[PATCH v3 0/3] device property: post merge fixes

[PATCH v3 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 (see commit message for the details).

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).

Changelog v3:
- fix typo in Heikki's patch (patch 2)
- update commit message for patch 1 to explain what is the fixup for

Changelog v2:
- added patches 2 and 3

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 v3 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 [1].

[1] http://comments.gmane.org/gmane.linux.kernel.commits.mm/97592

Or in linux next:

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_)		\
-- 
2.6.4

[PATCH v3 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..b3429cc 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

[PATCH v3 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 b3429cc..c359351 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