[PATCH v2 0/3] device property: post merge fixes

[PATCH v2 0/3] device property: post merge fixes

[Andy Shevchenko]

Three fixes to device property API.

Patch 1 is a simple style fix to be folded into previous Andrew's patch to
allow old gcc to build.

There is a crash in linux-next
 BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
 IP: [<ffffffff8145e8a6>] fwnode_property_present+0x16/0x30

Check for fwnode pointer before dereference (patch 2).

Patch 3 prevents to allocate buffers with 0 length (the result maybe surprising
to someone).


Andy Shevchenko (2):
  device property: add spaces to PROPERTY_ENTRY_STRING macro
  device property: avoid allocations of 0 length

Heikki Krogerus (1):
  device property: the secondary fwnode needs to depend on the primary

 drivers/base/property.c  | 14 ++++++++++----
 include/linux/property.h |  2 +-
 2 files changed, 11 insertions(+), 5 deletions(-)

-- 
2.6.4

[PATCH v2 1/3] device property: add spaces to PROPERTY_ENTRY_STRING macro

[Andy Shevchenko]

Just a style fix, no functional changes.

To be folded to Andrew's patch.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 include/linux/property.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/property.h b/include/linux/property.h
index b8c4e42..b51fcd3 100644
--- a/include/linux/property.h
+++ b/include/linux/property.h
@@ -230,7 +230,7 @@ struct property_entry {
 	.name = _name_,					\
 	.length = sizeof(_val_),			\
 	.is_string = true,				\
-	{ .value = {.str = _val_} },			\
+	{ .value = { .str = _val_ } },			\
 }
 
 #define PROPERTY_ENTRY_BOOL(_name_)		\
-- 
2.6.4

Re: [PATCH v2 1/3] device property: add spaces to PROPERTY_ENTRY_STRING macro

[Rafael J. Wysocki]

On Wednesday, December 23, 2015 03:34:42 PM Andy Shevchenko wrote:
> Just a style fix, no functional changes.
> 
> To be folded to Andrew's patch.

What patch?

> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
>  include/linux/property.h | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/include/linux/property.h b/include/linux/property.h
> index b8c4e42..b51fcd3 100644
> --- a/include/linux/property.h
> +++ b/include/linux/property.h
> @@ -230,7 +230,7 @@ struct property_entry {
>  	.name = _name_,					\
>  	.length = sizeof(_val_),			\
>  	.is_string = true,				\
> -	{ .value = {.str = _val_} },			\
> +	{ .value = { .str = _val_ } },			\
>  }
>  
>  #define PROPERTY_ENTRY_BOOL(_name_)		\
> 

Thanks,
Rafael

Re: [PATCH v2 1/3] device property: add spaces to PROPERTY_ENTRY_STRING macro

[Andy Shevchenko]

On Mon, 2015-12-28 at 02:12 +0100, Rafael J. Wysocki wrote:
> On Wednesday, December 23, 2015 03:34:42 PM Andy Shevchenko wrote:
> > Just a style fix, no functional changes.
> > 
> > To be folded to Andrew's patch.
> 
> What patch?

In linux-next from Andrew:

e39ece7 include-linux-propertyh-fix-build-issues-with-gcc-444-fix
40bb8a1 include/linux/property.h: fix build issues with gcc-4.4.4

> 
> > Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> > ---
> >  include/linux/property.h | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/include/linux/property.h b/include/linux/property.h
> > index b8c4e42..b51fcd3 100644
> > --- a/include/linux/property.h
> > +++ b/include/linux/property.h
> > @@ -230,7 +230,7 @@ struct property_entry {
> >  	.name = _name_,					\
> >  	.length = sizeof(_val_),			\
> >  	.is_string = true,				\
> > -	{ .value = {.str = _val_} },			\
> > +	{ .value = { .str = _val_ } },			\
> >  }
> >  
> >  #define PROPERTY_ENTRY_BOOL(_name_)		\
> > 
> 
> Thanks,
> Rafael
> 

