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device property: fix for a case of use-after-free

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In device_remove_property_set(), the secondary fwnode needs
to be cleared before the pset is freed. This fixes a
use-after-free when a property set is providing the primary
fwnode.

As a result of the fix, the primary fwnode may end up
containing ERR_PTR(-ENODEV), so also adding checks for it to
the property handling code.

Reported-by: John Youn <John.Youn@synopsys.com>
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Heikki Krogerus 2016-03-10 13:03:18 +02:00 committed by Rafael J. Wysocki
parent 7781203416
commit 0d67e0fa16
1 changed files with 17 additions and 8 deletions
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25
drivers/base/property.c
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@ -218,7 +218,8 @@ bool fwnode_property_present(struct fwnode_handle *fwnode, const char *propname)
bool ret; bool ret;
ret = __fwnode_property_present(fwnode, propname); ret = __fwnode_property_present(fwnode, propname);
if (ret == false && fwnode && !IS_ERR_OR_NULL(fwnode->secondary)) if (ret == false && !IS_ERR_OR_NULL(fwnode) &&
!IS_ERR_OR_NULL(fwnode->secondary))
ret = __fwnode_property_present(fwnode->secondary, propname); ret = __fwnode_property_present(fwnode->secondary, propname);
return ret; return ret;
} }
@ -423,7 +424,8 @@ EXPORT_SYMBOL_GPL(device_property_match_string);
int _ret_; \ int _ret_; \
_ret_ = FWNODE_PROP_READ(_fwnode_, _propname_, _type_, _proptype_, \ _ret_ = FWNODE_PROP_READ(_fwnode_, _propname_, _type_, _proptype_, \
_val_, _nval_); \ _val_, _nval_); \
if (_ret_ == -EINVAL && _fwnode_ && !IS_ERR_OR_NULL(_fwnode_->secondary)) \ if (_ret_ == -EINVAL && !IS_ERR_OR_NULL(_fwnode_) && \
!IS_ERR_OR_NULL(_fwnode_->secondary)) \
_ret_ = FWNODE_PROP_READ(_fwnode_->secondary, _propname_, _type_, \ _ret_ = FWNODE_PROP_READ(_fwnode_->secondary, _propname_, _type_, \
_proptype_, _val_, _nval_); \ _proptype_, _val_, _nval_); \
_ret_; \ _ret_; \
@ -593,7 +595,8 @@ int fwnode_property_read_string_array(struct fwnode_handle *fwnode,
int ret; int ret;
ret = __fwnode_property_read_string_array(fwnode, propname, val, nval); ret = __fwnode_property_read_string_array(fwnode, propname, val, nval);
if (ret == -EINVAL && fwnode && !IS_ERR_OR_NULL(fwnode->secondary)) if (ret == -EINVAL && !IS_ERR_OR_NULL(fwnode) &&
!IS_ERR_OR_NULL(fwnode->secondary))
ret = __fwnode_property_read_string_array(fwnode->secondary, ret = __fwnode_property_read_string_array(fwnode->secondary,
propname, val, nval); propname, val, nval);
return ret; return ret;
@ -621,7 +624,8 @@ int fwnode_property_read_string(struct fwnode_handle *fwnode,
int ret; int ret;
ret = __fwnode_property_read_string(fwnode, propname, val); ret = __fwnode_property_read_string(fwnode, propname, val);
if (ret == -EINVAL && fwnode && !IS_ERR_OR_NULL(fwnode->secondary)) if (ret == -EINVAL && !IS_ERR_OR_NULL(fwnode) &&
!IS_ERR_OR_NULL(fwnode->secondary))
ret = __fwnode_property_read_string(fwnode->secondary, ret = __fwnode_property_read_string(fwnode->secondary,
propname, val); propname, val);
return ret; return ret;
@ -820,11 +824,16 @@ void device_remove_property_set(struct device *dev)
* the pset. If there is no real firmware node (ACPI/DT) primary * the pset. If there is no real firmware node (ACPI/DT) primary
* will hold the pset. * will hold the pset.
*/ */
if (!is_pset_node(fwnode)) if (is_pset_node(fwnode)) {
fwnode = fwnode->secondary; set_primary_fwnode(dev, NULL);
if (!IS_ERR(fwnode) && is_pset_node(fwnode))
pset_free_set(to_pset_node(fwnode)); pset_free_set(to_pset_node(fwnode));
set_secondary_fwnode(dev, NULL); } else {
fwnode = fwnode->secondary;
if (!IS_ERR(fwnode) && is_pset_node(fwnode)) {
set_secondary_fwnode(dev, NULL);
pset_free_set(to_pset_node(fwnode));
}
}
} }
EXPORT_SYMBOL_GPL(device_remove_property_set); EXPORT_SYMBOL_GPL(device_remove_property_set);