* [patch] i2c-scmi: remove some bogus NULL checks
@ 2013-10-19 8:46 Dan Carpenter
[not found] ` <20131019084622.GA9312-dZEljifmRObu9KfB+GxooP8+0UxHXcjY@public.gmane.org>
2013-10-31 11:57 ` Wolfram Sang
0 siblings, 2 replies; 4+ messages in thread
From: Dan Carpenter @ 2013-10-19 8:46 UTC (permalink / raw)
To: Wolfram Sang
Cc: Jiang Liu, Toshi Kani, Rafael J. Wysocki, Yinghai Lu, linux-i2c,
kernel-janitors
"obj" can't be NULL here.
We already know that "pkg->package.elements" gives us a valid pointer
so the next pointer after that is also non-NULL.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
diff --git a/drivers/i2c/busses/i2c-scmi.c b/drivers/i2c/busses/i2c-scmi.c
index c447e8d..5992355 100644
--- a/drivers/i2c/busses/i2c-scmi.c
+++ b/drivers/i2c/busses/i2c-scmi.c
@@ -223,7 +223,7 @@ acpi_smbus_cmi_access(struct i2c_adapter *adap, u16 addr, unsigned short flags,
goto out;
obj = pkg->package.elements + 1;
- if (obj == NULL || obj->type != ACPI_TYPE_INTEGER) {
+ if (obj->type != ACPI_TYPE_INTEGER) {
ACPI_ERROR((AE_INFO, "Invalid argument type"));
result = -EIO;
goto out;
@@ -235,7 +235,7 @@ acpi_smbus_cmi_access(struct i2c_adapter *adap, u16 addr, unsigned short flags,
case I2C_SMBUS_BYTE:
case I2C_SMBUS_BYTE_DATA:
case I2C_SMBUS_WORD_DATA:
- if (obj == NULL || obj->type != ACPI_TYPE_INTEGER) {
+ if (obj->type != ACPI_TYPE_INTEGER) {
ACPI_ERROR((AE_INFO, "Invalid argument type"));
result = -EIO;
goto out;
@@ -246,7 +246,7 @@ acpi_smbus_cmi_access(struct i2c_adapter *adap, u16 addr, unsigned short flags,
data->byte = obj->integer.value;
break;
case I2C_SMBUS_BLOCK_DATA:
- if (obj == NULL || obj->type != ACPI_TYPE_BUFFER) {
+ if (obj->type != ACPI_TYPE_BUFFER) {
ACPI_ERROR((AE_INFO, "Invalid argument type"));
result = -EIO;
goto out;
^ permalink raw reply related [flat|nested] 4+ messages in thread[parent not found: <20131019084622.GA9312-dZEljifmRObu9KfB+GxooP8+0UxHXcjY@public.gmane.org>]
* Re: [patch] i2c-scmi: remove some bogus NULL checks
[not found] ` <20131019084622.GA9312-dZEljifmRObu9KfB+GxooP8+0UxHXcjY@public.gmane.org>
@ 2013-10-30 16:02 ` Wolfram Sang
2013-10-30 16:39 ` Dan Carpenter
0 siblings, 1 reply; 4+ messages in thread
From: Wolfram Sang @ 2013-10-30 16:02 UTC (permalink / raw)
To: Dan Carpenter
Cc: Jiang Liu, Toshi Kani, Rafael J. Wysocki, Yinghai Lu,
linux-i2c-u79uwXL29TY76Z2rM5mHXA,
kernel-janitors-u79uwXL29TY76Z2rM5mHXA
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On Sat, Oct 19, 2013 at 11:46:22AM +0300, Dan Carpenter wrote:
> "obj" can't be NULL here.
>
> We already know that "pkg->package.elements" gives us a valid pointer
> so the next pointer after that is also non-NULL.
Why is that? Can't see it...