-- 
Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Intel Finland Oy

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Re: [PATCH v2 1/3] device property: add spaces to PROPERTY_ENTRY_STRING macro

[Rafael J. Wysocki]

On Monday, December 28, 2015 01:24:13 PM Andy Shevchenko wrote:
> On Mon, 2015-12-28 at 02:12 +0100, Rafael J. Wysocki wrote:
> > On Wednesday, December 23, 2015 03:34:42 PM Andy Shevchenko wrote:
> > > Just a style fix, no functional changes.
> > > 
> > > To be folded to Andrew's patch.
> > 
> > What patch?
> 
> In linux-next from Andrew:
> 
> e39ece7 include-linux-propertyh-fix-build-issues-with-gcc-444-fix
> 40bb8a1 include/linux/property.h: fix build issues with gcc-4.4.4

Any pointers to the original patch submission(s)?

Thanks,
Rafael

Re: [PATCH v2 1/3] device property: add spaces to PROPERTY_ENTRY_STRING macro

[Andrew Morton]

On Wed, 30 Dec 2015 02:49:26 +0100 "Rafael J. Wysocki" <rjw@rjwysocki.net> wrote:

> On Monday, December 28, 2015 01:24:13 PM Andy Shevchenko wrote:
> > On Mon, 2015-12-28 at 02:12 +0100, Rafael J. Wysocki wrote:
> > > On Wednesday, December 23, 2015 03:34:42 PM Andy Shevchenko wrote:
> > > > Just a style fix, no functional changes.
> > > > 
> > > > To be folded to Andrew's patch.
> > > 
> > > What patch?
> > 
> > In linux-next from Andrew:
> > 
> > e39ece7 include-linux-propertyh-fix-build-issues-with-gcc-444-fix
> > 40bb8a1 include/linux/property.h: fix build issues with gcc-4.4.4
> 
> Any pointers to the original patch submission(s)?

I think it was discussed in some followup to something else, I forget.

This:

From: Andrew Morton <akpm@linux-foundation.org>
Subject: include/linux/property.h: fix build issues with gcc-4.4.4

gcc-4.4.4 has problems with initialization of anonymous unions:

drivers/mfd/intel-lpss-acpi.c:30: error: unknown field 'value' specified in initializer

work around this by crafting the initializers in a manner which the
compiler can handle.

Cc: Kevin Fenzi <kevin@scrye.com>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/linux/property.h |   16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff -puN include/linux/property.h~include-linux-propertyh-fix-build-issues-with-gcc-444 include/linux/property.h
--- a/include/linux/property.h~include-linux-propertyh-fix-build-issues-with-gcc-444
+++ a/include/linux/property.h
@@ -175,12 +175,19 @@ struct property_entry {
 	};
 };
 
+/*
+ * Note: the below four initializers for the anonymous union are carefully
+ * crafted to avoid gcc-4.4.4's problems with initialization of anon unions
+ * and structs.
+ */
+
 #define PROPERTY_ENTRY_INTEGER_ARRAY(_name_, _type_, _val_)	\
 {								\
 	.name = _name_,						\
 	.length = ARRAY_SIZE(_val_) * sizeof(_type_),		\
 	.is_array = true,					\
-	.pointer._type_##_data = _val_,				\
+	.is_string = false,					\
+	{ .pointer = _type_##_data = _val_ } },			\
 }
 
 #define PROPERTY_ENTRY_U8_ARRAY(_name_, _val_)			\
@@ -198,14 +205,15 @@ struct property_entry {
 	.length = ARRAY_SIZE(_val_) * sizeof(const char *),	\
 	.is_array = true,					\
 	.is_string = true,					\
-	.pointer.str = _val_,					\
+	{ .pointer = { .str = _val_ } },			\
 }
 
 #define PROPERTY_ENTRY_INTEGER(_name_, _type_, _val_)	\
 {							\
 	.name = _name_,					\
 	.length = sizeof(_type_),			\
-	.value._type_##_data = _val_,			\
+	.is_string = false,				\
+	{ .value = { ._type_##_data = _val_ } },	\
 }
 
