2c->dev,
+ "%s: i2c wr reg=%04x: len=%d is too big!\n",
+ KBUILD_MODNAME, reg, len);
+ return -EINVAL;
+ }
+
buf[0] = reg;
memcpy(&buf[1], val, len);
@@ -61,7 +71,7 @@ static int tda18212_rd_regs(struct tda18212_priv *priv, u8 reg, u8 *val,
int len)
{
int ret;
- u8 buf[len];
+ u8 buf[MAX_XFER_SIZE];
struct i2c_msg msg[2] = {
{
.addr = priv->cfg->i2c_address,
@@ -71,11 +81,18 @@ static int tda18212_rd_regs(struct tda18212_priv *priv, u8 reg, u8 *val,
}, {
.addr = priv->cfg->i2c_address,
.flags = I2C_M_RD,
- .len = sizeof(buf),
+ .len = len,
.buf = buf,
}
};
+ if (len > sizeof(buf)) {
+ dev_warn(&priv->i2c->dev,
+ "%s: i2c rd reg=%04x: len=%d is too big!\n",
+ KBUILD_MODNAME, reg, len);
+ return -EINVAL;
+ }
+
ret = i2c_transfer(priv->i2c, msg, 2);
if (ret == 2) {
memcpy(val, buf, len);
diff --git a/drivers/media/tuners/tda18218.c b/drivers/media/tuners/tda18218.c
index 2d31aeb6b088..9300e9361e3b 100644
--- a/drivers/media/tuners/tda18218.c
+++ b/drivers/media/tuners/tda18218.c
@@ -20,11 +20,14 @@
#include "tda18218_priv.h"
+/* Max transfer size done by I2C transfer functions */
+#define MAX_XFER_SIZE 64
+
/* write multiple registers */
static int tda18218_wr_regs(struct tda18218_priv *priv, u8 reg, u8 *val, u8 len)
{
int ret = 0, len2, remaining;
- u8 buf[1 + len];
+ u8 buf[MAX_XFER_SIZE];
struct i2c_msg msg[1] = {
{
.addr = priv->cfg->i2c_address,
@@ -33,6 +36,13 @@ static int tda18218_wr_regs(struct tda18218_priv *priv, u8 reg, u8 *val, u8 len)
}
};
+ if (1 + len > sizeof(buf)) {
+ dev_warn(&priv->i2c->dev,
+ "%s: i2c wr reg=%04x: len=%d is too big!\n",
+ KBUILD_MODNAME, reg, len);
+ return -EINVAL;
+ }
+
for (remaining = len; remaining > 0;
remaining -= (priv->cfg->i2c_wr_max - 1)) {
len2 = remaining;
@@ -63,7 +73,7 @@ static int tda18218_wr_regs(struct tda18218_priv *priv, u8 reg, u8 *val, u8 len)
static int tda18218_rd_regs(struct tda18218_priv *priv, u8 reg, u8 *val, u8 len)
{
int ret;
- u8 buf[reg+len]; /* we must start read always from reg 0x00 */
+ u8 buf[MAX_XFER_SIZE]; /* we must start read always from reg 0x00 */
struct i2c_msg msg[2] = {
{
.addr = priv->cfg->i2c_address,
@@ -73,11 +83,18 @@ static int tda18218_rd_regs(struct tda18218_priv *priv, u8 reg, u8 *val, u8 len)
}, {
.addr = priv->cfg->i2c_address,
.flags = I2C_M_RD,
- .len = sizeof(buf),
+ .len = reg + len,
.buf = buf,
}
};
+ if (reg + len > sizeof(buf)) {
+ dev_warn(&priv->i2c->dev,
+ "%s: i2c wr reg=%04x: len=%d is too big!\n",
+ KBUILD_MODNAME, reg, len);
+ return -EINVAL;
+ }
+
ret = i2c_transfer(priv->i2c, msg, 2);
if (ret == 2) {
memcpy(val, &buf[reg], len);