>
> Signed-off-by: Dan Carpenter <dan.carpenter-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org>
>
> diff --git a/drivers/i2c/busses/i2c-scmi.c b/drivers/i2c/busses/i2c-scmi.c
> index c447e8d..5992355 100644
> --- a/drivers/i2c/busses/i2c-scmi.c
> +++ b/drivers/i2c/busses/i2c-scmi.c
> @@ -223,7 +223,7 @@ acpi_smbus_cmi_access(struct i2c_adapter *adap, u16 addr, unsigned short flags,
> goto out;
>
> obj = pkg->package.elements + 1;
> - if (obj == NULL || obj->type != ACPI_TYPE_INTEGER) {
> + if (obj->type != ACPI_TYPE_INTEGER) {
> ACPI_ERROR((AE_INFO, "Invalid argument type"));
> result = -EIO;
> goto out;
> @@ -235,7 +235,7 @@ acpi_smbus_cmi_access(struct i2c_adapter *adap, u16 addr, unsigned short flags,
> case I2C_SMBUS_BYTE:
> case I2C_SMBUS_BYTE_DATA:
> case I2C_SMBUS_WORD_DATA:
> - if (obj == NULL || obj->type != ACPI_TYPE_INTEGER) {
> + if (obj->type != ACPI_TYPE_INTEGER) {
> ACPI_ERROR((AE_INFO, "Invalid argument type"));
> result = -EIO;
> goto out;
> @@ -246,7 +246,7 @@ acpi_smbus_cmi_access(struct i2c_adapter *adap, u16 addr, unsigned short flags,
> data->byte = obj->integer.value;
> break;
> case I2C_SMBUS_BLOCK_DATA:
> - if (obj == NULL || obj->type != ACPI_TYPE_BUFFER) {
> + if (obj->type != ACPI_TYPE_BUFFER) {
> ACPI_ERROR((AE_INFO, "Invalid argument type"));
> result = -EIO;
> goto out;
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^ permalink raw reply [flat|nested] 4+ messages in thread* Re: [patch] i2c-scmi: remove some bogus NULL checks
2013-10-30 16:02 ` Wolfram Sang
@ 2013-10-30 16:39 ` Dan Carpenter
0 siblings, 0 replies; 4+ messages in thread
From: Dan Carpenter @ 2013-10-30 16:39 UTC (permalink / raw)
To: Wolfram Sang
Cc: Jiang Liu, Toshi Kani, Rafael J. Wysocki, Yinghai Lu, linux-i2c,
kernel-janitors
On Wed, Oct 30, 2013 at 05:02:58PM +0100, Wolfram Sang wrote:
> > --- a/drivers/i2c/busses/i2c-scmi.c
> > +++ b/drivers/i2c/busses/i2c-scmi.c
> > @@ -223,7 +223,7 @@ acpi_smbus_cmi_access(struct i2c_adapter *adap, u16 addr, unsigned short flags,
> > goto out;
> >
> > obj = pkg->package.elements + 1;
> > - if (obj == NULL || obj->type != ACPI_TYPE_INTEGER) {
> > + if (obj->type != ACPI_TYPE_INTEGER) {
> > ACPI_ERROR((AE_INFO, "Invalid argument type"));
> > result = -EIO;
> > goto out;
For obj to be 0 then pkg->package.elements must be -1. If we're getting
a pointer of -1 then we're already screwed. Also we already used
pkg->elements without the "+ 1" so we know that's not -1.
The reason for this patch was that some compilers assume pointer math
can't overflow and my checker was complaining. We use
-fno-strict-overflow in the kernel, but it still seemed worth cleaning.
regards,
dan carpenter
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [patch] i2c-scmi: remove some bogus NULL checks
2013-10-19 8:46 [patch] i2c-scmi: remove some bogus NULL checks Dan Carpenter
[not found] ` <20131019084622.GA9312-dZEljifmRObu9KfB+GxooP8+0UxHXcjY@public.gmane.org>
@ 2013-10-31 11:57 ` Wolfram Sang
1 sibling, 0 replies; 4+ messages in thread
From: Wolfram Sang @ 2013-10-31 11:57 UTC (permalink / raw)
To: Dan Carpenter
Cc: Jiang Liu, Toshi Kani, Rafael J. Wysocki, Yinghai Lu, linux-i2c,
kernel-janitors
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On Sat, Oct 19, 2013 at 11:46:22AM +0300, Dan Carpenter wrote:
> "obj" can't be NULL here.
>
> We already know that "pkg->package.elements" gives us a valid pointer
> so the next pointer after that is also non-NULL.
>
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Applied to for-next, thanks!
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^ permalink raw reply [flat|nested] 4+ messages in thread
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2013-10-19 8:46 [patch] i2c-scmi: remove some bogus NULL checks Dan Carpenter
[not found] ` <20131019084622.GA9312-dZEljifmRObu9KfB+GxooP8+0UxHXcjY@public.gmane.org>
2013-10-30 16:02 ` Wolfram Sang
2013-10-30 16:39 ` Dan Carpenter
2013-10-31 11:57 ` Wolfram Sang
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