 #define PROPERTY_ENTRY_U8(_name_, _val_)		\
@@ -222,7 +230,7 @@ struct property_entry {
 	.name = _name_,					\
 	.length = sizeof(_val_),			\
 	.is_string = true,				\
-	.value.str = _val_,				\
+	{ .value = {.str = _val_} },			\
 }
 
 #define PROPERTY_ENTRY_BOOL(_name_)		\
_

Re: [PATCH v2 1/3] device property: add spaces to PROPERTY_ENTRY_STRING macro

[Rafael J. Wysocki]

On Tuesday, December 29, 2015 05:24:53 PM Andrew Morton wrote:
> On Wed, 30 Dec 2015 02:49:26 +0100 "Rafael J. Wysocki" <rjw@rjwysocki.net> wrote:
> 
> > On Monday, December 28, 2015 01:24:13 PM Andy Shevchenko wrote:
> > > On Mon, 2015-12-28 at 02:12 +0100, Rafael J. Wysocki wrote:
> > > > On Wednesday, December 23, 2015 03:34:42 PM Andy Shevchenko wrote:
> > > > > Just a style fix, no functional changes.
> > > > > 
> > > > > To be folded to Andrew's patch.
> > > > 
> > > > What patch?
> > > 
> > > In linux-next from Andrew:
> > > 
> > > e39ece7 include-linux-propertyh-fix-build-issues-with-gcc-444-fix
> > > 40bb8a1 include/linux/property.h: fix build issues with gcc-4.4.4
> > 
> > Any pointers to the original patch submission(s)?
> 
> I think it was discussed in some followup to something else, I forget.
> 
> This:
> 
> From: Andrew Morton <akpm@linux-foundation.org>
> Subject: include/linux/property.h: fix build issues with gcc-4.4.4

OK, thanks!

I'll apply it to my tree if you don't mind with the Andy's [1/3] on top
so we have all of that in one place.

Thanks,
Rafael

Re: [PATCH v2 1/3] device property: add spaces to PROPERTY_ENTRY_STRING macro

[Andy Shevchenko]

On Wed, Dec 30, 2015 at 4:06 AM, Rafael J. Wysocki <rjw@rjwysocki.net> wrote:
> On Tuesday, December 29, 2015 05:24:53 PM Andrew Morton wrote:
>> On Wed, 30 Dec 2015 02:49:26 +0100 "Rafael J. Wysocki" <rjw@rjwysocki.net> wrote:
>>
>> > On Monday, December 28, 2015 01:24:13 PM Andy Shevchenko wrote:
>> > > On Mon, 2015-12-28 at 02:12 +0100, Rafael J. Wysocki wrote:
>> > > > On Wednesday, December 23, 2015 03:34:42 PM Andy Shevchenko wrote:
>> > > > > Just a style fix, no functional changes.
>> > > > >
>> > > > > To be folded to Andrew's patch.
>> > > >
>> > > > What patch?
>> > >
>> > > In linux-next from Andrew:
>> > >
>> > > e39ece7 include-linux-propertyh-fix-build-issues-with-gcc-444-fix
>> > > 40bb8a1 include/linux/property.h: fix build issues with gcc-4.4.4
>> >
>> > Any pointers to the original patch submission(s)?
>>
>> I think it was discussed in some followup to something else, I forget.
>>
>> This:
>>
>> From: Andrew Morton <akpm@linux-foundation.org>
>> Subject: include/linux/property.h: fix build issues with gcc-4.4.4
>
> OK, thanks!
>
> I'll apply it to my tree if you don't mind with the Andy's [1/3] on top
> so we have all of that in one place.

Be aware that there are actually _two_ patches from Andrew and _one_
from me to be all folded together.
I think there is no need to have 3 of them.

>
> Thanks,
> Rafael
>
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> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
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-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v2 1/3] device property: add spaces to PROPERTY_ENTRY_STRING macro

[Andrew Morton]

On Wed, 30 Dec 2015 03:06:23 +0100 "Rafael J. Wysocki" <rjw@rjwysocki.net> wrote:

> I'll apply it to my tree if you don't mind with the Andy's [1/3] on top
> so we have all of that in one place.

