[3.11.y.z extended stable] Patch "[media] dvb-frontends: Don't use dynamic static allocation" has been added to staging queue
Luis Henriques
luis.henriques at canonical.com
Thu Dec 5 11:24:47 UTC 2013
This is a note to let you know that I have just added a patch titled
[media] dvb-frontends: Don't use dynamic static allocation
to the linux-3.11.y-queue branch of the 3.11.y.z extended stable tree
which can be found at:
http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.11.y-queue
If you, or anyone else, feels it should not be added to this tree, please
reply to this email.
For more information about the 3.11.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable
Thanks.
-Luis
------
>From 698c098c1c8c3eef7a20b17ae57bb35ee579a413 Mon Sep 17 00:00:00 2001
From: Mauro Carvalho Chehab <m.chehab at samsung.com>
Date: Sat, 2 Nov 2013 05:11:47 -0300
Subject: [media] dvb-frontends: Don't use dynamic static allocation
commit 37ebaf6891ee81687bb558e8375c0712d8264ed8 upstream.
Dynamic static allocation is evil, as Kernel stack is too low, and
compilation complains about it on some archs:
drivers/media/dvb-frontends/af9013.c:77:1: warning: 'af9013_wr_regs_i2c' uses dynamic stack allocation [enabled by default]
drivers/media/dvb-frontends/af9033.c:188:1: warning: 'af9033_wr_reg_val_tab' uses dynamic stack allocation [enabled by default]
drivers/media/dvb-frontends/af9033.c:68:1: warning: 'af9033_wr_regs' uses dynamic stack allocation [enabled by default]
drivers/media/dvb-frontends/bcm3510.c:230:1: warning: 'bcm3510_do_hab_cmd' uses dynamic stack allocation [enabled by default]
drivers/media/dvb-frontends/cxd2820r_core.c:84:1: warning: 'cxd2820r_rd_regs_i2c.isra.1' uses dynamic stack allocation [enabled by default]
drivers/media/dvb-frontends/rtl2830.c:56:1: warning: 'rtl2830_wr' uses dynamic stack allocation [enabled by default]
drivers/media/dvb-frontends/rtl2832.c:187:1: warning: 'rtl2832_wr' uses dynamic stack allocation [enabled by default]
drivers/media/dvb-frontends/tda10071.c:52:1: warning: 'tda10071_wr_regs' uses dynamic stack allocation [enabled by default]
drivers/media/dvb-frontends/tda10071.c:84:1: warning: 'tda10071_rd_regs' 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 at samsung.com>
Reviewed-by: Hans Verkuil <hans.verkuil at cisco.com>
Reviewed-by: Antti Palosaari <crope at iki.fi>
Signed-off-by: Mauro Carvalho Chehab <m.chehab at samsung.com>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
drivers/media/dvb-frontends/af9013.c | 14 ++++++++++++--
drivers/media/dvb-frontends/af9033.c | 23 ++++++++++++++++++++---
drivers/media/dvb-frontends/cxd2820r_core.c | 21 +++++++++++++++++++--
drivers/media/dvb-frontends/rtl2830.c | 14 ++++++++++++--
drivers/media/dvb-frontends/rtl2832.c | 14 ++++++++++++--
drivers/media/dvb-frontends/tda10071.c | 25 +++++++++++++++++++++----
6 files changed, 96 insertions(+), 15 deletions(-)
diff --git a/drivers/media/dvb-frontends/af9013.c b/drivers/media/dvb-frontends/af9013.c
index a204f28..fb504f1 100644
--- a/drivers/media/dvb-frontends/af9013.c
+++ b/drivers/media/dvb-frontends/af9013.c
@@ -24,6 +24,9 @@
#include "af9013_priv.h"
+/* Max transfer size done by I2C transfer functions */
+#define MAX_XFER_SIZE 64
+
struct af9013_state {
struct i2c_adapter *i2c;
struct dvb_frontend fe;
@@ -50,16 +53,23 @@ static int af9013_wr_regs_i2c(struct af9013_state *priv, u8 mbox, u16 reg,
const u8 *val, int len)
{
int ret;
- u8 buf[3+len];
+ u8 buf[MAX_XFER_SIZE];
struct i2c_msg msg[1] = {
{
.addr = priv->config.i2c_addr,
.flags = 0,
- .len = sizeof(buf),
+ .len = 3 + len,
.buf = buf,
}
};
+ if (3 + 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 >> 8) & 0xff;
buf[1] = (reg >> 0) & 0xff;
buf[2] = mbox;
diff --git a/drivers/media/dvb-frontends/af9033.c b/drivers/media/dvb-frontends/af9033.c
index a777b4b..30ee590 100644
--- a/drivers/media/dvb-frontends/af9033.c
+++ b/drivers/media/dvb-frontends/af9033.c
@@ -21,6 +21,9 @@
#include "af9033_priv.h"
+/* Max transfer size done by I2C transfer functions */
+#define MAX_XFER_SIZE 64
+
struct af9033_state {
struct i2c_adapter *i2c;
struct dvb_frontend fe;
@@ -40,16 +43,23 @@ static int af9033_wr_regs(struct af9033_state *state, u32 reg, const u8 *val,
int len)
{
int ret;
- u8 buf[3 + len];