That version needed a fix.  Here's the one to apply:


From: Andrew Morton <akpm@linux-foundation.org>
Subject: include/linux/property.h: fix build issues with gcc-4.4.4

gcc-4.4.4 has problems with initialization of anonymous unions:

drivers/mfd/intel-lpss-acpi.c:30: error: unknown field 'value' specified in initializer

work around this by crafting the initializers in a manner which the
compiler can handle.

Cc: Kevin Fenzi <kevin@scrye.com>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/linux/property.h |   16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff -puN include/linux/property.h~include-linux-propertyh-fix-build-issues-with-gcc-444 include/linux/property.h
--- a/include/linux/property.h~include-linux-propertyh-fix-build-issues-with-gcc-444
+++ a/include/linux/property.h
@@ -175,12 +175,19 @@ struct property_entry {
 	};
 };
 
+/*
+ * Note: the below four initializers for the anonymous union are carefully
+ * crafted to avoid gcc-4.4.4's problems with initialization of anon unions
+ * and structs.
+ */
+
 #define PROPERTY_ENTRY_INTEGER_ARRAY(_name_, _type_, _val_)	\
 {								\
 	.name = _name_,						\
 	.length = ARRAY_SIZE(_val_) * sizeof(_type_),		\
 	.is_array = true,					\
-	.pointer._type_##_data = _val_,				\
+	.is_string = false,					\
+	{ .pointer = { _type_##_data = _val_ } },		\
 }
 
 #define PROPERTY_ENTRY_U8_ARRAY(_name_, _val_)			\
@@ -198,14 +205,15 @@ struct property_entry {
 	.length = ARRAY_SIZE(_val_) * sizeof(const char *),	\
 	.is_array = true,					\
 	.is_string = true,					\
-	.pointer.str = _val_,					\
+	{ .pointer = { .str = _val_ } },			\
 }
 
 #define PROPERTY_ENTRY_INTEGER(_name_, _type_, _val_)	\
 {							\
 	.name = _name_,					\
 	.length = sizeof(_type_),			\
-	.value._type_##_data = _val_,			\
+	.is_string = false,				\
+	{ .value = { ._type_##_data = _val_ } },	\
 }
 
 #define PROPERTY_ENTRY_U8(_name_, _val_)		\
@@ -222,7 +230,7 @@ struct property_entry {
 	.name = _name_,					\
 	.length = sizeof(_val_),			\
 	.is_string = true,				\
-	.value.str = _val_,				\
+	{ .value = {.str = _val_} },			\
 }
 
 #define PROPERTY_ENTRY_BOOL(_name_)		\
_

Re: [PATCH v2 1/3] device property: add spaces to PROPERTY_ENTRY_STRING macro

[Rafael J. Wysocki]

On Tuesday, December 29, 2015 05:44:48 PM Andrew Morton wrote:
> On Wed, 30 Dec 2015 03:06:23 +0100 "Rafael J. Wysocki" <rjw@rjwysocki.net> wrote:
> 
> > I'll apply it to my tree if you don't mind with the Andy's [1/3] on top
> > so we have all of that in one place.
> 
> That version needed a fix.  Here's the one to apply:

OK, thanks!

Re: [PATCH v2 1/3] device property: add spaces to PROPERTY_ENTRY_STRING macro

[Andy Shevchenko]

On Wed, Dec 30, 2015 at 3:49 AM, Rafael J. Wysocki <rjw@rjwysocki.net> wrote:
> On Monday, December 28, 2015 01:24:13 PM Andy Shevchenko wrote:
>> On Mon, 2015-12-28 at 02:12 +0100, Rafael J. Wysocki wrote:
>> > On Wednesday, December 23, 2015 03:34:42 PM Andy Shevchenko wrote:
>> > > Just a style fix, no functional changes.
>> > >
>> > > To be folded to Andrew's patch.
>> >
>> > What patch?
>>
>> In linux-next from Andrew:
>>
>> e39ece7 include-linux-propertyh-fix-build-issues-with-gcc-444-fix
>> 40bb8a1 include/linux/property.h: fix build issues with gcc-4.4.4
>
> Any pointers to the original patch submission(s)?