+ u8 buf[MAX_XFER_SIZE];
struct i2c_msg msg[1] = {
{
.addr = state->cfg.i2c_addr,
.flags = 0,
- .len = sizeof(buf),
+ .len = 3 + len,
.buf = buf,
}
};
+ if (3 + len > sizeof(buf)) {
+ dev_warn(&state->i2c->dev,
+ "%s: i2c wr reg=%04x: len=%d is too big!\n",
+ KBUILD_MODNAME, reg, len);
+ return -EINVAL;
+ }
+
buf[0] = (reg >> 16) & 0xff;
buf[1] = (reg >> 8) & 0xff;
buf[2] = (reg >> 0) & 0xff;
@@ -161,7 +171,14 @@ static int af9033_wr_reg_val_tab(struct af9033_state *state,
const struct reg_val *tab, int tab_len)
{
int ret, i, j;
- u8 buf[tab_len];
+ u8 buf[MAX_XFER_SIZE];
+
+ if (tab_len > sizeof(buf)) {
+ dev_warn(&state->i2c->dev,
+ "%s: i2c wr len=%d is too big!\n",
+ KBUILD_MODNAME, tab_len);
+ return -EINVAL;
+ }
dev_dbg(&state->i2c->dev, "%s: tab_len=%d\n", __func__, tab_len);
diff --git a/drivers/media/dvb-frontends/cxd2820r_core.c b/drivers/media/dvb-frontends/cxd2820r_core.c
index 7ca5c69..51447a0 100644
--- a/drivers/media/dvb-frontends/cxd2820r_core.c
+++ b/drivers/media/dvb-frontends/cxd2820r_core.c
@@ -21,12 +21,15 @@
#include "cxd2820r_priv.h"
+/* Max transfer size done by I2C transfer functions */
+#define MAX_XFER_SIZE 64
+
/* write multiple registers */
static int cxd2820r_wr_regs_i2c(struct cxd2820r_priv *priv, u8 i2c, u8 reg,
u8 *val, int len)
{
int ret;
- u8 buf[len+1];
+ u8 buf[MAX_XFER_SIZE];
struct i2c_msg msg[1] = {
{
.addr = i2c,
@@ -36,6 +39,13 @@ static int cxd2820r_wr_regs_i2c(struct cxd2820r_priv *priv, u8 i2c, u8 reg,
}
};
+ 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);
@@ -55,7 +65,7 @@ static int cxd2820r_rd_regs_i2c(struct cxd2820r_priv *priv, u8 i2c, u8 reg,
u8 *val, int len)
{
int ret;
- u8 buf[len];
+ u8 buf[MAX_XFER_SIZE];
struct i2c_msg msg[2] = {
{
.addr = i2c,
@@ -70,6 +80,13 @@ static int cxd2820r_rd_regs_i2c(struct cxd2820r_priv *priv, u8 i2c, u8 reg,
}
};
+ if (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, len);
diff --git a/drivers/media/dvb-frontends/rtl2830.c b/drivers/media/dvb-frontends/rtl2830.c
index 362d26d..7efb796 100644
--- a/drivers/media/dvb-frontends/rtl2830.c
+++ b/drivers/media/dvb-frontends/rtl2830.c
@@ -27,20 +27,30 @@
#include "rtl2830_priv.h"
+/* Max transfer size done by I2C transfer functions */
+#define MAX_XFER_SIZE 64
+
/* write multiple hardware registers */
static int rtl2830_wr(struct rtl2830_priv *priv, u8 reg, const 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 = 1+len,
+ .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);
diff --git a/drivers/media/dvb-frontends/rtl2832.c b/drivers/media/dvb-frontends/rtl2832.c
index facb848..b8dd0a1 100644
--- a/drivers/media/dvb-frontends/rtl2832.c
+++ b/drivers/media/dvb-frontends/rtl2832.c
@@ -22,6 +22,9 @@
#include "dvb_math.h"
#include <linux/bitops.h>
+/* Max transfer size done by I2C transfer functions */
+#define MAX_XFER_SIZE 64
+
int rtl2832_debug;
module_param_named(debug, rtl2832_debug, int, 0644);
MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");
@@ -162,16 +165,23 @@ static const struct rtl2832_reg_entry registers[] = {
static int rtl2832_wr(struct rtl2832_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 = 1+len,
+ .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);
diff --git a/drivers/media/dvb-frontends/tda10071.c b/drivers/media/dvb-frontends/tda10071.c
index 2521f7e..36eb27d 100644
--- a/drivers/media/dvb-frontends/tda10071.c
+++ b/drivers/media/dvb-frontends/tda10071.c
@@ -20,6 +20,9 @@
#include "tda10071_priv.h"
+/* Max transfer size done by I2C transfer functions */
+#define MAX_XFER_SIZE 64
+
static struct dvb_frontend_ops tda10071_ops;
/* write multiple registers */
@@ -27,16 +30,23 @@ static int tda10071_wr_regs(struct tda10071_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.demod_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);
@@ -56,7 +66,7 @@ static int tda10071_rd_regs(struct tda10071_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.demod_i2c_addr,
@@ -66,11 +76,18 @@ static int tda10071_rd_regs(struct tda10071_priv *priv, u8 reg, u8 *val,
}, {
.addr = priv->cfg.demod_i2c_addr,
.flags = I2C_M_RD,
- .len = sizeof(buf),
+ .len = len,
.buf = buf,
}
};
+ if (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, len);
--
1.8.3.2
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