Yes, I found one [1] and added to v3 of this patch [2]

[1] http://comments.gmane.org/gmane.linux.kernel.commits.mm/97592
[2] http://www.spinics.net/lists/kernel/msg2151801.html

>
> Thanks,
> Rafael
>
> --
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> the body of a message to majordomo@vger.kernel.org
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> Please read the FAQ at  http://www.tux.org/lkml/



-- 
With Best Regards,
Andy Shevchenko

[PATCH v2 2/3] device property: the secondary fwnode needs to depend on the primary

[Andy Shevchenko]

From: Heikki Krogerus <heikki.krogerus@linux.intel.com>

This fixes NULL pointer dereference when the primary fwnode handle
does not exist, for example with PCI devices that do not have ACPI
companion.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/base/property.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/base/property.c b/drivers/base/property.c
index 0b22c8a..6c04d18 100644
--- a/drivers/base/property.c
+++ b/drivers/base/property.c
@@ -218,7 +218,7 @@ bool fwnode_property_present(struct fwnode_handle *fwnode, const char *propname)
 	bool ret;
 
 	ret = __fwnode_property_present(fwnode, propname);
-	if (ret == false && fwnode->secondary)
+	if (ret == false && fwnode && fwnode->secondary)
 		ret = __fwnode_property_present(fwnode->secondary, propname);
 	return ret;
 }
@@ -423,7 +423,7 @@ EXPORT_SYMBOL_GPL(device_property_match_string);
 	int _ret_;									\
 	_ret_ = FWNODE_PROP_READ(_fwnode_, _propname_, _type_, _proptype_,		\
 				 _val_, _nval_);					\
-	if (_ret_ == -EINVAL && _fwnode_->secondary)					\
+	if (_ret_ == -EINVAL && fwnode && _fwnode_->secondary)				\
 		_ret_ = FWNODE_PROP_READ(_fwnode_->secondary, _propname_, _type_,	\
 				_proptype_, _val_, _nval_);				\
 	_ret_;										\
@@ -593,7 +593,7 @@ int fwnode_property_read_string_array(struct fwnode_handle *fwnode,
 	int ret;
 
 	ret = __fwnode_property_read_string_array(fwnode, propname, val, nval);
-	if (ret == -EINVAL && fwnode->secondary)
+	if (ret == -EINVAL && fwnode && fwnode->secondary)
 		ret = __fwnode_property_read_string_array(fwnode->secondary,
 							  propname, val, nval);
 	return ret;
@@ -621,7 +621,7 @@ int fwnode_property_read_string(struct fwnode_handle *fwnode,
 	int ret;
 
 	ret = __fwnode_property_read_string(fwnode, propname, val);
-	if (ret == -EINVAL && fwnode->secondary)
+	if (ret == -EINVAL && fwnode && fwnode->secondary)
 		ret = __fwnode_property_read_string(fwnode->secondary,
 						    propname, val);
 	return ret;
-- 
2.6.4

Re: [PATCH v2 2/3] device property: the secondary fwnode needs to depend on the primary

[Heikki Krogerus]

Hi Andy,

Found a bug from my code..

> diff --git a/drivers/base/property.c b/drivers/base/property.c
> index 0b22c8a..6c04d18 100644
> --- a/drivers/base/property.c
> +++ b/drivers/base/property.c
> @@ -218,7 +218,7 @@ bool fwnode_property_present(struct fwnode_handle *fwnode, const char *propname)
>  	bool ret;
>  
>  	ret = __fwnode_property_present(fwnode, propname);
> -	if (ret == false && fwnode->secondary)
> +	if (ret == false && fwnode && fwnode->secondary)
>  		ret = __fwnode_property_present(fwnode->secondary, propname);
>  	return ret;
>  }
> @@ -423,7 +423,7 @@ EXPORT_SYMBOL_GPL(device_property_match_string);
>  	int _ret_;									\
>  	_ret_ = FWNODE_PROP_READ(_fwnode_, _propname_, _type_, _proptype_,		\
>  				 _val_, _nval_);					\
> -	if (_ret_ == -EINVAL && _fwnode_->secondary)					\
> +	if (_ret_ == -EINVAL && fwnode && _fwnode_->secondary)				\

This should be .._fwnode_ && _fwnode_->secondary)

>  		_ret_ = FWNODE_PROP_READ(_fwnode_->secondary, _propname_, _type_,	\
>  				_proptype_, _val_, _nval_);				\
>  	_ret_;										\


Cheers,

-- 
heikki

Re: [PATCH v2 2/3] device property: the secondary fwnode needs to depend on the primary

[Andy Shevchenko]

On Tue, 2015-12-29 at 10:40 +0200, Heikki Krogerus wrote:
> Hi Andy,
> 
> Found a bug from my code..
> 
> > diff --git a/drivers/base/property.c b/drivers/base/property.c
> > index 0b22c8a..6c04d18 100644
> > --- a/drivers/base/property.c
> > +++ b/drivers/base/property.c
> > @@ -218,7 +218,7 @@ bool fwnode_property_present(struct
> > fwnode_handle *fwnode, const char *propname)
> >  	bool ret;
> >  
> >  	ret = __fwnode_property_present(fwnode, propname);
> > -	if (ret == false && fwnode->secondary)
> > +	if (ret == false && fwnode && fwnode->secondary)
> >  		ret = __fwnode_property_present(fwnode->secondary, 
> > propname);
> >  	return ret;
> >  }
> > @@ -423,7 +423,7 @@
> > EXPORT_SYMBOL_GPL(device_property_match_string);
> >  	int _ret_;							
> > 		\
> >  	_ret_ = FWNODE_PROP_READ(_fwnode_, _propname_, _type_,
> > _proptype_,		\
> >  				 _val_, _nval_);			
> > 		\
> > -	if (_ret_ == -EINVAL && _fwnode_->secondary)		
> > 			\
> > +	if (_ret_ == -EINVAL && fwnode && _fwnode_->secondary)	
> > 			\
> 
> This should be .._fwnode_ && _fwnode_->secondary)

Yeah, we compiled it correctly due to fwnode presents in all
occurrences of this macro.

I will fix and resend a new version.

> 
> >  		_ret_ = FWNODE_PROP_READ(_fwnode_->secondary,
> > _propname_, _type_,	\
> >  				_proptype_, _val_, _nval_);	
> > 			\
> >  	_ret_;							
> > 			\
> 
> 
> Cheers,
> 

-- 
Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Intel Finland Oy

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[PATCH v2 3/3] device property: avoid allocations of 0 length

[Andy Shevchenko]

Arrays can not have zero elements by definition of the unified device
properties. If such property comes from outside we should not allow it to pass.
Otherwise memory allocation on 0 length will return non-NULL value, which we
currently don't check.

Prevent memory allocations of 0 length.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/base/property.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/base/property.c b/drivers/base/property.c
index 6c04d18..7e2061b 100644
--- a/drivers/base/property.c
+++ b/drivers/base/property.c
@@ -653,6 +653,9 @@ int fwnode_property_match_string(struct fwnode_handle *fwnode,
 	if (nval < 0)
 		return nval;
 
+	if (nval == 0)
+		return -ENODATA;
+
 	values = kcalloc(nval, sizeof(*values), GFP_KERNEL);
 	if (!values)
 		return -ENOMEM;
@@ -718,6 +721,9 @@ static int pset_copy_entry(struct property_entry *dst,
 		return -ENOMEM;
 
 	if (src->is_array) {
+		if (!src->length)
+			return -ENODATA;
+
 		if (src->is_string) {
 			nval = src->length / sizeof(const char *);
 			dst->pointer.str = kcalloc(nval, sizeof(const char *),
-- 
2.6.4